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With social-distancing measures being implemented in many countries I would expect other viruses, like the ones that cause seasonal flus, to have also a hard time propagating in these circumstances. Are there any estimates or research (epidemiological models) I can check, about the possibility we are winning by accident a war against many other less alarming viruses?
Yes, this helps as well with other infectious diseases. A good example is the flu, which season was measurably shorter this year than in other years on record. See the figure from the reference 1 for comparision:
Reference 2 shows that this is also true for other respiratory diseases (figure 2):
This shows very well that the isolation measures and the social distancing work very well to control such transmissable diseases.
- How coronavirus lockdowns stopped flu in its tracks
- Monitoring respiratory infections in covid-19 epidemics
In addition to Chris' answer above, the effect is even more pronounced in Southern Hemisphere countries where flu season started during the pandemic. The New Zealand lockdown and health response dramatically lowered the prevalence of reported flu-like symptoms.
Reference: Flu Tracking reports - New Zealand - week ending 31-May-2020
Effective public health measures to mitigate the spread of COVID-19: a systematic review
In December 2019, a novel coronavirus (2019-nCoV) was recognized in Wuhan, China. It was characterised by rapid spread causing a pandemic. Multiple public health interventions have been implemented worldwide to decrease the transmission of the 2019 novel coronavirus disease (COVID-19). The objective of this systematic review is to evaluate the implemented public health interventions to control the spread of the outbreak of COVID-19. Methods: We systematically searched PubMed, Science Direct and MedRxiv for relevant articles published in English up to March 16, 2021. We included quasi experimental studies, clinical trials, cohort studies, longitudinal studies, case-control studies and interrupted time series. We included the studies that investigated the effect of the implemented public health measures to prevent and control the outbreak of 2019 novel coronavirus disease (COVID-19).
The database search using the predefined combinations of Mesh terms found 13,497 studies of which 3595 in PubMed, 7393 in Science Direct 2509 preprints in MedRxiv. After removal of the duplicates and the critical reading only 18 articles were included in this systematic review and processed for data extraction.
Public health interventions and non-pharmaceutical measurements were effective in decreasing the transmission of COVID-19. The included studies showed that travel restrictions, borders measures, quarantine of travellers arriving from affected countries, city lockdown, restrictions of mass gathering, isolation and quarantine of confirmed cases and close contacts, social distancing measures, compulsory mask wearing, contact tracing and testing, school closures and personal protective equipment use among health workers were effective in mitigating the spread of COVID-19.
In spring 2020, in response to the COVID-19 crisis, world leaders imposed severe restrictions on citizens’ civil, political, and economic liberties. These restrictions went beyond less controversial and less demanding social distancing measures seen in past epidemics. Many states and countries imposed universal lockdowns. Lockdowns, as we define them here, require people to stay home in some countries and places, citizens must have ad hoc licenses to leave their homes for any reason. Citizens are often forbidden from playing outside, e.g., by jogging alone in the park. Citizens are forbidden from gathering in groups larger than ten, and in some cases they are forbidden from visiting friends and family even in small groups. Lockdowns do not merely prohibit large gatherings, such as conferences or concerts, but also prohibit small backyard parties. Most places of work are ordered to close, resulting in mass unemployment.
In this paper, we argue that these restrictions have not been accompanied by the epistemic practices morally required for their adoption or continuation. While in theory, lockdowns can be justified, governments did not meet and have not yet met their justificatory burdens.
This paper will not attempt to assess or determine which suppression mechanisms governments ought to have imposed, either in light of the information they had or have now. We will not argue that less stringent policies were optimal or better justified. Rather, our goal is to explain how government leaders failed and have continued to fail to meet their epistemic duties. We will argue that states relied upon bad data and flawed models, and they lacked the other kinds of evidence they would need to justify lockdowns. Again, we do not thereby claim that lockdowns were bad policy, nor are we assessing how dangerous COVID-19 is. Instead, we argue that most governments have failed to meet their epistemic duties.
As a partial analogy, imagine the state strongly suspects a person is a dangerous serial killer. Suppose there is indeed some evidence he is. To ensure he does not further endanger the public, they arrest and detain him. Months later, however, he remains in prison, yet the state has not convicted him in fact, it has barely begun to collect the evidence it needs to demonstrate his guilt. Moreover, suppose we learn that the state has made demonstrable errors in its reasoning in accusing the person of the killings. Here, civil rights lawyers might well complain that the state has not met the epistemic obligations needed to hold the prisoner. This does not mean the lawyers necessarily deny the suspect is a killer. They may not even want him set free. But to justify infringing the suspect’s rights, the state needs to be more than factually correct: it needs to have strong epistemic grounds for its claims. For state agents to imprison someone without proper evidence is a severe ethical failing. Note that we are not, in this analogy, claiming that lockdowns are equivalent to imprisonment our point is simply to provide an example where governments are required to possess a certain level of justification before they may restrict citizens’ liberties.
Study shows rapid return of respiratory viruses after COVID-19 restrictions relaxed
Histograms of non-COVID-19 positive respiratory virus tests from January 1, 2019 – May 25, 2021 show notable decline and spikes following the implementation and relaxation of COVID-19 precautions. Symbols Legend: *March 2020 start of pandemic lockdown measures, †May 2020 phase one reopening of Texas, ‡October 2020 additional reopening measures, §March 2021 removal of all COVID restrictions, including elimination of mask mandates
Newswise — HOUSTON-(June 4, 2021) &ndash A new Houston Methodist study shows a rapid return of seasonal respiratory viruses after COVID-19 restrictions were relaxed in Texas, demonstrating the apparent effectiveness of masking, distancing and other precautionary measures at stopping the spread of respiratory illnesses.
This rise in non-COVID respiratory viruses to pre-pandemic levels comes on the heels of Texas ending its mask mandate in early March and lifting restrictions on businesses, which can now operate at 100% capacity. Further contributing to the spike in cases were the updated COVID-19 guidelines from the CDC in mid-May that gave the fully vaccinated license to resume activities without masks or distancing.
Given the immediate community impact of these findings, the report was posted on the preprint server medRxiv. The manuscript, titled &ldquoThe rapid reemergence of seasonal respiratory viruses in Houston, Texas, after relaxing COVID-19 restrictions,&rdquo has also been submitted for peer-review to a medical journal. S. Wesley Long, M.D., Ph.D., medical director of diagnostic microbiology at Houston Methodist, is the corresponding author on the study.
