Post-monsoon waterlogging-associated upsurge of cholera cases in and around Kolkata metropolis, 2015.

The Infectious Diseases and Beliaghata General Hospital, Kolkata, India witnessed a sudden increase in admissions of diarrhoea cases during the first 2 weeks of August 2015 following heavy rainfall. This prompted us to investigate the event. Cases were recruited through hospital-based surveillance along with the collection of socio-demographic characteristics and clinical profile using a structured questionnaire. Stool specimens were tested at bacteriological laboratory of the National Institute of Cholera and Enteric Diseases (NICED), Kolkata. Admission of 3003 diarrhoea cases, clearly indicated occurrence of outbreak in Kolkata municipal area as it was more than two standard deviation of the mean number (911; s.d. = 111) of diarrhoea admissions during the same period in previous 7 years. Out of 164 recruited cases, 25% were under-5 children. Organisms were isolated from 80 (49%) stool specimens. Vibrio cholerae O1 was isolated from 50 patients. Twenty-eight patients had this organism as the sole pathogen. Among 14 infants, five had cholera. All V. cholerae O1 isolates were resistant to nalidixic acid, followed by co-trimoxazole (96%), streptomycin (92%), but sensitive to fluroquinolones. We confirmed the occurrence of a cholera outbreak in Kolkata during August 2015 due to V. cholerae O1 infection, where infants were affected.

Upsurge and spread of G3 rotaviruses in Eastern India (2014-2016): Full genome analyses reveals heterogeneity within Wa-like genomic constellation.

Advent of new strains and shift in predominantly circulating genotypes are characteristics of group- A rotavirus (RVA), one of the major causes of childhood gastroenteritis. During diarrheal disease surveillance at Kolkata, India (2014-2016), a shift in circulating RVA strains from G1P[8] to G3P[8] was seen. Stool samples from children (n = 3048) with acute gastroenteritis were tested of which 38.7% were RVA positive. G1 was the predominant strain (65.3%) in 2014-2015 whereas in late 2015 and 2016, G3 became the preponderant strain (44.6%). In the past decade G3 strains were not observed in this region, we conducted whole genome sequencing of representative strains to gain insight into the phenomenon of emergence and genetic constellation of these circulating human G3 strains. The analyses revealed intergenogroup reassortment in G3P[4] strains (among Wa and DS-1-like genogroup) whereas G3P[8] strains were authentic Wa-like. Phylogenetic analysis revealed Kolkata G3 strains as polymorphic and thus they formed two sub-clusters due to antigenic differences in their VP7 protein. One of the sub-clusters had the wild-type threonine at 87 amino acid position while another sub-cluster had an isoleucine mutation. Presence of additional N-linked glycosylation site at amino acid 283 of VP7 glycoprotein suggests that the major neutralizing epitope on the VP7 (G3) of RotaTeq vaccine differs from the currently circulating G3 strains. The study is important as efficiency of rotavirus vaccine depends on the circulating heterogeneous genotype constellations. Continuous monitoring of circulating RVA strains in endemic settings like India is therefore important in pre- and post-vaccination period to monitor the emergence of new reassortant genotypes in addition to assessing vaccine efficacy.

Perceived morbidity, healthcare-seeking behavior and their determinants in a poor-resource setting: observation from India.

BACKGROUND: To control the double burden of communicable and non-communicable diseases (NCDs), in the developing world, understanding the patterns of morbidity and healthcare-seeking is critical. The objective of this cross-sectional study was to determine the distribution, predictors and inter-relationship of perceived morbidity and related healthcare-seeking behavior in a poor-resource setting. METHODS: Between October 2013 and July 2014, 43999 consenting subjects were recruited from 10107 households in Malda district of West Bengal state in India, through multistage random sampling, using probability proportional-to-size. Information on socio-demographics, behaviors, recent ailments, perceived severity and healthcare-seeking were analyzed in SAS-9.3.2. RESULTS: Recent illnesses were reported by 55.91% (n=24,600) participants. Among diagnosed ailments (n=23,626), 50.92% (n=12,031) were NCDs. Respiratory (17.28%, n=7605)), gastrointestinal (13.48%, n=5929) and musculoskeletal (6.25%, n=2749) problems were predominant. Non-qualified practitioners treated 53.16% (n=13,074) episodes. Older children/adolescents [adjusted odds ratio for private healthcare providers (AORPri)=0.76, 95% confidence interval=0.71-0.83) and for Govt. healthcare provider (AORGovt)=0.80(0.68-0.95)], females [AORGovt=0.80(0.73-0.88)], Muslims [AORPri=0.85(0.69-0.76) and AORGovt=0.92(0.87-0.96)], backward castes [AORGovt=0.93(0.91-0.96)] and rural residents [AORPri=0.82(0.75-0.89) and AORGovt=0.72(0.64-0.81)] had lower odds of visiting qualified practitioners. Apparently less severe NCDs [acid-peptic disorders: AORPri=0.41(0.37-0.46) & AORGovt=0.41(0.37-0.46), osteoarthritis: AORPri=0.72(0.59-0.68) & AORGovt=0.58(0.43-0.78)], gastrointestinal [AORPri=0.28(0.24-0.33) & AORGovt=0.69(0.58-0.81)], respiratory [AORPri=0.35(0.32-0.39) & AORGovt=0.46(0.41-0.52)] and skin infections [AORPri=0.65(0.55-0.77)] were also less often treated by qualified practitioners. Better education [AORPri=1.91(1.65-2.22) for ≥graduation], sanitation [AORPri=1.58(1.42-1.75)] and access to safe water [AORPri=1.33(1.05-1.67)] were associated with healthcare-seeking from qualified private practitioners. Longstanding NCDs [chronic obstructive pulmonary diseases: AORPri=1.80(1.46-2.23), hypertension: AORPri=1.94(1.60-2.36), diabetes: AORPri=4.94(3.55-6.87)] and serious infections [typhoid: AORPri=2.86(2.04-4.03)] were also more commonly treated by qualified private practitioners. Potential limitations included temporal ambiguity, reverse causation, generalizability issues and misclassification. CONCLUSION: In this poor-resource setting with high morbidity, ailments and their perceived severity were important predictors for healthcare-seeking. Interventions to improve awareness and healthcare-seeking among under-privileged and vulnerable population with efforts to improve the knowledge and practice of non-qualified practitioners probably required urgently.