Rapid roll out of SARS-CoV-2 antibody testing—a concernBMJ 2020; 369 doi: https://doi.org/10.1136/bmj.m2420 (Published 24 June 2020) Cite this as: BMJ 2020;369:m2420
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Incorporating hepatitis and HIV testing with Covid-19 antibody surveillance: Enhancing value in global viral infections
We note the concerns expressed regarding antibody testing for Covid-19 antibody. However, it could be possible to enhance the value of testing. The Covid-19 pandemic has exposed fault lines in public health surveillance. To monitor the epidemic, the United Kingdom Government has procured upward of 10 million tests. In Germany, five million serological tests a month are envisaged. Many countries may similarly employ anti-SARS-CoV-2 testing, widening the scope of population level testing. Seroprevalence testing will inform interventions through different periods of the epidemic; two stage cluster sampling can assess community transmission and reduce modeling uncertainties.1 Anti-SARS-CoV-2 testing is not, however, a rapid, direct tool to detect active infection for contact tracing to interrupt chains of transmission of Covid-19.2 Neither does a positive anti-SARS-CoV-2 test obviate precautionary measures or provide incontrovertible proof of durable immunity; the concept of ‘immunity passports’ is contentious. 3 4 Concerns have indeed been raised regarding the clinical indication and resource utilization 5
There is a concern that governments could abandon antibody testing. However, given the resources already mobilized, it is not unreasonable to ask how the antibody testing program can provide more purpose, and be made more consequential. Blood sampling for anti-SARS-CoV-2 antibody requires venepuncture; the anti-SARS-CoV-2 assays utilize the same ‘high throughput automated’ platforms in wide use to test HBsAg, anti-HCV and anti-HIV. By incorporating testing for these bloods borne virus (BBV) infections, Covid-19 antibody programs could be engaged at scale to adress a problem that is widely visible, yet is not being confronted. 6 World Hepatitis Day has come and gone. Many countries are not on track to meet WHO elimination targets for viral hepatitis, because of a collective failure of screening and diagnosis. According to the WHO, 325 million people, (4% of the world's population), live with viral hepatitis, and the disease causes 1.34 million deaths per year (2015), despite effective low cost generic antiviral treatments. About 2.6 million living with HIV are also infected with HBV. Deaths from viral hepatitis are increasing, and age-related deaths among infected adults will continue to increase if they are not diagnosed and treated.7 Twenty million deaths from hepatitis B could occur between 2015 and 2030.8 Global commissions have pointed to the burden of hepatitis and liver disease in Europe, Asia, Africa and the America’s. 9
Cross over of test populations
The burden of Covid-19 disease has been unequally distributed in ethnic minority communities, who make up a high proportion of the multilayered NHS and care workforce citizenry in the United Kingdom and elsewhere. In New York City over 60% of COVID-19 deaths have been in the Black and Latino population. In Singapore, second waves of COVID-19 among migrant workers has exposed socio-economic inequalities. Infection rates and death rates have been higher in disadvantaged communities in many countries whose work force in health care, transport and the food processing industries is built on immigrants and more deprived groups. These are the same communities in whom there is a pressing need to identify silent BBV infections, which are treatable and potentially eliminable. Disease identification coupled with effective treatment renders HIV infection untransmissible (U = U), cures HCV and prevents progression of chronic hepatitis B. We could also dare to envisage serum aminotransferase determinations to ascertain nonalcoholic hepatic steatosis, and alcoholic liver disease. 10 11
The acceptance and awareness of basic social measures to contain covid-19 in the UK has been remarkable. The current societal awareness of severe viral infection leverages an opportunity to amplify awareness of viral hepatitis to the same level as that of HIV and Covid-19 (and in Sub-Saharan Africa, Ebola) to improve health. It may take a pandemic to catalyze awareness and increase testing for hepatitis B and C.
Linkage to care is critical. Communicable disease surveillance needs to contain some patient identifiers to trigger follow up. Seamlessly connected analytics, at local level will be required. For hepatitis B and C, there is demonstrable willingness for local referrals to meet national elimination targets. In England, the Second-Generation Surveillance System (SGSS) stores and manages data and is the preferred method for capturing laboratory results.
Costs, concerns, and improved objectives
Privacy and ethical concerns have already been raised for anti-SARS-CoV-2 antibody testing.3 Test positive results could cause potential harms to racial, sexual, religious or other minority groups. Thus, there is a critical need to emphasize testing for improved lifetime outcomes that will not discriminate or infringe civil liberties. Individuals can be empowered to weigh options to offset the current inconsistencies in public health strategy.
