Biology Reference
In-Depth Information
5. SURVEILLANCE AS KEY INTERVENTION FOR
MALARIA ELIMINATION
One of the greatest differences between a malaria control program and
elimination is the degree of epidemiological surveillance required (
Moonen
et al., 2010
). If one can identify persons with parasites, then the parasites can
be eliminated, but identification of those persons can be difficult especially
with vivax hypnozoites (
Kaiser, 1966
). As malaria cases become fewer, more
effort is required to find them. Surveillance and its degree of completeness
must increase as one progresses from a control program to elimination. Sur-
veillance must be seen as a key intervention that distinguishes elimination
from malaria control.
5.1. Korea
South Korea was certified malaria free by the WHO in 1985. In the early
1990s, indigenous vivax malaria cases began to reappear in both Korean
and US soldiers stationed in the Demilitarized Zone on the border with
North Korea (
Park et al., 2009
;
Klein et al., 2009
;
Jun et al., 2009
). By 2000,
4142 cases (all vivax) were reported and transmission had expanded from
a border problem to involve many other areas of South Korea (
Kim et al.,
2009
). Chemoprophylaxis with chloroquine was done initially in 16,000
South Korean soldiers during 1997 and then increasing to 200,000 soldiers
in 2005 with decline in case numbers; unfortunately, it was very difficult to
obtain compliance with primaquine eradication courses following the sol-
diers, release from military service (
Yeom et al., 2005
). Vivax relapses often
occurred in ex-soldiers following their disbursement throughout the civil-
ian population of South Korea, especially given the tendency for Korean
vivax to relapse the year following initial infection. Climate restricts vivax
malaria transmission to the months of June to September in Korea. Follow-
ing reduction of annual cases to <1000 in 2004, cases have again increased
above 2000 in 2007 (
Park et al., 2009
). Surveillance and detailed geo-
graphic tracking of vivax malaria cases in Korea has been done with hopes
of returning to the pre-1990 situation of no malaria (
Choi et al., 2010
).
Malaria elimination target date is now 2015 but 1317 cases were reported
in 2009 indicating a great deal of work remains in order to interrupt trans-
mission. Given the unclear situation in North Korea and the inability to do
any antimalarial activities in the Demilitarized Zone, careful case finding
coupled with complete primaquine treatment seems to be the main course
of action for South Korea.
