Significance of the tuberculin test in the elderly.

Nine hundred thirty-three persons over 65 years of age, residing in long-term or extended-care facilities in Vancouver, Canada, had tuberculin tests. In addition to PPD-tuberculin, 5 TU and 250 TU, we used PPD-Battey, Candida albicans, mumps, and Trichophyton antigens. Twenty-five percent reacted to 5 TU of tuberculin with reactions of 10 mm or more.

Plicatic acid-specific IgE and nonspecific bronchial hyperresponsiveness in western red-cedar workers.

In a cross-sectional survey of 652 workers in a western red-cedar sawmill, we obtained data on symptoms, pulmonary function, immediate skin reactivity to common allergens, nonspecific bronchial responsiveness, total IgE level, and sensitization to plicatic acid conjugated with human serum albumin as measured by RAST. Dust exposure was estimated by personal and area sampling for total dust during a work shift and cumulative exposure by duration of employment. Seven percent of the workers had an elevated RAST, and 20% had nonspecific bronchial hyperresponsiveness.

Host factors affecting longitudinal decline in lung spirometry among grain elevator workers.

The host factors affecting the longitudinal decline in lung function among 267 white male grain elevator workers who were still working in the industry and did not change their smoking habits over a period of six years were studied. Spirometric measures declined more rapidly in older grain handlers as compared with younger workers. Smokers had slightly greater decline in spirometry compared to nonsmokers, but the differences failed to reach the level of statistical significance.

Ten year evaluation of a trial of chemoprophylaxis against tuberculosis in Frobisher Bay, Canada.

A trial of chemoprophylaxis to prevent tuberculosis in Canadian Inuit (Eskimos) was carried out in Frobisher Bay, Canada during 1971-1974. A completely supervised regimen of isoniazid and ethambutol thrice weekly for 18 months was administered. A 10-year evaluation of 370 treated persons and 217 control subjects demonstrates the sustained value of adequate chemoprophylaxis in reducing the risk of developing active tuberculosis in the 3 groups under study--1, those with a previous episode of active tuberculosis, 2, positive tuberculin reactors with normal chest X-ray and 3, BCG vaccinated individuals with large tuberculin reactions.

Tuberculosis in Inuit.

Tuberculous infection was first introduced to the majority of the Inuit (Eskimos) in the first half of this century. In the 1950s tuberculosis became a grave problem with the mortality rate approaching 1% per annum and the incident rate almost 3%. The annual risk of infection has been estimated at 25% per annum.