This was revealed during the National Mosquito Control Week conducted by the Epidemiology unit of the Health Ministry from May 26 to June 1.
Out of 4,599 private companies inspected, a staggering 1,220 were identified as breeding grounds for mosquitoes.
This negligence has sparked outrage, prompting legal action against 981 of these establishments and 3,121 notices.
Meanwhile, out of 93,874 premises inspected nationwide, nearly 5,000 were found with mosquito larvae. Over 25,000 houses were flagged as potential breeding sites.
The week covered 15 districts in Sri Lanka including Colombo, Kalutara, Kandy, Gampaha, Jaffna and Ratnapura.
According to the Epidemiology unit, 25,095 dengue cases have been reported from all over the island as of June 3.
DM