I’m torn between wanting to ignore this story and wanting to attack the media reports on the study. I think I’ll compromise on a minimum set of complaints.
Firstly, the paper itself (“Deposition of respiratory virus pathogens on frequently touched surfaces at airports“) is more or less fine. The authors used real-time PCR to look for respiratory viruses on surfaces at airports. Seems fair, airport travel is certainly known to be associated with the risk of acquiring respiratory infections.
The results are seemingly not surprising… they only found viral signatures on 10 of 90 samples which doesn’t seem like a ton to me. Those tended to be surfaces that are touched the most frequently, most notably the security trays. They also tested a number of bathroom surfaces, without finding any viral signatures there.
Cue the headlines:
NYT “Airport Security Trays Carry More Cold Germs Than Toilets, Study Finds“. Or the ever informative “Airports Are Way More Disgusting Than You Think, New Study Finds“. And my personal favorite “Those Bins in the Airport Security Line Are Germ-Infested Cesspools“.
So here’s the rub:
-Finding DNA from viruses on a surface does not mean those viruses are viable
-Even if those viruses are viable, there’s no evidence here that they present any health risk (which the authors do point out)
-Toilets are a silly metric for germs (see my previous rant on this topic)… especially in this case! Respiratory viruses are typically spread through aerosols (coughing, sneezing) not through toilet activities.
So yeah, “germs” are everywhere… including things you touch at airports. You’ll be fine. Wash your hands before eating or sticking your fingers down someone’s throat.
A very sane perspective, thanks. One question – I thought it was still up unclear whether the dominant exposure route for respiratory viral inspections (I’m thinking of the flu) was through aerosols or through fomites. Is it mostly aerosols?
I had a recollection of folks telling me that it was aerosols, but I certainly could be mistaken. I’ve not checked out the literature for sure. Maybe I’ll ping Linsey Marr and ask her to respond.
From my reading of the literature, we still don’t know what the dominant exposure and transmission routes are for most respiratory infections. The medical community used to assume that contact transmission, either direct or indirect (involving fomites), was dominant, but more recent studies suggest that aerosol transmission may be at least as important. It’s very challenging to do a controlled study with human subjects, so we may not know anytime soon.
So happy that the building ecology community starts to pinpoint the difference between living, dormant and dead microbes!