Adaptation of a Russian population to SARS-CoV-2: Asymptomatic course, comorbidities, mortality, and other respiratory viruses – A reply to Fear versus Data

This study was conducted to assess the spread of SARS-CoV-2 in Russia and the adaptation of the population to the virus in March to June 2020. Two groups were investigated: 1) 12 082 individuals already proven positive for SARS-CoV-2 (clinical information was studied); 2) 7864+4458 individuals with suspected respiratory infections (polymerase chain reaction [PCR] tests and clinical information were studied). In the latter, SARS-CoV-2-positive individuals comprised 5.37% in March and 11.42% in June 2020. Several viral co-infections were observed for SARS-CoV-2. Rhinoviruses accounted for the largest proportion of co-infections (7.91% of samples were SARS-CoV-2-positive); followed by respiratory syncytial virus (7.03%); adenoviruses (4.84%); metapneumoviruses (3.29%); parainfluenza viruses (2.42%); enterovirus D68 (1.10%) and other viruses (entero-, echo-, parecho-) (<1%). Average SARS-CoV-2 case fatality rate in the group of 12 537 individuals was determined to be 0.6% (in contrast to official Russian government statistics of 1.5% mortality). This rate is within the range of mortality caused by other common seasonal respiratory viruses (0.01-2.21% in Russia in 2012 to 2020). Most fatalities occurred in individuals with comorbidities, as for other respiratory viruses. The proportion of SARS-CoV-2 asymptomatic carriers was 56.68% in March and 70.67% in June 2020. This new pathogen presents a substantial risk to human beings as it was not contained at the start of its outbreak in Wuhan and spread worldwide. However, surveillance, prevention and treatment must be strictly evidence-based and not dictated by fear.