Parasites Parasites are not bacteria or viruses:
they’re animals, from single-celled protozoa
to large worms, that take up residence in one
or more animal “hosts” and use them for both
shelter and nourishment during parts of their
life cycle. There are more than 50 that can be
transmitted to people who eat fish raw or
undercooked, a handful of which are relatively
common, and may require surgery to remove.
Thanks to their more complex biological
organization, parasites are sensitive to
freezing (bacteria generally aren’t). So there’s
a simple rule for eliminating parasites in fish
and shellfish: either cook the food to a
minimum of 140ºF/60ºC, or prefreeze it. The
U.S. FDA recommends freezing at –31ºF/–
35ºC for 15 hours, or –10ºF/–23ºC for seven
days, treatments that are not feasible in home
freezers, which seldom dip below 0ºF.
Poisonings Caused by Toxic Algae