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We are reporting the first known isolation of the Q-fever agent Coxiella burnetii from field-collected cayenne ticks Amblyomma cajennense in North America. Q-fever affects a number of domestic ungulates where it can lead to abortion in sheep and goats. There is far less known about the disease's effects on wild species, primarily because of the tendency of the disease to self resolve and to provide long-term immunity to subsequent infections. The first recovery of C. burnetii in North America was from the tick species Dermacentor andersoni. Since the original isolation C. burnetii has been recovered from five other North American tick species. The currently accepted mode for the majority of human infections is inhalation. The Centers for Disease Control and Prevention, Division of Viral and Rickettsial Diseases, Rickettsial Zoonoses Branch asserts the Q-fever agent as requiring as few as one organism to cause disease via inhalation in susceptible humans. However, with more and more isolations from ticks, evidence linking C. burnetii and ticks is mounting. The true role of tick species as competent vectors is still unconfirmed. Preemptive field collections of possible vector arthropods, hosts, and reservoirs can provide invaluable baseline environmental data that will prove supportive in follow-up studies and abatement efforts., Prepared in cooperation with the Air Force Institute of Technology Civilian Institute Program, Texas A&M University, Department of Entomology, College Station.

CDC miniature light traps were used to evaluate the general biology of phlebotomine sand flies from April 2003 to November 2004 at Tallil Air Base, Iraq. Factors evaluated include species diversity and temporal (daily and seasonal) and geographic distribution of the sand flies. In addition, the abundance of sand flies inside and outside tents and buildings was observed. In total, 61,630 sand flies were collected during 1,174 trap nights (mean 52 per trap, range 0-1,161), with 90% of traps containing sand flies. Sand fly numbers were low in April, rose through May, were highest from mid-June to early September, and dropped rapidly in late September and October. More than 70% of the sand flies were female, and of these sand flies, 8% contained visible blood. Phlebotomus alexandri Sinton, Phlebotomus papatasi Scopoli, Phlebotomus sergenti Parrot, and Sergentomyia spp. accounted for 30, 24, 1, and 45% of the sand flies that were identified, respectively. P. alexandri was more abundant earlier in the season (April and May) than P. papatasi, whereas P. papatasi predominated later in the season (August and September). Studies on the nocturnal activity of sand flies indicated that they were most active early in the evening during the cooler months, whereas they were more active in the middle of the night during the hotter months. Light traps placed inside tents with and without air conditioners collected 83 and 70% fewer sand flies, respectively, than did light traps placed outside the tents. The implications of these findings to Leishmania transmission in the vicinity of Tallil Air Base are discussed., See also ADA497788, Part 1. Published in Journal of Medical Entomology, v44 n1 p29-41, Jan 2007.

One of the most significant modern day efforts to prevent and control an arthropod-borne disease during a military deployment occurred when a team of U.S. military entomologists led efforts to characterize, prevent, and control leishmaniasis at Tallil Air Base (TAB), Iraq, during Operation Iraqi Freedom. Soon after arriving at TAB on 22 March 2003, military entomologists determined that 1) high numbers of sand flies were present at TAB, 2) individual soldiers were receiving many sand fly bites in a single night, and 3) Leishmania parasites were present in 1.5% of the female sand flies as determined using a real-time (fluorogenic) Leishmania-generic polymerase chain reaction assay. The rapid determination that leishmaniasis was a specific threat in this area allowed for the establishment of a comprehensive Leishmaniasis Control Program (LCP) over 5 mo before the first case of leishmaniasis was confirmed in a U.S. soldier deployed to Iraq. The LCP had four components: 1) risk assessment, 2) enhancement of use of personal protective measures by all personnel at TAB, 3) vector and reservoir control, and 4) education of military personnel about sand flies and leishmaniasis. The establishment of the LCP at TAB before the onset of any human disease conclusively demonstrated that entomologists can play a critical role during military deployments., See also ADA497789, Part 2. Published in Journal of Medical Entomology, v43 n4 p647-662, Jul 2006.

Visceral leishmaniasis (VL) is a potentially fatal disease caused primarily by Leishmania donovani complex species in Old World endemic regions. Pathogenesis requires a virulent factor transcribed by a gene family designated A2. An A2 sequence specific fluorogenic probe hydrolysis (TaqMan) PCR assay was developed on a field-deployable assay platform for real-time screening of the sand fly vector for VL causative agents. Laboratory-based assay optimization and specificity testing were conducted with total nucleic acid extracted from L. donovani-infected Phlebotomus alexandri, the primary vector. Cross-reactivity did not occur when tested against total nucleic acid extract of L. tropica-infected P. sergenti, L. major-infected P. papatasi, clinically relevant organisms, diverse viral and bacterial species, vector and human genomic DNA. Field evaluations were conducted in south central Iraq with sand fly pools screened by a previously established Leishmania universal PCR assay. The Leishmania universal assay was field-formatted (lyophilized) prior to deploying and upon field-evaluation against cold chain maintained wet reagents results were 98% (55/56) concordant. Of 86 Leishmania-positive sand fly pools, six were identified as A2 positive with a field-formatted visceral genotype specific assay., See also ADM001747, RTO-MP-HFM-108. Presented at the RTO Human Factors in Medicine Symposium on "NATO Medical Surveillance and Response, Research and Technology Opportunities and Options," held in Budapest, Hungary on 19-21 Apr 2004. Prepared in cooperation with Air Force Institute for Operational Health (AFIOH), Brooks AFB, San Antonio, TX, and U.S. Army Medical Research Institute for Infectious Disease (USAMRIID), Fort Detrick, Frederick, MD. The original document contains color images.

An Aedes aegypti specific fluorogenic probe hydrolysis (TaqMan) PCR assay was developed for real-time screening using a field-deployable thermocycler. Laboratory-based testing of Ae. aegypti, Ae. aegypti (Trinidad strain); Culex pipiens; Culex pipiens quinquefasciatus; Anopheles stephensi; Ochlerotatus taeniorhynchus individual adult mosquitoes and mixed pools (n=10) demonstrated 100% concordance in both in vitro sensitivity (6/6) and specificity (10/10). A single adult Aedes aegypti was identified in a pool of 100 non-Aedes aegypti mosquitoes. The limit of detection of Aedes aegypti egg pools was 5 individual eggs. Field-testing was conducted in central Honduras. An Aedes aegypti and Culex spp. panel of individual and mixed pools (n = 30) of adult mosquitoes, pupae, and larvae demonstrated 100% concordance in sensitivity (22/22) and 97% concordance in specificity (29/30) with one false positive. Field-testing of an Aedes aegypti and Culex spp. blind panel (n = 16) consisting of individual and mixed pools of adult mosquitoes, pupae, and larvae demonstrated 90% concordance in sensitivity (9/10) and 88% concordance in specificity (14/16)., See also ADM001747, RTO-MP-HFM-108. Presented at the RTO Human Factors in Medicine Symposium on "NATO Medical Surveillance and Response, Research and Technology Opportunities and Options," held in Budapest, Hungary on 19-21 Apr 2004. Prepared in cooperation with Air Force Institute for Operational Health (AFIOH), Brooks AFB, San Antonio, TX; USAF Force Protection Battlelab, Lackland AFB, San Antonio, TX; USAF School of Aerospace Medicine, Brooks AFB, San Antonio, TX; U.S. Army Medical Research Institute for Infectious Disease, Fort Detrick, Frederick, MD; U.S. Army Center for Health Promotion