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ABSTRACTA preliminary investigation of the genetic biodiversity of Mycobacterium tuberculosiscomplex strains in Cameroon, a country with a high prevalence of tuberculosis, described a group of closely related M. tuberculosisstrains (the Cameroon family) currently responsible for more than 40% of smear-positive pulmonary tuberculosis cases. Here, we used various molecular methods to study the genetic characteristics of this family of strains. Cameroon family M. tuberculosisstrains (i) are part of the major genetic group 2 and lack the TbD1 region like other families of epidemic strains, (ii) lack spacers 23, 24, and 25 in their direct repeat (DR) region, (iii) have an identical number of repeats in 8 of 12 variable-number tandem repeats of mycobacterial interspersed repetitive unit (MIRU-VNTR) loci, (iv) have similar IS6110-restriction fragment length polymorphism (RFLP) multiband patterns (10 to 15 copies) with seven common IS6110bands, (v) do not have an IS6110element in their DR locus, and (vi) have four IS6110elements in open reading frames (adenylate cyclase, phospholipase C, moeY, and ATP binding genes). Analysis by spoligotyping, MIRU-VNTR, and IS6110-RFLP typing methods revealed differences not observed in previous studies; polymorphism as assessed by MIRU-VNTR typing was lower than suggested by spoligotyping, and in rare cases, strains with identical IS6110-RFLP patterns had spoligotypes differing by as much as 15 spacers. Our findings confirm the recent expansion of this family in Cameroon and indicate that the interpretation of molecular typing results has to be adapted to the characteristics of the strain population within each setting. The knowledge of this particular genotype, with its large involvement in tuberculosis in Cameroon, allows greater refinement of tuberculosis transmission studies by interpreting data in the context of this geographic area.

ABSTRACTThe prevalence of Chlamydia trachomatisinfection was 3.78% out of 1,277 volunteer students screened by direct fluorescence assay and Cobas Amplicor PCR. The infection was associated with the nonuse or inconsistent use of condoms in women (P= 0.026) and a previous sexually transmitted infection in men (P= 0.023). The most frequent genotypes determined by sequencing the omp1genes of 25 clinical isolates were E (44%) and F (20%), and some strains harbored mutations, but E genotype strains did not.

ABSTRACTWe analyzed DNA polymorphisms in 455 Mycobacterium tuberculosiscomplex isolates from 455 patients to evaluate the biodiversity of tubercle bacilli in Ouest province, Cameroon. The phenotypic and genotypic identification methods gave concordant results for 99.5% of M. tuberculosisisolates (413 strains) and for 90% of Mycobacterium africanumisolates (41 strains). Mycobacterium boviswas isolated from only one patient. Analysis of regions of difference (RD4, RD9, and RD10) proved to be an accurate and rapid method of distinguishing between unusual members of the M. tuberculosiscomplex. Whereas M. africanumstrains were the etiologic agent of tuberculosis in 56% of cases 3 decades ago, our results showed that these strains now account for just 9% of cases of tuberculosis. We identified a group of closely genetically related M. tuberculosisstrains that are currently responsible for >40% of smear-positive pulmonary tuberculosis cases in this region of Cameroon. These strains shared a spoligotype lacking spacers 23, 24, and 25 and had highly related IS6110ligation-mediated (LM) PCR patterns. They were designated the “Cameroon family.” We did not find any significant association between tuberculosis-causing species or strain families and patient characteristics (sex, age, and human immunodeficiency virus status). A comparison of the spoligotypes of the Cameroon strains with an international spoligotype database (SpolDB3) containing 11,708 patterns from >90 countries, showed that the predominant spoligotype in Cameroon was limited to West African countries (Benin, Senegal, and Ivory Coast) and to the Caribbean area.