Objectives To assess the seroprevalence of anti-SARS-CoV-2 IgG among health careworkers (HCWs) in our university hospital and verify the risk of acquiring the infection according to work area. Design Cross-sectional study. Setting Monocentric, Italian, third-level university hospital. Participants All the employees of the hospital on a voluntary base, for a total of 4055 participants among 4572 HCWs (88.7%). Primary and secondary outcome measures Number of anti-SARS-CoV-2 positive serology according to working area. Association of anti-SARS-CoV-2 positive serology to selected variables (age, gender, country of origin, body mass index, smoking, symptoms and contact with confirmed cases). Results From 27 April 2020 to 12 June 2020, 4055 HCWs were tested and 309 (7.6%) had a serological positive test. No relevant difference was found between men and women (8.3% vs 7.3%, p=0.3), whereas a higher prevalence was observed among foreign-born workers (27/186, 14.5%, p<0.001), employees younger than 30 (64/668, 9.6%, p=0.02) or older than 60 years (38/383, 9.9%, p=0.02) and among healthcare assistants (40/320, 12.5%, p=0.06). Working as frontline HCWs was not associated with an increased frequency of positive serology (p=0.42). A positive association was found with presence and number of symptoms (p<0.001). The symptoms most frequently associated with a positive serology were taste and smell alterations (OR 4.62, 95% CI: 2.99 to 7.15) and fever (OR 4.37, 95% CI: 3.11 to 6.13). No symptoms were reported in 84/309 (27.2%) HCWs with positive IgG levels. Declared exposure to a suspected/confirmed case was more frequently associated (p<0.001) with positive serology when the contact was a family member (19/94, 20.2%) than a patient or colleague (78/888, 8.8%). Conclusions SARS-CoV-2 infection occurred undetected in a large fraction of HCWs and it was not associated with working in COVID-19 frontline areas. Beyond the hospital setting, exposure within the community represents an additional source of infection for HCWs.

Seroprevalence of anti-SARS-CoV-2 IgG among healthcare workers of a large university hospital in Milan, Lombardy, Italy: A cross-sectional study / A. Lombardi, D. Mangioni, D. Consonni, L. Cariani, P. Bono, A.P. Cantu, B. Tiso, M. Carugno, A. Muscatello, G. Lunghi, A.C. Pesatori, L. Riboldi, F. Ceriotti, A. Bandera, A. Gori. - In: BMJ OPEN. - ISSN 2044-6055. - 11:2(2021), pp. e047216.1-e047216.9.

Seroprevalence of anti-SARS-CoV-2 IgG among healthcare workers of a large university hospital in Milan, Lombardy, Italy: A cross-sectional study

A. Lombardi
Co-primo
;
D. Mangioni
Co-primo
;
L. Cariani;P. Bono;M. Carugno;A.C. Pesatori;A. Bandera;A. Gori
2021

Abstract

Objectives To assess the seroprevalence of anti-SARS-CoV-2 IgG among health careworkers (HCWs) in our university hospital and verify the risk of acquiring the infection according to work area. Design Cross-sectional study. Setting Monocentric, Italian, third-level university hospital. Participants All the employees of the hospital on a voluntary base, for a total of 4055 participants among 4572 HCWs (88.7%). Primary and secondary outcome measures Number of anti-SARS-CoV-2 positive serology according to working area. Association of anti-SARS-CoV-2 positive serology to selected variables (age, gender, country of origin, body mass index, smoking, symptoms and contact with confirmed cases). Results From 27 April 2020 to 12 June 2020, 4055 HCWs were tested and 309 (7.6%) had a serological positive test. No relevant difference was found between men and women (8.3% vs 7.3%, p=0.3), whereas a higher prevalence was observed among foreign-born workers (27/186, 14.5%, p<0.001), employees younger than 30 (64/668, 9.6%, p=0.02) or older than 60 years (38/383, 9.9%, p=0.02) and among healthcare assistants (40/320, 12.5%, p=0.06). Working as frontline HCWs was not associated with an increased frequency of positive serology (p=0.42). A positive association was found with presence and number of symptoms (p<0.001). The symptoms most frequently associated with a positive serology were taste and smell alterations (OR 4.62, 95% CI: 2.99 to 7.15) and fever (OR 4.37, 95% CI: 3.11 to 6.13). No symptoms were reported in 84/309 (27.2%) HCWs with positive IgG levels. Declared exposure to a suspected/confirmed case was more frequently associated (p<0.001) with positive serology when the contact was a family member (19/94, 20.2%) than a patient or colleague (78/888, 8.8%). Conclusions SARS-CoV-2 infection occurred undetected in a large fraction of HCWs and it was not associated with working in COVID-19 frontline areas. Beyond the hospital setting, exposure within the community represents an additional source of infection for HCWs.
occupational & industrial medicine; virology; diagnostic microbiology; public health
Settore MED/17 - Malattie Infettive
Article (author)
File in questo prodotto:
File Dimensione Formato  
e047216.full.pdf

accesso aperto

Tipologia: Publisher's version/PDF
Dimensione 362.53 kB
Formato Adobe PDF
362.53 kB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/848992
Citazioni
  • ???jsp.display-item.citation.pmc??? 13
  • Scopus 14
  • ???jsp.display-item.citation.isi??? 13
social impact