Title Is the mimimum infective dose of COVID-19 small? Media name/outlet Metafact Country United Kingdom Date 1/04/20 Description Although the new coronavirus can survive up to 3 days on certain surfaces, the risk is only high depending on the virus load needed to catch COVID-19.
The infective dose, or more specifically the ID50, is the estimated number of organisms or virus particles required to produce infection in 50% of normal adult humans exposed by a given route.
Do we know if it's small or large?
We do not yet know what the infectious dose is for SARS-CoV-2/COVID-19.
Extrapolating from influenza virus, where we know a lot more, the infectious dose by breathing it in (a direct journey from one person to another through droplets released in a cough) might be quite small. However, infection via a contaminated surface – where the virus has to survive a period of drying out, then a journey from surface to hand to face, is likely to require a lot more.
So maintain social distancing as much as possible, but following simple hand hygiene rules should take care of any risk from handling packages and groceries.
Persons Paul Digard