Edinburgh Research Explorer

Is the minimum infective dose of COVID-19 small?

Press/Media: Expert Comment

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.

Period1 Apr 2020

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.

References

TitleIs the mimimum infective dose of COVID-19 small?
Media name/outletMetafact
Date of coverage1/04/20

ID: 142694069