&ldquoThis sharp resurgence we&rsquore seeing of seasonal respiratory viruses in Houston is not surprising now that mask mandates have been lifted in Texas, and other precautions, such as social distancing and occupancy limits in stores, restaurants and events, have been removed.&rdquo Long said. &ldquoReports of non-COVID respiratory viral illnesses surging after COVID restrictions are lifted has been reported in Australia and elsewhere, and we&rsquore now starting to see it happen in the U.S.&rdquo
After noticing a recent cluster of seasonal non-COVID coronavirus infections diagnosed at Houston Methodist, Long and his team pulled the data for the respiratory pathogens in Houston. They found that while rhinovirus and enterovirus infections started to rebound in the fall after the capacity limits for bars and restaurants were relaxed in Texas, the seasonal non-COVID coronaviruses, parainfluenza and even respiratory syncytial virus (RSV) are showing robust increases in cases over the last two months.
The study&rsquos series of histograms illustrates the striking ebb and flow of non-COVID respiratory virus diagnoses in Houston through each stage of precautionary measures being enacted and relaxed. Most notably, cases of parainfluenza, a common virus that can cause respiratory illnesses, such as colds, bronchitis, croup and pneumonia, rose by 424% from March to April, continuing to increase 189% from April through May 25. Seasonal coronaviruses, which usually appear in the winter and tend to decline in March, increased by 211% from March to April and continued to increase in May. Rhinovirus and enterovirus cases increased 85% from March to April, and RSV cases increased 166% by May 25 when compared to April.
Long said these peaks are out of season and have been increasing since Texas removed its final COVID-19 restrictions in March. He notes similar increases have been seen elsewhere, notably RSV in Australia, after COVID-19 measures were relaxed there.
&ldquoFor more than a year, COVID-19 was the primary cause of respiratory illness in the U.S., but now as we relax restrictions, it is important for clinicians to consider other respiratory pathogens may be causing spikes in disease outside of their usual seasonal peaks,&rdquo Long said.
This news is especially concerning to infectious disease experts, as they anticipate many individuals likely decided to opt out of masking and opt in to gathering rather than distancing this past Memorial Day weekend in response to the recent relaxation of governmental guidelines and mandates.
&ldquoThe study clearly demonstrates the utility of masks and social distancing and the effect these non-pharmacologic precautions had on suppressing all respiratory viruses, not just COVID-19,&rdquo he said.
Electronic supplementary material is available online at https://doi.org/10.6084/m9.figshare.c.5368980.
Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
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Diagnostic and Monitoring Tools
SARS-CoV-2 genetic material is reported to be successfully detected through throat swabs and the upper and lower respiratory tract, blood, stool, or urine samples (Pan Y. et al., 2020 Chen W. et al., 2020 Yan et al., 2020). Several methods have been introduced for the detection of SARS-CoV-2. However, the collection of various samples from different sites and the utilization of multiple techniques is usually recommended to avoid false results related to the use of a single sample or method (Wang et al., 2020b). Furthermore, the application of positive, negative, and inhibition controls is also recommended to assure quality diagnosis (Yan et al., 2020).
Nucleic Acid Amplification Tests
PCR and Real-Time PCR
PCR and RT-PCR are considered important molecular biology techniques, first introduced in the 1980s. The techniques are based on the amplification and detection of a particular gene (Panawala, 2017). The amplification of genetic material is beneficial for obtaining the satisfying quantity of specimens required for a laboratory study. Both PCR and RT-PCR involve the utilization of certain enzymes. PCR uses a DNA template, whereas RT-PCR uses RNA (Panawala, 2017). Several RT-PCR-based test kits have also been developed (Li X. et al., 2020).
Sensitivity and Specificity
The techniques are considered highly sensitive, highly specific, and reliable for the detection of CoVs (Shen M. et al., 2020). However, these methods were observed to be commonly used for SARS-CoV-2 detection (Li X. et al., 2020). Yet, the procedures are claimed to be time-consuming and expensive that require costly reagents or equipment. The absence of safe and stable EPC (external positive controls), as available for SARS-CoV-1, is another severe problem in the detection of SARS-CoV-2 (Shen M.et al., 2020). Furthermore, adequate sampling, proper handling of the sample, and sufficient genetic material are recommended for a reliable PCR-based report (Lee et al., 2020). Additionally, RT-PCR is recommended over PCR due to its superior sensitivity (Shen M. et al., 2020).
Several rapid diagnosis kits that have been developed as per WHO standards are claimed to be 95% accurate against SARS-CoV-2. An RT-PCR-based test kit has also been introduced by the Centers for Disease Control and Prevention (CDC) CDC (2020b). Rapid nucleic acid diagnostic papers have also been invented, which provide a rapid detection facility of only 3 min with unaided eye observation (Jin Y. et al., 2020). Furthermore, the kits are only limited to upper and lower respiratory tract specimens. However, FDA has recently authorized the first RT-PCR-based LabCorp COVID-19 kit with a home collection option (FDA, 2020b).
Loop-Mediated Isothermal Amplification
LAMP is known as an ultrasensitive novel isothermal nucleic acid amplificationsed method. It has been claimed to be capable of detecting even a small quantity of biomaterial within an hour and without the need for expensive reagents or equipment.
Sensitivity and Specificity
Its sensitivity and detection rate against coronaviruses have been found to be similar to those of PCR-based methods. However, the technique requires a high temperature, usually 65 ଌ, which restricts its application (Shen M. et al., 2020).
The microarray technique has been widely used for the detection of coronaviruses. In this method, the virus RNA is used to produce cDNA, labeled with a specific probe through reverse transcriptase followed by subsequent detection of that specific probe. The method offers a low cost with sensitivity equal to that of RT-PCR. Moreover, portable microarray chips with adequate detection limits have also been introduced (Shen M. et al., 2020).
Specific High-Sensitivity Enzymatic Reporter Unlocking
This method is based on RNA-targeting CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) related enzyme Cas13. Cas13 has been combined with LAMP to detect DNA or RNA molecules.
Sensitivity and Specificity
The method has been shown to be quick, portable, and highly sensitive for nucleic acid detection (Shen M. et al., 2020 Udugama et al., 2020).
Although the nucleic acid amplification test has been widely recommended for the detection of SARS-CoV-2, its false reports could not be overlooked that may result in a false diagnosis and other severe consequences (Li X. et al., 2020). Consequently, the CT (chest radiography) scan has become a reliable method for the diagnosis of COVID-19 in clinical practice (Jin Y. et al., 2020). The scan images of almost all COVID-19 cases indicate the same features, particularly bilateral pulmonary parenchymal ground-glass opacification and consolidative pulmonary opacities, that have been observed in nearly 60 to 77 percent of cases (Forouzesh et al., 2020). At the same time, it has been observed that patients with negative nucleic acid amplification tests may show positive chest CT scan findings. However, a repeated nucleic acid amplification test is suggested for the final remarks (Forouzesh et al., 2020). Artificial Intelligence (AI) technology has also been used for accurate and instant interpretation of CT images (Jin Y. et al., 2020 Mak, 2020).
