Concomitant hemorrhagic fever with renal syndrome and COVID-19

Udmurt Republic is an endemic region for hemorrhagic fever with renal syndrome (HFRS). An extremely high incidence of COVID-19 in 2020-2021 worldwide and in Udmurt Republic in particular suggests that patients might bear these two infections simultaneously. In this article, we report a case of mixed COVID-19 plus HFRS infection. Specific clinical manifestations of HFRS in a COVID-19-coinfected patient included long-term fatigue, thrombocytopenia, iso(hypo)sthenuria, polyuria, episodes of sinus tachycardia and hypertension. On the other hand, the main clinical characteristics of COVID-19 in a HFRS-coinfected patient included no clinical signs of respiratory failure and relatively high saturation despite a substantial lung damage. In general, mixed infection is a risk factor that aggravates the disease and can worsen outcome. However, simultaneous infection of a cell with more than one virus probably causes viral interference, which results in suppression of one or both viruses. Key words: COVID-19, hemorrhagic fever with renal syndrome, viral interference