“At night there are so many mosquitoes, we can’t stay outside,” says young, smiling Madhavi Sharma, whose family farms rice and cattle in the southern Bhutanese village of Samteling. They often spend their evenings in the kitchen, where they cook over an open fire whose smoke drives the insects away.

Sharma was educated up to Grade 10 (up to 16 years old), and through word of mouth and government campaigns has absorbed plenty of information about the threats of malaria and dengue fever, which are both transmitted by mosquitoes. The Sharmas don’t keep stagnant water lying around. And they use the long-lasting insecticidal nets distributed for free by the government: there’s even a little one for the 14-month-old baby, who sleeps on a homemade hammock crib downstairs.

Their home is also sprayed with insecticide twice a year. However, the Sharmas have plastered the walls of their house with mud and dried cow dung, making the indoor residual spraying (IRS) ineffective for now. The house has openings in the walls, rather than doors and windows, so nets are especially important.

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The nets, the spray and the public awareness all point to the Bhutanese government’s strong push to reduce malaria, which began in the 1960s. Cases have dropped dramatically, from a 1994 peak of about 40,000 cases (including 68 deaths) to 54 in 2018 (of which only six cases were indigenous). The sole fatality in 2017 was a 21-year-old soldier deployed to the Bhutan-India border who arrived at a hospital too late for doctors to treat his cerebral malaria.