EID Journal: Co-Infection by Influenza Strains

[indigo girl]

EID Journal: Co-Infection By Influenza Strains

So, why should we care? Well, for one thing because stuff happens like antiviral resistance, for example. Here is a scenario showing one way for this to happen:

During the opening days and weeks of the pandemic in 2009, clinical samples in New Zealand were first screened for Influenza A, and then if positive, tested for the novel H1N1 virus.

Testing for seasonal H1N1 and seasonal H3N2 were only done if a sample tested positive for influenza A, but negative for the pandemic virus.

Unexpectedly, some viral cultures that tested positive for novel H1N1 also appeared to show resistance to oseltamivir (Tamiflu).

Further investigation revealed that the pandemic virus was not resistant, that the samples contained both novel H1N1 and a resistant seasonal H1N1 virus.

A serendipitous discovery that led researchers to conduct secondary rRT-PCR testing for seasonal H1N1 on 1,044 clinical samples that had already tested positive for the pandemic virus.

The authors state that the rate of co-infection could actually be higher, since samples were not checked for any other flu strains such as H3N2 and influenza B.

Still, this research suggests that humans, like swine, could be `mixing vessels’ for influenza. How often this sort of gene swapping actually occurs in humans remains unknown.