Mosquito fish seen effective weapon vs dengue

DAGUPAN CITY—One of the best weapons to beat dengue-carrying mosquitoes is swimming under everyone’s noses and is considered by some fishermen as a pest.

The pest, known as mosquito fish or “tuyong” locally, feeds on mosquito larvae, said Roberto Garcia, a marine expert who propagates organic “bangus” (milkfish).

Fishermen usually poison tuyong because it competes with bangus for food.

Garcia, however, said tuyong “can be put in canals and other bodies of water where dengue mosquitoes breed as a sort of biological control of the deadly mosquitoes.”

“Mosquito fish was introduced all over the world to control malaria and perhaps health officials have forgotten about [its existence in the Philippines] … that it can be used to control dengue,” said Dr. Westly Rosario, chief of the Bureau of Fisheries and Aquatic Resources’ National Integrated Fisheries Technology and Development Center here.

Garcia said tuyong was introduced in the country’s waters in the early 1900s.

Rosario said most fish groups, like tilapia, can control mosquito population, but tuyong is apt for street canals.

Tuyong looks like anchovy, has silvery skin and fan-like tail, according to Rosario.

The female tuyong is usually bigger than the male and often has a bulging belly, he said.

Garcia said every available resource should be tapped to prevent dengue. “[The] mosquito fish has a good potential to control dengue-carrying mosquitoes because it is abundant and free, environmentally friendly, indigenous to the area and [has] proven [to be] effective,” he said.

He said a system for coordination, production and distribution of tuyong to dengue-affected areas could be established. “Even in areas where dengue is not [prevalent], the mosquito fish can be stocked as a preventive measure. It could be as simple as getting a bucket [filled with] fish and throwing them into stagnant waters,” he said.

Dengue has plagued various towns of Pangasinan, including this city.

Garcia said other countries, among them the United States, promote mosquito fish as a biological weapon against disease-carrying insects.

“[Tuyong] is appropriately called mosquito fish because of its ability to feed voraciously on mosquito larvae as part of its natural diet,” said Garcia.

“Studies show that this biological control of the production of mosquitoes in stagnant or running water has been proven effective and that it has become a critical part of the mosquito eradication program,” he said.

Citing his own experience, Garcia said he has seen for himself the effectiveness of tuyong as a tool against mosquitoes in his fishponds.

Thousands of mosquito larvae grow uncontrolled in the fishponds but disappear after tuyong is introduced, said Garcia. Yolanda Sotelo, Inquirer Northern Luzon