It is rare in the US but where it still occurs it has been traced
to the consumption rady to eat pork sausage. It is absent in France
as pigs are fed root vegetables there. Farmers here infect their swine
by feeding them raw garbage. It is killed by thorough cooking or
freezing (-15 degrees C for a week or -18 C. for 24-hours). Interestingly,
larvae from Trichina obtained from arctic mammals survive colder temperatures
than larvae from temperate and warm regions. Eating improperly cured
or cooked pork products is not the only way you can get trichinosis.
Eating improperly cooked bear meat and the flesh of some marine mammals
can also infect you.
Unscrupulous farmers who feed their swine raw garbage don't care if they
infect their animals sinced they are going to be slaughtered anyway.