*Excludes cases with unknown or indeterminate menstrual status and cases with unknown month of onset.

TRICHINOSIS — Cases, by year, United States, 1950-1984

In 1984, 68 cases of trichinosis were reported through the MMWR morbidity surveillance system. Written case reports were submitted by 13 states for 65 cases fitting the CDC case definition. Seventy-five percent of the cases occurred in five states: New Jersey reported 17 cases (26%); Texas, 11 (17%); California, eight (12%); Connecticut, seven (11%); and Massachusetts, six (9%). Other reporting states were New York (four), Pennsylvania (four), Alaska (three), Hawaii (one), Maine (one), North Carolina (one), Utah (one), and Virginia (one). The male/female ratio of these 65 cases was essentially equal. The mean age of patients was 34 years, with a range of 3-73. The infective meat item was identified in 60 of the 65 cases. Pork was incriminated in 53 cases (82%), and bear meat in six (9%). Sausage was the most frequently implicated form of pork (43%). In 22 cases, the implicated meat was obtained from a commercial outlet such as a supermarket or butcher shop; in 11 cases, it was obtained directly from the farm; and in seven cases (involving the ingestion of feral swine and bear meat), through hunting. Eight common-source outbreaks were identified, involving a total of 40 cases. Of note was an outbreak among a group of Laotians living in Texas, which involved 12 people. One death was attributed to trichinosis, the first reported since 1981.

'Case data for years subsequent to 1974 are not comparable to those for prior years because of changes in reporting criteria that became effective in 1975.

*Mortality data subsequent to 1978 are not comparable to those for prior years because of changes in classification that became effective in 1979. Late effects of tuberculosis (e.g., bronchiectasis or fibrosis) and pleurisy with effusion (without mention of cause) are no longer included in tuberculosis deaths.

In 1984, 22,255 cases of tuberculosis were reported to CDC, for a rate of 9.4 cases/100,000 population. This represents a 6.7% decrease from the number of reported cases in 1983, and a 7.8% decline in the case rate. From 1968 through 1978, the average annual decrease in the number of tuberculosis cases in the United States was 5.6%. From 1978 through 1981, when there was a large influx of Southeast Asian refugees, the average annual decline was only 1.4%. A 6.8% decrease in the number of cases in 1982, a 6.6% decrease in 1983, and the 6.7% decrease in 1984 indicate that the previous downward trend has resumed. Contributing factors to the decline in 1984 include 1) participation of almost all states in a new national case reporting system, requiring more accurate verification of cases and 2) a decline in the actual number of indigenous cases.

Final mortality data on tuberculosis for 1982 show 1,807 deaths. This is a 6.7% decrease from 1981, when 1,937 deaths were reported. The mortality rate in 1982 was 0.8 deaths/100,000 population.

In 1984, rates for the 50 states ranged from 21.0/100,000 population in Hawaii to 1.0/100,000 population in Wyoming. In general, the southeastern states and the states on the United States-Mexico border reported the highest case rates; rates were generally higher east of the Mississippi.

For all race-sex categories, the case rate was lowest for persons 10-14 years old and was highest for persons 65 years old or older. Rates were highest for males of races other than white, followed by females of races other than white, white males, and white females.

Transmission of tuberculous infection continues to occur, as evidenced by the occurrence of disease among young children. In 1984, 1,236 tuberculosis cases were reported among children under 15 years of age, including 759 cases among children under 5 years of age.