Some disadvantages of CT imaging have also been reported, particularly nonselectivity and hysteresis of irregular imaging (Li X. et al., 2020). Moreover, prevention from frequent exposure to radiation, especially for pregnant women and children, is strongly recommended (Forouzesh et al., 2020).
Acute serological responses have been identified in COVID-19 patients (Zhou P. et al., 2020). The serological tests are considered alternative to the nucleic acid test and CT imaging. For this purpose, several colloidal gold immunochromatography assays and other related techniques, kits, and detection methods have been applied and established (Jin Y. et al., 2020 Lee et al., 2020 Li X. et al., 2020 Rashid et al., 2020). The techniques generally target coronavirus immunogenic proteins (S, N, E, and M) and RBD to detect the presence of SARS-CoV-2 related antibodies (Mcintosh et al., 2020). The IgG levels are reported to be usually increased as the IgM levels start decreasing during viral infection (Rashid et al., 2020). IgM antibodies have been detected successfully during the early phases of infection, usually within 3ꃚys, and are claimed to be present even after a month. Similarly, SARS-CoV-2 specific IgG antibodies have been reported to be detected after 4ꃚys of infection period with a peak level after 2 weeks. It has been shown that their levels are related to disease severity a higher level of both antibodies indicates greater severity of the infection. Researchers have also suggested IgA detection for SARS-CoV-2 diagnosis that is related to mucosal immunity usually activated in COVID-19 patients. However, it is considered less specific than IgM and IgG (Lee et al., 2020).
A list of other serological markers has been reported for the prediction of infection severity and prognosis of the disease in patients suffering from COVID-19. Some of these include an examination of interleukins (IL) levels, particularly IL-6, IL-10, and IL-2R, ESR (Erythrocyte Sedimentation Rate), CBC (Complete Blood Count), PT (Prothrombin Time), and levels of liver, kidney, heart, and other related enzymes (Forouzesh et al., 2020).
Although serological tests are regarded as fast, powerful, and easy to conduct, it has been noted that the antibodies' response develops after several days of infection. The CDC does not recommend these tests for the diagnosis of current COVID-19 disease. Moreover, only 70% of their sensitivity is reported even after 4𠄶ꃚys of infection (Centers for Disease Control and Prevention (CDC), 2020a Wang et al., 2020b). The antibodies, IgM, and IgG, against SARS-CoV-2, have been observed to increase progressively with infection (Lee et al., 2020). Thereby, early diagnosis of infection is not possible and may lead to false-negative reports. It has also been reported that a large population has already been exposed to other human coronaviruses, and thus the false-positive response is commonly observed due to a high level of SARS-CoV-2 similarity to other coronaviruses. Therefore, the utilization of multiple serological approaches is recommended for a true report (Lee et al., 2020).
The potential impact of co-infections
Africa shoulders a considerable burden of co-infections. Although HIV-1 and tuberculosis may be the most important infections when considering potentially enhanced COVID-19 disease severity, the high incidence of malaria and helminth infections as well as multiple ongoing outbreaks of Ebola virus disease, Lassa fever, cholera, measles, yellow fever, hepatitis E and chikungunya virus 113 all represent infections with unknown interactions with SARS-CoV-2.
The high prevalence of HIV-1 and tuberculosis in sub-Saharan Africa presents an important but largely unknown challenge for the continent with regard to COVID-19. The urgent question that needs answering is whether individuals with HIV-1, or those with past or current tuberculosis, have a higher risk of infection or greater morbidity and mortality from COVID-19. Of the 37.9 million people living with HIV-1 globally, 25.6 million live in sub-Saharan Africa, and it is estimated that 64% are accessing antiretroviral therapy and 54% are virally suppressed 114 . Although individuals who are immunocompetent with well-controlled HIV-1 infections may be at no greater risk for COVID-19, there remains a considerable number of individuals with low CD4 counts and uncontrolled HIV-1 viraemia who may be at risk of severe disease. To date, there have been two published reports of concurrent COVID-19 and HIV-1 infection 115,116 . Although the cohort was an extremely limited group of patients predominantly established on antiretroviral therapy, the pattern of clinical disease did not differ from that observed in the general population, but more research is needed to confirm this result.
The severity of other respiratory infections concomitant with HIV-1 may provide some clues: although the immunopathogenesis of SARS-CoV-2 is probably distinct in several aspects from influenza viruses, there are some shared clinical features. HIV-1 infection is associated with a greater susceptibility to influenza virus infection, increased severity of influenza-related disease and poorer prognosis in patients who are severely immunocompromised 117 . A large South African study observed an eightfold higher incidence of influenza virus infection and a fourfold greater risk of death in the case of HIV-1 co-infection 118 . Paradoxically, there is also evidence that lower inflammatory responses in individuals who are immunocompetent and infected with HIV-1 may lead to milder influenza-related disease 117 . In addition to altering the clinical course of disease, HIV-1 infections may result in poorer antibody responses that may lead to prolonged viral shedding, thereby influencing disease transmission 119 . Tuberculosis, a disease that causes chronic lung damage, may also present a challenge in the COVID-19 era. There were approximately 2.4 million new cases of tuberculosis in Africa in 2018 (ref. 120 ). In a South African study of patients who were hospitalized for severe respiratory illness, those with influenza virus infection together with laboratory-confirmed tuberculosis had a 4.5-fold greater risk of death 121 . HIV-1 largely drives the tuberculosis epidemic in sub-Saharan Africa, and the ‘triple-hit’ of HIV-1, tuberculosis and SARS-CoV-2 infection is consequently of considerable concern.
A preliminary study suggests that HIV-1 infection increases the risk of mortality from COVID-19 by 2.39-fold, and this increased risk seemed to be independent of suppressed HIV-1 viral load due to antiretroviral therapy. Individuals with current tuberculosis had a 2.7-fold greater risk of death 122 . These figures represent a modest increased risk compared with older age and co-morbidities such as diabetes in the same population, which suggests that HIV-1 and tuberculosis may not be considered major risk factors for COVID-19. Although this would be considered good news, further studies are awaited to confirm these initial observations.
