Warsaw/Geneva: Several cats are found infected with avian influenza A(H5N1) unprecedentedly spread over a wide geographical area within any country, in Poland. Some cats developed severe symptoms including difficulty in breathing, bloody diarrhoea, and neurological signs, with rapid deterioration and death in some cases. In total, 20 of them had neurological signs, 19 had respiratory signs, and 17 had both neurological and respiratory signs.
The World Health Organization (WHO) said today that the source of the exposure of cats to the virus is currently unknown and epizootic investigations are ongoing. There are several possibilities for the source of infection, among which they could have had direct or indirect contact with infected birds or their environments, eaten infected birds, or eaten food contaminated with the virus. Authorities are investigating all potential sources and to date have not ruled out any. Of the 25 cats for which the information is available, two were outdoor cats, 18 were indoor with access to a balcony, terrace, or backyard, and five were indoor cats with no access to the outside environment. Seven cats are reported to have had the opportunity for contact with wild birds.
Genomic analysis of 19 viruses sequenced from this outbreak showed that they all belonged to the H5 clade 2.3.4.4b and were highly related to each other. Also, the viruses are similar to influenza A(H5N1) clade 2.3.4.4b viruses which have been circulating in wild birds and caused outbreaks in poultry recently in Poland.
It was on June 27, 2023, when the International Health. Regulations (IHR) National Focal Point of Poland notified WHO of unusual deaths in cats across the country. WHO said as of July 11, 2023, out of the 47 samples that were tested from 46 cats and one captive caracal, 29 (62%) were found to be positive for influenza A (H5N1). Fourteen cats were reported to have been euthanized, and a further 11 died, with the last death reported on June 30, 2023. Post-mortem exams on a small number of cats suggested pneumonia.
Incidentally, as of July 12, no human contacts of A(H5N1) positive cats have reported symptoms, and the surveillance period for all contacts is now complete, WHO said today. It stated that the risk of human infections following exposure to infected cats at the national level is assessed as low for the general population, and low to moderate for cat owners and those occupationally exposed to H5N1-infected cats (such as veterinarians) without the use of appropriate personal protective equipment.
Previously there have been reports of sporadic infections in domestic cats with A(H5N1) viruses, including A(H5N1) H5 clade 2.3.4.4b, caused due to the close contact of the cats with infected birds or from ingesting meat of infected birds. However, the spread of influenza among cats in Poland is the first time ever over such a wide area that covers 13 geographical regions of the country.
WHO said it has been monitoring the situation and working in close collaboration with the animal and public health sectors, regional agencies, the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (WOAH), and other partner agencies in Poland.
It may be noted that since the end of 2021, an unprecedented number of H5N1 outbreaks among poultry and wild birds has been reported worldwide. As of June 2023, the clade 2.3.4.4b viruses have become dominant in Asia, Europe, the Americas and Africa. Alongside wild bird and domestic poultry infections, there have been increased detections in non-avian species, including wild terrestrial (often scavenging) and marine mammals and occasionally in farmed or captive mammalian species, likely through contact with infected live or dead birds or their environments.
– global bihari bureau
