Vector-borne Disease Surveillance in Southeast Asia – Challenges and Opportunities in Vector Collection and Pathogen Detection MAJ Brian Evans, Ph.D.; Jim McAvin; Alongkot Ponlawat, PhD; Ratree Takhampunya, PhD; LTC Jason Richardson, PhD . Mission Intelligence requirements
Vector-borne Disease Surveillance in Southeast Asia –
Challenges and Opportunities in Vector Collection and
MAJ Brian Evans, Ph.D.; Jim McAvin; Alongkot Ponlawat, PhD; Ratree
Takhampunya, PhD; LTC Jason Richardson, PhD
PM detachment capabilities
Detection capabilities (JBAIDS)
Value of pathogen assays
Where is the gap?
To accurately asses the risk of vector-borne disease in an AO and to recommend/ implement measures that reduce the disease threat among soldiers.
Human case data
Vector data (presence/absence)
Pathogen data (presence/absence)
Gather case data (non-specific/specific)
Limited vector surveillance
Limited or no pathogen detection capability.
Case data is specific in number and location.
Vector surveillance, pathogen detection tools, and control tools are effective.
Adult mosquito/sand fly collection devices minimally effective; taxonomic keys
1 or 2 Ae. aegypti /house (15 mins/house); countless man-hours and houses needed for sufficient sample sizes (1 in 1000 infected); this is an area where there is transmission of dengue year-round.
BG Sentinel (BG Lure)
Bed net trap - NAMRU-2
Rodent-baited traps as a tool for collecting chigger mites, vectors of scrub typhus.
Figure 13: Field caught rodent on snap trap
Figure 4: Rodent with chiggers
Low densities; seasonality?
How does pathogen/vector data translate into risk?
What does it mean to have 6 in 1000 infected; should I be concerned?
Even when we know the vector locations and where the pathogen is most prevalent in the vector, do we understand the biology?
Not one-size fits all solutions; same species from different locations may have evolved independently; different vector ecology
Bottom-line: Pathogen detection has greatest added value for risk determination and control efficacy in instances where there is limited or no case data. If disease is seasonal, a valuable forecasting tool.
Challenge: Relevancy of pathogen detection data is highly-dependent on the vector surveillance tool.
Pathogen surveillance should be a critical part of the PM mission; need more effective surveillance tools to complement this mission; need trained soldiers who can interpret information/data.
Where time/resources/money are limited, should be very selective about when and where to use pathogen detection assays.