An entomological investigation in dengue affected areas during transmission season in district Haridwar, Uttarakhand, India.

Background objectives: Dengue fever is the most common arboviral disease and a serious public health problem and transmitted by Aedes mosquito. Entomological investigations were carried out in dengue affected villages and urban areas of Haridwar district, Uttarakhand to investigate the prevalence, distribution of Aedes mosquitoes and identify high risk areas in Haridwar for proposing control in the risk areas.

Methods: The entomological survey was carried out in all selected localities in different breeding habitats like domestic and peridomestic containers to detect Ae. aegypti breeding with the help of standard entomological techniques. About 777 houses were screened from 12 dengue affected villages and municipal areas of Haridwar district during the month of November 2021.

Results: Out of 777 surveyed houses, 119 (15.3%) houses have Aedes breeding while out of 4360 water containers only 158 (3.6 %) were found positive for Aedes breeding. During survey HI (15.32), CI (3.62), BI (20.33) and PI (35.78) were also calculated. The distribution of Aedes larvae and Breeding Preference Ratio in different type of breeding habitats were also estimated, the highest positivity of Ae. aegypti larvae was observed in underground/ground level cemented tanks (7.94) followed by tray of domestic refrigerator (4.55), discarded tyres (3.72), desert coolers (1.70), plastic containers (1.47), junk materials (1.28), mud-pots (0.58) and flowerpots (0.42) respectively.

Interpretation conclusion: Aedes aegypti mosquito was found to be the dominant species in domestic and peri-domestic breeding habitats, while Aedes albopictus and Aedes vittatus mosquito were also observed in outdoor breeding habitats of the houses. Breeding of Aedes mosquito was found in water storage containers from the same areas where dengue cases were also reported.