Poland confirmed on Monday the presence of the virulent H5N1 in two dead swans and Austria reported that a cat from an animal sanctuary was tested positive for the infection, but has not yet shown any symptoms. The cat was kept with other 170 in cages, next to a group of birds including a swan which died of the disease; also chicken and ducks were found to carry the deadly strain. All 170 cats are under quarantine, being closely monitored. Saliva samples taken from 40 of them confirmed the virus only in one. The remaining cats and dogs will be tested for the infection. Poland also found two dead swans carrying the H5N1 virus; the veterinary institute has confirmed the infection. The World Health Organization stated that so far there is no known case of a cat infecting a human and there is much to be studied about the cat's role in transmitting the virus. Animals which carry the virus and show no symptoms make scientists' work more difficult. The risk of mutation increases with the time the virus spends in a mammal. Still, bird flu is essentially an animal disease which is transmitted to humans only through close contact. The virus can mutate and officials fear that it could transform into one transmitted from human to human. China confirmed Sunday the 95th death due to bird flu in the southern province Guangdong, bordering Hong Kong. Europe's poultry industry has taken a severe hit. France, Europe's largest producer, is losing $48 million a month after the infection of farm birds, leading to the import ban from more than 40 countries.