The World Health Organization (WHO) declared Sri Lanka free of malaria on Tuesday (6 September) and termed the feat a "remarkable" public health achievement in the country. The Asian nation was one of the most malaria-affected countries in the world.

It becomes the second country in the UN health agency's Southeast Asia region – after Maldives – to be declared malaria-free. According to WHO, there were no locally transmitted cases of the mosquito-borne disease detected in the country in the last three-and-a-half years, hence it was awarded the certification.

Reports said that Sri Lanka brought down the number of malaria cases from 264,549 in 1999 to a zero in November 2012, which put the country ahead of its neighbours such as India, Bangladesh and Thailand. When a country has zero locally acquired malaria cases for at least three consecutive years, WHO can certify it as malaria-free.

"Sri Lanka's achievement is truly remark able. In the mid-20th century it was among the most malaria-affected countries, but now it is malaria-free," WHO Regional Director, Dr Poonam Khetrapal Singh said.

"This is testament to the courage and vision of its leaders, and signifies the great leaps that can be made when targeted action is taken."

The WHO credited the island nation's success to a change in Sri Lanka' strategy that it deployed after malaria cases soared in 1970s and 80s. It had introduced mobile clinics for patients and improved public health awareness campaigns to combat the disease.

"The change in strategy was unorthodox, but highly effective," WHO said in a statement. Sri Lanka's Health Minister Dr Rajitha Senaratne said: "We are very proud of this achievement and it should be dedicated to our exceptional medical professionals."

Former director of Sri Lanka's Anti-Malaria Campaign Dr Risintha Premaratne told Wall Street Journal, "Our biggest challenge is to ensure monitoring. International funding for Sri Lanka's anti-malaria campaign ends in 2018 and after that the full financial responsibility falls on the government."

Malaria, a parasitic disease, can be prevented and cured. However, hundreds of thousands of children are still dying every year, which is said to be most common in developing nations. Sub-Saharan Africa accounted for nearly 90% of the total number of cases and deaths due to malaria. There were more than 214 million new cases of malaria detected across the world, while 438,000 people perished in 2015.

In the Southeast Asia, approximately 1.3 billion people are said to be at risk of contracting malaria.