Cost and resource requirements are a consideration, but the investment in infrastructure has been made and the technological readiness exists. Sourcing, acquisition, biocontainment and dispatch of the sample is the most expensive element. Against this backdrop, the trio of tests is economical and scalable. Pooled testing can cut costs in low prevalence regions. There should not be a concern that additional testing will impact the need to contain Covid-19 infection. These programs are structured differently: Serological testing proceeds at a separate analytical rate than the propulsive pace required for Covid-19 containment by nucleic acid testing and tracing, and can connect risk groups to the flow of public health surveillance without impeding urgent tracing.
The implementation of a wider testing approach will be dependent on effective communication and public trust. Political interests and caution modulate public health policy, but country-wide collaboration with diagnostic companies can provide the intent and example unleashing, albeit indirectly, a higher yield from Covid-19 antibody testing strategies. Global public health measures require creative changes to avoid lost opportunities. Adding a trio of BBV tests to Covid-19 antibody screening would expedite a necessary but currently inadequate global communicable disease intervention by simultaneously identifying three additional and important but often silent chronic viral infections. We should urgently consider adding breadth and value to incomplete SARS-CoV-2 containment and research plans. The inscription in the slave memorial garden on the Isle de Mozambique admonishes us that “we observe the past and the future looks at us.”
GEOFFREY DUSHEIKO 1,3
GRAHAM FOSTER 2
KOSH AGARWAL 3
1 UNIVERSITY COLLEGE LONDON MEDICAL SCHOOL
2 QUEEN MARY UNIVERSITY OF LONDON
3 KINGS COLLEGE HOSPITAL
1. Angulo FJ, Finelli L, Swerdlow DL. Reopening Society and the Need for Real-Time Assessment of COVID-19 at the Community Level. JAMA 2020 doi: 10.1001/jama.2020.7872 [published Online First: 2020/05/16]
2. Del Rio C, Malani P. Translating Science on COVID-19 to Improve Clinical Care and Support the Public Health Response. JAMA 2020 doi: 10.1001/jama.2020.9252 [published Online First: 2020/05/23]
3. Kofler N, Baylis F. Ten reasons why immunity passports are a bad idea. Nature 2020;581(7809):379-81. doi: 10.1038/d41586-020-01451-0 [published Online First: 2020/05/23]
4. Phelan AL. COVID-19 immunity passports and vaccination certificates: scientific, equitable, and legal challenges. Lancet 2020;395(10237):1595-98. doi: 10.1016/S0140-6736(20)31034-5 [published Online First: 2020/05/08]
5. Anderson M, Low N, French N, et al. Rapid roll out of SARS-CoV-2 antibody testing- a concern. British Medical Journal 2020;369 doi: BMJ 2020;369:m2420 http://dx.doi.org/10.1136/bmj.m2420
6. Cooke GS, Andrieux-Meyer I, Applegate TL, et al. Accelerating the elimination of viral hepatitis: a Lancet Gastroenterology & Hepatology Commission. The Lancet Gastroenterology & Hepatology 2019;4(2):135-84. doi: 10.1016/s2468-1253(18)30270-x
7. Collaborators. PO. Global prevalence, treatment, and prevention of hepatitis B virus infection in 2016: a modelling study. The lancet Gastroenterology & hepatology 2018;3(6):383-403. doi: 10.1016/s2468-1253(18)30056-6 [published Online First: 2018/03/31]
8. WHO. Global health sector strategy on viral hepatitis 2016-2021 2016 [Available from: http://www.who.int/hepatitis/strategy2016-2021/ghss-hep/en/.
9. Sarin SK, Kumar M, Eslam M, et al. Liver diseases in the Asia-Pacific region: a Lancet Gastroenterology & Hepatology Commission. The lancet Gastroenterology & hepatology 2020;5(2):167-228. doi: 10.1016/S2468-1253(19)30342-5 [published Online First: 2019/12/20]
10. Williams R, Alexander G, Aspinall R, et al. Gathering momentum for the way ahead: fifth report of the Lancet Standing Commission on Liver Disease in the UK. The Lancet 2018;392(10162):2398-412. doi: 10.1016/s0140-6736(18)32561-3
11. Williams R, Alexander G, Armstrong I, et al. Disease burden and costs from excess alcohol consumption, obesity, and viral hepatitis: fourth report of the Lancet Standing Commission on Liver Disease in the UK. The Lancet 2018;391(10125):1097-107. doi: 10.1016/s0140-6736(17)32866-0
Competing interests: No competing interests
The original excellent and cogent letter-article has now spawned a variable (in both coherance and relevance) correspondence.
