Genetic patterns, sublineages and dynamics of tuberculosis transmission in Cuba, a low burden country

Abstract

AbstractContextIn Cuba, a country with a low incidence of tuberculosis (TB), there is no information on the dynamics of transmission of the disease for two decades.AimsDetermine the genetic patterns and sublineages ofMycobacterium tuberculosiscomplex (MTBC) isolates circulating in 2009 and their relationship with the epidemiological data of the patients.Settings and DesignA retrospective descriptive study was carried out in Cuba with 178 MTBC isolates.Materials and methodsSpoligotyping and mycobacterial interspersed repetitive-unit– variable-number tandem-repeat (MIRU-VNTR) typing with 24 loci were performed. For statistical analysis, non-parametric methods, analysis of variance and homogeneity test, were used.ResultsSpoligotyping produced 39 spoligotypes. The S, Beijing, LAM and Haarlem sublineages prevailed. The clustering rate was 75.84% and the Hunter-Gaston discriminatory index (HGDI): 0.8734. MIRU-VNTR typing with 24-loci defined 154 genetic patterns: six grouped 30 isolates and 148 showed unique patterns. The clustering rate was 14.60% and the HGDI: 0.9926. There was a predominance of sublineages by region: S, Beijing and LAM in the West, Center and East, respectively.ConclusionsThe dynamics of TB transmission in Cuba in 2009 is reported, inferring that this occurs in a limited manner and belonging to risk groups does not favor transmission. It serves to evaluate a megaproject of the Global Fund to reduce the transmission of TB in this country. The population genetic structure of MTBC resembles that of an Ibero-American country, with the exception of the high frequency of the Beijing and S sublineages.