The first population-based national tuberculosis prevalence survey in Ethiopia, 2010-2011.

SETTING: Tuberculosis (TB) remains a major public health problem in Ethiopia. OBJECTIVE: To determine the prevalence of pulmonary TB among the general adult population aged ≥15 years in 2010-2011. METHOD A nationwide, cluster-sampled, stratified (urban/rural/pastoralist), cross-sectional survey was conducted in 85 selected clusters. All consenting participants were screened for TB using: 1) chest X-ray (CXR) and 2) an interview to screen for symptoms suggestive of TB disease. RESULT: Of 51,667 eligible individuals, 46,697 (90%) participated in the survey and completed at least the screening interview. CXR was performed among 46,548 (99.7%) participants. A total of 6080 (13%) participants were eligible for sputum examination. From the survey, it was estimated that in the national adult population 1) the prevalence of smear-positive TB was 108/100,000 (95%CI 73-143), and 2) that of bacteriologically confirmed TB was 277/100,000 (95%CI 208-347). CONCLUSION: We found that the TB burden was lower than previously thought, which may indicate better programme performance. However, a high proportion of TB among young persons suggests that TB is circulating in the community and that there is a need for more efforts to limit the spread of TB disease.

Phenotypic and genotypic analysis of multidrug-resistant tuberculosis in Ethiopia.

SETTING: National Tuberculosis Reference Laboratory, Addis Ababa, Ethiopia. OBJECTIVES: To determine the drug susceptibility pattern of Mycobacterium tuberculosis isolates and to genetically characterise multidrug-resistant tuberculosis (MDR-TB) isolates. DESIGN: A total of 107 M. tuberculosis isolates recovered during the period December 2005-August 2006 were tested for drug susceptibility against streptomycin, isoniazid, rifampicin and ethambutol (SHRE) using the proportion method on Löwenstein-Jensen medium. The MDR-TB isolates were tested against kanamycin, ciprofloxacin, capreomycin, D-cycloserine and ethionamide. Genotyping was performed using spoligotyping. RESULTS: MDR-TB was observed in one of the 44 new cases (2.3%) and 45/63 previously treated patients (71.4%). Drug susceptibility testing against second-line drugs (SLDs) showed that 26.1% of all MDR-TB isolates were susceptible to all SLDs tested and 73.9% were resistant to one or more classes of SLD. Extensively drug-resistant (XDR) TB was detected in two isolates (4.4%). T3_ETH was the predominant spoligotype, followed by CAS_KILI. In this African setting, no Beijing spoligotype was identified. CONCLUSION: Both MDR- and XDR-TB are present in Ethiopian patients. MDR-TB was found to be associated with T3 and Central Asian genotypes.

HIV-1 subtype C syncytium- and non-syncytium-inducing phenotypes and coreceptor usage among Ethiopian patients with AIDS.

OBJECTIVE: To assess syncytium-inducing (SI) and non-syncytium-inducing (NSI) frequencies, coreceptor usage and gp120 V3 sequences of HIV-1 isolates from Ethiopian AIDS patients. PATIENTS: Cross-sectional study on 48 hospitalized AIDS patients (CD4 T cells < 200 x 10(6) cell/l) with stage III or IV of the WHO staging system for HIV-1 infection and disease. METHODS: Peripheral blood mononuclear cells (PBMC) from all 48 patients were tested by MT-2 assay to determine SI/NSI phenotypes. Lymphocyte subsets were enumerated using Coulter counting and FACScan analysis. Viral load determination used a nucleic acid sequence-based amplification assay (NASBA). Coreceptor usage of HIV-1 biological clones was measured using U87 CD4/chemokine receptor transfectants and phytohemagglutinin-stimulated PBMC of healthy donors with wild-type CCR5 and homozygous mutation CCR5delta32 (a 32 base-pair deletion in CCR5). Reverse transcriptase polymerase chain reaction sequencing was performed on the third variable region (V3) of the HIV-1 gene gp120. Sequence alignments were done manually; phylogenetic analyses used PHYLIP software packages. RESULTS: SI viruses were detected for 3/48 (6%) AIDS patients only. Lower mean absolute CD4 counts were determined in patients with SI virus compared with NSI (P = 0.04), but no differences in viral load were observed. All patients were found to be infected with HIV-1 subtype C, based on V3 sequencing. NSI biological clones used CCR5 as coreceptor; SI biological clones used CXCR4 and/or CCR5 and/or CCR3. CONCLUSIONS: Ethiopian patients with HIV-1 C-subtype AIDS harbour a remarkably low frequency of SI phenotype viruses. Coreceptor usage of these viruses correlates with their biological phenotypes.