Foodborne Animal Parasites 699
Figure 29–3 Reported cases of trichinellosis by year, United States, 1970–2000 (CDC, 02).
Symptoms and Treatment
One to 2 days after the ingestion of heavily encysted meat, trichinae penetrate the intestinal mucosa,
producing nausea, abdominal pain, diarrhea, and sometimes vomiting. When only a few larvae are
ingested, the incubation period may be as long as 30 days. The symptoms may persist for several days,
or they may abate and be overlooked. The larvae begin to invade striated muscles about 7–9 days after
Table 29–3 Outbreaks of Trichinellosis Among Patients, by Year, State, Number of Cases, Month
of Illness Onset, and Implicated Meat—United States, 1997–2001
88
Year
State
No. of Cases
Month of Illness Onset
Implicated Meat
1997
Montana
5
December
Bear jerky
1998
Ohio
8
October–November
Bear roast, ground bear meat
1999
Illinois
2
March–May
Pork sausage, pork jerky
2000
Illinois
2
January
Pork sausage, smoked pork
2000
Alaska
4
August–September
Bear steak (fried)
2001
California
2
May
Home-raised pork
2001
California
6
May–June
Home-raised pork (raw)
2001
California
2
August
Bear
2001
California
2
November
Bear
Total
33