Assessment of effectiveness of Japanese encephalitis vaccination in West Bengal, India using sample positivity rate as an alternate measure.

BACKGROUND & OBJECTIVES: Japanese encephalitis (JE), is a vaccine preventable mosquito borne arboviral disease. The State Health Department of West Bengal, India started a vaccination programme using live attenuated, single dose JE vaccine (SA-14-14-2) in children aged 1-below15 years since 2006 in five districts. The objectives were to compare Sample Positivity Rates (SPR) of Acute Encephalitis Syndrome (AES) cases for JE between vaccinated & unvaccinated districts and observe trend of SPR & Cumulative Incidence in vaccinated districts for three years. METHODS: The study was based on the analysis of surveillance data from all tested AES cases including confirmed JE (IgM ELISA) from all JE testing facilities existent in the state during the study period (2011-13). Calculation of Cumulative Incidence, Odds Ratio (OR) with 95% CI, Preventive Fraction and Chi Square for trend (for SPR) was done. Trend of incidence was assessed by linear regression. RESULTS: In three years, 5 vaccinated districts contributed 945 AES and 88 JE cases (SPR - 9.3%) compared to 1807 and 254 (SPR - 14.1%) JE cases in 14 unvaccinated districts. Effectiveness of vaccination was evident by gradual decline of Odds Ratio in favour of vaccinated districts. Vaccination effectiveness of 68% overall and 80% [OR = 0.20 (0.10 - 0.41)] in below 15 years were observed. Trend of SPR was found significantly declining in most of the vaccinated districts. INTERPRETATION & CONCLUSION: Significant reduction in sample positivity rate over three years in most of the vaccinated districts indicated that the vaccination programme had been gradually effective.

Magnitude, types and sex differentials of aggressive behaviour among school children in a rural area of West Bengal.

BACKGROUND: Aggression affects academic learning and emotional development, can damage school climate and if not controlled early and may precipitate extreme violence in the future. OBJECTIVES: (1) To determine the magnitude and types of aggressive behavior in school children. (2) To identify the influence of age and sex on aggressive behavior. MATERIALS AND METHODS: A cross-sectional study was conducted in Anandanagar High School, Singur village, West Bengal. Participants were 161 boys and 177 girls of classes VII to IX. The students were asked to complete a self-administered questionnaire indicating the types of aggressive behavior by them in the previous month and to assess themselves with reference to statements indicating verbal/physical aggression. RESULTS: Overall, 66.5% of the children were physically aggressive in the previous month: Boys 75.8%, girls 58.2% (P = 0.001); 56.8% were verbally aggressive: Boys 55.2%, girls 61% (P = 0.97). Verbal indirect passive aggression was more common among girls (55.3%) than among boys (22.3%) (P = 0.000 [1.17E(-09)]). Boys were more liable to physical aggression, viz. 60.2% of the boys would hit on provocation compared with only 9% of the girls (P = 0.000 [6.6E(-23)]). Regarding attributes indicating verbal aggression, girls were more argumentative (63.8%) than boys (55.2%) (P = 0.134) and disagreeing (41.8%) compared with boys (33.5%) (P = 0.145). With increasing age/class, physical direct active aggression decreased while physical indirect passive and verbal indirect passive aggression increased. No classes had been taken on anger control/management by school the authorities. CONCLUSIONS: Aggressive behavior was common both among boys and girls. Life skills education/counseling/classroom management strategies are recommended.