Epidemiology, Genotyping, Mutational and Phylogenetic Analysis of Hepatitis B Virus Infection in North-east India.

BACKGROUND/OBJECTIVE: Hepatitis B virus (HBV) infection is a major public health problem globally. Northeast India is home to indigenous tribes with different ethnicity and high rates of drug abuse and HIV infection. The study was designed to estimate the burden of HBV infection across various spectrums of liver diseases from this region. HBV genotypes and subgenotypes play a role in the chronicity of disease, response to treatment and its progression. As very limited data are available from this region, we tried to elucidate the role of HBV genotypes, HBV mutants and their phylogenetic analysis. METHOD: We designed a prospective multicentric study, and included 7464 liver disease cases, 7432 blood donors and 650 health care workers, who were screened for HBV infection. HBV DNA positive patients were genotyped and subjected to surface protein, precore and core mutation and phylogenetic analysis. RESULTS: The prevalence of HBV infection with respect to different types of liver diseases, blood donors and health care workers was 9.9% (1550/15,546). 49.5% (768/1550) cases were found to be HBV DNA positive. The most common genotype was found to be genotype D 74.2% (570/768), followed by genotype C 6.5% (50/768), A 4.4% (34/768) and I 0.9% (7/768). CONCLUSION: This study highlights the high hepatitis B burden in Northeast India, reflecting lacunae in health care needs of the region. Also, the different genotype distribution and presence of mutations may translate into different rates of liver disease progression, prognosis and ultimately, clinical significance. However, further prospective cohort study from Northeast India is warranted, to elucidate the clinical significance of multiple genotypes and mutation in this unique population.

A Community-Based Study on Functional Disability and Its Associated Factors Among Elderly Individuals in a Rural Setting in Northeastern India.

Background Functional disability in older adults is common and adversely impacts the quality of life. Given the paucity of population-based data, the present analysis attempted to determine the prevalence and factors associated with functional disability in basic activities of daily living (ADLs) among the elderly population in a rural setting of Northeastern state of India Methods A total of 430 elderly were recruited in a population-based cross-sectional study among elderly individuals (≥60 years) during the period 2013-2016 in rural areas of the Dibrugarh district of Northeastern India. The Barthel index was used to measure ADL. Anyone with a Barthel index score <100 (or having limitations in one or more ADL items) were considered as having a functional disability. The analysis of variance (ANOVA) test and the binary logistic regression analysis were used to examine the factors associated with functional disability. Results Overall, 43.7% % (Male 42.9%, Female 44.5%) of the participants had a functional disability. Increasing age, being widowed, having no formal education, being underweight (body mass index (BMI)<18.5 kg/m2), and increasing numbers of morbidities were significantly associated with functional disability among the elderly in this study in age and gender-adjusted logistic regression analysis. Being ≥80 years was associated with a three-fold greater risk (OR=31.72, 95% CI=1.3-6.91) of functional disability than the youngest age group (60-69 years). On the other hand, the presence of more than five morbidities was associated with a nearly 20 times increased risk (OR=19.61, 95% CI=9.01-42.68) than those with zero to two morbidities. Conclusion A high proportion of the rural elderly residents of Dibrugarh had a functional disability. The study provides epidemiological evidence of the risk factors of functional disability in this setting. This epidemiological information may be useful for developing prevention strategies to reduce the burden of functional disability.

Association of processed food, synergistic effect of alcohol and HBV with Hepatocellular Carcinoma in a high incidence region of India.

BACKGROUND: Dietary factors, tobacco, and alcohol use have been identified as important factors of rising various cancer incidence in several northeastern states of India. However, little is known about the factors associated with hepatocellular carcinoma (HCC) in this region. The aim of the paper was to identify the factors associated with HCC in the northeast region. METHODS: A case-control study was conducted in Arunachal Pradesh and Sikkim, two northeastern states of India, including 104 histologically-confirmed cases of HCC and same number (104) of age and sex matched control enrolled. Logistic regression analysis was performed to identify the factors associated with HCC. RESULTS: A statistically significant association was demonstrated between HCC and alcohol consumption, consumption of 'Sai-mod' (OR 2.77, CI 1.57-4.87) a homemade alcohol beverage, and with HBV (OR 7.97, CI 3.36-18.94). Positive synergism index (S = 3.04) was observed between HBV and alcohol consumption to risk of HCC. Higher intake of processed meat (OR 2.56, CI 1.09-6.03) and processed fish (OR 2.24, CI 1.02-4.95) were found associated with increased risk of HCC; and decreased risk of HCC with fresh fish, fruits, and milk. CONCLUSIONS: Strong relationship between different dietary factors, alcohol beverage with HCC suggests that control on dietary and drinking habit will be an important strategy to combat HCC in this region. Risk factors identified in this study will help to plan more effectively targeted risk reduction strategies and programs in this region.

