There are case reports of individuals with incubation periods of 27 days and 19 days.
The most likely explanation for a 27 day incubation period seems to me that an untraced secondary infection happened. Do we know that people have evidence to rule out such a secondary infection?
This is certainly possible, and it will never be possible to fully rule out second exposures in cases like this. But note that the 19- and 27-day outliers were not included in the data used by the linked paper that estimated a >14day right tail, and I think it’s unlikely for untraced second exposures to have influenced its conclusion.
There are cases where you can know which exposure is responsible because you did RNA sequencing and can use the mutations to trace the route of infection. Given that we however don’t have cheap enough RNA sequencing to widely deploy it, it seems to me unlikely that the 27-day outlier is backed by such considerations.
The most likely explanation for a 27 day incubation period seems to me that an untraced secondary infection happened. Do we know that people have evidence to rule out such a secondary infection?
This is certainly possible, and it will never be possible to fully rule out second exposures in cases like this. But note that the 19- and 27-day outliers were not included in the data used by the linked paper that estimated a >14day right tail, and I think it’s unlikely for untraced second exposures to have influenced its conclusion.
There are cases where you can know which exposure is responsible because you did RNA sequencing and can use the mutations to trace the route of infection. Given that we however don’t have cheap enough RNA sequencing to widely deploy it, it seems to me unlikely that the 27-day outlier is backed by such considerations.