Beware of that bite
By.Prof. J. Sarath Edirisinghe
Malaria is one of the most persistent diseases
of the tropics. The disease is caused by a protozoan, a tiny single celled
organism of the genus Plasmodium. Four species of Plasmodium
infect man. Of these four, only two species, namely Plasmodium vivax
and Plasmodium falciparum are found in Sri Lanka. A third species,
Plasmodium malaria, once prevalent in Sri Lanka has not been reported
since the sixties. Malaria is naturally transmitted to man by the bite
of an infected female mosquito of the genus Anopheles.
When a mosquito bites a person with malaria and sucks up blood, malarial
parasites present in the blood of the infected person enter the body of
the mosquito with the blood meal. These parasites multiply and develop
in the body of the mosquito. After a period of about 10-14 days the infective
forms of the parasite become ready to be passed on to a human being. If
the mosquito now bites a healthy person, the infective forms of the malarial
parasite enter the body of the healthy person making him/her ill with malaria.
The principal transmitter of malaria in Sri Lanka is Anopheles culicifacies.
Two other species of mosquito of the genus Anopheles are incriminated
as alternate transmitters of malaria. They transmit the disease only under
exceptional circumstances.
Although mortality due to malaria is low in Sri Lanka, the disease still
kills a large number of people in other endemic countries such as Thailand
and countries of the African continent. It is unfortunate that deaths continue
to happen when it is clearly known that the disease is curable and preventable.
In a country like Sri Lanka where intensive anti-malaria work had been
in operation since the last major epidemic in 1934/1935, it is surprising
that a considerable proportion of the population remains blissfully unaware
of the nature and the possible preventive measures available against this
dreaded disease. Many do not come in time for proper treatment while a
few may not have easy access to a health-care facility within a reasonable
distance.
Following the devastating malaria epidemic in 1934/1935 which affected
the whole country, anti-malaria measures such as oiling and application
of Paris green to mosquito breeding sites were instituted with the hope
of reducing mortality and lowering the number of cases to a minimum level.
With the introduction of DDT for indoor spraying in 1946 to kill adult
mosquitoes resting inside houses, the incidence of malaria in Sri Lanka
fell dramatically. The whole world watched the amazing achievements of
the tiny Indian ocean island heading for the impossible - eradication.
By 1963 the number of malaria patients reported was at an all time low
- 17 cases. Due to many reasons, particularly due to lapses in proper surveillance,
the hopes for a land without malaria were shattered as malaria patients
began to re-appear in regular fashion in some parts of the country.
The end of the sixties was the beginning of a long continued epidemic
once again, this time with high morbidity but, with low or no mortality
compared to that of 1934/1935. In the early seventies the mosquito responsible
for the transmission of malaria in Sri Lanka, Anopheles culicifacies
showed signs of resistance to DDT, the major weapon at hand to interrupt
transmission. In 1977 in Sri Lanka abandoned and prohibited DDT use and
changed over to malathion as the insecticide for indoor spraying
in endemic areas. Once again the country witnessed a lowering of incidence
of malaria. Unfortunately for Sri Lanka, history repeated itself, this
time with a vengeance and the saga of malaria continues to this day, unabated
and undefeated. In October 1982 once again an increasing incidence of malaria
was noted.
Despite continued anti-malaria measures the incidence has not dropped
by an appreciable degree so far. The situation was conpounded by the unsettled
conditions, prevailing in the country due to the ongoing war in some parts
of the island. The latest strategy in the control of the malaria mosquito
is the use of three insecticides in rotation in order to minimize the development
of resistance by mosquito to malathion or to one particular insecticide.
The insecticides in use are malathion, fenitrothion and lamda cyhalothrin.
According to the Annual Health Bulletin (1996), the objectives of the
malaria control programme are:(1) To reduce the incidence of malaria to
a level that the Annual Parasite Incidence (API) would not exceed 10 per
1000 population by the year 2001. The population refers to those living
in areas at risk for malaria. (2) To minimize the proportion of falciparum
malaria infections. (3) To eliminate mortality due to malaria (4) To prevent
epidemics of malaria and (5) To prevent malaria in pregnant women.
A slight reduction in malaria cases seen during 1995 has been overshadowed
by a 30% increase in the incidence in 1996. The largest number of patients
reported in 1996 was from the Northern and Eastern provinces. This was
mainly because of the operational difficulties in the unsettled areas of
the island and the influx of massive numbers of refugees into these areas.
During 1996, 1.3 million blood films were screened for malaria. Of these,
14.3 per cent were positive for malaria. P. vivax, the less harmful
parasite was responsible for 75.6 per cent of all positive patients. The
rest was due to P. falciparum.
In Sri Lanka malaria is endemic (year round transmission of the disease)
in the dry zone. Continuous transmission of malaria may or may not take
place in the intermediate zone. But this zone is prone to malaria epidemics
(sudden outbreaks of malaria involving a large number of people) from time
to time. There is no transmission of malaria in the wet zone. However,
sporadic outbreaks of malaria occur in this zone when the South West monsoon
fails leading to pool formation in drying up river beds. The western province
is relatively free of malaria.
