THE Ministry of Health (MoH) started an impromptu, emergency campaign January 30
against an outbreak of mosquitoes breeding as a result of Phnom Penh's sewage
cleanup. The MoH will spray insecticide for at least a week in some of the
city's 76 communes, said Dr Duong Socheat, director of the National Malaria
However, the sudden outbreak should prove merely annoying
rather than a health risk, said the World Health Organization's malaria expert
Dr Stefan Hoyer.
"The Culex mosquito has found an ideal breeding ground
in the open sewage canals on Monivong Boulevard," said Dr Hoyer, "but Culex
cannot transmit dengue fever or malaria, and the dengue-carrying Aedes mosquito
cannot breed in sewage water."
The mosquitoes have been plaguing more
than just the citizenry, said Dr Socheat - many government officials had
complained to his department about the problem.
Chanthy is a resident in
the city's Boeung Tumpun commune and lives near the sewage system. He said the
insects had proved an expensive nuisance.
"Every night the mosquitoes
come and bite me. Even though I spray insecticide, they keep flying back," he
said. One bottle of insecticide costing 6,500 riel ($1.60) was lasting him only
three days. "I have already finished four bottles, but still they keep coming
everywhere. You can see my hands are covered with bites."
What is bad
news for Chanthy is good news for the pest-controllers. Huth Daravuth is the
market manager for the Chheng Khieng Import Export Company. He said sales, which
normally dropped in the hot season, had shot up this year.
sell 30,000 bottles of insecticides and 3,500 boxes of mosquitoes coils each
month," he said. "This year I have sold 42,000 bottles and 5,000
The city's more affluent residents have tried the pest-control
companies. Bora Moeu, general manager of Pestbusters, said he had gained 30 new
customers since December.
"Before there were only foreign clients, but
now Cambodian customers come to us as well," he said. The service comes at a
price: customers pay $60 for a one-time spray that keeps their homes mosquito
free for about four days.
Moeu said sprays and mosquito coils were fine
as a short-term solution, but it was more important to track down the larvae.
WHO's Dr Hoyer said that was exactly what the campaign would do by following the
trail back to the sewers where the insects breed.
"It is much more
efficient to kill the larvae than the adults," he said.
from WHO in Geneva showed the amount of larvacide needed to kill larvae in
sewage would be at least 12 times that needed for clean water.
not a practical solution because we need to keep enough larvacide to prevent a
[potential] dengue outbreak in May," he said. An outbreak of dengue fever in
January 1998 resulted in 256 cases among Phnom Penh's children, said the NMC. Dr
Hoyer said a better solution would be a light covering of oil on the stagnant
water to suffocate the larvae and breeding mosquitoes.
"The MoH and WHO
have been concerned to find a practical, long term solution because this kind of
sewerage work is likely to continue," he said. The MoH would now keep an eye on
future sewerage work in the city to prevent further outbreaks.
should take the war against mosquitoes - which survive for around one month -
into their own homes, said Dr Hoyer. Spraying water outlets in the bathroom with
insecticide, pouring small amounts of non-toxic oil in vases and spraying
insecticide early in the morning are all effective ways of dealing with the