Community engagement to control dengue and other vector-borne diseases in Alappuzha municipality, Kerala, India.

Introduction Vector-borne diseases (VBDs) are a serious threat in many Indian states, including Kerala. Community-based decentralized planning and engagement are effective strategies that can make positive behavioral changes to control VBDs. Methods This community-based implementation research was conducted during November 2016 - October 2018 in Alappuzha municipality in Kerala, India. It was conducted in two phases. In the first phase, formative research was conducted to know the community's profile and perceptions and thus to plan and develop an appropriate intervention. Baseline data on some entomological indicators were also collected. These data were used to assess the impact of the intervention by comparing with the post-intervention data. In the second phase, an intervention through the community's engagement was implemented in selected wards. The activities included the formation of community committees and the vector control and source reduction activities with the community engagement and inter-sectoral coordination. Results The intervention resulted in a positive change among the community to engage in vector control activities. These efforts along with inter-sectoral coordination resulted in successfully implementing vector source reduction activities. In both wards, pre- and post-intervention entomological data (house index: 16.7 vs 6.0 and 64.2 vs. 8.6; container index: 24.8 vs. 12.1 and 37.7 vs. 18.1; and Breteau index: 21.3 vs. 7.3 and 47.7 vs. 8.6) revealed a considerable vector source reduction. Conclusion The findings of this study suggest considering and including community engagement in public health policy as the main thrust to control VBDs.

FlaB PCR-based identification of pathogenic leptospiral isolates.

BACKGROUND/PURPOSE: The genus Leptospira comprises pathogenic and saprophytic strains. Conventional methods for the identification of pathogenic leptospiral isolates are cumbersome and laborious. In view of these limitations, the search for alternative methods have been focused on DNA based techniques. In this study, we have developed an effective method for the rapid identification of pathogenic and saprophytic leptospiral isolates based on DNA-based techniques. METHODS: A polymerase chain reaction(PCR)-based approach was developed using specific primer sets (flaB, G1-G2, B64I-II, and A-B) to differentiate pathogenic and saprophytic leptospiral strains. Fifty-five leptospiral isolates were used for this study. The pathogenic status of the isolates was compared with the results obtained using conventional techniques, which included growth in the presence of 8-azaguanine and growth at 13 degrees C. RESULTS: In this analysis, 46 leptospiral isolates were confirmed as pathogenic and nine were confirmed as saprophytic. PCR with the A-B primer set yielded an amplified product of 331 bp in all of the pathogenic and saprophytic isolates. The other primer sets, G1-G2, B64I-II and flaB, yielded products of 258 bp, 568 bp, and 793 bp, respectively, exclusively for the pathogenic leptospiral strains. None of the saprophytic strains yielded products with these primer sets. CONCLUSION: The flaB-specific primers consistently yielded an amplification product for all of the pathogenic leptospiral isolates, indicating the presence of the flaB gene only among pathogenic leptospires, and making this a useful tool for distinguishing between pathogenic and saprophytic leptospires. The efficiency of PCR-based identification corroborates the implementation of these techniques for the identification of pathogenic and saprophytic leptospiral strains.