Influenza A H5N1 Disease Acquired from infected poultry Person-to-person transmission rare Aggressive & severe disease in humans Mortality at least 60% Affects healthy young individuals Begins as a respiratory disease, progressing to a viral pneumonia and multi-organ failure Treatment may not prevent death ?Potential mortality in a pandemic
Controversy Balance the right to research with perceived ethical obligations Create a potential bio-weapon Provide data to terrorist organisations Risks of pathogen escape (small-pox, anthrax, influenza) Safety of the public What about military research When is research just to dangerous to conduct Does understanding the biology of infection in animal models really help ?
Pandemic vs Seasonal H1N1 (Pre-pandemic) VirusFerretsHumans Pandemic Mild Severe Fatal 30% sneezed No deaths Found in GI (70%) Generally mild Not associated with GI symptoms Lots of person-to-person transmission Spectrum of illness with some fatalities Some countries reported higher incidences or morbidity & mortality 50% sneezed 50% died Found in GI (20%) [& contacts] 10% sneezed No deaths Found in GI (10%) Seasonal100% sneezed No deaths No GI infection Generally mild No GI symptoms Fatalities occurred Q – How accurate was the ferret model in predicting human disease ?
Reality ? Ferret Model A(H3N2)v is easily transmissible Causes mild illness Human Cell Model A(H3N2)v > H3N2 Reaches a higher titre Observed Handful of cases (12) Mainly in young children Mild illness Few hospitalizations Low level of transmission thus far ? Pandemic potential? Not covered by the vaccine