Cat litter killing whales, dolphins, porpoises
Pet owners who flush used cat litter down the lavatory may be responsible for the deaths of whales, dolphins and porpoises around Britain's coast, according to academics and public health experts.
They have found evidence of a common parasite in dead marine mammals and say family cats could be be the unwitting source. Cats are essential to the life cycle of toxoplasma gondii, which can infect most mammals and birds but only as part of the food chain.
The possible link to dolphin deaths has been raised by staff from Swansea and Glamorgan universities and the National Public Health Service for Wales in a letter to the Veterinary Record. They say that in California concern that cat faeces have contributed to sea otter deaths has led to disposal warnings on bags of cat litter. But little is known about infection in marine species around Britain.
Blood samples from dead stranded cetaceans revealed infection in one in 70 harbour porpoises, in six of 21 common dolphins and in the only hump-backed whale tested. Nearly one in eight Swansea University and health service employees admitted flushing cat litter away.
During the first few weeks, the infection typically causes a mild flu-like illness or no illness. After the first few weeks of infection have passed, the parasite rarely causes any symptoms in otherwise healthy adults. However, people with a weakened immune system, such as those infected with HIV, may become seriously ill, and it can occasionally be fatal. The parasite can cause encephalitis (inflammation of the brain) and neurologic diseases and can affect the heart, liver, and eyes (chorioretinitis).