Prisons throughout the world represent a situation where risk factors for acquiring tuberculosis (TB) are common and require special attention for TB control and prevention. After recognizing four extra pulmonary TB cases among prisoners hospitalized in a Jeddah hospital, we learned of 40 prisoners hospitalized for pulmonary TB and began an epidemiological investigation to determine the reasons for the large number of cases.
Methodology
We defined a pulmonary TB case as an inmate of Jeddah prison who developed a cough with a sputum smear positive for acid fast bacilli and extra pulmonary TB as an illness with TB granuloma demonstrated by histology from July 1993 to March 1995. To find cases, we reviewed records of the prison clinic, the two hospitals used by the prison, and the Jeddah TB control center. We compared cases in prisoners to control prisoners selected at random from all prisoners. We screened 315 prisoners with chest films and sputum to find undetected cases.
Results
From July 1993 to February 1995, 53 cases of pulmonary (49 cases) and extra pulmonary TB (4 cases) were diagnosed among prisoners (incidence rate = 45.6 per 10,000 per year). The time between admission to the prison and onset of symptoms ranged from 0 to 1162 days (median 216) and 87% of prisoners had onset after one or more months in the prison. Referral from the clinic for TB diagnosis was delayed from 31 to 65 days (mean 54) after onset of cough. The risk of TB increased with crowding (Chi square for trend = 5.1, p<0.05) and time spent in prison (p<0.01, ANOVA). Prisoners with diabetes mellitus (odds ratio [OR] = 16.95% confidence interval [CI]=7.7-32) and smokers (OR=2.4,95% CI=53-11) had a greater risk of TB. Through screening 315 prisoners, we detected 28 previously undetected TB cases (889 per 10,000). The rate of tuberculin positively increased with the length of time prisoners spent incarcerated.
Conclusion
The TB problem in this prison was related to delayed medical attention, delayed and missed TB diagnosis, crowding, and personal risk factors. Since prison conditions and prisoner characteristics are not easily changed, medical services in the prison must improve to enable prompt detection of new TB cases and to evaluate the incoming and released prisoners.