Malaria and Other Public Health Threats in the Republic of Korea

Korea is a key operational theater for U.S. forces.

chemoprophylaxis at a major cost savings to the

The range of emerging or potentially emerging disease

health care system. A traditional challenge to military

threats is wide and includes malaria, hantavirus infec 

malaria control has been failure to employ personal

tions, leptospirosis, Japanese encephalitis, scrub typhus,

prevention measures (PPM) effectively.  To document

murine typhus, and sexually transmitted diseases.  Due

the current level of soldier knowledge, attitudes, and

to the size of the U.S. military presence, the need for

behavior concerning PPMs, a questionnaire was

maximal military readiness, and this spectrum of

developed for the 2001 malaria season.  Data analysis

disease threats, DoD GEIS has made a specific

is pending, but it appears that troops continue to show

commitment to provide the 18th MEDCOM with

deficiencies with regard to the use of PPMs.  

resources to support activities that go beyond the

standard military medical surveillance program.

With respect to environmental surveillance for the

During FY 2001 initiatives focused on development

Japanese encephalitis threat, during FY 2001 4,300

of an integrated malaria and Japanese encephalitis

Culex tritaeniorhynchus mosquitoes collected during

vector surveillance system, rodent borne disease

2000 were analyzed, and 12 (1/357) carried the

surveillance for areas of high risk, and tick borne

Japanese encephalitis virus.  This is of concern as

disease surveillance to support risk analysis and iden 

the mosquitoes were collected within 0.5 km of Camp

tify potential human threats.  Close collaborations with

Greaves and less than 2 km from the Joint Security

Korean governmental and academic institutions have

Area (Camp Bonifas).  Considering the potentially

been cultivated over the last several years and are

devastating human effects of Japanese encephalitis,

helping DoD GEIS obtain valuable current incidence

the implications of this for expanded vector surveil 

data on Korean military and civilian populations.

lance, human serosurveillance, and possible immu 

nization need to be defined further.

The explosive re emergence of malaria in South

Korea during the 1990s, especially along the DMZ

DoD GEIS also helped to support the evaluation of

where many U.S. forces rotate, has made the careful

rodents around military encampments for infection

epidemiologic documentation of patterns in civilians,

with hantaviruses and scrub typhus.  Findings were

Korean military, and U.S. military important.  GEIS 

quite variable by region but worthy of close attention.

supported partners at the 18th MEDCOM have done

Two human cases of hemorrhagic fever with renal

this, documenting not only the continuing high rates but

syndrome occurred in U.S. forces in 2000, one of

also the use of chemoprophylaxis, the characteristics

these at Dagmar North and the other from Firing

of vector populations, and rainfall correlates.  The

Point 131 A.  The rodent surveillance showed that the

Armed Forces Research Institute of Medical Sciences

hantavirus infection rate exceeded 60% at Dagmar

(AFRIMS) supported these efforts during FY 2001

North and that it was 25% at FP 131 A.  During FY

by ELISA testing of more than 25,000 mosquito

2001, over 60% of Apodemus agrarius field mice

specimens for the presence of malaria, mostly from

collected at FP 131 A were positive for hantavirus

FY 2000 collections near Camp Greaves.  Interestingly

infection.  Further data collection is underway to

all the mosquitoes tested were negative for malaria.

permit trend analysis and predictions, but it appears

CHPPM Japan is providing analysis for mosquitoes

that many training areas should be considered high 

collected in FY 2001.  The 18th MEDCOM has used

risk during at least part of the year.  Other rodent

the malaria surveillance data to decide that only per 

surveillance studies are documenting notable rates of

sons residing north of the Imjin River will be placed

DNA positivity for the agents of human ehrlichiosis.  

on chemoprophylaxis, thereby limiting the use of

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