An extensive, multi-agency public-health investigation into an avian influenza case involving a B.C. teenager has identified no additional cases nor evidence of human-to-human transmission.
The goals of the investigation were to identify any contacts who may have had exposure to the teenager, determine the source of exposure, and ensure that there was no risk of new infections from either the teenager or animal sources. The investigation also included testing of household pets, birds and other animals from nearby premises, and environmental (soil, water) testing.
To date, all tests on humans, animals and environmental samples related to this investigation have been negative for influenza H5. While it is reassuring that no further cases have been identified, officials have also not been able to definitively identify the source of the young person’s infection.
The investigation has determined the teenager was infected with the same strain of influenza H5N1 currently circulating in wild birds and poultry in B.C. (Clade 2.3.4.4b, Genotype D1.1). Advanced testing at the BC Centre for Disease Control (BCCDC) Public Health Laboratory determined the whole genome sequence of the virus most closely matches that of wild birds found in the Fraser Valley area in October and was not directly related to outbreaks at poultry farms in B.C.