Viruses in Cambodian bird flu cases identified as endemic clade

Feb 26 (Reuters) – The viruses that infected two people in Cambodia with H5N1 bird flu have been identified as an endemic clade of bird flu circulating in the country, the US Centers for Disease Control and Prevention (CDC) said. United.

Cases reported last week had raised fears they were caused by a new strain of H5N1, clade 2.3.4.4b, which emerged in 2020 and caused a record number of deaths among wild birds and domestic poultry these last months.

But the work so far suggests that is not the case.

Preliminary genetic sequencing carried out in Cambodia led its Ministry of Health to identify the viruses as clade H5 2.3.2.1c, which circulated in Cambodia among birds and poultry for many years and sporadically caused infections in man, the CDC said in a statement on Saturday.

“Yes, this is an older clade of bird flu that has been circulating in the area for a number of years and although it has caused human infections in the past, it has not been found to “it was causing human-to-human transmission. However, that doesn’t mean the threat is less,” said Erik Karlsson, director of Cambodia’s National Influenza Center and acting head of virology at Cambodia’s Pasteur Institute, who sequenced the virus.

He added that the response must be coordinated and rapid to prevent further spread and limit exposure to any common source.

An investigation into the source and to detect any additional cases is ongoing, the CDC said, adding that so far there have been no indications of person-to-person spread.

Cambodia tested at least 12 people for the H5N1 strain last week, after an 11-year-old girl deceased of the virus in the first known transmission to humans in the country in nearly a decade.

The victim’s father, who was part of a group the girl had been in contact with in a province east of the capital Phnom Penh, tested positive for the virus but showed no symptoms, said Cambodian Health Minister Mam Bunheng said in a statement. Friday.

Only the daughter’s case has been sequenced and the father’s case is still being worked on, Karlsson said.

The World Health Organization said it was working with Cambodian authorities to track cases, describing the situation as disturbing due to the recent increase in cases in birds and mammals.

Reporting by Juby Babu in Bengaluru; additional reporting by Jennifer Rigby in London; edited by Barbara Lewis

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