Extremely toxic flu jumps species, cats die en masse: WHO assesses the risk in humans

According to a document Nguoi Lao Dong Newspaper received from WHO on the afternoon of July 17 (Vietnam time), the unprecedented outbreak of influenza A/H5N1 in cats was notified to WHO by Poland from June 27.

As of July 11, a total of 46 cats and one captive hyena have been sampled for testing. 29 samples tested positive for influenza A/H5N1, commonly known as highly pathogenic avian influenza .

This is the first time highly pathogenic avian influenza A/H5N1 has been detected en masse in cats, over a large area of ​​a country. Previously, this type of flu rarely spread to mammals - (Illustration from the Internet).

A total of 25/29 infected cats died. The source of the cat's infection with the virus is currently unknown and epidemiological investigations are ongoing.

This is a very unusual outbreak . Influenza A/H5N1 was previously commonly found in poultry and wild birds. Since the beginning of this year, WHO has warned about the unusual "species jump" of this type of flu , infecting a number of mammals that have never been recorded to be infected with this toxic type of flu.

As for cats, there have been reports of sporadic cases in previous years, but this is the first report of large numbers of infected cats over a large geographic area of ​​a country.

As of July 12, no people exposed to cats with influenza A/H5N1 have reported symptoms, and the surveillance period for all contacts is now complete.

WHO's national assessment of the risk of infection in humans following exposure to infected cats is considered low for the general population.

The agency also warns of a low to moderate risk for cat owners and those who have professional contact with cats infected with H5N1 (such as veterinarians) without using personal defense measures. Fit.

WHO continues to monitor the situation and work closely with the veterinary and public health sectors, regional agencies, the Food and Agriculture Organization of the United Nations (FAO), the World Organization for Animal Health (WOAH) and other partner agencies in Poland.

The A/H5N1 influenza virus strain that infected the cats above is clade 2.3.4.5b, which has circulated in Poland in previous wild bird outbreaks.

The source of infection with influenza A/H5N1 that causes disease in cats has not yet been determined . WHO hypothesizes include direct or indirect contact with infected birds/poultry.

WHO Director-General Tedros Adhanom Ghebreyesus emphasized in a press conference in February 2023 that it is necessary to closely monitor the spread of highly pathogenic avian influenza A/H5N1 in the context that it appears to be unusually invasive. new host type.

Since the beginning of the year, Cambodia and the UK have also reported influenza A/H5N1 in humans . Both clusters of cases (each cluster of 2 people) were transmitted from animals, and human-to-human transmission has not been detected. One patient in Cambodia died despite receiving intensive treatment.

Influenza A/H5N1 is an extremely virulent type of flu , a dangerous pathogen that all member countries are required to report to WHO even if only 1 case is detected. In Vietnam, influenza A/H5N1 is considered a group A infectious disease (the most dangerous).

This is also one of the most worrying pathogens threatening the livestock industry around the world, tending to spread from the end of 2022.