There is a case for wider population SARS-CoV-2 antibody screening and indeed PHE have such a programme which reports regularly.
It would be reckless and irresponsible to mandate urgent testing of SARS-CoV-2 Ab status. The presence or absence of Ab means little, and may vary from test to test, person to person, and over time. The idea mooted above that somehow a positive result might bring joy or fulfillment is worrying - obviously what of the fear and anguish arising from a negative test?
Tests and testing - screening or in response to trigger factors - are not toys or playthings. Ab responses except in those badly infected with SARS-CoV-2 are inconsistent and potentially dangerously misleading. A statement above from an academic running a business providing such testing to healthcare professionals is very concerning in asserting that the possession of Ab establishes immunity to re-infection. There is no such evidence.
Curiosity about Ab status is legitimate and can be answered by private companies outwith the NHS. The NHS should not be involved in this, wasting time effort and money in the process. The response to SARS-CoV-2 in the UK has been characterised by poor performance generally; rightly many bodies like PHE are under intense scrutiny now and with luck may yet be abolished (an unexpected bonus). Adding Ab testing to a litany of mis-judged and mis-timed interventions will throw yet more fuel on the reputational conflagration already engulfing many centralised sclerotic organisations involved in this pandemic response
Competing interests: No competing interests
This letter by Andersson and colleagues makes various timely points, chiefly on the importance of complying with the long-established foundation of diagnostic testing: ‘to deliver the right result of the right test to the right person at the right time’. The author echoes this statement but argues that now is indeed the right time. The only way of knowing how many people have transmitted the virus is through antibody testing. This form of testing will provide an important route to identifying the transmission and clinical characteristics of asymptomatic patients (1).
It is pertinent to consider the potential epidemiological benefits if it were possible to more precisely understand the number of those infected with SARS-CoV-2 who do not develop symptoms at all. Increased testing, brings with it an increased operational workload, as prudently stated by the authors, but it also provides an improved statistical accuracy, allowing better profiling of asymptomatic patients, leading to a better understanding, manipulation and modelling of these figures (2).
During the pandemic, there has been rapid implementation of a number of online initiatives and mobile technologies aimed at reducing the spread and aiding in the profiling of the virus pathogenesis and presentation (3). Perhaps antibody testing provides an opportunity to streamline data-gathering in patients who have contracted the virus and the symptoms they experienced. With the appropriate measures to enforce detailed symptom questionnaires this could prove fundamental in improving our understanding of the pathogenesis and presentation of this novel disease, perhaps highlighting characteristic symptoms. This can be evidenced by the addition of ageusia and anosmia to the list of recognised reasons to self-isolate updated just last month (4).
Uncovering patterns of viral transmission could in fact provide great clinical benefit to healthcare organisations. Black Asian and minority ethnic (BAME) groups (5) and male sex (6) are worse affected by SARS-CoV-2. This is multifactorial and it is poorly understood at present why this disparity exists. Job role could be a key factor in viral transmission, it could prove worthwhile to compare BAME/sex virus cases with other ethnicities/sexes within the same disciplines, to understand which roles are worst affected. This could advise further which colleagues need better protection and uncover any missed gaps. This is something that the antibody test may be able to reveal and could prove vital in optimising workflow and PPE distribution within trusts.
As summarised by the authors, ‘there must be a carefully developed and clearly articulated strategy for serological testing, with clear scientific or clinical aims (or both) as part of a unified covid-19 response strategy’. I argue there is justification for the rapid rollout of antibody testing and have highlighted how this new data could be best utilised to aid the government’s response to the covid-19 pandemic.
1. Tan, J. et al. (2020) ‘Transmission and clinical characteristics of asymptomatic patients with SARS-CoV-2 infection’, Future Virology. Future Medicine Ltd. doi: 10.2217/fvl-2020-0087.
2. Anastassopoulou, C. et al. (2020) ‘Data-based analysis, modelling and forecasting of the COVID-19 outbreak’, PLoS ONE. Public Library of Science, 15(3). doi: 10.1371/journal.pone.0230405.
3. Drew, D. A. et al. (2020) ‘Rapid implementation of mobile technology for real-time epidemiology of COVID-19’, Science. American Association for the Advancement of Science (AAAS), p. eabc0473. doi: 10.1126/science.abc0473.
