Portal de Periódicos da CAPES

The serostatus approach to fighting COVID-19

2020; Elsevier BV; Volume: 94; Linguagem: Inglês

10.1016/j.ijid.2020.03.080

1878-3511

Chris Kenyon,

COVID-19 epidemiological studies

A serostatus approach could assist combating both the COVID-19 pandemic and some of its knock-on effects such as the economic downturn and epidemic of anxiety that have followed it. The serostatus approach would involve the rapid roll-out of serological testing of heavily affected populations. Those who test positive would be allowed to return to normal activities whilst those testing negative would be encouraged to minimize their exposure. A number of features of COVID-19 make it amenable to a serostatus approach. In keeping with serological tests for SARS-CoV-1, those for SARS-CoV-2 appear to be highly specific and sensitive – with reported specificities of up to 100% (Amanat et al., 2020Amanat F. Nguyen T. Chromikova V. et al.A serological assay to detect SARS-CoV-2 seroconversion in humans.medRxiv. 2020; Google Scholar, IBTC, 2019Innovita Biological Technology Co. 2019-nCoV Ab Test (Colloidal Gold) (IgM/IgG Whole Blood/Serum/Plasma Combo).2019Google Scholar). This high specificity means that the test could reliably confirm that an individual has been infected with SARS-CoV-2. The available evidence suggests that these individuals will be immune to reinfection for at least the short to medium term (Woelfel et al., 2020Woelfel R. Corman V.M. Guggemos W. et al.Clinical presentation and virological assessment of hospitalized cases of coronavirus disease 2019 in a travel-associated transmission cluster.medRxiv. 2020; Google Scholar). Although sample sizes were small, detailed serological studies in infected persons indicate that all infected persons develop high levels of neutralizing antibodies from around the 14th day after symptom onset (Woelfel et al., 2020Woelfel R. Corman V.M. Guggemos W. et al.Clinical presentation and virological assessment of hospitalized cases of coronavirus disease 2019 in a travel-associated transmission cluster.medRxiv. 2020; Google Scholar, Lee et al., 2020Lee N.-Y. Li C.-W. Tsai H.-P. et al.A case of COVID-19 and pneumonia returning from Macau in Taiwan: clinical course and anti-SARS-CoV-2 IgG dynamic.J Microbiol Immunol Infect. 2020; Crossref Scopus (41) Google Scholar). The level of antibodies produced did not vary between those with minimal and severe symptoms (Woelfel et al., 2020Woelfel R. Corman V.M. Guggemos W. et al.Clinical presentation and virological assessment of hospitalized cases of coronavirus disease 2019 in a travel-associated transmission cluster.medRxiv. 2020; Google Scholar). Around 80% of those infected and who develop symptoms only experience mild symptoms (Wu and McGoogan, 2020Wu Z. McGoogan J.M. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention.JAMA. 2020; Crossref Scopus (12134) Google Scholar). At least 30% of infected persons will not develop any symptoms at all (Nishiura et al., 2020Nishiura H. Kobayashi T. Miyama T. et al.Estimation of the asymptomatic ratio of novel coronavirus infections (COVID-19).Int J Infect Dis. 2020; Google Scholar). These features suggest that widespread serological testing could have multiple benefits. In many countries nucleic acid amplification (NAAT) diagnostic testing was limited due to supply and other constraints. In Belgium, for example, contacts of COVID-19 patients including Health Care workers with symptoms of upper respiratory tract infections without fever were not eligible for NAAT testing (BDH, 2020Belgian Department of Health Coronavirus COVID-19.2020Google Scholar). Studies from elsewhere indicate that a considerable proportion of those exposed, such as health care workers would be infected (Wu and McGoogan, 2020Wu Z. McGoogan J.M. Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention.JAMA. 2020; Crossref Scopus (12134) Google Scholar). These could be detected via serological testing and they could be safely released from home confinement (as is the practice in many countries currently) and prioritized for return to work. This would have a number of benefits. A considerably larger number of persons would become aware of the fact that they had been infected with minimal or no symptoms, which could reduce the fear associated with COVID-19. Those testing positive would be able to return to work which would assist with economic recovery. In the health care, and related sectors such as care-of-the-elderly facilities, recovered individuals could be favored for patient contact which would reduce transmission between health care workers and patients. Finally, testing could identify a large number of immune individuals whose serum could be used for convalescent therapy (Casadevall and Pirofski, 2020Casadevall A. Pirofski L.-A. The convalescent sera option for containing COVID-19.J Clin Invest. 2020; 130Crossref Scopus (641) Google Scholar). The primary disadvantages of this strategy include the logistical arrangements of setting up the new serological assay and testing of large numbers of individuals. There is also some uncertainty as the strength and duration of immunity to recurrent infections (Woelfel et al., 2020Woelfel R. Corman V.M. Guggemos W. et al.Clinical presentation and virological assessment of hospitalized cases of coronavirus disease 2019 in a travel-associated transmission cluster.medRxiv. 2020; Google Scholar). These disadvantages would likely be offset by the positive effects on reducing transmission (including of subsequent waves of COVID-19 (Morens and Fauci, 2007Morens D.M. Fauci A.S. The 1918 influenza pandemic: insights for the 21st century.J Infect Dis. 2007; 195: 1018-1028Crossref PubMed Scopus (395) Google Scholar)), the economy and mental health. Not applicable. Not applicable. No specific funding was received for this work.