E-DRUG: Not a bird, but a swine flu pandemic? (2)
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It is an outbreak not a pandemic. So far new influenza virus subtypes caused by an antigenic shift such as A/H5N1, A/H3N1, AH1N2, A/H9N2, A/H3N2 and A/H7N7 some of these through recombination with types common in e.g. pigs or birds, are associated with a pandemic potential (population 100% susceptible).
Variants are a result of antigenic drifts (such as this one of H1N1?) and have as subtype been around in humans (Spanish flu) and should according the literature be limited to epidemic patterns.
Flu variants occur almost yearly, whereas shifts (new subtypes) occur more infrequently (1918, 1957, 1967/68, 1977, 1997, 2003, ....)
Interestingly however is further that contrary to the neuraminidase inhibitors (oseltamivir etc) effective against type A and type B, amantadine is known NOT to be effective against Influenza type B. Could that point towards type A/B (co-)presence in the cases? On the other hand type B is known for antigenic drifts only no shifts (no subtypes, only variants).
Pigs seem to harbor multiple subtypes including avian types and those acquired from humans..Therefore as stated in the same message if the virus is indeed genetically the same as a [new] strain of swine flu, designated H1N1 than that would be somehow re-assuring in terms of pandemics
With kind regards
Pascal Verhoeven
verhoeven.pascal@gmail.com
Tel +31 634041441