The two main potential issues for using SARS-CoV-2 vaccines in individuals infected with HIV-1 are safety and efficacy. However, potential safety issues are likely to be restricted to use of certain vaccine modalities, such as live-attenuated or replicating vaccines, in individuals who are highly immunosuppressed. When considering vaccine efficacy, the magnitude and durability of immunity in individuals infected with HIV-1 for both vaccination against and natural infection with SARS-CoV-2 is unknown. To date, there are no reports describing immune responses to SARS-CoV-2 in individuals infected with HIV-1. It is possible that individuals with HIV-1 may have incomplete immune reconstitution and impaired immunity that may influence vaccine safety and efficacy, even if they are receiving antiretroviral therapy, owing to persistent immune activation and incomplete recovery of T cell and B cell immunity 123,124 . Suboptimal neutralizing antibody responses have been described following immunization against influenza virus or other pathogens in individuals infected with HIV-1 (ref. 125 ). Weaker antibody responses and lower influenza virus-specific memory B cell responses in individuals infected with HIV-1 were directly related to CD4 counts 126 . It will be important to test candidate vaccines for their ability to generate immune responses in a range of high-risk groups, including patients with HIV-1. Several strategies may improve the magnitude and durability of vaccine responses in individuals infected with HIV-1, such as higher doses, booster immunizations and/or the use of adjuvants 127 . Substantive data on the clinical and immunological interaction of HIV-1, tuberculosis and COVID-19 will emerge from Africa in time for improved strategies to guide clinical management of patients who are co-infected and the vaccine regimens.
Finally, an important additional point to note is the indirect effects of COVID-19 on health in Africa within the setting of a high burden of infectious diseases. The WHO estimates that the disruption in vaccination due to disruption in supply could put 80 million infants at risk of contracting vaccine-preventable diseases 128 . Several countries have reported reduced uptake of tuberculosis testing, and patients failing to collect tuberculosis medication or antiretroviral therapy owing to overwhelmed health-care systems, lockdown interventions and public fear of contracting COVID-19 (ref. 129 ). Mitigating these interruptions in prevention, diagnosis and treatment, and ensuring that essential health services continue, will ultimately lower the overall impact of the COVID-19 pandemic in Africa.
Expert reaction new restrictions and the new UK SARS-CoV-2 variant
The Prime Minister and the Chief Medical Officer made a statement on Saturday about new Tier 4 restrictions, the new SARS-CoV-2 variant and updated guidance over Christmas.
Quotes sent out on Wednesday 23rd December 2020:
Prof David Heymann, Professor of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, said:
“Here’s what needs to be done from a global perspective to better understand the mutations (from the report of the WHO STAG-IH yesterday):
1. Continued epidemiological analysis of age, occupation, and other characteristics of those infected with the new virus strain including the natural history of infection, paying close attention to infections in individuals with a history of prior COVID-19 and infections in individuals who have been vaccinated.
2. Neutralization studies of the new variant with sera from vaccinees and from those who have history of previous infection.
3. Activation of regional laboratory networks to support countries in genetic sequencing and associated sample shipment networks
4. Support for evaluation of diagnostic test performance and raising awareness among all diagnostic labs that changes in assay sensitivity or failure to detect all targets in an assay should raise suspicion of emergence of a new variant.
5. Continued facilitation of virus sharing among countries.
6. Encouragement of continued study of vaccine efficacy and therapeutic performance including monoclonal antibody preparations and antivirals.”
Prof Ian Jones, Professor of Virology, University of Reading, said:
“Most coverage assumes that the new variant is a worse variant, but at the moment we don’t know if that is the case. The data is consistent with an increased rate of transmission but whether the outcome of infection is altered is not yet clear. A shift to the upper respiratory tract could mean less lower respiratory tract infections, which is where the damage is done, or the maintenance of the current morbidity rates but with a virus that’s easier to catch. Only the monitoring of infection outcomes by the new variant will resolve this. Infection still requires close contact so the rise in case numbers undoubtedly involves non-compliance with distancing measures as well as any change in the virus. The new variant warrants attention but, as we’ve just seen, the consequence of assuming the worse is not without wider consequences, which are themselves detrimental to society.”
Dr Jonathan Stoye, Group Leader, Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, said:
“The response to the new variant has generated a much greater reaction than the previous report of the D614G mutation which arose several months ago and has clearly been shown to increase virus growth rates. Perhaps the heightened response this time around reflects a growing anxiety about the increasing virus spread. In reality, little about how the virus spreads between people has changed. Viruses will always evolve and selection for growth advantage will follow but spread can still be prevented by following the basic principles of hygiene and distancing.”
Prof Liam Smeeth, Professor of Clinical Epidemiology, and Dean of the Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, said:
“It is true that RNA viruses do very frequently mutate and most mutations have no consequence for how the virus behaves or what measures we need to take, the variant we are now seeing in the South East of England does seem to show differences in how the virus behaves. There is pretty strong evidence it is more infectious, so passes between people more easily, and thus spreads more quickly. This means that low level social distancing measures will be less effective, and to control the spread tighter measures are needed. In effect, the natural R number of the new variant will be higher, so to get this below 1 will need greater efforts to control spread. The policy steps taken – Tier 4 and the Christmas restrictions – are, sadly, an appropriate and much needed response.
“The VERY good news is that there is nothing to suggest the existing vaccines will be any less effective against the new variant. The priorities remain. These are firstly everyone uniting in collective action to control the spread and limit the damage done by uncontrolled transmission of the virus. While painful and difficult for everyone, a short period of tighter restrictions now will prevent the devastating effects of uncontrolled spread. This will speed up how quickly we can get on top of this virus and allow our social and economic lives to return to some kind of normality.
“Secondly, to roll-out vaccination as quickly as possible. The MHRA, our world leading regulator, has undertaken a rigorous process to ensure the vaccine is safe, and continues to monitor safety very closely. I urge everyone who is offered the vaccine to have it: this will protect themselves but also protect those around them and indeed the whole of society. Achieving a high level of uptake of the vaccination provides a route out of this terrible pandemic for all.”
Quotes sent out on Monday 21 December 2020:
Prof Saad Shakir, Director, Drug Safety Research Unit said:
“Reduction in the efficacy of medicines used to treat COVID-19, such as dexamethasone and remdesivir, is unlikely. However, the effects of the new variant on products that use antibodies or monoclonal antibodies need to be evaluated.
“When it comes to the efficacy of the vaccines, assertions have been made by the Chief Medical and Scientific Officers in the UK that the changes in the spike protein of the new variant are unlikely to reduce the protective effect of COVID-19 vaccines. Since the three vaccine forerunners target the spike protein, how the variant responds to the vaccines and the protection that the vaccine will offer does still need to be examined in detail and scientists are working round the clock to answer these questions. Scientists at the research facility in Porton Down in the UK are growing the variant virus and will examine the interaction between the vaccines and the virus. Studies (cluster clinical trials or epidemiological studies) to examine this question in vaccinees will take much longer.
“Everyone should vaccinate with COVID-19 vaccines if they are fortunate to be invited unless they are advised not to do so by a healthcare professional.”
