Infectiousness Of Tuberculosis Research Articles

Living in the Shadow of Death: Tuberculosis and the Social Experience of Illness in American History

Now that tuberculosis is returning with a new vengeance, public and professionals alike have a heightened interest in this fascinating disease. Tuberculosis has plagued mankind since Paleolithic (Old Stone Age) period. It was present mostly in animals, with only sporadic human infections. The domestication of cattle in 18th century would crowd them together, and fact that people commonly lived above animal quarters to benefit from heat led to 18th-century epidemics in Europe. A human mutant variant can be traced to that time. Tuberculosis was dubbed the captain of all these men of death by John Bunyan in 1680. It was another 200 years before knowledge of infectiousness of tuberculosis was established by momentous demonstration by Robert Koch in 1882 that it was a bacterial infection. In prebacteriologic era, tuberculosis had been considered an inheritable disease, since it was found in many family

The effect of human immunodeficiency virus type-1 on the infectiousness of tuberculosis

Setting: Developing country tertiary referral hospital plus catchment community. Objective: To determine the infectiousness of culture-confirmed pulmonary tuberculosis in patients infected with Human Immunodeficiency Virus type-1 (HIV-1). Design: Comparison of the incidence of tuberculosis and the prevalence of tuberculin skin test positivity among the household contacts of both HIV-1 positive and negative cases with pulmonary tuberculosis. Results: Of 255 contacts of HIV-1 negative index cases, 2 were HIV-1 positive and of 102 contacts of HIV-1 positive index cases, 14 were HIV-1 positive (odds ratio (OR) = 20.0 95% Confidence Interval (CI) 4.4−193). 21 cases of tuberculosis were diagnosed among contacts, of whom 3 were HIV-1 positive. The overall unadjusted OR for tuberculosis among contacts of HIV-1 positive index cases was 1.6 (95% CI 0.6−4.3) compared to contacts of HIV-1 negative index cases. Amongst HIV-1 negative contacts alone the OR was 1.5 (95% CI 0.4−4.4). In this group the best predictors of tuberculosis among contacts were female sex of the index case (OR = 3.4 95% CI 1.1−12), sharing the same bed as the index case (OR = 2.6 95% CI 0.9−7.4), and contact's age less than 5 years (OR = 3.3 95% CI 1.1−9.5). HIV-1 positive contacts were more likely to develop tuberculosis than HIV-1 negative contacts (OR = 4.1 95% CI 0.7−17). Tuberculin skin test positivity rates were the same among the HIV-1 negative contacts of HIV-1 positive and negative index cases (OR = 1.1 CI 0.7−1.6). Conclusions: HIV-1 associated pulmonary tuberculosis is not more infectious than tuberculosis alone. The presence of HIV-1 in a community does not mandate a change in the management of contacts of patients with pulmonary tuberculosis.

The impact of HIV on infectiousness of pulmonary tuberculosis: a community study in Zambia.

To examine the impact of HIV on infectiousness of pulmonary tuberculosis (TB). A cross-sectional tuberculin survey carried out among household contacts of HIV-1-positive and negative patients with bacteriologically confirmed pulmonary TB. Contacts were also examined for active TB. Index cases were recruited from patients attending the University Teaching Hospital in Lusaka, Zambia and household contacts were examined during visits to their homes within Lusaka. A total of 207 contacts of 43 HIV-positive patients, and 141 contacts of 28 HIV-negative patients with pulmonary TB were examined. Proportion of contacts of HIV-positive and negative index cases with a positive tuberculin response (diameter of induration > or = 5 mm to a dose of 2 tuberculin units). Fifty-two per cent of contacts of HIV-positive pulmonary TB patients had a positive tuberculin response compared with 71% of contacts of HIV-negative patients (odds ratio, 0.43; 95% CI, 0.26-0.72; P < 0.001). This difference persisted after allowing for between-household variations in the tuberculin response. Tuberculin response in the contact was related to age of contact, intimacy with the index case and crowding in the household. However, the effect of HIV status of the index case was not confounded by these variables. Tuberculin response in the contact was also related to the number of bacilli seen in the sputum smear of the index case which partially explained the effect of HIV status of the index case. Active TB was diagnosed in 4% of contacts of HIV-positive and 3% of contacts of HIV-negative cases, respectively (P = 0.8). HIV-positive patients with pulmonary TB may be less infectious than their HIV-negative counterparts and this may partly be explained by lower bacillary load in the sputum.

Editorial: Effect of chemotherapy on infectiousness of tuberculosis.

Today, tuberculous patients are being treated widely in general hospitals and at home rather than being isolated from society in special sanatoriums. Often, they are discharged from the hospital while tubercle bacilli can still be easily identified in their sputum. This practice has generated considerable concern in some quarters that tuberculosis might thereby be transmitted to unsuspecting persons. An understanding of the transmission of tuberculosis among human beings was slow to evolve, and practices were based largely on fallacious conclusions derived from studies of the problem among nursing and medical students from 1920 to 1940.1 It appeared that tuberculosis must . . .