Molecular diversity of Mycobacterium tuberculosis isolates in Treatment-experienced Patients from Andhra Pradesh, India.

INTRODUCTION: To get a comprehensive idea about the transmission and epidemiology of TB globally and locally, the use of molecular typing methods has become imperative not only for understanding genetic diversity but also the population structure of Mycobacterium tuberculosis complex (MTBC). We aimed to investigate the drug resistance pattern and genetic diversity of MTBC among previously treated patients with sputum smear-positive pulmonary tuberculosis in a South Indian population. METHODOLOGY: 104 patients with sputum smear positivity and who had previously undergone treatment were selected. Drug susceptibility testing, Spoligotyping, MIRU-VNTR, and SNP typing were performed. RESULTS: Mono-resistance to isoniazid 16 (15.38%) was the highest among all drugs. Out of 104 isolates, 24 (23%) isolates were classified as MDR strains. The distributions of most common lineages were: EAI3-Ind-20 (19.23%), EAI5-13 (12.50%), Beijing-12 (11.54%), CAS1-Delhi- 9 (8.65%), and 7 (6.73%) each of T-H37rv, Unknown and Orphan types. MIRU-VNTR-based analysis revealed that there are two major groups: CAS1-Delhi and Beijing groups. Out of 104 isolates, 82 belonged to well-defined lineages and 6 clusters, and the remaining 22 were singletons. SNP analysis showed no mutations associated with five sets of genes in 33 strains. CONCLUSIONS: The occurrence of 11.54% Beijing strains in South India is an important finding. High frequency of Isoniazid mono resistance noticed. Spoligotyping along with MIRU-VNTR and SNP typing is the best approach to the identification of strain lineages. No mutation with Antigen85C gene represents, can be used for vaccine candidates.

HPV genotype prevalence in Indian women with cervical disease and estimation of the potential impact of HPV vaccines on prevention of cervical cancer.

PURPOSE: Human papillomavirus (HPV) causes genital and oropharyngeal cancers worldwide. There are significant gaps exist in the data on HPV genotype prevalence in this part of the country. HPV vaccination is one of the best preventive methods available currently. HPV genotyping plays an important role in the selection of appropriate vaccines and monitoring vaccine efficacy and coverage. The present study aimed to determine the HPV genotype prevalence and to estimate the potential impact of HPV vaccines on invasive cervical cancer. MATERIALS AND METHODS: A total of 204 cervical biopsy samples collected from symptomatic women were subjected to an in-house designed and standardised nested multiplex PCR (NM-PCR) assay. The NM-PCR was designed to detect 38 Mucosal HPV types as a pooled result and genotyping of 15 HPV types. Further, the HPV genotype data was used to estimate the HPV vaccine bivalent, quadrivalent and nonavalent impact on the population using a mathematical formula. RESULTS: Out of 204 samples 188 were subjected to HPV-nested PCR. A total of 163 (86.7%) samples were positive for at least one HPV type. Multiple genotypes were identified in 30% of samples processed. HPV-16 (85.3%) was the most frequently detected genotype followed by HPV-18 (13.5%) and HPV-33 (11.0%). Other genotypes were observed less frequently. Based on the HPV prevalence observed in the study a mathematical model estimated the efficacy of bivalent, quadrivalent and nonavalent vaccines were 76.1%, 76.7%, and 91.1% (average) respectively. CONCLUSIONS: HPV-16 was the most prevalent (>85%) genotype detected in this study. Multiple infections observed in 30% of samples were quite high as compared to the majority of national, and global reference (15-25.4%) data. The Mathematical model showed that a nonavalent vaccine would give better protection.