Any episode of fever in a person from a malaria endemic area or in a
person who has visited malaria endemic areas should be investigated as
a case of malaria. Many people who are long-standing residents of malaria
endemic areas may experience somewhat mild symptoms. Such persons who have
experienced malaria over and over again will be aware of the routine of
visiting the nearest health facility where blood obtained by a finger-prick
is examined and if positive treated with the appropriate drugs.
The first line of treatment is with two drugs-chlorequine, large white
tablets and primaquine, small yellowish or brown tablets. For patients
with P. vivax infections ten chloroquine tablets (large white) are given
to be taken as follows. Four tablets on the first day (600mg) followed
by four tablets (600mg) on the second day and two tablets (300mg) on the
third day. The primaquine (small yellowish) is given at a dose of one tablet
twice a day (15 mg) for the five days for people of malaria endemic areas
and for fourteen days for people from non-malaria areas. It is advisable
to take the large white tablets after a meal as some patients experience
nausea and vomiting when the drug is taken on an empty stomach. It is important
that the full course of drugs is followed by patients. For patients with
falciparum malaria the same course of chloroquine is given with
a single dose of six tablets of primaquine (45 mg). Patients should note
any adverse effects of the drugs being taken such as dark urine when on
primaquine therapy.
Such information should be communicated to their attending doctors without
delay. Treatment for malaria should always be prescribed by a doctor. Self-medication
is dangerous and should not be attempted.
Those who continue to have fever despite chloroquine being taken have
to be blood filmed again and if growing stages of the parasite are still
present in peripheral blood an alternative drug should be given. The alternate
drugs used in chloroquine resistant falciparum malaria include quinine
with or without tetracycline, and pyremethamine and sulphadoxine combination.
All patients with severe symptoms have to be hospitalized and if oral drug
therapy is impossible due to vomiting or unconsciousness, intravenous drug
therapy should be started immediately. Pregnant mothers with uncomplicated
malaria (P. vivax or P. falciprum) during the early part of the
pregnancy should be treated with chloroquine alone. Primaquine is given
to such patients after the delivery of the baby.
To achieve the objectives of the anti-malaria programme a large part
of the responsibility rests on the general public. The ways in which we
could help are by seeking treatment early if malaria is suspected, following
instructions when receiving drug treatment, completing the course of treatment
and also by extending their support to the anti-malaria campaign to carryout
their work properly. Such measures would help to bring down the incidence
of malaria in this beautiful island nation of ours.
Your Health
Do curry eaters get the runs?
By Dr. Sanjiva Wijesinha
So the Australian test cricketers have finally admitted the truth? they
can't tolerate Indian curries.
On tour in India last month Mark Taylor's team found the local food
so intolerable that 2000 tins of baked beans and spaghetti had to be specially
flown in from home just to feed the touring party. Although some claim
it was just a publicity stunt by certain baked beans manufacturers, the
complaint about the local food was made just in time for the Aussies (bad
losers at the best of times) to have a ready-made excuse to explain their
loss to India in the first test match.
Quick to capitalise on the situation and curry favour with Australia's
sports-minded public, the food giant Heinz gained tremendous publicity
by its response to the starving cricketers. Team physiotherapist Errol
Alcott had sent a fax to the Australian Cricket Board requesting supplies
of suitable bland foods for Shane Warne who was unwilling to tackle the
locally made dishes in the team's posh hotel, the Taj Coromandel. Heinz
acted fast, shipping out a complimentary consignment of baked beans and
spaghetti for Warne and his team-mates - so that some of them had the opportunity
to breakfast on baked beans before taking the field on the fourth day of
the first test match in Chennai.
The action gave a whole new meaning to the phrase Food Aid to the Third
World - and seems to have generated more publicity in Australia than the
Berlin air lift.
The Australian cricketers' predicament serves to draw attention to a
basic question affecting many first time visitors to the Indian sub-continent.
Call it what you will - the Runs, the Trots, a Delhi belly or even that
delightful Sri Lankan phrase, "the stomach is going" - why is
it that an episode of diarrhoea becomes an almost inevitable consequence
of a tourist's passage to India? I have myself suffered on my visits to
the subcontinent - and I have wondered on these occasions: How can a visitor
enjoy Indian curries made-in-lndia and avoid suffering the after effects?
My old friend Dennis (himself a former national cricketer) used to say~
"The food they give you in India tastes fantastic - but while it makes
your taste buds sing and your heart beat faster, it also makes your stomach
go."
This "going stomach" is a major problem which can detract
from the visitor's enjoyment of Indian dishes.
The problem is best described in the words used by some Indian wags,
which though employed in a different context, aptly sum up what happens
when tourists consume too much curry in a hurry.
During the Chennai test match, when the Indian batsmen were thrashing
the Aussie bowlers, there appeared in the stands a hand-written banner
held aloft by some spectators.
In large red letters, large enough to be seen on TV screens across the
world, the banner proudly proclaimed this home truth: CURRY EATERS ALWAYS
GET THE RUNS.
Now I wonder whether eating beans will be effective in reducing the
visitors' Runs rate?
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