5. Office for National Statistics (7 May 2020). Coronavirus (COVID-19) related deaths by ethnic group, England and Wales: 2 March 2020 to 10 April 2020. Available from: https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarri... srelateddeathsbyethnicgroupenglandandwales/2march2020to10april2020
6. Tan, J. et al. (2020) ‘Transmission and clinical characteristics of asymptomatic patients with SARS-CoV-2 infection’, Future Virology. Future Medicine Ltd. doi: 10.2217/fvl-2020-0087.
Competing interests: No competing interests
In line with expressed misgivings, and, picking out, at random, a source of antibody test kits, it is concerning to note in the manufacturer’s, ‘Limitations’ information, that the tests, have, “not been FDA cleared or approved…. Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic should be considered to rule out infection in these individuals….. Results from antibody testing should not be used as the sole basis to diagnose or exclude SARS-CoV-2 infection or to inform infection status …. Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43” (1).
It must therefore be asked, in view of the potential for cross-reactivity, why is the traditional use of ‘paired serology’ seemingly not being utilised in these cases? (2). And what consideration has been given to the phenomenon of, ‘Antibody Dependent Enhancement’? (3)
The RT-PCR test also appears to have its problems. Its inventor, Kary Mullis, who received the Nobel Prize for inventing the PCR manufacturing technique, is reported to have said that it was for research purposes only and not for medical diagnosis. An 80% false positive rate was reported from China in March 2020 (4).
A manufacturer of the, ‘SARS-CoV-2 RNA, Qualitative Real-Time RT-PCR (Test Code 39433)’ states in the package insert, “The agent detected may not be the definite cause of disease”. ‘Limitations’ include: “Negative results do not preclude SARS-CoV-2 infection and should not be used as the sole basis for treatment or other patient management decisions”.(5)
Indeed, a Swiss Institute of Microbiology reported that, antigen testing “methods based on real-time RT-PCR were recognised as reference protocols since mid-January, at the onset of the pandemic in China, and relayed – although not validated – by the World Health Organization”. They also found, ‘an incorrect degenerate base (S), that does not match with the SARS-CoV-2 RNA sequence’, and stated that other improvements to the RT-PCR test should be made in order to improve specificity.(6)
It is concerning that, at least in some cases, and maybe in all cases, neither antibody nor RT-PCR tests appear to be clinically validated nor sufficiently robust indicators on which to base recommendations for medical management or potentially major changes to individuals’ lives.
Competing interests: No competing interests
Covid 19 SARS being a new disease, has put forth challenges for understanding the intricacies of the immune response in an equation with clinical management. Antibody testing though with limitations can help bridge some gaps.
It possibly recognizes a large pool of people with positive antibodies, who can be potential donors for convalescent plasma-contributing to ongoing trials . This may be handful in the clinical management of patients in the event of secondary wave.
Subset analysis of antibody testing can also be useful for studying the immune response in the group of people who have earlier been shown to have higher risk of death including BAME .
Serial testing can also evaluate the duration of antibody response, and the protection conferred in event of resurgence of the disease. The antibodies detected today may be of value in studying antibody cross reactivity if there are newer strains of Covid virus.
Competing interests: No competing interests
Andersson and colleagues (and others before them) are questioning the value of antibody testing for SARS CoV2 infection. Indeed there are many unanswered questions – an intrinsic problem with a new disease. Thanks to awful news results reporting by at least one major diagnostic company (as Professor Deeks pointed out on Tim Harford’s More or Less programme ) , these tests have acquired a poor reputation, much of it undeserved, particularly on specificity.
Many individual patients do want to know if they have had Covid-19 or not. If only IgG results from symptomatic SARS CoV2 PCR positive patients obtained at least 2 weeks after infection are taken into account, the sensitivity of the best fingerprick and some of the ELISA methods is 95-97% and specific ~99% [2,3,4]. While not perfect, this is a high level of performance and much higher than many of the routine tests we currently do and substantially better sensitivity that SARS CoV2 PCR ~70%.
There are now some data indicating that asymptomatic SARS CoV2 infection usually generates an IgG antibody response , but sensitivity is lower. Also antibody levels fall over time, and so repeat testing many be indicated. We are missing data from children many immunocompromised groups and those of different ethnic backgrounds. Without prospective studies these data are unlikely to be generated in the UK, because of the necessary linkage with medical records required for analysis, which requires explicit consent and is unattainable for a devolved laboratory system as the PHE is currently structured without substantial resource put into gaining consent. The UK’s tight rules on consent for this sort of linkage data is an impediment to data generation for public health benefit, as in the current crisis.