Prof Brendan Wren, Professor of Microbial Pathogenesis, London School of Hygiene & Tropical Medicine, said:
“The COVID-19 Genomics UK (COG-UK) consortium have done an excellent job in identifying and tracing the routes of transmission of the 501Y variant. It is doing the job it was set up to do, and few countries worldwide are using such forensic approaches to identify new variants as they arise. There are likely many SARS-CoV-2 variants worldwide that remain undetected and it may well be that the 501Y variant did not arise in UK. The consequences of the highlighting the 501Y variant is that the UK may be treated as the lepers of the world with further travel chaos and detrimental social and economic consequences. The UK may be victims of their own technical success in highlighting the emergence of the 501Y variant.”
Dr Shaun Fitzgerald, Royal Academy of Engineering Visiting Professor at the University of Cambridge, said:
Comment on the travel ban:
“We know it is really important to limit travel and social mixing in order stop the transmission dead in its tracks. It is completely understandable that travel bans to other countries are being imposed. The key question is not whether this is right or wrong, but whether this is soon enough. Let’s look back 12 months. If travel bans had been imposed much sooner and more rigorously, what would have happened? Clearly we’ll never really know but it is likely that the overall impact by now of SARS-CoV-2 would have been lessened.
“The lesson again is that we can’t act too soon or too hard to stop this virus and its variants. The ‘short sharp shock’ treatment to intersect the transmission pathways is what we need.
“When it comes to the various interventions that stop transmission pathways, we must not kid ourselves about the definition of ‘short’ – it is a relative timeframe not an absolute one. So short can in fact be many months – but notably shorter than trying to bolt the door after the horse has left.”
Prof Mark Harris, Professor of Virology, University of Leeds, said:
“Of course we should all be concerned about the emergence of a new and distinct variant of SARS-CoV-2. However, it is important to point out that it is still the same virus, causing the same disease. The mechanism by which it is transmitted is also the same, but the genetic changes in this variant appear to enable it to transmit more efficiently, although the biological explanation for this increased rate of transmission remains to be determined. So the key messages to prevent transmission are the same – limit the number and size of gatherings, maintain social distancing, wear masks in public areas, wash hands frequently etc. The virus can only mutate into new variants when it infects people, so reducing the number of infections will also decrease the potential for variation.
“Unfortunately, the new variant has also become a political football. It is being blamed by this Government for the rapid spread of the virus in London and the South-East – this is a smokescreen to distract from the failure to put these areas into Tier 3 after the national lockdown. The lockdown did not reduce the numbers of infections sufficiently to justify returning to Tier 2 where (for example) up to 2000 people could attend an outdoor sporting event. The potential for virus spread of such communal activities is enormous and the rapid increase in cases of the new variant are a direct consequence. We need to learn from the lessons of the past year and recognise that by delaying and failing to act decisively our efforts to control the pandemic are less effective, and ultimately lives are at risk.
“The travel ban is of course justified by trying to prevent the spread of the new variant to other countries, and indeed it will be an effective control measure in that regard. We learnt very early during the pandemic that air travel played a key role in the rapid global spread of the virus, and unfortunately then we did not act quickly and decisively enough to prevent that spread.”
Quotes sent out on Sunday 20 December 2020:
Dr Jeffrey Barrett, Director of the SARS-CoV-2 Genomics Initiative at the Wellcome Sanger Institute, said:
Comment in response to questions about the new variant and the PCR test:
“One of the mutations in the new variant deletes six bases in the viral genome that encode amino acids 69 and 70 of the spike protein. By coincidence, this region is one of three genomic targets used by some PCR tests, and so in those tests that “channel” comes up negative on the new variant. However, the other two channels, which are not affected by the new variant, provide redundancy, and mean that the virus is still detected by the combined test. I’m not aware of any commercial tests that use just one target in this part of the viral genome, but if there are, they should be carefully investigated.”
Dr Robert Shorten, Chair, Microbiology Professional Committee, Association for Clinical Biochemistry & Laboratory Medicine (ACB):
Comment in response to questions about the new variant and the PCR test:
“Some of the PCR (swab) tests detect part of the spike protein gene that has recently been reported to have mutated. This has affected the ability of some tests to detect the virus. Laboratories know which genes their tests target and are vigilant about checking for test performance. PCR tests would generally detect more than one gene target so a mutation in the spike protein would not affect detecting other viral gene targets, which mitigates the risk of reporting a false negative result. All viruses mutate and vigilance and quality systems used by diagnostic laboratories is always important.”
Dr Stephen Griffin, Associate Professor in the School of Medicine, University of Leeds, said:
“The new SARS2 variant may well be cause for significant concern, and all the more reason to be vigilant. However, that it has taken an event of this nature to provoke a reaction from the government says more about the current scenario in the UK and the long term view of how this came to be, rather than the naturally upsetting and disappointing false promises over Christmas that have now been revoked.
“It is clear that failure to make good on the sacrifices made during the first lockdown, suppress infection rates over summer, and replace the failed corporate TTI system has led directly to the resurgence seen since September, the need for a second (and likely a third) lockdown, and ultimately an environment in which SARS-COV-2 is able to thrive and evolve. Half-baked policies neither restore socio-economic harms, nor suppress infections, and the reactionary, fragmented and confusing implementation of Tiers along with their obscure criteria has led to public favour eroding day by day. We are left at the mercy of misinformation and fringe viewpoints.
“Nevertheless, if it takes the new variant to finally convince our leaders to implement an effective suppression strategy along with the long-recommended safeguarding on TTI, quarantine and internal travel, then so be it. We cannot simply stand by and wait for vaccines to rescue the situation, the human cost has already been far too high.”
Prof Paul Hunter, Professor in Medicine, The Norwich School of Medicine, University of East Anglia, said:
“The suggestion that the variant arose in a chronically infected individual is plausible but unless we have sequences from that individual it would be difficult to prove.
“It is known that viral variants are more likely to arise in people who are chronically infected, though the evidence for this primarily comes from those viruses that routinely cause chronic infections such as HIV and Hepatitis B. Indeed in these infections the generation of what are known as immune escape mutants are an important part of how the virus may cause continuing disease. We do know that in immunocompromised patients SARS-CoV-2 can shed COVID for quite a long time 1 , but so can immunocompetent patients 2 . Also we do know that mutations in SARS-CoV-2 are more likely to occur in chronically infected immunosuppressed individuals as referred to in the paper by Rambaut and colleagues 3 .
“Nevertheless mutation in viruses are a random event and the longer someone is infected the more likely a random event is to occur. So Rambaut and colleagues’ suggestion the this variant arose in a chronically infected individual is highly likely and that any person chronically shedding the virus is more likely to be immunosuppressed is also highly likely. But, we may not be able to provide this for certain.”
