[SARS-CoV-2, influenza and norovirus infection : A direct epidemiologic comparison]

Hospitalization rates (HR), emergency care prevalence (ECP) and case fatality proportions (CFP) of hospitalized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) patients in one municipality have not been studied, including how these differ from other pandemic or seasonal viral diseases, such as influenza A/B or norovirus. These analyses and their comparison with negative-tested hospitalized patients are the purpose of the present study.

A total of 67,000 cases of hospitalized patients of a tertiary care hospital and data of the regional health institute were analyzed to calculate HR, ECP and CFP of SARS-CoV‑2, influenza A/B and norovirus genotype 1/2.

In the city and district of Fürth (Germany), 824 persons (0.34%) tested SARS-CoV-2-positive through 7 May 2020, 162 of whom (19.7%) were hospitalized. Furthermore, 48 out of 91 patients died in hospital (CFP 11.0%). During the flu/norovirus season 2019/2020 992 inhabitants were flu-positive and 135 norovirus-positive, of whom 202 (20.3%) and 125 (91.9%), respectively, were hospitalized. The ECPs were 4.1%, 2.0% and 0.6%. The CFPs of the SARS-CoV-2-, influenza- and norovirus-positive hospital cohort were 29.1%, 3.0% and 1.6%, while CFPs of the negative-tested were 5.9%, 4.8% and 6.9% with an in-hospital mortality of 2.1% for 2020.

While HRs of SARS-CoV‑2 and influenza were similar, CFPs differ significantly. CFPs of negative-tested patients were comparable between the three infectious diseases.