Malaria still remains a major public health problem
worldwide, particularly in tropics such as developing
countries in Southeast Asia[1]. With frequent outbreak, 687
million people in this region are at high risk for malaria.
The disease affects all age groups and causes over 120 000
deaths each year[1]. In addition, resistance to common
antimalarials is emerging faster in Southeast Asia than
in any other part of the world, resulting in the declining
efficacy of chemotherapy[2-4]. Due to a severe and disastrous
economic impact of malaria, besides its health impact, the
WHO Regional Office for Southeast Asia call for an urgent
attention from the policy-maker at the national level for
malaria control[5].
Currently, mass migrations of foreign workers to Thailand
from high endemic areas, mainly Myanmar, may enhance
risk of malaria transmission[6-8]. Although registered
foreign workers have to receive a health-screening
program for communicable diseases (i.e., tuberculosis,
leprosy, elephantiasis, and syphilis, malaria infections do
not include in this health assessment[7]. In order to set up
better and more effective interventions for malaria control,
a significant epidemiological data are needed. Therefore,
this study aimed to determine the prevalence of malaria
infections among foreign workers by using microscopic
examination on thin and thick blood films. Additionally a
preliminary observation focusing on RBC morphology and
differentiation of white blood cells were undertaken for
screening of health status among foreign workers.