Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/20/2002
Publication Date: 9/20/2002
Citation: Herrero, M.V., Schmidtmann, E.T., Craig, M.E., English, M. 2002. Sampling for sand flies (Diptera: Psychodidae) on ranches with histories of vesicular stomatitis disease in New Mexico and Colorado. Journal of Medical Entomology. 39(4): 680-684.
Interpretive Summary: We investigated the possible presence of a sand fly associated with prairie dogs on six ranches with histories of vesicular stomatitis (VS) disease in the mid-Rio Grande river valley of New Mexico and West-slope region of Colorado. Vesicular stomatitis disease affects horses and cattle in the southwestern U.S., and because the lesions that develop in the mouth mimic foot and mouth disease, quarantines and restrictions are placed on the movement of infected animals. Outbreaks of VS, which occurred in 1982-3, 1995, 1997 and 1998, occur at sporadic intervals. This study was conducted because sand flies are known vectors and reservoirs of VS virus in other areas of the U.S. and Central America, but have not been detected in studies of insects during outbreaks of VS in the southwestern U.S. We used several types of traps at each location that were set out bi-weekly from April to July 2000. We captured two male and four female sand flies, Lutzomyia apache, on a cattle ranch in Socorro County, New Mexico. All other locations were negative. This finding is of interest because sand flies have not been reported from the Rio Grande river valley, this area has been a "hot spot" of VS disease during recent outbreaks, and the source of VS viruses in the southwestern U.S. is unknown, but may involve introduction of virus from Mexico or a cycle in the U.S. maintained by vector insects.
Technical Abstract: The possible presence of sand flies (Diptera: Psychodidae) among colonies of white-tailed prairie dogs, Cynomys gunnisoni Baird, was investigated on or near ranches with histories of vesicular stomatitis (VS) in domestic livestock in the mid-Rio Grande River Valley, New Mexico and West-slope region of Colorado. Sampling was conducted at six premises, three in each region, using three methods; standard down-draft suction/light traps, up-draft suction/light traps (both supplemented with CO2), and burrow-emergence traps. Two male and four female sand flies, Lutzomyia apache, were recovered from prairie dog colony and sand- sagebrush association habitats on a cattle ranch in Socorro County, New Mexico. Sand flies were captured only in up-draft suction/light traps. This record is of interest because: 1) sand flies have not been reported from the Rio Grande River Valley of New Mexico, 2) sand flies are biological vectors of VS viruses in other areas, 3) the mid-Rio Grande River Valley has been a focus of VS virus activity in domestic livestock during recent outbreaks, and 4) the source of vesicular stomatitis viruses that infect livestock in the western U.S. is unknown, but may involve introductions of virus from Mexico or an endemic cycle maintained by vector insects.