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

Abstract

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