Trichinella spiralis

1
Trichinella spiralis

• Daniel Jackson

2
Review of Trichinella spiralis

• Contracted by eating raw or undercooked pork or
  wild game with larvae in muscle
• Causes trichinosis
• Hosts pigs, bears, rats, walrus, wolves,
  scavenging animals, and humans

3
Historical Accounts

• Late 1800s found in Egypt
• Mummies
• Alaskan Eskimos

4
History of T. spiralis

• James Paget
• 1st yr student at the London Medical School
• Feb. 2, 1835, autopsy of 51 yr old Italian
  bricklayer
• sandy diaphragm

5
History of T. spiralis cont

• Richard Owen
• Assistant curator to the Royal College of
  Surgeons
• Heard about Pagets findings
• Drew pictures and submitted them to the Royal
  Society

6
History of Life Cycle

• Rudolph Virchow
• German pathologist
• Between the mid 1850s to late 1870s discovered
  the life cycle of Trichinella spiralis
• Witnessed another cadaver with white flecks and
  confirmed that it was Trichinella spiralis
• Fed a large quantity of meat to his dog
• Dissected the dead dog four days later and found
  adult worms in the digestive tract

7
Cultural Practices and T. spiralis

• Eating raw or undercooked pork
• In Thailand, 200-600 more cases are reported
  around the Thai New Year because of the
  consumption of communal pork
• Delicacy in some parts of Europe

8
Distribution
In Eastern Europe some swine herds have over 50
trichinosis infection rates
9
Infrastructure

• Ecosystem utilization
• Source of food
• Humans and animals
• International trade of meats
• Legislation prohibiting feeding of raw meats to
  animals
• Increased commercial and home freezing of pork
• Public awareness

10
Treatments for T. spiralis

• Animals
• Ivermectin
• Febendazole
• Humans
• Thiabendazole
• No side effects
• Food preservative

11
Preventing T. spiralis

• Cook meat until juices run clear or internal
  temperature is 144º Fahrenheit
• Freeze pork less than 6 inches thick
• 20 days at 5º F
• 3 days at -4º F
• Cook wild game thoroughly
• Dont allow hogs to eat uncooked carcasses
• Curing, drying, smoking or microwaving meat
  doesnt kill worms

12
Anthropogenic Effects

• Economic development
• Education
• Habitat transformation
• Loss of habitat leads to a decrease in animal
  hosts

13
References

• http//www.trichinella.org/
• http//www.stanford.edu/class/humbio103/ParaSites2
  005/Trichinella/
• http//www.cdc.gov/ncidod/dpd/parasites/trichinosi
  s/factsht_trichinosis.htm