Infectivity of Trichinella nativa in Traditional Northern (Country) Foods Prepared with Meat from Experimentally Infected Seals

Abstract

The infectivity of Trichinella nativa larvae in three traditional northern (country) foods was assessed. Foods were prepared with meat from seals experimentally infected with Trichinella nativa and evaluated over a 317-day period during which this food was fed directly to cats while mice were orally inoculated with larvae recovered following the digestion of the food in a solution containing 1% pepsin and 1% HCl at 37°C. Foods examined were igunaq (meat and blubber placed in a seal skin bag and allowed to ferment), nikku (air-dried meat), and sausage (meat, fillers, salt, and spices). Sausage was examined both in a raw state and after partial cooking. Infective T. nativa larvae survived in igunaq, nikku, raw frozen sausage, and poorly cooked sausage for at least 5 months under controlled laboratory conditions. Core temperatures of partially cooked sausage never exceeded 50°C. Caution should be exercised in using these data to establish guidelines for the consumption of raw products, since the survival of infective larvae could be unpredictably extended under field conditions. These data indicate significant food safety risks associated with igunaq, nikku, and sausage prepared with Trichinella-infected meat and provide information for use in risk management and in directing future research.