Avian influenza A (H7N9) virus: Can it help us more objectivelyjudge all respiratory viruses?

Avian influenza A (H7N9) virus: Can it help us more objectivelyjudge all respiratory viruses?

Avian influenza A (H7N9) virus: Can it help us more objectivelyjudge all respiratory viruses?

The World Health Organization alerted the public to the emer-gence of a new “bird flu” outbreak caused by human infection witha novel avian influenza A (H7N9) virus on March 31, 2013. Caseswere defined initially by pneumonia, <7 day incubation period andRT-PCR positivity. Deaths quickly accrued in the days immedi-ately following – before validated testing was available and in theabsence of general screening. Cases usually presented with fever,cough and wheeze, progressed to severe disease and hospitaliza-tion because of pneumonia, acute respiratory distress syndrome,septic shock and multi-organ failure. An alarmingly high apparentcase fatality ratio (CFR; using total confirmed cases as the denomi-nator, Fig. 1) could be calculated, with 36 fatalities from 132 cases(as of 20th May; 27%).