HIV-malaria interactions in North-East India: A prospective cohort study.

BACKGROUND & OBJECTIVES: The interactions between HIV and malaria co-infection have been shown to influence each other in their clinical outcomes in Sub-Saharan Africa. This study was carried out in the two States of north east India endemic for both HIV and malaria infections, to study the interactions between the two diseases in the HIV-infected population. METHODS: In this prospective study, a total of 333 HIV-infected individuals were followed up for a period of 6-18 months in Mizoram and Manipur during 2010-2011. The study assessed the changes in viral load and also the therapeutic efficacy of artesunate plus sulphadoxine-pyrimethamine (AS+SP) combination therapy in HIV-infected and HIV-uninfected individuals with Plasmodium falciparum malaria. RESULTS: Viral load in HIV-infected malaria patients on day zero (D0) ranged from 1110 to 147,000 copies/ml. The log transformation of the geometric means of HIV viral loads revealed no significant difference on different days of follow up. There was 100 per cent adequate clinical and parasitological response (ACPR) after treating with artemisinin based combination therapy (ACT) both in HIV-infected and HIV-uninfected P. falciparum-positive individuals. Similarly, chloroquine showed 100 per cent ACPR in P. vivax HIV-infected individuals. INTERPRETATION & CONCLUSION: The study showed no significant increase in HIV viral load in malaria cases. All HIV-infected and HIV-uninfected P. falciparum malaria-positive cases responded to the treatment with 100 per cent ACPR.

TLR2∆22 (-196-174) significantly increases the risk of breast cancer in females carrying proline allele at codon 72 of TP53 gene: a case-control study from four ethnic groups of North Eastern region of India.

Breast cancer (BC) is the second most common cancer in women. In the North Eastern Region (NER) of India, BC is emerging as an important concern as evidenced by the data available from population and hospital-based cancer registries. Studies on genetic susceptibility to BC are important to understand the increase in the incidence of BC in NER. The present case control study was conducted to investigate the association between tumour suppressor gene TP53 codon 72 polymorphism and innate immune pathway gene TLR2∆22 (-196-174) polymorphism with BC in females of NER of India for the identification of novel biomarker of BC. Four hundred sixty-two histopathologically confirmed BC cases from four states of NER of India, and 770 healthy controls were included by organizing community surveys from the neighbourhood of cases. In our study, no significant association between TP53 codon 72 polymorphisms and the risk of BC was found. However, our study has shown that TP53 codon 72 polymorphism is an important effect modifier. In the present study it was found that females carrying 22 base-pair deletion in the promoter region of their TLR2 gene had two times (AOR= 2.18, 95 % CI 1.13-4.21, p=0.019 in dominant model; AOR= 2.17, 95 % CI 1.09-4.34, p=0.027 in co-dominant model) increased risk of BC whwn they also carry proline allele at codon 72 of their TP53 gene.

Correlation of molecular markers, Pfmdr1-N86Y and Pfcrt-K76T, with in vitro chloroquine resistant Plasmodium falciparum, isolated in the malaria endemic states of Assam and Arunachal Pradesh, Northeast India.

The mechanism of chloroquine (CQ) resistance in Plasmodium falciparum is not clearly understood. However, CQ resistance has been shown to be associated with point mutations in Pfcrt and Pfmdr1. These genes encode for digestive vacuole transmembrane proteins Pfcrt and Pgh1, respectively. The present study was carried out to analyze the association of Pfcrt-K76T and Pfmdr1-N86Y mutations with CQ resistance in Northeast Indian P. falciparum isolates. 115 P. falciparum isolates were subjected to in vitro CQ sensitivity testing and PCR-RFLP analysis for the Pfmdr1-N86Y and Pfcrt-K76T mutations. 100 isolates of P. falciparum were found to be resistant to CQ by the in vitro susceptibility test (geometric mean EC50 2.21 µM/L blood) while 15 were found to be CQ sensitive (geometric mean EC50 0.32 µM/L blood). All the CQ resistant isolates showed the presence of Pfmdr1 and Pfcrt mutations. CQ sensitive isolates were negative for these mutations. Strong linkage disequilibrium was observed between the alleles at these two loci (Pfmdr1-N86Y and Pfcrt-K76T). The results indicate that Pfmdr1-N86Y and Pfcrt-K76T mutations can be used as molecular markers to identify CQ resistance in P. falciparum. The result necessitates the evaluation of CQ in vivo therapeutic efficacy in endemic areas for more effective malaria control strategies.

GSTM1 and GSTT1 polymorphism and susceptibility to esophageal cancer in high- and low-risk regions of India.

