Why Is a Deadly Cat Parasite Attacking Arctic Belugas?
A common parasite carried by almost all cat species, otherwise known as the kitty litter disease, has made a surprising appearance in western Arctic beluga whales, according to researchers from the University of British Columbia (UBC).
Cats are considered a “definitive” host for Toxoplasma gondii, where the parasite can lay eggs that are shed in cats’ feces. According to researchers, it’s typically spread by consuming undercooked meat or water that has come in contact with soil contaminated by cat feces.
In this case, they suspect the outbreak was caused by infected cat feces washing into waterways before flowing into the sea, where fish and other marine organisms became contaminated before eventually being eaten by the whales, reports the Guardian.
Although many people can be carriers and remain unaffected, T. gondii is believed to be the leading cause of infectious blindness worldwide and poses the biggest risk to pregnant women and animals and people with compromised immune systems, where it can potentially be fatal.
The infected belugas were discovered as part of a long-term study that involves screening marine mammals for microbes in a search for climate-change related changes that could lead to disease. The parasite was discovered in tissue samples that were taken from belugas who were part of traditional Inuit hunts and marks the first time an infectious form of T. gondii has been found in the region after 14 years of sampling.
Researchers from the UBC’s Marine Mammal Research Unit presented their findings at the American Association for the Advancement of Science last week and believe that warmer temperatures in the Arctic has led to the movement of new pathogens that haven’t been seen before.
Cold temperatures and ice sheets have kept pathogens from moving north, but warmer temperatures in the Arctic have not only allowed new pathogens to move in, but the “big thaw” happening now has also allowed for pathogens from the north to move south and cause infections.
“Ice is a major eco-barrier for pathogens,” Michael Grigg, a molecular parasitologist with the U.S. National Institutes of Health and an adjunct professor at UBC, said in a statement. “What we’re seeing with the big thaw is the liberation of pathogens gaining access to vulnerable new hosts and wreaking havoc.”
In separate work, these researchers also identified a parasite, Sarcocystis pinnipedi, that originated in the Arctic and moved south. This new strain was responsible for a die-off of grey seals in Nova Scotia in 2012, in addition causing the deaths of an endangered Steller sea lion, seals, Hawaiian monk seals, walruses, polar and grizzly bears in Alaska and as far south as British Columbia.
Although no sick belugas have been discovered yet, the findings pose major health concerns for local communities and those who eat whale meat are being advised to thoroughly cook the meat and take extra precautions.
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