After taming malaria, Singapore fights dengue

 
Share this on your social network:
   Facebook Twitter Google+    Comments Mail

SINGAPORE, Dec 12: Did you forget to empty the stale water in the bottom of your flower pot? In tropical Singapore, you could be fined S0 if environmental inspectors find mosquito larvae in your home because of such carelessness.

Draconian measures, such as giving inspectors the right to enter people's homes to check on the status of their flower pots, have helped Singapore eradicate malaria.

But while these tactics have reined in the collection of stagnant water which provides a breeding ground for the malaria-carrying Anopheles mosquito, they have proved less effective in tackling dengue fever, which is carried by the Aedes mosquito.

''With malaria, you take care of the brackish water and it's OK,'' said S. Satish Appoo, head of the National Environment Agency's (NEA) environmental health department. Singapore was declared malaria-free by the World Health Organisation in 1982.

''Development has helped to eliminate indigenous cases of malaria, but with urbanisation you have an increased risk of dengue because the Aedes mosquito is an urban insect and very well adjusted to the urban environment. Bottle caps, tin cans these are the places where it can breed.'' With its equatorial climate, heavy rainfall, dense living conditions and economic dependence on trade and tourism -- its port is the world's busiest while its international airport handled over 32 million passengers last year -- Singapore should serve as the perfect petri-dish for breeding diseases.

Yet the island state has managed to keep most of them at bay with stringent regulations and tough enforcement -- and its experience could offer lessons for other countries.

Its weapons against malaria and dengue consisted of legislation, an emphasis on public housing and urbanisation, education, and the destruction of mosquito breeding sites.

QUARANTINE AND FINES

 During the 1960s, the government embarked on a programme to move people out of Chinatown's slums and rural communities, or kampungs, into new, high-rise public housing with better sanitation and health care.

Presently, the vast majority of Singaporeans live in high quality public housing. Life expectancy, at 79-80 years, is higher than in the United States while per capita gross domestic product has soared from US2 in 1965 to 26,836 dollar in 2005, on a par with Spain.

But modernisation was not enough to keep some diseases under control so the authorities stepped in.

Under the Infectious Diseases Act of 1976, cases of dengue, malaria, tuberculosis, venereal diseases and others must be reported to the authorities, who can quarantine individuals, as happened during the outbreak of SARS in 2003.

Another piece of legislation, the Control of Vectors&Pesticides Act, which dates from 1968, gives inspectors the right to enter homes or other places in search of mosquito breeding sites -- like flower pots and containers that collect water -- and to fine offenders.

For households, the fines start at 100 dollar; for building sites, they can run to 20,000 dollar and can include a jail term.

As the number of dengue cases surged alarmingly in 2005, 1,984 households were caught harbouring mosquito larvae and fined, according to the NEA.

Such policies can work here because of the government's zero tolerance for corruption and the emphasis on law enforcement on an island with a population of just 4.4 million.

GUTTERS AND MANHOLES

 But despite authorities' efforts, dengue has clung on in urban areas. To fight it, the government has urged changes to roof gutters, manhole covers and even the supports used for hanging laundry -- all of which were found to trap rain water, providing temporary breeding sites.

This year, the NEA started to clear potential breeding sites ahead of the July-August hot rainy season, when dengue outbreaks are more common.

In built-up areas across the island, it's common to see men wearing masks and swathed in protective suits ''fogging'' gardens and public spaces. But some say such pesticide-spraying is far from effective for killing mosquitoes.

''We want to minimise the use of fogging,'' said Christina Liew, a medical entomologist at Singapore's Environmental Health Institute.

''We're now using a more environmentally friendly method, a bacteria which attacks the larvae. Our research shows it destroys the mosquito larvae. You can spray about once a week or use it in doughnut form, putting it in drains, or in construction sites.'' Even though Singapore has eradicated malaria, its neighbours have not and dengue outbreaks occur every year in the region -- thousands of people have been infected in India this year, for example.

Singapore is keen to encourage research into vaccines and treatment for some of the more common tropical diseases that still affect its people and others worldwide, like dengue.

Swiss drugmaker Novartis AG has started a research and development programme in Singapore, working on areas such as dengue and tuberculosis.

''It was a logical extension of our research. Singapore was interested in attracting talent,'' said Alex Matter, director of the Novartis Institute for Tropical Diseases in Singapore.

''Dengue is an exploding disease, it spreads like wildfire worldwide. The fact that this year is calm doesn't mean the problem is solved. We still don't have a vaccine, diagnostics or drugs.''

REUTERS

Write a Comment

Videos

FIVE KILLED IN ROAD ACCIDENT IN BURDWAN, FOUR LEFT INJURED

FIVE KILLED IN ROAD ACCIDENT IN BURDWAN, FOUR LEFT INJURED