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

Merkely, Béla; Szabó, Attila J.; Kosztin, Annamária; Berényi, Ervin; Sebestyén, Andor; Lengyel, Csaba; Merkely, Gergő; Karády, Júlia; Várkonyi, István; Papp, Csaba; Miseta, Attila; Betlehem, József; Burián, Katalin; Csóka, Ildikó; Vásárhelyi, Barna; Ludwig, Endre; Prinz, Gyula; Sinkó, János; Hankó, Balázs; Varga, Péter; Fülöp, Gábor Áron; Mag, Kornélia; Vokó, Zoltán

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.