Seroprevalence of SARS-CoV-2 Antibodies and Factors Associated with Seropositivity at the University of Salamanca: The DIANCUSAL Study

Abstract

Background: Systematic screening for antibodies against SARS-CoV-2 is a crucial tool for surveillance of the COVID-19 pandemic. The University of Salamanca (USAL) in Spain designed a project called “DIANCUSAL” (Diagnosis of New Coronavirus, COVID-19, in University of Salamanca) to measure antibodies against SARS-CoV-2 among its ~34,000 students and academic staff, as the influence of the university community in the spread of the SARS-CoV-2 pandemic in the city of Salamanca and neighboring towns hosting USAL campuses could be substantial. Objective: The aim of this study was to estimate the prevalence of SARS-CoV-2 antibodies among USAL students, professors and staff and to evaluate the demographic, academic, clinical and lifestyle and behavioral factors related to seropositivity. Methodology: The DIANCUSAL study is an ongoing university population-based cross-sectional study, with the work described herein conducted from July–October 2020. All USAL students, professors and staff were invited to complete an anonymized questionnaire. Seroprevalence of anti-SARS-CoV-2 antibodies was detected and quantified by using chemiluminescent assays for IgG and IgM. Principal findings: A total of 8197 (24.71%) participants were included. The mean age was 31.4 (14.5 SD) years, and 66.0% of the participants were female. The seroprevalence was 8.25% overall and was highest for students from the education campus (12.5%) and professors from the biomedical campus (12.6%), with significant differences among faculties (p = 0.006). Based on the questionnaire, loss of smell and fever were the symptoms most strongly associated with seropositivity, and 22.6% of seropositive participants were asymptomatic. Social distancing was the most effective hygiene measure (p = 0.0007). There were significant differences in seroprevalence between participants with and without household exposure to SARS-CoV-2 (p = 0.0000), but not between students who lived in private homes and those who lived in dormitories. IgG antibodies decreased over time in the participants with confirmed self-reported COVID-19 diagnoses. Conclusions: The analysis revealed an overall 8.25% seroprevalence at the end of October 2020, with a higher seroprevalence in students than in staff. Thus, there is no need for tailored measures for the USAL community as the official average seroprevalence in the area was similar (7.8% at 22 June and 12.4 at 15 November of 2020). Instead, USAL members should comply with public health measures.

Predictors of SARS-CoV-2 Infection in University Students: A Case-Control Study

“…Notably, there were no significant differences between students of healthcare and other faculties, although the former was slightly more often positive. These results contrast to some extent with the findings that healthcare students seem to have a high prevalence of previous SARS-CoV-2 contacts [ 14 ]. Indeed, while healthcare workers have a high prevalence of previous infections with SARS-CoV-2 [ 38 ] and a high risk of infection [ 39 , 40 ], undergraduate students probably have reduced contact with patients and access to hospital wards because of the general restrictions in access to healthcare services, thus reducing their risk of infection.…”

“…Interestingly, students in the second year or above appeared to be more likely to contract a SARS-CoV-2 infection. Indeed, Moro et al reported a higher prevalence of anti-SARS-CoV-2 antibodies in postgraduate students than in undergraduates [ 14 ]. These findings may be due to the possibly wider social network of students in the higher years, together with a propensity of early-year students to adhere more closely to institution rules [ 37 ].…”

“…Nevertheless, evidence of HEIs as enhancers of SARS-CoV-2 spread is sparse and mixed. Studies on the prevalence of SARS-CoV-2 antibodies in various university communities suggest that the circulation of the virus in these communities, before the closure of teaching activities, was essentially identical to that of the general population [ 12 , 13 , 14 ]. However, there have been reports of outbreaks on campuses after HEIs reopened [ 15 , 16 , 17 , 18 ], thus highlighting a possible role of these institutions in sustaining the pandemic.…”

SARS-CoV-2 Exposition und Seroprävalenz von SARS-CoV-2-Antikörpern bei Medizinstudierenden in der ersten Phase der Pandemie, 2020–2021

“…Zum SARSCoV2Serostatus von Medizinstudierenden gibt es auch international bislang nur wenige veröffentlichte Daten [6,7]. Mit einem standardisierten OnlineFragebogen (Programm Eva Sys V8.0, 2022; Electronic Paper Evaluationssystem GmbH) wur den soziodemographische Daten der Teilnehmenden sowie mög liche Expositionen gegenüber SARSCoV2 im privaten, universitä ren und ggf.…”

“…Zum SARS-CoV-2-Serostatus von Medizinstudierenden gibt es auch international bislang nur wenige veröffentlichte Daten 6 7 . Ziel der im Jahr 2020 begonnenen Studie war, die Seroprävalenz von Medizinstudierenden in der Anfangsphase der Pandemie zu ermitteln und mögliche Risikofaktoren für SARS-CoV-2-Exposition zu erfassen, um gegebenenfalls zeitnah Konsequenzen hinsichtlich ihrer Schulung zur Umsetzung von Infektionsschutz- und Hygienemaßnahmen ziehen zu können und damit zu einem besseren Schutz der Medizinstudierenden selbst und der von ihnen mitbetreuten Patienten beizutragen.…”