Raw meat consumed by one of the infected cats in Poland has tested positive for H5N1 bird flu, according to researchers, adding to growing signs that a food product is behind the unusual outbreak.
At least 16 cats across Poland have died and tested positive for H5N1 avian influenza, but health officials are still investigating dozens of suspected cases, raising questions about the cause of the outbreak as cats are typically not affected.
“An assessment has shown that food is one of the likely routes of transmission of the pathogen,” virologist Krzysztof Pyrc said in a statement on late Monday night, together with fellow researchers Maciej Grzybek and Łukasz Rąbalski.
Earlier on Monday, Poland’s Veterinary Institute confirmed that genomic sequencing had shown that the strains in nine of the confirmed cases were closely related, and also very similar to a strain found in a white stork in the Tarnów region in early June.
“This indicates that feline H5N1 avian influenza viruses analyzed so far originate from a single, unidentified source, related to the H5N1 viruses circulating in wild birds in recent weeks in Poland,” the institute said.
In Monday night’s statement, the researchers said discussions with cat owners have led to raw meat as the possible source for the outbreak.
“To test this theory initially, we asked the owners of sick cats to submit samples of the meat they ate. As a result, we received five meat samples for testing,” they said. “The analysis showed that 1 of the 5 samples contained the virus. Further analysis showed that the meat contains not only the genetic material of the virus but also the infectious virus, and we were able to isolate the virus in cell culture.”