Glutathione transferases, a super family of dimeric phase II metabolic enzymes play a vital role in biotransformation of many substances. This study evaluates the influence of genetic polymorphism of GSTM1 and GSTT1 gene loci on esophageal cancer risk in Assam and Delhi from India. DNA from blood samples of esophageal cancer cases (203,112) and controls (286,150) from Assam and Delhi, respectively, were extracted. GSTM1 and GSTT1 polymorphisms were analyzed by multiplex PCR procedure. Differences in proportions were tested using Pearson's chi-square test with odds ratio (OR) and 95 % confidence interval (CI). Risk of esophageal cancer was approximately twice in individuals having homozygous GSTM1 (OR-2.1, 95 % CI, 1.44-3.13) and GSTT1 null genotypes (OR-1.7,95 % CI, 0.99-2.77) in Assam, and around three times in GSTT1 null genotype (OR-2.9, 95 % CI, 1.56-5.27) in Delhi population. GSTM1 null genotype seems to play a protective role (OR-0.7, 95 % CI, 0.39-1.27) in Delhi. A significant association of GSTM1 null genotype with esophageal cancer was observed in a younger age group in Assam (OR-2.7, 95 % CI, 1.48-5.01), and in Delhi population association was observed in smokers with GSTT1 null genotype (OR-2.5, 95 % CI, 1.04-6.07), and alcoholics having GSTM1 null genotype (OR-2.6, 95 % CI, 0.99-6.77). Significant association of GSTM1 null genotype in Assam was observed between cancer cases and controls in fermented betel nut chewers only (OR-2.8, 95 % CI, 1.19-6.72), whereas, smoking and alcohol failed to show any correlation with GSTM1/GSTT1 genotypes. Cancer development is not only due to exogenous or endogenous carcinogens but depends on their interaction with genes that are involved in the detoxification of these carcinogens.

Measurement of cholesterol and triglycerides from a dried blood spot in an Indian Council of Medical Research-World Health Organization multicentric survey on risk factors for noncommunicable diseases in India.

BACKGROUND: Dried blood may be a convenient method of sample collection in epidemiological studies; however, the method needs evaluation in a field settings. In the present study, feasibility of using dried blood for measurement of cholesterol and triglycerides was evaluated in multicenter surveillance study for noncommunicable disease (NCD). METHODS: Samples were collected in a cross-sectional study for NCD risk factor surveillance conducted in six centers in India. For every tenth subject recruited, a blood sample was also collected on filter paper. These 10% serum samples and dried blood spots were analyzed for cholesterol and triglycerides. RESULTS: The mean coefficient of variation (CV) for cholesterol was less than 10% between dried blood and serum in five of the six participating centers. Only one center showed a high CV of 14%. Similarly, the mean bias was less than 10% in five centers. The intraclass correlation between cholesterol values in dried blood and serum were greater than 0.638 in all centers, which suggests a good homogeneity of results. The mean CV for triglycerides ranged from 0.36% to 17.97%. The intraclass correlation between triglyceride values in dried blood and serum ranged from 0.756 to 0.880 in the six centers. CONCLUSION: In conclusion, dried blood would be a good method for collection of blood for measurement of cholesterol and triglycerides for population health surveys. However, the benefits of blood spot analysis should be weighed against potential sources of errors attributable to sampling and other factors, such as temperature and humidity, in a country like India.

Studies on the breeding habitats of the vector mosquito Anopheles baimai and its relationship to malaria incidence in Northeastern region of India. Breeding habitats of Anopheles baimai and its role in incidence of malaria in Northeastern region of India.

Entomological survey was conducted to know the breeding habitat preference of the forest breeder malaria vector Anopheles baimaii, known earlier as An. dirus species D in the northeastern region of India. Breeding potential of the vector in forest areas was found to be high in water stored in jungle pool (69.84%) followed by elephant footprints with clear water (39.13%) and with turbid water (26.19%), whereas in forest fringe areas, the vector breeding was more prominent in elephant footprints: 65.11% in clear water and 62.5% in turbid water. Although other habitats had shown only low breeding of the vector, all types of habitats were positively correlated with malaria occurrence. Cattle hoof marks (r = 0.998) and elephant footprint (turbid; r = 0.999) explained nearly the same amount of variance. It was observed that deforestation as well as elephant habitat-type destruction had engendered man-elephant conflicts intensively in fringe areas. Seasonal abundance pattern of this vector was found to vary in forest and forest fringe areas in relation to different habitats. Seasonal abundance of An. baimaii was significantly different in different habitats. The Tukey post hoc comparisons indicated that the abundance of An. baimaii in different habitats was significantly higher (P < 0.05) in monsoon season than that of premonsoon and postmonsoon seasons. No significant difference was observed between premonsoon and postmonsoon seasons. The findings therefore will eventually help to predict transmission of malaria in targeted area and in formulating an improved malaria control program in the northeastern region of India.