Proportion Of Tuberculosis Cases Research Articles

Tuberculosis among refugees and displaced people at the Burundi-Rwanda border.

On the basis of reports from urban centers [1, 2], HIV infection is considered the major factor responsible for the increased rate of tuberculosis (TB) in sub-Saharan Africa [3]. In the Hospital of Kiremba in Burundi, 10 km from the Burundi-Rwanda border, we surveyed TB morbidity from 1992 to 1995. To test the possible influence of the ethnicity-related fighting begun in late 1993 [4] on the spread of TB, we retrospectively divided the study period into two subperiods (1992‐1993 and 1994‐1995). For all patients with current or recent histories of fever, cough, and bloody sputum and all patients with symptoms of lower respiratory tract infection (LRTI) who had failed to respond to antibiotics, Ziehl-Neelsen staining of sputum specimens for acid-fast bacilli (AFB) was undertaken. Serology for antibodies to HIV was performed by use of ELISA. The hospital patient population consisted of local rural residents and patients from urban centers of Burundi, and, since early 1994, numerous Rwandan refugees from a nearby camp [4]. Hospital admissions declined from 8,050 in 1992‐1993 to 3,112 in 1994‐1995, whereas microbiologically proven pulmonary TB cases (AFB positive) rose from 148 to 167, an increase from 1.8% to 5.4% (P o .0001). The number of patients requiring AFB testing decreased; however, the percentage increased from 24.3% during 1992‐1993 to 37.6% in 1994‐1995 (P o .0001). The AFB positivity rates were comparable during the first 3 years of the study (7.1%, 8.0%, and 9.5%), but in 1995 these values almost doubled (16.9%; P o .0001). TB associated with HIV infection accounted for 20% of the TB cases from 1992 to 1993, but this percentage decreased to 6% in 1995 (PA .007). On the basis of the proportion of TB cases per total hospital admissions and on the AFB positivity rate in 1992‐1993, we found Figure 1. Representation of the geographical area of the Hospital 107 excess TB cases in 1994‐1995. Rwandan refugees contributed of Kiremba together with a map of Burundi. Large arrows indicate significantly to this increase (58 cases, 54.2%), but 47 of the re- the major flows of demographic movement across the border. maining 49 excess cases occurred among local rural residents. A Burundi-Rwanda border; A urban centers; HA Hospital Thirty of these 47 cases involved the inhabitants of a single zone, of Kiremba; R A refugee camp. the hill of Marangara; this group accounted for nearly 20% of hospital attendance in both subperiods, but the percentage of TB cases among these residents rose from 2% in 1992‐1993 to 7.2% since 1994), which preceded the subsequent major increase in the

Tuberculosis screening for immigrants and refugees. Diagnostic outcomes in the state of Hawaii.

The effectiveness of the required overseas tuberculosis (TB) screening for immigrants and refugees to the United States has not been evaluated since new guidelines were introduced in 1991. Using data from the Hawaii State TB register for 1992-1993, patient records, and data from the U.S. government notifications of suspect TB among aliens, we determined the percentage of persons either classified as having active TB (B1), inactive TB (B2), or considered "normal" overseas, who were evaluated and subsequently diagnosed with active TB within 1 yr of arrival in the United States. Of the 124 TB cases among immigrants and refugees evaluated within 1 yr of arrival, 78 (63%) had been classified overseas as B1, 17 (14%) as B2, and 29 (23%) as "normal." The proportion of TB cases diagnosed after arrival in the United States was 14.0% for B1s and 2.1% for B2s. This proportion decreased with increasing age. A positive skin test was a strong predictor (OR: 10.7; 95% CI: 1.4-80.1) of culture-confirmed TB. These data document that immigrants and refugees with B1 and B2 TB status have a high prevalence of active TB. They should be promptly evaluated after arrival in the United States to determine the need for curative or preventive therapy.

The proportion of tuberculosis cases in Tanzania attributable to human immunodeficiency virus.

Routine data obtained from the National Tuberculosis and Leprosy Programme (NTLP) of Tanzania have shown a constant increase in the notified number of tuberculosis (TB) cases since 1982. Possible causes include an improved reporting system, improvement in health services after the introduction of short course chemotherapy (SCC), and human immunodeficiency virus (HIV) infection. This paper examines to what extent the increased TB case detection rate can be attributed to HIV infection, by calculating the population attributable risk for various years. The prevalence of HIV infection was obtained from data of the National AIDS Control Programme and the relative risk of HIV for developing TB from a case-control study and the literature. Between 1985 and 1989 the increase was the highest among women aged 15-24 years and men aged 25-34 years; age groups in which HIV prevalence is highest. In the case-control study HIV prevalence among blood donors was 9.4% and among smear-positive pulmonary TB patients 51.6%, giving an odds ratio (OR) of 8.1 (95% confidence interval (CI): 4.4-16.3). For all TB cases the OR was 11.8. In a population with an HIV prevalence of 10%, about 40% of the smear-positive TB patients are attributable to HIV. The excess of TB cases in the entire country between 1982 and 1989 can be attributable to HIV infection. This has implications for TB control and socioeconomic consequences in the country.

Human T-cell lymphotropic virus-III (HTLV-III) seropositivity and related disease among 71 consecutive patients in whom tuberculosis was diagnosed. A prospective study.

The incidence of tuberculosis has recently risen in Southeast Florida. In order to determine the number and proportion of tuberculosis cases and the characteristics of tuberculosis that might be related to human T-cell lymphotrophic virus-III (HTLV-III) infection, all patients seen by the Dade County Florida Public Health Department-Tuberculosis Clinic during a 6-month period were medically evaluated and screened for HTLV-III antibody by an enzyme-linked immunosorbent assay. Of 71 consecutive patients confirmed to have tuberculosis (70 by culture) during the study period, 22 (31%) were seropositive and 49 (69%) were seronegative for HTLV-III antibody. The seropositive group had a significantly higher proportion of patients who were black, Haitian, and within the age group of 25 to 44 yr. The seropositive group also had a significantly higher rate of mild-to-moderate serum aspartate transaminase elevations (less than or equal to 5 times normal), tuberculin skin test false negativity, extrapulmonary tuberculosis (especially lymphatic), and pulmonary tuberculosis with an atypical radiographic picture. The seropositive group had a significantly lower proportion of patients with sputum cultures positive for M. tuberculosis. There was no significant difference between the groups with respect to the proportion of patients with positive sputum smears when sputum cultures were positive, serious antituberculosis drug reactions (requiring discontinuation of therapy), or percent of home contacts who were tuberculin skin tested and found to be positive. At the time of the diagnosis of tuberculosis, only 6 (27%) of the seropositive patients with tuberculosis had clinical evidence of AIDS or AIDS-related complex (unexplained thrush).(ABSTRACT TRUNCATED AT 250 WORDS)