1. Aydillo T, Gonzalez-Reiche AS, Aslam S, van de Guchte A, Khan Z, Obla A, Dutta J, van Bakel H, Aberg J, García-Sastre A, Shah G. Shedding of Viable SARS-CoV-2 after Immunosuppressive Therapy for Cancer. New England Journal of Medicine. 2020 Dec 1.
2. McKie AM, Jones TP, Sykes C. Prolonged viral shedding in an immunocompetent patient with COVID-19. BMJ Case Reports CP. 2020 Oct 113(10):e237357.
Dr Jeffrey Barrett, Lead Covid-19 Statistical Geneticist, Wellcome Sanger Institute, said:
Regarding the number of mutations of the new variant:
“Our virological post 1 lists the 17 non-synonymous, or coding, mutations. These are ones that change the protein sequence of one of the viral genes. There are also a couple of synonymous (sometimes called “silent”) mutations that don’t have any function, but crop up and come along for the ride. So I think Patrick Vallance was counting the total number, whereas the biological investigations are really focused on just the coding changes.”
Prof Sheila Bird, Formerly Programme Leader, MRC Biostatistics Unit, University of Cambridge, said:
“The priority given to genomic analysis of samples from Tier 4 regions may have changed in December 2020 to prioritize investigation of novel variants. This would be a cogent response to the current public health emergency but might mean that limited capacity for genomic analysis had to be re-assigned in non-Tier 4 regions. Hence, the following questions arise:
“1. What percentage of SARS-CoV-2 cases is subject to genomic analysis (Scotland’s press conference suggested 5% to 10%).
2. What is the typical lag between swab-date for SARS-CoV-2 positive cases & genomic analysis-date for samples sent for genomic analysis? (Scotland suggested weeks, not days).
3. What increase in sampling fraction was made for Tier 4 regions as concern mounted about the novel virus? (this would be scientifically-efficient).
4. What change, if any (including decrease), was made in sampling fraction outside of Tier 4 regions?
5. What acceleration in throughput of genomic analyses was made for Tier 4 regions as concern mounted about the novel virus? (this would be warranted scientifically & for public health).
6. What change, if any (including deceleration), was made in throughput of genomic analyses outside of Tier 4 regions?
7. Did No10 press conference slides refer always to swab-date?
8. If not, which dates are used on which slides?”
Dr Julian Tang, Honorary Associate Professor/Clinical Virologist, University of Leicester, said:
“Regarding the N501Y mutation within the new B.1.1.7 lineage, part of the 20B/GR SARS-COV-2 clade, which was already defined in this earlier paper (Fig 1):
“An examination of the global GISAID SARS-COV-2 sequence database shows that this N501Y mutation was actually circulating, sporadically, much earlier in the year outside the UK: in Australia in June-July, USA in July and in Brazil in April, 2020.”
“Whether or not these viruses were brought to the UK and Europe later by travellers or arose spontaneously in multiple locations around the world (in response to human host immune selection pressures) requires further investigation.”
Prof Peter Horby, Professor of Emerging Infectious Diseases, Centre for Tropical Medicine and Global Health, University of Oxford, said:
“The conclusion of increased transmissibility is based on various sources of converging data, including, but not limited to, the rate of change in the frequency of detection of the variant (the growth rate) and the correlation between R-values and the frequency of detection of the new variant.”
Quotes sent out on Saturday 19 December 2020:
Prof Julian Hiscox, Chair in Infection and Global Health, University of Liverpool, said:
“Coronaviruses mutate all the time so it is not unexpected that new variants of SARS-CoV-2 are emerging, we see this all the time in other human and animal coronaviruses. We have great systems in place in the UK to identify these variants to inform a public health response. The most important thing is to investigate whether this variant has any new properties that impact on human health, diagnostics and vaccines. We need robust mechanisms in place to do this.
“The control measures are appropriate – better to be cautious. Stopping the spread of this virus is simple: people need to follow and obey the guidance of the Tier system and have common sense. The more people you come into contact with, the more chance of spreading. So avoid social mixing – it’s not long to wait for the widespread roll-out of the vaccine.”
Dr Julian Tang, Honorary Associate Professor/Clinical Virologist, University of Leicester, said:
“Regardless of this new 501Y virus variant, from a purely virological/epidemiological viewpoint, the new restrictions over Christmas and the new Tier 4 for the hardest hit London/Southeast areas are a necessary measure to control this virus.
“But unfortunately, even mixing amongst 3 households (with as many as 10-15 people) in the other Tiers, over 6-8 hrs on Christmas Day, is more than enough to spread this virus – and it is likely that many more people are now going to do this, now that the opportunity is limited to just one day.
“So I would still urge people to restrict the duration and number of households mixing, open the windows (even just halfway) to protect the elderly – including asking them to maintain social distance as much as possible within the house, and to mask when not eating/drinking.
“If this new 501Y virus variant really is more transmissible, then even brief exposures may still result in infection.”
Dr Shaun Fitzgerald, Royal Academy of Engineering Visiting Professor at the University of Cambridge, said:
“The situation at present is extremely concerning and we are on a precipice. That’s why hard decisions about Christmas have to be made. If households do mix on Christmas Day, there is even more reason to be absolutely fastidious about the measures we can all take to help reduce the risk of transmission.
“We know how this horrible virus spreads, and we all need to disrupt the pathways. Hands, face, space, ventilation – and limit our social interactions. 3 households is a maximum, not a target. Just like speed limits – it’s safer to go below them.”
Prof Peter Openshaw, past-President of the British Society for Immunology and Professor of Experimental Medicine at Imperial College London, said:
“The information that the government has just issued about this new variant coronavirus is of great concern. It is right to take it seriously although there are only 23 mutations in the genetic code of 30,000 nucleotides the variant does seem about 40-70% more transmissible. The doubling time is now at just 6 or 7 days so it is really vital that we get this under control.
“The spread of this new variant has been associated with an increase in hospitalization, especially in Kent and London however, there is no evidence at the moment that the new variant causes disease which is any different from that caused by previous variants.
“It is a tribute to the genomic surveillance by COG-UK that the variant has been detected so quickly. The reasons for the enhanced infectivity are not yet clear. We need to know if it is due to more viral replication or better binding to the cells that line the nose and lung. There is currently no direct evidence that the virus is able to evade immunity generated by past infection or by vaccination, but there is good reason to think it won’t. All this needs to be investigated.
“It is also remarkable that 350,000 people have already received the first dose of the Pfizer/BioNTech Vaccine. It is vital that vaccination is ramped up as fast as possible to control the effects of infection on the most vulnerable, and to get front-line workers protected. I absolutely urge everyone being offered vaccination to get vaccinated.
“This holiday period is important to all of us and we are all devastated to hear this news. However, now is the time to reunite in the fight against the virus rather than arguing between ourselves. Let’s enjoy Christmas as best we can, and celebrate again in the spring and summer when we hope all this will be over.”
