The city has more Culex mosquitoes than the dengue-causing Aedes aegypti or malaria-causing Anopheles mosquitoes, and this may require caution as the Culex is behind the crippling filariasis and the much-dreaded Japanese encephalitis.
More caution should be paid in view of long term threat, as it is a hardy genus and survives several adversities, say entomologists.
Entomology teams out on streets and inside homes spraying, fogging and carrying out anti-larval operations have discovered that six out of every 10 mosquitoes in the city are of Culex genus. Aedes aegypti, on the other hand, constituted 20% to 30%, while the presence of Anopheles is negligible, shared GHMC Chief Entomologist A. Rambabu.
Entomology workers are capturing mosquitoes by the use of aspirators and suction tubes, which are later analysed to identify the species and disease causing virus.
While Culex larvae are found in dirty waters mostly in and around the Musi River, those of dengue-causing mosquito are largely found indoors or in open plots, he said.
Breeding spots
“Most often, hundreds of Aedes aegypti larvae are found breeding in the plates kept underneath the flowerpots. We once counted 500 to 600 larvae in a single plate at a VIP’s home. There could be hundreds of such pots in each home, and the larvae could be in millions,” Mr. Rambabu said, stressing the need for community involvement in vector control operations.
Besides, rain water deposited in discarded cups around hotels, and empty coconut shells around hospitals and tyres hanging out in auto mobile workshops serve as effective breeding spaces for the larvae.
Locked houses and discarded corners inside homes often become breeding grounds, Mr. Rambabu said.
While Culex mosquito has not become dangerous yet, it certainly has the potential and its eradication is a difficult job too. The genus has high resistance, and unlike Aedes aegypti, which can move only within half a kilometre radius, its infecting range is five to six kilometres.
“In case people arriving here from outside the State carry Encephalitis virus, we might become more susceptible. In such a situation, having so many Culex mosquitoes could prove disastrous. Hence, vector control should be taken rather seriously by community members too by keeping their homes and surrounding areas clean and free of larvae,” Mr. Rambabu said.
Coconut oil remedy
While the department is going about spraying chemicals and larvicides, and carrying fogging operations wherever there is a demand, people may follow simple remedies such as coconut oil at home, he suggests.
Coconut oil is an effective larvicide, and may be mixed without harm in stored water and in the plates used for flower pots, he said.
