北极白鲸体内发现猫类寄生虫

University of British Columbia scientists have found for the first time an infectious form of the cat parasite¹ Toxoplasma gondii in western Arctic Beluga, prompting a health advisory² to the Inuit people who eat whale meat. The same team also discovered a new strain of the parasite, previously³ sequestered⁴（隐退） in the icy north, that is responsible for killing⁵ 406 grey seals in the north Atlantic in 2012.   Presenting their findings today at the 2014 Annual Meeting of the American Association for the Advancement⁶ of Science (AAAS), Michael Grigg and Stephen Raverty from UBC's Marine⁷ Mammal Research Unit say that the "big thaw⁸" occurring in the Arctic is allowing never-before-seen movement of pathogens（病原体） between the Arctic and the lower latitudes⁹.   "Ice is a major eco-barrier for pathogens," says Michael Grigg, a molecular¹⁰ parasitologist with the U.S. National Institutes of Health and an adjunct professor at UBC. "What we're seeing with the big thaw is the liberation of pathogens gaining access to vulnerable new hosts and wreaking¹¹ havoc¹²（肆虐）."   Toxoplasmosis, also known as kitty litter disease, is the leading cause of infectious blindness in humans and can be fatal to fetuses¹³ and to people and animals with compromised immune systems.   "Belugas are not only an integral part of Inuit culture and folklore¹⁴, but also a major staple¹⁵ of the traditional diet. Hunters and community members are very concerned about food safety and security," says Raverty, a veterinary pathologist with the B.C. Ministry¹⁶ of Agriculture and Lands' Animal Health Centre and an adjunct professor at UBC. Raverty has led the systematic¹⁷ sampling and screening of hunter-harvested Beluga for 14 years.   Grigg has also identified the culprit of the 2012 grey seal die-off as a new strain of Sarcocystis. While not harmful to humans, the Arctic parasite, which was named Sarcocystis pinnipedi at the AAAS meeting today, has now killed an endangered Steller sea lion, seals, Hawaiian monk¹⁸ seals, walruses¹⁹（海象）, polar and grizzly²⁰ bears in Alaska and as far south as British Columbia.