Prevalence of serum IgG antibodies against SARS-CoV-2 among clinic staff

Abstract

The SARS-CoV-2 pandemic threatens health care providers and society. For planning of treatment capacities, it is of major importance to obtain reliable information on infection and fatality rates of the novel coronavirus. A German community study, the so-called Heinsberg study, found a 5-fold higher infection rate (and thus a remarkably lower fatality rate) than the officially reported cases suggest. We were interested to examine the SARS-CoV-2-IgG antibody status among clinic staff of a large neurological center in Northern Germany. Blood samples and questionnaires (demographic data, medical history) were collected pseudonymously. In total, 406 out of 525 (77.3%) of our employees participated in the study. The infection rate among the staff was as high as 2.7%. Including drop-outs (missing questionnaire but test result available), the infection rate was even higher (2.9%). Only 36% of the positively tested employees did suffer from flu-like symptoms in 2020. None of the nurseshaving closest and longest contact to patients-were found to be positive. Despite the fact that the infection rate among clinic staff may not be directly compared to the situation in the surrounding county (due to different testing procedures), one might hypothesize that the infection rate could be more than 30-fold higher than the number of officially reported cases for the county of Hameln-Pyrmont. The high rate of IgG-positive, asymptomatic healthcare workers might help to overcome fears in daily work.

Prevalence of SARS-CoV-2 infection in previously undiagnosed health care workers in New Jersey, at the onset of the U.S. COVID-19 pandemic

“…Some studies have reported high rates of infection or antibody positivity among clinicians [24] and lower status support roles, such as janitorial staff [18], whereas other studies observe no differences in infection by job role [19,20]. One other study specifically reported on infections in nurses, noting that, in contrast to our study, none of the 155 nurses sampled tested positive for SARS-Cov-2 antibodies; however, overall antibody positivity among HCW was quite low in that study (11/406; 2.9%) [25]. Considered as a whole, the body of work on SARS-CoV-2 among HCW suggests considerable inter-hospital variation which may be attributable to differences in hospital policies and practices as well as rates of infection in the surrounding communities.…”

Neutralizing Antibody Production in Asymptomatic and Mild COVID-19 Patients, in Comparison with Pneumonic COVID-19 Patients

“…Other data reported various sero-positive rates of COVID-19 caring HCWs, from 0.83% (of 134 ICU HCWs, NJ, USA [ 17 ]) to 32.6% (of 285 HCWs, NY, USA [ 18 ]). These seroprevalences COVID-19 caring HCWs might be affected not only by ICP protocols, but also largely by local outbreak burdens, as sero-prevalences of non-COVID-19 caring HCWs were also high in regions of high outbreak burdens [ 19 , 20 ]. On the perspective of therapeutics, CP and/or hyperimmune immunoglobulin could be used, expecting an anti-viral effect of naturally produced neutralizing antibodies of recovered COVID-19 patients.…”

Antibody response to SARS-CoV-2 infection in humans: a systematic review

“…Two study reported that asymptomatic healthcare workers did develop antibodies. 161,162 • Fever appears to have a consistent relationship with seropositivity and antibody titres, 29,158,160 although other symptoms such as ageusia have also been associated. 156,158…”