One definitive benefit of knowing that a person is SARS CoV2 IgG positive is that these antibodies take 2-4 weeks to develop [3,6]. While SARS CoV2 PCR tests are positive for up to 7 weeks in non-immunocompromised patients , viable virus is not detectable after about 8 days [8,9], unless immunocompromised. So this gives real assurance that patients are non-infectious with a 99% degree of certainly (1% false positive rate). A positive IgG test could therefore be used for safely discharging patients from isolation and to other care facilities.
Andersson et al also question whether antibody reflects immunity . Most patients with SARS CoV2 IgG have neutralising antibody [5,10,11] as well as IgA and cytotoxic T cells directed against the SARS CoV2 virus [12,13] and so immunity against re-infection is highly likely, while the IgG remains positive. These data have now been generated in both symptomatic Covid-19 and asymptomatic patients . The duration of these broad immune responses clearly needs longitudinal study , and is highly relevant to the proxy markers for immunity generated by vaccines.
The false positive IgG rate of the best SARS CoV2 IgG antibody tests is ~1%, so 1 in 100 will be falsely classified as having had SARS CoV2 infection when they have not. Limited but provocative data suggests may have cross-reactivity from another coronavirus and have some protection .
I need to declare an interest – I am one of the co-founders of www.DenScreen.co.uk a company completely financed by its founders to assist in getting dentists back to work safely. Dental professionals are probably at high risk of acquiring (and possibly transmitting) SARS CoV2. Enhanced PPE is currently advised for all aerosol generating procedures, which has substantial cost and practical implications. DenScreen offers a full education package, advanced triage and a top performing fingerprick SARS CoV2 antibody test to be done in previously symptomatic patients at least 3 weeks after infection. Our position, based on the published science quoted here, is that a positive IgG antibody test means patients are non-infectious and can have standard universal precautions instead of enhanced PPE. DenScreen’s plan is to collect all the data antibody data and basic demography to better understand the background infection rates in dental workers and in patients. About 20 million people visit the dentist every year, so major population analyses are possible, if there is good update of antibody testing.
David W. Denning
Professor of Infectious Diseases in Global Health
The University of Manchester.
1. Harford T. More or Less https://www.bbc.co.uk/sounds/play/m000jw02 June 10th 2020
2. Mahase E. Covid-19: Two antibody tests are “highly specific” butvary in sensitivity, evaluations find. MJ 2020;369:m2066 doi: 10.1136/bmj.m2066
3. Van Elslande J, Houben E, Depypere M, et al. Diagnostic Performance of Seven Rapid IgG/IgM Antibody Tests and the Euroimmun IgA/IgG ELISA in COVID-19 Patients. Clin Microbiol Infect 2020 May 28;S1198-743X(20)30300-1. doi: 10.1016/j.cmi.2020.05.023.
4. Lassaunière R, Frische A, Harboe ZB, et al. Evaluation of nine commercial SARS-CoV-2 immunoassays https://www.medrxiv.org/content/10.1101/2020.04.09.20056325v1
5. Long, Q., Tang, X., Shi, Q. et al. Clinical and immunological assessment of asymptomatic SARS-CoV-2 infections. Nat Med 2020 https://doi.org/10.1038/s41591-020-0965-6
6. Qu J, Wu C, Li X, et al. Profile of IgG and IgM Antibodies Against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Clin Infect Dis 2020 Apr 27;ciaa489. doi: 10.1093/cid/ciaa489.
7. Carmo A, Pereira-Vaz J, Mota V, et al. Clearance and Persistence of SARS-CoV-2 RNA in Patients With COVID-19. J Med Virol 2020 Jun 2;10.1002/jmv.26103. doi: 10.1002/jmv.26103.
8. Wölfel R, Corman VM, Guggemos W, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020;581(7809):465-469. doi:10.1038/s41586-020-2196-x
9. Bullard J, Dust K, Funk D, et al. Predicting infectious SARS-CoV-2 from diagnostic samples [published online ahead of print, 2020 May 22]. Clin Infect Dis. 2020;ciaa638. doi:10.1093/cid/ciaa638
10. Kohmer N, Westhaus S, Rühl C, Ciesek S, Rabenau HF. Clinical Performance of Different SARS-CoV-2 IgG Antibody Tests. J Med Virol 2020 Jun 8;10.1002/jmv.26145. doi: 10.1002/jmv.26145.
