A Messy Story - The Monster at Our Door: The Global Threat of Avian Flu - page 28

daughter's bedside, was also stricken and died in mid-February, nine days after his return to Hong Kong;
his eight-year-old son developed critical symptoms of respiratory distress but ultimately recovered. 112
Both father and son were confirmed to have been infected with the same strain of H5N1 that was killing
ducks in the parks. Genetic sequencing revealed that it was a remote cousin to the original 1997 strain.
The hemagglutinin was derived from the same lineage, but the internal proteins and neuraminidase had
evolved elsewhere. Some researchers surmised that the influenza had been contracted in Fujian—the fam-
ily's relatives kept chickens—and were skeptical of China's claim that it had not experienced any large-
scale outbreaks of avian influenza among ducks or poultry. 113 In any event, experts were troubled by fur-
ther evidence of increasing virulence in the rapidly evolving H5N1 family. WHO went to pandemic alert
status, and public-health officials again buckled their seatbelts.