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BACKGROUND
The Situation
Refugees:
There are more than 100,000 Karen, Mon, Karenni ethnic minority living
in a string of refugee camps along the Thai-Burmese border. This area
is endemic for malaria transmission which results in symptomatic infection
in all age groups. In Shoklo camp the attack rate was 3 episodes per person
per year for the potentially fatal P.falciparum parasite (which accounts
for approximately 70% of infections). P.vivax accounts for 20% of cases,
the remaining being mixed PF/PV. The most important medical problem confronting
the refugee community is the increasing anti-malarial drug resistance.
The main consequence of the deterioration of treatment efficacy is anaemia.
Children are particularly susceptible to malaria induced anaemia. In 1992
mortality from malaria accounted for 15% of all deaths in the camps. Between
1995 and 2000 the burden of malaria has fallen dramatically in the refugee
camps has a result of the strategy designed at SMRU and used by all medical
NGOs.
The migrants:
In recent years the population influx from Myanmar has increased dramatically
for both economic and political reasons. People from all ethnic groups
(Shan, Karenni, Karen, Mon and Burman) are travelling back and forth across
the border in search of work. It is thought that this population of migrant
workers totals more than one million people in Thailand. Unlike refugees,
they are highly mobile, and the majority does not have access to basic
health care. Collectively, they harbour the majority of Thailand's malaria
cases. This population of migrant workers, especially those living in
the border areas, constitutes a major challenge to the control of malaria
in the region and is now probably the major factor contributing to the
spread of resistant strains of malaria. As they have done before, these
strains will spread to the host population, the entire region, and later
to other parts of the world. Given the paucity of new drugs against malaria
this apparently local problem takes on a global dimension. Untreatable
malaria infections would be a major threat to anyone living in or travelling
to endemic areas. The “border population” can be seen as a
mosaic of various communities linked by cultural and/or geographical similarities:
Thai nationals (the majority is ethnic Karen), refugees and migrant workers
from Myanmar. This complicates the task of the Thai Malaria Control programme
because of language barriers, cultural differences and access difficulties.
As a result, many individuals remain out of reach of the otherwise highly
efficient malaria control efforts. SMRU has initiated novel approach for
an effective malaria control programme in the populations living along
the Thai-Myanmar border, through existing and new medical facilities,
based on extensive experience with the displaced populations living in
camps in this area.
This malaria research and control project differs from nearly all others
in that it proposes to evaluate and deploy a strategy based on evidence
acquired in the region, rather than on principles developed elsewhere
or empirically. Since 1986 an operational research programme, initiated
in response to the alarming rise in antimalarial drug resistance, has
guided the malaria control programs of the various NGOs provided health
services to the displaced populations in refugee camps along the Thai
Myanmar border. This programme was (and still is) part of the Wellcome-Mahidol
University-Oxford Tropical Medicine Research Programme based in the Faculty
of Tropical Medicine, Mahidol University, Bangkok, Thailand. It has focused
on the epidemiology, the treatment and the prevention of falciparum malaria
in the populations living in camps along the border. The main achievements
of this programme and the deployment by all medical NGOs of the strategy
elaborated were:
- The very significant reduction (over 90%) in the incidence of P.falciparum
infections in the camps.
- The reduction in morbidity and mortality due to malaria and in particular
the maternal mortality.
- The halt to the hitherto rapid increase in drug-resistance.
These results are explained by the combined effects of Early Detection
and Treatment (EDT) and the use of the artesunate-mefloquine combination
treatment (for more details see our web site). This led directly to a
global programme to evaluate and deploy antimalarial drug combinations
throughout the tropical world, and illustrates the pivotal role of operational
research in guiding malaria control activities. This dramatic effect on
malaria was seen in all the camps where this approach was deployed but
not initially in communities outside the camps, where the same strategy
was not deployed. This experience demonstrates that it is possible to
control malaria and the spread of resistance with the judicious use of
EDT and combination therapy. But would this work outside the well controlled
context of refugee camps? In 1998 and 1999 malaria surveys were conducted
in the Thai-Karen villages in the surroundings of Maela camp and also
in settlements of migrant workers south of Mae Sot. High prevalence rates
of malaria were found in some villages especially in Pho Prah district,
south of Mae Sot. Two clinics were set up in collaboration with the Thai
Public Health Office: in Mawker Thai and Munruchai. Since then the clinics
have treated over 4000 patients with confirmed falciparum malaria (Thai
nationals as well as migrants), established a weekly consultation for
pregnant women (identical to the screening in the camps) and followed
malaria patients to ensure compliance to the treatment.
Shoklo Malaria Research Unit (SMRU)
The SMRU is attached to the Hospital of Tropical Medicine, Mahidol University,
Bangkok which provides scientific, administrative and logistical support.
There is an office in Mae Sod which provides the logistical support and
has two laboratories. In Maela there are hospital, laboratory, obstetric
unit, outpatients department, ante and post-natal clinic, computing area
and staff accommodation. Advanced training has been provided over the
years so that today, highly competent Karen staff are operating the Unit.
In Maela camp, three clinics, an office and staff housing have been built
in 1995-6. Maela has become the centre for SMRU operations in the camps.
Mae Sot base, the vehicles and Maela Unit are linked by radio. One hour
drive to the south of Mae Sot SMRU has opened 2 clinics for migrant workers:
Mawker Tai and Muruchai. These 2 clinics serve a population of 15-20,000.
The importance of malaria, the size and stability of the population, the
ability to follow the patient’s progress and the excellent co-operation
of the community make the site an ideal place to study malaria. Since
1986 over 10,000 people have been enrolled in more than 18 studies with
excellent compliance (over 90% patients attending follow up assessments). |