 |
Trichinosis -- Hawaii
In January 1986, three cases of trichinosis were reported to
the
Hawaii Department of Health. The cases occurred among persons who
had
eaten wild boar meat given to them by a local Hawaiian who had
killed
the animal. Because the meat had been distributed among several
family members and friends of the hunter, an investigation was
conducted to determine the extent of the outbreak.
Among all of those who had received some of the wild boar,
health
officials identified 28 persons who had eaten the meat. Seven of
them
were not available for follow-up; the remaining 21 persons were
interviewed on February 21 and 22, 1986. Seven (33%) of these had
illnesses that met the standard case definition for trichinosis
(1).
All seven patients had at least four of the following symptoms:
myalgia (7), malaise (7), fever (6), headache (6), diarrhea (4),
nausea (4), periorbital edema (4), vomiting (2), and trunk and limb
edema and cutaneous rash (1). The patients ranged from 13 to 55
years
of age (mean = 32 years); five (71%) were male. All were of
Hawaiian
or Asian decent. Dates of ingestion ranged from January 9 to
January
22; dates of onset of symptoms ranged from January 31 to March 1.
The
median incubation period was 26 days, and the median duration of
illness was 14 days. One patient was hospitalized; three were
treated
with mebendazole, and two were treated with thiabendazole. All
patients recovered.
Serum was drawn from all seven patients during a time period
that
ranged from 50 and 81 days after ingestion of the implicated meat.
There was serological evidence of infection in five of these
patients
(titers greater than or equal to 40 by the bentonite flocculation
test). Laboratory studies of four patients seen by a physician
during
acute illness revealed eosinophilia ranging from 8% to 55%.
Samples of the implicated wild boar meat were sent to the
Centers
for Disease Control for study. An artificial digestion procedure
performed on the meat revealed from 2 to 9 Trichinella larvae per
gram
of the frozen meat.
Four of the 21 persons interviewed ate the meat after it had
been
microwaved at high heat for 2 minutes; the remaining 17 persons ate
the meat fried. All four of those eating microwaved meat became
ill;
and three (18%) of those who had eaten fried meat became ill (p =
0.01, RR = 5.7). Inadequate recall and incomplete responses
prevented investigators from looking at dose response for illness.
However, the two people with the most severe illness had eaten the
largest amounts of wild boar meat.
All remaining portions of the wild boar meat were confiscated.
In
addition, all persons who had eaten the meat were instructed in the
proper handling and preparation of pork products.
Reported by EL Lyons, DVM, MS, CK Wakida, AP Liang, MD, MPH, State
Epidemiologist, Hawaii Dept of Health; Helminthic Diseases Br, Div
of
Parasitic Diseases, Center for Infectious Diseases, Div of Field
Svcs,
Epidemiology Program Office, CDC. Editorial Note
Editorial Note: Trichinella spiralis continues to be a persistent
public health problem in the United States. During the period
1975-1985, pork (including wild boar) was implicated in 78.7% of
the
reported cases in which the implicated meat item was identified.
Other wild animal meat was implicated in 13.8% of the reported
cases,
and ground beef, in 6.7%. During the same time period, only 19
(1.6%)
of the reported cases of trichinosis were associated with wild boar
meat. Hawaii reported nine cases, eight of which were associated
with
consumption of wild boar meat (1,2).
In the present outbreak, three cases were associated with fried
wild pork sausage that was undercooked. Four cases were associated
with wild pork sausage prepared in a microwave oven; however, the
procedures used were not compatible with those generally
recommended
by microwave oven manufacturers or pork interest groups for safe
microwave cooking of pork (3). The U.S. Department of Agriculture
has
recommended cooking pork in a microwave oven until it attains a
temperature of 76.7 C (170 F) throughout. Improper cooking of meat
in
a microwave can result in variability of internal temperatures in
the
meat, with the result that there will not be proper inactivation of
bacteria and other potentially disease-producing organisms (4,5).
References
Schantz PM. Trichinosis in the United States--1947-1981. Food
Tech 1983;37:83-6.
CDC. Trichinosis surveillance, 1984. MMWR 1986;35:11SS-15SS.
Zimmerman WJ. Evaluation of microwave cooking procedures and
ovens for devitalizing trichinae in pork roasts. J Food Sci
1983;48:856-60, 899.
Zimmerman WJ. An approach to safe microwave cooking of pork
roasts containing Trichinella spiralis. J Food Sci
1983;48:1715-8, 1722.
Zimmerman WJ. Power and cooking time relationships for
devitalization of trichinae in pork roasts cooked in microwave
ovens. J Food Sci 1984;49:824-6.
Disclaimer
All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices. **Questions or messages regarding errors in formatting should be addressed to mmwrq@cdc.gov. Page converted: 08/05/98
|
|
