PETALING JAYA (THE STAR/ASIA NEWS NETWORK) - At least two people have died of the highly infectious leptospirosis after taking a dip in a waterfall or pond in Malaysia in the last two months, prompting an alert from the health ministry.

The ministry is advising schoolchildren and their parents to be extra careful not to contract leptospirosis, a bacterial infection spread mainly by rodents, while vacationing in natural water spots during the school holidays.

The so-called rat urine disease killed 78 people last year, according to the ministry. Recreational areas accounted for 32 per cent and 22 per cent of outbreaks of the disease in the past two years.

So far this year, there have been 14 outbreaks of the disease and 2,200 people have been infected, the ministry said.

Nearly half of the outbreaks occurred in Selangor while Kelantan accounted for the highest number of cases with 365, followed by Sarawak with 362 cases and Terengganu with 323 cases.

Symptoms for the disease include high fever, diarrhoea, muscle aches and headaches, chills, nausea and vomiting.

In May, a Seremban college student contracted leptospirosis while swimming in the Jeram Toi Recreation Park in Jelebu. He died two weeks later.

Two other vacationers there were also reported to be admitted into the intensive care unit (ICU) after a visit to the park.

In April, an 18-year-old polytechnic student died of leptospirosis after bathing in a picnic spot in Lata Sedim, Kedah a month earlier.

In October last year, the Gunung Pulai Recreational Forest had to be closed for three months after samples from a waterfall there tested positive for leptospirosis.

A single gulp of water from a river, pond or waterfall, coming into contact with soil or swimming in natural water spots with open wounds can expose people to the disease

The health ministry's deputy director-general for public health, Dr Lokman Hakim Sulaiman, said the ministry had conducted tests for the disease in 71 natural water spots nationwide last year and found that 11 per cent, or eight sites, had traces of the disease.

This, however, does not guarantee that sites which tested negative were completely free of the disease, he said.

Areas which are littered with food waste breed rats, which in turn leads to a higher risk of leptospirosis, he added.

"Poor cleanliness or sanitation in recreational areas may increase the risk of contamination," Dr Lokman said.

Scraps left behind by visitors become food sources for rats and other wildlife, whose droppings then poison the natural water sites.

He urged vacationers to keep these tourist sites clean. "Cleanliness makes a difference," he said.

"Avoid leisure activities in potentially contaminated areas, or swimming in waterfalls that are not properly maintained," he advised.

"Avoid swimming in and drinking raw water from natural water bodies or ponds... close skin wounds with waterproof bandages and wear protective clothing like rubber boots and gloves to avoid exposure," he added.