After the deluge, beware
Health authorities fear that the present wet weather
could lead to a dengue epidemic by December.
Dr. Padmal De Silva, Medical Officer of Epidemiology
and Statistics in the Public Health Unit (PHU) of the Colombo Municipal
Council (CMC), said the heavy rains experienced throughout the island
are likely to cause a sudden increase in dengue cases towards the
end of the year.
“We are using biological techniques to destroy
the dengue larvae but we need a more hands-on approach where the
public makes an effort to clear their own neighbourhoods,”
From January to October this year 630 dengue cases
have been reported as against 645 cases during the corresponding
period last year.
In 2004, which was known as the major dengue epidemic
year in Sri Lanka, 1,030 cases of dengue were reported to the PHU
while over 15,000 cases were reported island-wide.
The dengue disease usually reaches its peak in
the two-week period after a rainy spell, when stagnant water collects
and creates prime breeding grounds for these mosquitoes.
The PHU is currently using a system called COMBI
(Communication for Behavioural Impact) which is recommended by the
World Health Organization (WHO) as the best way to fight the dengue
The COMBI method aims to get people to spend 30
minutes a week to clean their premises and the area surrounding
“This method is more about educating the
public on the disease and its spread and also getting the public
involved in the process of clearing breeding sites. It is fairly
simple to eradicate this menace but the level of public cooperation
has not been satisfactory,” he said.
Countries such as Singapore and Cuba carried out
the more successful campaigns on the elimination of dengue, by using
public awareness as a weapon but Sri Lanka’s situation poses
many problems in using this method.
The PHU of the CMC currently has seven Medical
Officers, around 45 Public Health Inspectors and the same number
of Health Instructors, while there are over 1.25 million people
in Colombo and over 250,000 residences.
“Clearly the CMC is not in a position where
we can send leaflets to each and every home, nor clear the entire
city of breeding grounds, but by carrying out a more efficient and
long running dengue awareness campaign, we can bring round people
to our cause,” Dr. De Silva said.
The fact that 50% of reported dengue cases are
of school children is also a major concern with the health authorities
and has caused them to organize large-scale dengue elimination programmes
in schools as well.
Dr. De Silva said the PHU ran a programme where
school children were employed to clear mosquito breeding grounds
in and around their schools within a 500-metre radius.
“Programmes like this have helped bring
school children cases down to 30% but the education authorities
are not cooperating with us now since students are not allowed to
leave their school premises during school hours,” he said.
He also said the PHU had the authority to prosecute
any civilians who did not adhere to warnings concerning the cleanliness
of their homes.
If any homes harbouring mosquito breeding grounds
or even potential ones are reported to the PHU, a notice requesting
the owners to clear their premises is issued and an inspection done
after three days. If the breeding grounds are not cleared within
a week legal action is taken by the PHU.
“Currently the fine for the offence varies
from Rs, 1,000 to Rs. 5,000, but the Government is considering raising
the fine to Rs. 25,000,” Dr. De Silva said.
Dr. P. Kariyawasam, Chief Medical Officer of the
PHU told The Sunday Times that dengue cases in Colombo were on the
rise and even though statistics show an improvement from the past
three years, the uncertain weather patterns could cause a major
dengue epidemic in December, within the municipal limits.
“We usually get many reports of dengue cases
during October but this time we have been able to keep the number
of cases under control,” he said.
|Points to remember
Dengue mosquitoes are
predominantly found in urban areas and are known to be day
Dengue mosquitoes breed in pools of stagnant, clear water
that collect in ditches, tins, pots, coconut shells, etc.
Studies show that discarded rubber tyres are the dengue mosquito’s
favourite breeding ground.
Their peak biting times are between 7 a.m. and at 7 p.m.
so school children and people getting back home after work
are especially vulnerable.
The dengue mosquito has a biting radius of 250 metres and
is known as a relatively lazy mosquito. However it is a compulsive
biter and would follow one person for long periods of time.
The dengue mosquito is an outdoor mosquito and most dengue
victims are infected outside their homes.
Dengue mosquitoes are most active two weeks after heavy
Dengue mosquitoes do not move too far away from their breeding
grounds so most victims are bitten by mosquitoes breeding
in their own gardens.