Вы что-то путаете, вирусы от холода (и морозов) не дохнут, только от высоких температур. Influenza A viruses can survive:-Over 30 days at 0°C (32.0°F) (over one month at freezing temperature)-6 days at 37°C (98.6°F) (one week at human body temperature)-decades in permanently frozen lakes-on hard non-porous surface such as plastic or stainless steel for 24–48 hours-on clothes, paper and tissues for 8–12 hours[6]