Dr Jeremy Farrar, Director of Wellcome, said:
“The new strain of Covid-19 is highly concerning and it is right to act with urgency as the government has done. The changes announced deserve all our support.
“Research is ongoing to understand more, but the infection rate is clearly rising very rapidly, particularly in London and the south-east of England. The data shows the new strain is more transmissible and has led to more infections and a worrying increase in the r-rate.
“At the moment, there is no indication that this new strain would evade treatments and vaccines. However, the mutation is a reminder of the power of the virus to adapt, and that cannot be ruled out in the future. Acting urgently to reduce transmission is critical.
“Difficult as this year has already been, we must stay humble. There are still many unknowns about Covid-19 and it remains a grave threat to us all.
“There is no part of the UK and no country globally that should not be concerned. As in the UK, in many countries the situation is very fragile.
“It may feel harder during times we normally celebrate and enjoy with family and friends, but we must keep doing all we can to stay safe.
“We will only end this pandemic with a combination of vaccines, tests and treatments, available to everyone, everywhere. The pace of global research has been phenomenal and we have made significant progress on the tools needed. However, we must be realistic this pandemic is not over and it will take some time for the first vaccines to have the impact needed.
“Through 2020 much of this pandemic has been predictable, waves of infection reverberating globally as behaviour changes and restrictions are relaxed. We may now be entering a less predictable phase as the virus evolves and changes.
“We must keep asking ourselves ‘are we doing enough’ and responding fast to new and continued challenges, in order to save lives now and as we move into 2021.
“Only tighter restrictions can curb infection rate rises and we have to reduce transmission to prevent hospitalisations and deaths. We must pay tribute to healthcare workers and global research community everywhere, working tirelessly on behalf of all of us. We owe them all our thanks and support and to be willing to take every precaution.”
Dr James Gill, Honorary Clinical Lecturer, Warwick Medical School, said:
“Hearing that the Tier 4 restrictions have been initiated in the south of the country is obviously going to be a shock and a disappointment. In the early stages of the COVID19 outbreak, criticism was directed at the slow pace of response and distinct action which will have been a contributing factor to the degree of COVID19 spread over the past year.
“Viruses change, there have been observed changes previously in COVID19 and countries have been affected by different strains, but crucially these strains have not resulted in any relevant clinical changes such as new symptoms. We have been able to detect and act on this new variant due to exceptional work going on in labs across the country that have been tasked to monitor the genetic code of the COVID19 virus – specifically watching for this eventuality, the rise of a new variant. With the latest variant, we are seeing an increase in infectivity, and it appears this latest COVID19 strain is one of the main driving factors in the rise in cases in the South. Thus it is correct, prudent and sensible to act now as we learn more.
“We are still waiting to learn further about this new strain, and that has to be the key information here, it appears to be more contagious but we do not know if it is more or less dangerous. Hence the stronger restrictions are sensible. The greater curbs on social interactions – even at Christmas – allow time for scientists to learn and characterise this new strain, and in doing so, prevent the repeat of mistakes that were made in the earlier stages of the pandemic.
“Being reactive with a virus is very difficult. Whilst an over-used phrase, it is shutting the door after the horse has bolted. In this current situation being proactive, taking very strong steps, is the right thing to do. To be very clear, delaying introduction of new restrictions whilst we gather further data on this new strain will cost lives. When scientists have a clearer picture of the clinical relevant changes that are present in this strain, we will be able to safely review our restrictions.
“Science and medicine is driven by data. To act without being guided by data is foolish at best, dangerous at worst. Currently the data are suggesting a rise in new infections as a result of this new strain, so it is sensible to instigate restrictions to gather new data.”
Prof John Edmunds, Professor in the Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, said:
“There are 3 key questions that need to be addressed when a new strain emerges: is it more pathogenic? Is it different enough to evade the immune response generated by previous infection or vaccination? And is it transmissible?
“At present we have no information on the first two questions, but over the last few days we have begun to get an answer for the third and the answer is very bad news. It looks like this virus is significantly more infectious than the previous strains. This means that to control it we are going to have to put in place much more restrictive measures. I am sorry to say that it looks like there are tough times ahead, but the faster and more decisively we act the quicker we can begin to control this new virus.”
Prof Jonathan Stoye, Group Leader, Retrovirus-Host Interactions Laboratory, The Francis Crick Institute, said:
“I’m not certain that I understand the rationale of a partial imposition of Tier 4 rules. If enhanced restrictions are required to control the spread of the variant, why aren’t they being imposed across the whole country? If the variant virus arose only once and, because of a genuine increase in enhanced transmissibility, spread to the 50% we see in the Southeast under Tier 3 rules, how can we be confident that in the next few weeks the reported 5% incidence in other parts of the country will not rise to 50%? Better to act sooner than later!”
Prof Paul Hunter, Professor in Medicine, The Norwich School of Medicine, University of East Anglia, said:
“Today’s press briefing was perhaps not too surprising. We did hear more information about this new variant SARS-CoV-2 virus. We were told by Sir Patrick the following important points
- There has been very dramatic increase in cases and hospitalisations in London and the South East relative to the rest of England in the past days and this increase does seem to be caused by the new variant.
- The new variant is not just due to a single mutation and there are some 23 different mutations many of which are associated with the Spike protein that the virus used to get into cells.
- The variant is thought to have occurred sometime in September in London or Kent.
- That the virus variant is substantially more infectious is clear from the fact that in early November it was responsible for 28% of infections in London and in the week ending 9th December it was responsible for 62%. The PM said that early analyses suggest that the new variant seem to be 70% more infectious and to have increased the R value by 0.4 or more.
- Currently there’s no evidence it causes more severe disease. At present the current vaccine should still be effective.
- There is also some suggestion that the new variant is spreading elsewhere. Indeed, if you look at the Dashboard data for the South West, East Midlands and West Midlands it does look like cases are starting to increase there as well.
“That viruses mutate to become more infectious is not surprising and that this could happen with new and emergent viruses has been known for some time.
“To me these reports on the transmissibility of the new variant are even more depressing than I had anticipated. An increase in R of 0.4 or greater is extremely bad news. During the national lockdown in November the best we could achieve was an R value of somewhere between 0.8 and 1.0 around the UK. What this means is that even if we went back to the National Lockdown it would still not be enough to bring the R value down to less than 1.0. It is even uncertain whether if we went back to the lockdown of March and April we would bring the R value down to less than 1.0. So, perhaps, all we can now hope for is that the epidemic increases less rapidly with the measures that the PM announced today.
