Clearing the Air Around Influenza

Transmission

This is a simplified version of our work on the evidentiary rules for establishing causality or the chain of transmission of respiratory viruses. Universally accepted rules are badly needed, as, in their absence, the chaos we saw during the recent pandemic will hinder our proper understanding of the ecology of respiratory viruses and our efforts to do something about them.

The complete study and hierarchy are available as a PDF at the end of the post for those who want to read more.

Another aspect of the puzzle is the mode of transmission of these respiratory agents. From the 1950s onwards, many experiments were carried out to try and understand precisely how you could end up with, say, an adenovirus “Flu.” Transmission may occur in many ways, from body fluids (sneezing, droplets, aerosols) to contact or even faeces. However, when quarantined volunteers are purposely exposed to known agents, challenge studies have given equivocal results, and transmission is not linear or 1 to 1.

Before …