Sand Flies (Diptera: Psychodidae: Phlebotominae): Significance, Surveillance, and Control in Contingency Operations

Sand flies belong to the subfamily Phlebotominae of the dipteran family Psychodidae. Sand flies are small, with a body about 3mm in length being typical for many species. They are noted for hairy bodies and wings and relatively long legs. At rest, the wings are held nearly erect and in a characteristic upright V-formation, unlike most other biting flies. Sand flies have nearly silent flight Killick-Kendrick 1999, Maroli et al. 2012, presumably from the presence of hairs on their wings, which in combination with their small size, may explain their ability to inflict multiple bites on humans and remain undetected. Only females are able to pierce the skin of their vertebrate hosts to imbibe blood. Although not always felt, sand fly bites usually produce small, round, reddish bumps that may start itching hours or days later. Some species are selective in their feeding habits, but others feed on any suitable animal they encounter. They use their mouthparts to lacerate the host s skin, disrupting cells and causing a blood pool to form, from which they obtain their blood meal. Like most blood-feeding ectoparasites, they inject salivary proteins and other biochemicals into the bite wound, which then serve to inhibit blood clotting and promote blood flow. In addition to being a tremendous nuisance when their biting interferes with and degrades mission performance, sand flies have been implicated as vectors of several disease agents, including those responsible for the various forms of leishmaniasis. Sand flies have been, and will continue to be, a major preventive medicine issue during military exercises and operations conducted within their geographic range. For these reasons, sand fly surveillance and control are key responsibilities of utmost importance for preventive medicine personnel. Control of sand flies can be difficult because immature habitats are poorly understood, which makes them difficult to target with available control measures.