Vector-borne diseases (VBDs) exert a substantial burden across the world, especially in tropical countries. Malaria, chikungunya, dengue, visceral leishmaniasis, lymphatic filariasis and Japanese encephalitis are among the public health concerns for India. One of the major pillars for the containment of VBDs is vector control and different tools have been employed for several decades. These range from chemical insecticides used in indoor residual sprays, space sprays, fogging, treated bednets and larvicides to biological control methods such as larvivorus fishes and environmental control and modification measures such as source reduction. However, these methods are increasingly becoming less effective due to several reasons such as insecticide resistance, outdoor biting, behavioural changes in vectors for biting and resting, climate change, movement of population, vector incursion to newer areas and others. It is essential to develop and test new tools for vector control to surmount these challenges. Though focusing on India’s public health concerns, the new tools enumerated here can be tested by any country with similar epidemiological and environmental conditions. The promising new vector control tools are insecticide-treated nets with synergist and/or pyrrole chlorfenapyr, alternatives/additions to synthetic pyrethroids like neonicotinoids, clothianidin for indoor residual spray, newer formulations such as Bacillus sphaericus for use in larvicides, attractive toxic sugar baits, especially to curtail outdoor transmission, endectocides like ivermectin for use in animals/humans, insecticidal paints, spatial repellents, insecticide-treated wearables and others. Genetic modification technologies (Sterile Insect Technique/Incompatible Insect Technique/Wolbachia transfection) are also upcoming strategies. Among the six VBDs, India is committed to the elimination of three (malaria, visceral leishmaniasis and lymphatic filariasis) and it will require additional and/or novel tools to overcome the roadblocks in our current journey to the goal of control/elimination of these VBDs.

Background: Dengue is rapidly expanding climate-sensitive mosquito-borne disease worldwide. Outbreaks of dengue occur in various parts of India as well but there is no tool to provide early warning. The current study was, therefore, undertaken to find out the link between El Niño, precipitation, and dengue cases, which could help in early preparedness for control of dengue. Methods: Data on Oceanic Niño Index (ONI) was extracted from CPC-IRI (USA) while the data on monthly rainfall was procured from India Meteorological Department. Data on annual dengue cases was taken from the website of National Vector Borne Disease Control Programme (NVBDCP). Correlation analysis was used to analyse the relationship between seasonal positive ONI, rainfall index and dengue case index based on past 20 years’ state-level data. The dengue case index representing ‘relative deviation from mean’ was correlated to the 3 months average ONI. The computed r values of dengue case index and positive ONI were further interpreted using generated spatial correlation map. The short-term prediction of dengue probability map has been prepared based on phase-wise (El Niño, La Niña, and Neutral) 20 years averaged ONI. Results: A high correlation between positive ONI and dengue incidence was found, particularly in the states of Arunachal Pradesh, Chhattisgarh, Haryana, Uttarakhand, Andaman and Nicobar Islands, Delhi, Daman and Diu. The states like Assam, Himachal Pradesh, Meghalaya, Manipur, Mizoram, Jammu & Kashmir, Uttar Pradesh, Orissa, and Andhra Pradesh shown negative correlation between summer El Niño and dengue incidence. Two - three month lag was found between monthly ‘rainfall index’ and dengue cases at local-scale analysis. Conclusion: The generated map signifies the spatial correlation between positive ONI and dengue case index, indicating positive correlation in the central part, while negative correlation in some coastal, northern, and north-eastern part of India. The findings offer a tool for early preparedness for undertaking intervention measures against dengue by the national programme at state level. For further improvement of results, study at micro-scale district level for finding month-wise association with Indian Ocean Dipole and local weather variables is desired for better explanation of dengue outbreaks in the states with ‘no association’.

Aedes aegypti, the primary vector of dengue generally breeds in intradomestic and peridomestic containers made up of different materials, i.e. plastic, iron, rubber, earthen material etc. The material of container is likely to affect the temperature of water in container with variation in environmental temperature. The present study was aimed to determine the effect of different container materials on larval development of Ae. aegypti at different temperatures. Newly hatched I instar larvae (2-4 h old) were used in the study and experiments were conducted using three different containers made up of plastic, iron and earthen material. Three replicates for each type of container at 22, 26, 30, 34, 38, 40, and 42°C were placed in environmental chamber for the development of larvae. At temperatures >22°C, 50% pupation was completed in earthen pot within 4.3±0.6 to 6.3±0.6 days followed by plastic containers (5±0 to 8±0 days) and iron containers (6±0 to 9±0 days). Developmental time for 50% pupation in the three containers differed significantly (p < 0.05) at all the experimental temperature ranges. A significant variation was found in the temperature of environmental chamber and the temperature of water in three types of containers (p < 0.05). The difference in the temperatures of water in different containers resulted in significant variations in the developmental period of larvae. More than 35°C temperature of water was found inimical for pupal development. The results revealed the variation in temperature of water in different types of containers depending on the material of container, affecting duration of larval development. As the larval development was faster in earthen pot as compared to plastic and iron containers, community should be discouraged for storing the water in earthen pots. However, in view of containers of different materials used by the community in different temperature zones in the country, further studies are required for devising area-specific preventive measures for Aedes breeding.