Acute SARS-CoV-2 infection and seropositivity among healthcare workers and medical students in summer 2020, Hungary.

OBJECTIVES: The aim was to compare the prevalence of acute infection and seropositivity of SARS-CoV-2 among healthcare workers (HCWs) and medical students. MATERIAL AND METHODS: A high-volume, single-center analysis was conducted in the period of July 1‒August 1, 2020, at the Semmelweis University. Naso- and oropharyngeal samples were collected for polymerase chain reaction (PCR), and blood samples for anti-SARS-CoV-2 IgG. A questionnaire was also administered about the infection symptoms and the obtained results were assessed by profession and site of care delivery. RESULTS: From the total cohort (N = 7948), 4478 (56%) and 3470 (44%) were health professionals and medical students, respectively. They were mainly female (67%), and the mean age of HCWs and students was 40 and 25 years, respectively. By profession, physicians (1.5%) and other HCWs (1.8%) showed a comparable SARS-CoV-2 exposure. International students had the highest (2.1%), whereas Hungarian students had the lowest (0.6%) prevalence of seropositivity. The highest prevalence was detected among the staff of COVID-19 wards (12.1%). By PCR, medical students showed the lowest occurrence of active infection with a prevalence of 0.17%, while physicians and other HCWs had a higher prevalence (1.46% and 1.71%, respectively). By site of care delivery, positive test results were the most frequent at COVID-19 wards (3.8%). CONCLUSIONS: Physicians and other HCWs showed comparable SARS-CoV-2 seropositivity prevalence, approximately twice as high as in the general population of Budapest. Hungarian students had lower prevalence of seropositivity than this reference. High prevalence among international students suggests that they had imported the infection. The very high prevalence of documented exposure among staff members at COVID-19 wards urges for improving the safety measures. Int J Occup Med Environ Health. 2022;35(2):209-16.

Novel coronavirus epidemic in the Hungarian population, a cross-sectional nationwide survey to support the exit policy in Hungary.

After months of restrictive containment efforts to fight the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) epidemic, European countries are planning to reopen. To support the process, we conducted a cross-sectional survey among the Hungarian population to estimate the prevalence of infectious cases and prior SARS-CoV-2 exposure. A representative sample (n = 17,787) for the Hungarian population of 14 years or older living in private households (n = 8,283,810) was selected. The study was performed within 16 days after 50 days of restrictions, when the number of confirmed cases was stable low. Naso- and oropharyngeal smears and blood samples were collected for PCR and antibody testing. The testing was accompanied by a questionnaire about symptoms, comorbidities, and contacts. Design-based prevalence estimates were calculated. In total, 10,474 individuals (67.7% taken into account a sample frame error of 2315) of the selected sample participated in the survey. Of the tested individuals, 3 had positive PCR and 69 had positive serological test. Population estimate of the number of SARS-CoV-2 infection and seropositivity were 2421 and 56,439, respectively, thus active infection rate (2.9/10,000) and the prevalence of prior SARS-CoV-2 exposure (68/10,000) was low. Self-reported loss of smell or taste and body aches were significantly more frequent among those with SARS-CoV-2. In this representative, cross-sectional survey of the Hungarian population with a high participation rate, the overall active infection rate was low in sync with the prevalence of prior SARS-CoV-2 exposure. We demonstrated a potential success of containment efforts, supporting an exit strategy. NCT04370067, 30.04.2020.