New Delhi, Aug. 2 -- The Centre has asked states to tighten dengue surveillance and step up mosquito control as the monsoon creates favourable conditions for mosquito breeding, with health authorities also warning that developing El Niño conditions could increase the risk of vector-borne disease transmission, according to two officials and a health ministry communication seen by Mint.

Data from the National Centre for Vector Borne Diseases Control (NCVBDC) shows 13,336 dengue cases and 12 deaths have been reported so far this year. Against that backdrop, the ministry has instructed states to expand laboratory testing using ELISA-based NS1 and IgM kits, submit daily reports through its online portal, and intensify larval source manag...