Vol. 7, Issue 4, Part B (2020)

Author(s): Grace Marin, Sony Vincent, Selvanayagam Selvakumar, Subramanian Arivoli and Samuel Tennyson

Abstract: Kanyakumari district is endemic for dengue and reconnaissance of Aedes albopictus in relation to rubber plantations is essential. Natural vertical transmission in Aedes albopictus have occurred in the rural areas of Kanyakumari district, Tamil Nadu, India. In the present study, the surveillance of the dengue vector, Aedes albopictus in selected villages of Kalkulam taluk of Kanyakumari from June 2019 to December 2019, and its impact in the nearby villages was reported. A total of 300 houses and 772 containers in the six villages were surveyed of which 90 houses and 83 containers were tested positive for Aedes larval breeding. Abiotic factors, particularly rainfall assumed an indispensable role in larval breeding, other than temperature, relative humidity, and light intensity. House, Container and Breteau indices computed for the total surveyed villages were 1.88, 0.72, and 1.83 respectively. The occurrence of larval instars (I, II, III and IV) in the coconut shells of rubber plantations examined at 15 per each village were 6.30 ±0.24, 11.50 ±0.80, 14.66 ±0.52, and 7.62 ±0.38 in Anaiady; 5.30 ±0.12, 10.08 ±1.82, 15.18 ±1.50, and 6.90 ±0.14 in Kottarai; 8.68 ±0.86, 9.60 ±0.76, 12.02 ±0.98, and 5.20 ±0.60 in Manacaud; 9.20 ±0.84, 12.60 ±0.36, 14.08 ±2.16, and 6.20 ±0.34 in Pullani; 46.14 ±4.54, 20.14 ±1.88, 20.71 ±3.76, and 34.28 ±4.94 in Thiruvattar; and 8.16 ±0.65, 13.80 ±0.92, 16.25 ±1.80, and 4.80 ±0.26 in Vadakkanadu respectively. All instars upon adult emergence were identified as Aedes albopictus and recorded. Vector-borne diseases were reported in the study area, of which dengue was predominat. Age and sex wise distribution of people in the study area showed men and women of different age groups were affected with the most affected between 20 and 30 years followed by 10 and 20 years. The people residing in and around the rubber plantations were drastically affected by mosquito menace, and as preventive measures, coconut husks were burnt (76%). Studies on bionomics of this vector mosquito is essential, as significant presence of vegetation, particularly rubber plantations are responsible for its prevalence in the study area.