Which of the following animals would be most likely to serve as a source of Trichinella spp. infection to humans in the U.S.?

The most likely source of Trichinella spp. infection to humans in the U.S. is indeed bears. Trichinella spiralis, the most common species associated with human infection, is often transmitted through the consumption of undercooked or raw meat from infected animals. In the U.S., while pigs are a well-known source of Trichinella, bear meat has been identified as a significant risk, especially in regions where bear hunting is prevalent.

Bears are omnivores and can acquire Trichinella through their diets, which may include other infected wildlife. The larvae can develop in bear tissue, and as such, consuming improperly cooked bear meat poses a legitimate risk for human infection. Additionally, cases of trichinosis from consuming bear meat have been reported, highlighting their role as a source of this parasite.

Pigs, while also important historically as a source of Trichinella, have seen decreased incidence of the parasite in the U.S. due to improved farming practices and regulations regarding feeding practices. Deer and raccoon can carry Trichinella as well, but bears in certain areas present a more notable risk due to hunting and consumption patterns.

Overall, while all these animals can be reservoirs of the