The Protective Effect of SARS-CoV-2 Antibodies in Scottish Healthcare Workers

Abstract

Background: Healthcare workers (HCWs) are believed to be at increased risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. It is not known to what extent the natural production of antibodies to SARS-CoV-2 is protective against re-infection. Methods: A prospective observational study of HCWs in Scotland (UK) from May to September 2020 was performed. The Siemens SARS-CoV-2 total antibody assay was used to establish seroprevalence in this cohort. Controls, matched for age and sex to the general local population, were studied for comparison. New infections (up to 2 December 2020) post antibody testing were recorded to determine whether the presence of SARS-CoV-2 antibodies protects against re-infection. Results: A total of 2063 health and social care workers were recruited for this study. At enrolment, 300 HCWs had a positive antibody test (14.5%). 11 out of 231 control sera tested positive (4.8%). HCWs therefore had an increased likelihood of a positive test (OR 3.4, 95% CI 1.85-6.16; p<0.0001). Dentists were most likely to test positive. 97.3% of patients who had previously tested positive for SARS-CoV-2 by reverse transcriptase (RT)-PCR had positive antibodies. 18.7% had an asymptomatic infection. There were 38 new infections with SARS-CoV-2 in HCWs who were previously antibody negative, and one symptomatic RT-PCR-positive re-infection. The presence of antibodies was therefore associated with an 85% reduced risk of re-infection with SARS-CoV-2 (hazard ratio 0.15, 95% CI 0.06-0.35; p=0.026). Conclusion: HCWs were three times more likely to test positive for SARS-CoV-2 than the general population. Almost all infected individuals developed an antibody response, which was 85% effective in protecting against re-infection with SARS-CoV-2. @ERSpublicationsIn this study, healthcare workers were three times more likely to test positive for #SARSCoV2 than the general population. Almost all infected individuals developed an antibody response, and this was 85% effective in protecting against re-infection.

Risk of reinfection and disease after SARS‐CoV‐2 primary infection: Meta‐analysis

“…Of the 3282 papers initially retrieved, we included 91 cohort studies evaluating the onset of reinfection, severe and very severe/lethal COVID‐19 among 15,034,624 previously infected subjects (Figure 1), either among health care workers (27 publications; n = 37,598 2,8,9,15,17,24,36,38,42–59 ) or in the general population (67 publications; n = 14,997,026 3–7,10,12,16–23,25–27,43,49,60–106 ).…”

“…As shown in Table S1, most of the included studies ( n = 43) were carried out in Europe, 2,4–10,12,15,17,18,21,24,26,36,38,44,46–51,58,66,69,71,72,75,81,85–88,91–93,95,99,102 24 in the USA, 20,22,23,25,42,43,57,59,63,67,77,79,82–84,89,90,97,98,103,105–107 18 in Asia 3,16,19,27,45,52–54,56,60,62,64,65,70,73,74,100,101 and the remaining six in South America or South Africa 61,68,80,94,96,104 . The mean age of the participants ranged from 15 to 87 years, and the average follow‐up ranged from 29 to 371 days.…”

Highly Effective Naturally Acquired Protection Against COVID-19 Persists for at Least 1 Year: A Meta-Analysis

“…The mean or median age of the study populations ranged from 19 to 59 years. Among the 10,123,319 subjects enrolled in the studies (42.8% of males), 67,124 were polymerase chain reaction (PCR)epositive (4), seropositive (7), or PCR/seropositive (4) with documented reinfection in 0.6% of cases beyond 60-120 days after complete resolution of the first infection. The mean follow-up time for reinfection was 234 days (range, 180-360 days) between March 2020 and May 2021.…”

Immune response against SARS-CoV-2 of primary healthcare personnel in a commune of Santiago, Chile: follow-up at 6 months

“…The prevalence found (22.3%) is very similar to that reported in a study conducted in healthcare workers at a hospital in Santiago from April to July 2020 (24%) (19) and consistent with previous evidence in health personnel, whose seroprevalence is higher than what is observed in the community, demonstrating the high risk faced by these personnel. (33)(34)(35)(36)(37)(38) When controlling for potential confounding variables in our study, the medical profession increases the chance of disease. This finding is probably associated with the greater time that these professionals spend in PHC providing care to people with recent onset of the disease, when there is a greater risk of transmission.…”