Malaria en route to elimination in two endemic coastal environments of southern India: an eco-epidemiological analysis from 2004 to 2019

Abstract Background Coastal environment and climatic condition are more suitable in propagation of mosquito vectors, and malaria parasite transmission throughout the year. In the present investigation, malaria prevalence in two endemic coastal localities of India viz., Besant Nagar (Chennai district) and Pamban (Rameshwaram district) were analysed from 2004 to 2019. Methods Malaria surveillance data and entomological data from malaria clinic were used to investigate epidemiological parameters. The annual malaria cases were correlated with highest maximum temperature. Results The analysis showed that the malaria case (P.v. and P.f.) report were directly proportional to the temperature increase. Malaria cases were remarkably increased from 2004 to 2011 and subsequently, both P.v. and P.f. cases were drastically reduced till 2019. P. vivax was higher than P. falciparum and male population was found to be more affected. Mixed infection of P.v. & P.f. was observed only in Besant Nagar site (0.3%). The most affected age group was adult age group (15 years and above) in both Besant Nagar (76.1%) and Pamban (69.5%). Conclusions Improved surveillance, complete treatment and integrated vector control activities showed declining trend of malaria cases in both the coastal sites towards malaria elimination.