11. Danh K, Karp DG, Robinson PV, et al. Detection of SARS-CoV-2 neutralizing antibodies with a cell-free PCR assay. medRxiv 2020 Jun 2;2020.05.28.20105692. doi: 10.1101/2020.05.28.20105692.
12. Grifoni A, Weiskopf D, Ramirez SI, et al. Targets of T Cell Responses to SARS-CoV-2 Coronavirus in Humans With COVID-19 Disease and Unexposed Individuals Cell 2020 May 20;S0092-8674(20)30610-3. doi: 10.1016/j.cell.2020.05.015.
13. Peng Y, Mentzer AJ, Liu G, et al. Broad and Strong Memory CD4 + and CD8 + T Cells Induced by SARS-CoV-2 in UK Convalescent COVID-19 Patients. bioRxiv. 2020 Jun 8:2020.06.05.134551. doi: 10.1101/2020.06.05.134551.
14. Du Z, Zhu F, Guo F, Yang B, Wang T. Detection of Antibodies Against SARS-CoV-2 in Patients With COVID-19. J Med Virol 2020 Apr 3;10.1002/jmv.25820. doi: 10.1002/jmv.25820.
Competing interests: Co-founder and shareholder in DenScreen
We have published a paper with 12 tables (in a supplementary file) with calculations of sensitivity, specificity and the predictive power of a positive and negative test that will help people understand the concerns about the rapid roll-out of SARS-CoV-2 antibody tests expressed by Andersson and colleagues. With our colleagues  we showed that even at high levels of specificity, an important proportion of positive test results will be false positives, when the prevalence of the infection in the population is low.
Currently, surveys suggest around 5% of the UK population have had covid-19. At this prevalence, when using an antibody test system with 99% specificity and 99% sensitivity (which are difficult to achieve in clinical practice even if achieved in research circumstances) 16.2 % of positive test results would be in people who have not had the disease (predictive power of a positive test 83.8%). Put another way, if 100,000 people were to be tested, 5900 people would test positive, but of these 950 would be false positives.
Unfortunately, without additional clinical information, one couldn’t be sure who genuinely had had the infection and who had not. These are matters of probabilities not certainties. We conclude our article by saying: “Giving false reassurance on which personal or societal decisions might be based could be harmful for individuals, undermine public confidence and foster further outbreaks.”
It is imperative that antibody tests are used thoughtfully and combined with other relevant information that increases the prior probability of the disease being present e.g. a previous typical clinical history or even better, virological evidence of infection. Our paper also provides calculations for prevalences of 10% and 20%, figures that may apply in the future in whole populations, and probably apply now in some settings e.g. hospitals or care homes.
1 Kumleben N, Bhopal R, Czypionka T, Gruer L, Kock R, Stebbing J, Stigler FL. Test, test, test for COVID-19 antibodies: the importance of sensitivity, specificity and predictive powers.
Public Health 2020;185:88-90. https://doi.org/10.1016/j.puhe.2020.06.006
Competing interests: No competing interests
Given that it is agreed that surviving a previous COVID infection is likely to signify some degree of protection, even if we don't know how much or for how long, a positive antibody test result may nevertheless have some benefit for individuals. At the very least it may provide some degree of reassurance and hope, albeit with caveats, with a positive impact on mental health. It is unreasonable to ignore such a positive impact and define it as being 'of no clinical benefit' to the individual.
Competing interests: No competing interests
I know nothing about the SARS-COV-2 antibodies. Nor about the tests. Nor about the duration of persistence of the antibodies in a quantity that MIGHT protect the person from further infection (which might be sub-clinical, or clinical, or might simply and unfortunately, result in some obscure immunological reaction - with unknown , unforeseen damages to the body).
The foregoing also leads me on to the question:
Since the antibody tests are completely useless in telling one whether one is immune, partially immune or non-immune, how does a person who is injected with one of the vaccines (being currently developed in our own OXFORD) know whether he is immune, partially or completely, to infection with the wild virus? And is there a possibility that he will, when he inhales the wild virus, he will not suffer the obscure immunological reactions mentioned in the preceding paragraph?
There are other questions. But if a scientist, medical or non-medical, not employed or contracted as a public relations officer by our world class universities, can answer these questions, I will be grateful.
Competing interests: No competing interests