The first three months of the COVID-19 epidemic: Epidemiological evidence for two separate strains of SARS-CoV-2 viruses spreading and implications for prevention strategies

Knut M. Wittkowski

The epidemiological data does not support the hypothesis that SARS-CoV-2 spread from Munich in Germany to Italy. (Kupferschmidt 2020) Instead, the virus may have spread from Italy to its neighboring countries, Switzerland, France, Spain, Austria, and Slovenia, within just a few days of arriving from Iran. The top incidence seems to be less than half of that in Italy and the lethality is lower, too. While Italy has many people 65 years and older (23%, second only to Japan data.worldbank.org/indicator/SP.POP.65UP.TO.ZS ), the relatively small differences or age distribution within Europe (e.g., Germany: 21%) are unlikely to account for much of this difference. A possible explanation (indicated in Fig 6) is that the less virulent strain(s) arriving from other parts of Asia may have had a head . CC-BY-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.