Bunmi Ngotleusay’s most valuable assets in her garden aren’t her car or the thick fruit trees, but the big jars containing hundreds of small fish. They are her main protection against the deadly dengue that used to ravage the village just a few years back.

"Before we didn’t know where the mosquitoes live and how they reproduce. We didn’t know how to combat them," remembers Bunmi, who since 2005 has been the Chief of Ban Tat Thong, a small village close to Vientiane.

In 2007, a big dengue outbreak led Bunmi to seek assistance from the Lao Ministry of Health, who found a big epidemic of the Aedes aegypti mosquito in the area.

After Bunmi’s request, a local doctor donated some guppy fish to the village’s pagoda. This small, popular fish specie has proven to be an effective way to eradicate mosquito populations as they eat the larvae floating in water.

The right fish for the fight

A trial study conducted by the governments of Cambodia and the Lao People’s Democratic Republic (Lao PDR) between 2009 and 2011, with the support of the Asian Development Bank (ADB) and the World Health Organization (WHO), showed that the introduction of guppy fish in some communities have resulted in a sharp decline in mosquito larvae in water storage tanks and, consequently, in the number of mosquitoes in the area.

Ban Tat Thong has been one of the pilot programs in Laos to use these small aquatic animals to fight mosquitoes.

From the pagoda, the small fish spread around the village and, today, roughly 90% of the 300 households in Ban Tat Thong have their own anti-mosquito jars.

"We haven’t had any cases of dengue in the village in the last 3 or 4 years," shares Bunmi.

Watch the fish in action (video not from Ban Tat Thong)

No more fear

Kam Sengsavang’s daughter was close to death in 2005 after a mosquito bit her at school. "On the third day we sent her to the hospital because she was in shock," recalls Kam.

She recovered after seven days at the hospital but the memories of high fever and muscle pain remain with her.

"We heard about the fish and wanted to have them to protect ourselves. And ever since we have the fish here, we are not afraid anymore," shares Kam.

Having guppies isn’t enough to ensure a dengue-free environment though. Avoiding any stagnant water where mosquito-larvae can grow is also crucial in guaranteeing the success of the program. And although vector management is important, it’s just one of the steps in eliminating dengue.

"I try to always have everything clean and to empty any container where water can remain. We have to be very careful with [the leftovers of] the coconuts and make the shells face down," says Lee Vanh, a middle-aged mother of three who has a small shop in front of her house.

"With dengue, there is only losing, there is no winning. If villagers are sick, they lose time and money because they cannot work," says Bunmi. "So we work very hard to fight against it."

What are people in your community doing to fight dengue?