Molecular characterization of Vibrio cholerae O1 strains circulating in Assam: a north eastern state of India.

BACKGROUND AND OBJECTIVES: Information on the genetic epidemiology of cholera in Assam, a northeastern state of India is lacking despite cholera being a major public health problem. The study aimed to determine the virulence genes and genes encoding antibiotic resistance in Vibrio cholerae isolates and to determine the prevalent genotypes based on the presence or absence of the virulence genes and ctxB genotype. MATERIALS AND METHODS: Twenty-five V. cholerae strains were subjected to conventional biotyping and serotyping followed by multiplex PCR to detect ctxA, ctxB, zot, ace, O1rfb, tcpA, ompU, ompW, rtxC, hly and toxR and antibiotic resistance genes. Cholera toxin B (ctxB) gene was amplified followed by sequencing. RESULTS: All the V. cholerae O1 isolates were El Tor Ogawa and showed the presence of the core toxin region representing the genome of the filamentous bacteriophage CTXø. The complete cassette of virulence genes was seen in 48% of the isolates which was the predominant genotype. All the isolates possessed amino acid sequences identical to the El Tor ctxB subunit of genotype 3. sulII gene was detected in 68% of the isolates, dfrA1 in 88%, strB in 48% and SXT gene was detected in 36% of the isolates. CONCLUSION: Toxigenic V. cholerae O1 El Tor Ogawa strains of ctxB genotype 3 carrying a large pool of virulence genes are prevailing in Assam. Presence of a transmissible genetic element SXT in 36% of the strains is of major concern as it indicates the emergence of multiple drug resistance among the V. cholerae isolates.

Co-circulation of different genotype, sub-genotype and serotypes of hepatitis B virus (HBV) and its epidemiology in Assam: A north-eastern state of India.

PURPOSE: Hepatitis B virus (HBV) infection is a global health problem. HBV has different genotypes and subgenotypes with geographical distinctiveness. AIMS: To study the molecular epidemiology and distribution pattern of HBV in Assam; a distinct state of India that may have different genotypic divergence. SETTINGS AND DESIGN: Patients attending a tertiary care hospital susceptive of Hepatitis B were included, irrespective of age and sex in different agro-climatic zones of Assam. METHODS: Samples positive for Hepatitis B surface antigen test and COBAS®TaqMan® HBV tests were further confirmed by PCR and sequencing followed by phylogenetic analysis. STATISTICAL ANALYSIS USED: Chi-square test was used to determine whether there was a significant difference among the results in this study. RESULTS: An increase trend of HBV positive cases has been observed in the state. The incidence in female was lower than that of male and age group 26-35 years was most vulnerable. Genotype D, subgenotype D2 and serotype ayw3 were predominant genotype, subgenotype and serotype. The prevalence of subgenotype C3 was a new finding. Phylogenetic analysis showed that the genotypes of HBV prevailing in the state have close relationship with neighboring countries of India which may be due to increased cross border migration of population CONCLUSIONS: This comprehensive study of HBV in Assam described the distribution of HBV genotypes and subgenotypes and serotypes in different agro-climatic zones of Assam. These findings will help to formulate the roadmap for prevention and control of the disease as well as targeted therapy of HBV in this State.

Molecular characterization of influenza A(H1N1)pdm09 viruses circulating at various geographical locations in India, 2017.

Background & objectives: Influenza virological surveillance is an essential tool for the early detection of novel genetic variants of epidemiologic and clinical significance. This study was aimed to genetically characterize A(H1N1)pdm09 virus circulating in 2017 and to compare it with the global data. Methods: The regional/State Viral Research and Diagnostic Laboratories (VRDLs) provided influenza diagnosis for referred clinical samples and shared influenza A(H1N1)pdm09 positives with the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV), Pune, India, for hemagglutinin (HA) gene phylogenetic analysis. Sites at Manipal, Jaipur and Dibrugarh performed the sequencing and shared the sequence data for analysis. The antiviral susceptibility of influenza viruses was assessed for known molecular marker H275Y at the ICMR-NIV, Pune. Results: All the eight VRDLs had well-established influenza diagnostic facilities and showed increased activity of influenza A(H1N1)pdm09 during 2017. Phylogenetic analysis showed that the viruses from the different regions of the country were similar to A/Michigan/45/2015 strain which was the 2017-2018 recommended vaccine strain and were clustered with the globally circulating clade 6B.1 with signature mutations S84N, S162N and I216T. The clade 6B.1 showed further subgrouping with additional mutations S74R, S164T and I295V; however, there was no significant association between the presence of these mutations and severity of disease due to influenza. All the study viruses were sensitive to oseltamivir. Interpretation & conclusions: During the study period, all the study sites reported globally circulating A/Michigan/45/2015 vaccine strain of influenza A(H1N1)pdm09 viruses and remained sensitive to oseltamivir. Further genetic and antigenic characterization of influenza viruses is recommended to address public health concerns.

Clinicomycological profile of pityriasis versicolor in Assam.

BACKGROUND: Geographical variation in the distribution of Malassezia species associated with pityriasis versicolor (PV) has led to the necessity of studying epidemiological, mycological, and clinical characteristics of PV. AIMS: To study the epidemiological, mycological, and clinical characteristics of PV in a tertiary care hospital. SETTINGS AND DESIGN: The study was carried out with a cross-sectional design. MATERIALS AND METHODS: Two hundred and sixty-two consecutive PV patients were subjected to detailed history, clinical examination, and investigations. Skin scrapings were processed by direct microscopy and culture. Isolates were identified by phenotypic characteristics and polymerase chain reaction-restriction fragment length polymorphism. Association of Malassezia species with clinical and epidemiological characteristics was studied. Statistical analysis of the data was done using statistical software. RESULTS: Maximum number of PV cases (33.9%) belonged to the age group of 21-30 years with a male preponderance. 61.4% of the patients had a sedentary lifestyle, 70.2% showed the gradual onset of the disease, 51.1% presented with pruritus and in 66.4% of the patients symptoms were continuous. Most commonly involved body site was neck (27.8%), 77.09% of the lesions were bilaterally asymmetrical, 87.4% were macular, and 89.3% were hypopigmented. Malassezia furfur (77.3%) was the predominant species. Sedentary lifestyle (61.4%) and increased sweating (48%) were the most commonly associated predisposing factors. CONCLUSION: PV is more common in males. Distribution of Malassezia species varies significantly from those reported in other parts of India. M. furfur was the most common species responsible for PV in our region. Hence, further studies are required to evaluate the exact cause of this variation.