Trichinella spirosis (trichinellosis, trichina worm, trichinosis)

General: Found in a wide variety of carnivores & omnivores, though most classically in swine. It is spread via the ingestion of juvenile (infective) larvae in undercooked meat. Processed swine in the U.S. has an infective rate of ~1%, which is almost always cooked adequately to prevent human infection. Modern day outbreaks are typically traced to private slaughterhouses or hunted wild animals (especially bear).

Clinical: May cause nonspecific muscle soreness. Not considered fatal, but may cause extreme discomfort.

• Normal:
• Abnormal:

Resistance:

Morphology:

Growth characteristics: The normal life cycle is:

• Ingestion of juvenile infective larvae
• Larvae mature into adults in the host's small intestine
• Female adults give birth to larvae
• Larvae may enter the circulation and lodge in the host's skeletal muscle, where they mature into infective larvae; this may produce severe muscular soreness
• Infection is passed on by ingestion of infected muscle

Common/important pathogens: