Dodgy mixed metaphors in Nature press releases aside, an important paper published this week and leaked by the media ahead of embargo expiration (tut, tut) reports how the first case of a domestic cat dying from the avian influenza H5N1 virus in Thailand in 2004 hit the airwaves.
Since then, numerous cases have emerged globally, including the death and euthanasia of 147 captive tigers fed virus-infected chicken carcasses. As feline fatalities increase scientists are now urging that the role cats might play in spreading avian influenza and the evolution of the virus ought to be reconsidered.
Albert Osterhaus and colleagues at Erasmus University in the Netherlands discuss the latest reports and experimental studies that underline the vulnerability of cats to H5N1 virus infection and the risks that cats pose to agencies fighting its global spread. They emphasise how cats can be infected with the virus through contact with domestic and wild birds, and then excrete the virus from the respiratory and digestive tract, sometimes transmitting infection to other cats. They also note that cats fed virus-infected chickens can be infected directly through the gut. This worryingly novel route for influenza transmission in mammals could be a serious cause for concern.
Despite this evidence, the authors argue that the impact of cats on the epidemiology of the avian influenza virus is still being overlooked by key organizations such as the World Health Organization (WHO).
The authors conclude that they cannot rule out the possibility of the virus mutating into a more dangerous strain in feline and other mammalian hosts, and suggest increased surveillance and precautions to be taken to prevent the virus leaping to humans.
More information in Nature this week.