“Although the vaccines should still be as effective as reducing the risk of severe disease in death in people vaccinated. The increased transmissibility reported today does mean that even with some benefit from vaccine on reducing transmissibility, the vaccination programme is even less likely to protect those people who choose not to be vaccinated.
“It is inevitable that this new variant will spread throughout the UK and we can expect to see increased transmission rates in all regions and devolved administrations over coming weeks. As yet I know of no evidence that the new variant has spread overseas but I suspect that this is only a matter of time and we will see similar problems in other countries from this new variant.
“The appearance of such an infectious variant of the virus at this time of year represents a perfect storm for the epidemic and is desperately bad news for attempts to control the epidemic.”
Dr Michael Head, Senior Research Fellow in Global Health, University of Southampton, said:
“The escalating case numbers mean that dramatic interventions are essential, so the new announcements are important and will help to provide some element of control on the national landscape. However, it has been obvious for some time that mixing of multiple households over the Christmas period will lead to a very difficult January. Therefore, this level of restrictions is what should have been implemented at the time of the previous Christmas announcements, regardless of the impact of this new variant.
“There are several other countries that have strong measures in place over Christmas, and there is plenty of precedent where large public festivals that have been cancelled or curtailed due to COVID-19, such as the Hajj in Saudi Arabia being scaled right back, and a ban on household mixing during Passover in Israel.”
Dr Jeffrey Barrett, Director of the Covid Genomics Initiative at the Wellcome Sanger Institute, said:
“This new variant is very concerning, and is unlike anything we have seen so far in the pandemic. The new restrictions announced today are an entirely justified response to the rapidly developing situation. Detecting new variants like this is one of the key missions of the Covid-19 Genomics Consortium in the UK. The high level of genomic surveillance we have had to date has helped detect and respond to this variant as quickly as possible. We will continue to monitor this and other variants in the weeks and months to come.”
Dr Simon Clarke, Associate Professor in Cellular Microbiology at the University of Reading, said:
“Viruses mutate constantly. The coronavirus has mutated many times over the last year. This helps scientists to track how infections are spreading. For example, we know that most of the infections in the UK in the first wave came not directly from China but from Europe, where a new variant emerged that was different from the strain in Wuhan.
“Government scientists have identified now that there are 17 linked mutations in the genetic code of the virus that seem to make this new strain more infectious. It has been suggested that changes to the virus surface spikes may allow it to bind onto cells more easily. However there isn’t evidence yet that the new virus is more or less dangerous in terms of its ability to cause disease. Sadly, we will have to wait and see if hospitalisations and deaths increase or decrease to find out.”
Prof Daniel Altmann, Professor of Immunology, Imperial College London, said:
“From the graphics as presented, this variant sequence has certainly become more prevalent in the southeast, correlating with an upturn in caseload. As far as I can see this greatly strengthens the case for all to get vaccinated as soon as possible: the vaccines induce neutralising antibodies to several parts of spike (‘epitopes’) and most of these would be unchanged by the mutations – so the vaccines will still work.”
Prof Ravindra Gupta, Professor of Clinical Microbiology, University of Cambridge, said:
“The news, although disappointing for many, is the most appropriate given the speed at which the new variant has spread. The variant has a number of concerning mutations that mean we should control transmission through social restrictions whilst we work to learn more about the impact of these mutations on how the virus behaves. We should seriously consider regional targeting of the vaccine to control spread.”
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COVID-19 lockdowns could lead to social unrest, according to new research
Credit: Pixabay/CC0 Public Domain
An academic from Queen Mary University of London has published a research paper which explores the impact of lockdowns in response to COVID-19 in Africa.
Written by Dr. Roxana Gutiérrez-Romero and published as part of Queen Mary's Center for Globalization Research (CGR) working paper series, the findings are drawn from data incorporating 24 countries. The results show that the probability of riots, violence against civilians, food-related conflicts, and food looting has increased since lockdowns.
The analysis used georeferenced data for 24 African countries with monthly local prices and real-time conflict data reported in the Armed Conflict Location and Event Data Project (ACLED) from January 2015 until early May 2020.
According to the study, although the recently implemented social distancing measures and lockdowns might curb the spread of the coronavirus, an issue of major concern is the potential risks of social unrest given the sudden loss of jobs and livelihoods.
Stricter lockdowns increase chances of riots
The research showed no evidence that early social distancing measures, such as banning some international flights, fuelled conflicts. However, the more strict local lockdowns have increased the chances of riots, violence against civilians and food-related conflicts in the African countries analyzed.
According to the study, increases in food prices are a key driver in the violence against civilians particularly in areas with more cultivated land where rebel groups typically seek resource appropriation from civilians, whenever there is a major shock to food supply.
The research also showed that African countries which have provided a higher number of welfare and labor anti-poverty policies, are less likely to experience riots, violence against civilians and food-related conflicts.
Earlier studies have found that providing aid can in fact increase and extend conflicts as rebel groups might sabotage these programs to prevent weakening their ability to recruit future members from the community.
Dr. Roxana Gutiérrez-Romero, Reader in Quantitative Methods and Policy at Queen Mary said: "The literature has offered quite mixed findings on whether aid and anti-poverty projects can reduce the probability of reducing conflict. These results suggest that conditional-cash-transfers can be successful in reducing conflicts. Countries with a broader net of COVID-19 economic support, with more initiatives, are reducing the most the probability of experiencing conflicts and associated fatalities."
Support required in the long term
From the analyzed African countries with COVID-19 welfare and labor policies, around 70 percent have implemented cash-transfers and 30 percent provided relief in paying utility bills. Only a small minority have implemented labor initiatives.
"As the lockdowns start to ease, the support available to vulnerable people needs to continue, and should also include support for the large informal labor market. This should be a key priority especially considering nearly 277 million people in Africa, one in every five, were already suffering from severe food insecurity right before the pandemic," added Dr. Gutiérrez-Romero.
'Hard winter' ahead
However, Covid would be able to cause an infection again once the cold had passed and the immune response calmed down.
Dr Murcia said: "Vaccination, plus hygiene measures, plus the interactions between viruses could lower the incidence of Sars-CoV-2 heavily, but the maximum effect will come from vaccination."
Prof Lawrence Young, of Warwick Medical School, said human rhinoviruses, the most frequent cause of the common cold, were "highly transmissible".
He added that this study suggests "that this common infection could impact the burden of Covid-19 and influence the spread of SarsCoV2, particularly over the autumn and winter months when seasonal colds are more frequent".
Exactly how all this settles down in future winters is still unknown. Coronavirus is likely to still be around, and all the other infections that have been suppressed during the pandemic could bounce back as immunity to them wanes.
Dr Susan Hopkins, from Public Health England, has already warned of a "hard winter" as a result.
"We could see surges in flu. We could see surges in other respiratory viruses and other respiratory pathogens," she said,