A sample collected from a market in Hong Kong has tested positive for bird flu H9, days after a two-year-old boy who visited the venue contracted a mild strain of the infectious disease.
But the Centre for Health Protection (CHP) said on Monday that the risk of a serious bird flu outbreak was low.
The boy, who lives in Sha Tin, became ill after visiting Wo Che Market in the district and was later confirmed to be infected with H9N2 avian influenza, the centre said.
He was now in a stable condition, and six of his household contacts remained asymptomatic, according to authorities.
The centre’s Public Health Laboratory Services Branch conducted whole genome sequencing and analysis of the virus infecting the boy, confirming it was the low-pathogenic H9N2 strain with no significant genetic variations.
Seventeen environmental samples were collected from the boy’s home, the fresh provision shop at Wo Che Market he had visited and a park at Fung Wo Estate, all within Sha Tin.
One sample taken from a metal tray beneath a cage for live chickens used to collect droppings at the shop tested positive for the H9 bird flu virus, the centre said.
The remaining 16 samples were negative.
A centre spokesman said further analysis would be conducted on the positive sample.
“The CHP believed that it is more likely for the boy to have contracted H9 avian influenza by touching a contaminated surface at the fresh food shop selling live poultry in Wo Che Market,” he said.
Thorough disinfection and cleaning will be carried out at the shop.
The centre noted that the H9N2 strain had long been present in local poultry with low mortality rates in birds. The strain involved in this case had not shown evidence of human-to-human transmission or significant genetic variation, it noted.
Since 1999, Hong Kong has recorded 11 cases of people infected with H9N2, five of which were local. No deaths from the strain have been reported.
