Longitudinal profile of antibody response to SARS-CoV-2 in patients with COVID-19 in a setting from Sub-Saharan Africa: A prospective longitudinal study

• Published in: PloS one Vol. 17; no. 3; p. e0263627
• Main Authors: Gebrecherkos, Teklay, Kiros, Yazezew Kebede, Challa, Feyissa, Abdella, Saro, Gebreegzabher, Atsbeha, Leta, Dereje, Desta, Abraham, Hailu, Ataklti, Tasew, Geremew, Abdulkader, Mahmud, Tessema, Masresha, Tollera, Getachew, Kifle, Tsigereda, Arefaine, Zekarias Gessesse, Schallig, Henk Hdf, Adams, Emily R, Urban, Britta C, de Wit, Tobias F Rinke, Wolday, Dawit
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23.03.2022; Public Library of Science (PLoS)
• Subjects: Adult; Analysis; Antibodies; Antibodies, Viral - immunology; Antibody Formation; Antibody response; Asymptomatic; Biology and life sciences; Coronaviruses; COVID-19; COVID-19 - epidemiology; COVID-19 - immunology; COVID-19 Serological Testing - methods; Electrochemiluminescence; Epidemiology; Ethiopia - epidemiology; Female; Health sciences; Humans; Immunoassay; Immunoglobulin G; Immunoglobulin M; Infections; Laboratories; Longitudinal Studies; Male; Medical research; Medicine and Health Sciences; Middle Aged; Pandemics; Patient Acuity; Prospective Studies; Public health; Research and Analysis Methods; Sample size; SARS-CoV-2 - immunology; Seroconversion; Serodiagnosis; Seroepidemiologic Studies; Serology; Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Testing; Vaccines; Viral antibodies; Ethiopia; Sub-Saharan Africa; Netherlands; United Kingdom > UK; Africa; Addis Ababa Ethiopia
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0263627

Serological testing for SARS-CoV-2 plays an important role for epidemiological studies, in aiding the diagnosis of COVID-19, and assess vaccine responses. Little is known on dynamics of SARS-CoV-2 serology in African settings. Here, we aimed to characterize the longitudinal antibody response profile to SARS-CoV-2 in Ethiopia. In this prospective study, a total of 102 PCR-confirmed COVID-19 patients were enrolled. We obtained 802 plasma samples collected serially. SARS-CoV-2 antibodies were determined using four lateral flow immune-assays (LFIAs), and an electrochemiluminescent immunoassay. We determined longitudinal antibody response to SARS-CoV-2 as well as seroconversion dynamics. Serological positivity rate ranged between 12%-91%, depending on timing after symptom onset. There was no difference in positivity rate between severe and non-severe COVID-19 cases. The specificity ranged between 90%-97%. Agreement between different assays ranged between 84%-92%. The estimated positive predictive value (PPV) for IgM or IgG in a scenario with seroprevalence at 5% varies from 33% to 58%. Nonetheless, when the population seroprevalence increases to 25% and 50%, there is a corresponding increases in the estimated PPVs. The estimated negative-predictive value (NPV) in a low seroprevalence scenario (5%) is high (>99%). However, the estimated NPV in a high seroprevalence scenario (50%) for IgM or IgG is reduced significantly to 80% to 85%. Overall, 28/102 (27.5%) seroconverted by one or more assays tested, within a median time of 11 (IQR: 9-15) days post symptom onset. The median seroconversion time among symptomatic cases tended to be shorter when compared to asymptomatic patients [9 (IQR: 6-11) vs. 15 (IQR: 13-21) days; p = 0.002]. Overall, seroconversion reached 100% 5.5 weeks after the onset of symptoms. Notably, of the remaining 74 COVID-19 patients included in the cohort, 64 (62.8%) were positive for antibody at the time of enrollment, and 10 (9.8%) patients failed to mount a detectable antibody response by any of the assays tested during follow-up. Longitudinal assessment of antibody response in African COVID-19 patients revealed heterogeneous responses. This underscores the need for a comprehensive evaluation of seroassays before implementation. Factors associated with failure to seroconvert needs further research.