Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: VECTOR COMPETENCE AND PROTECTION OF U.S. LIVESTOCK AND WILDLIFE FROM ARTHROPOD-BORNE DISEASES
2005 Annual Report


1.What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter?
This is the annual report for the new OSQR-approved project, 5410-32000-014-00D, that replaces a related project, 5410-32000-014-00D (see separate annual report terminating that project). Blood-feeding insects such as biting midges and mosquitoes are efficient vectors of viruses that cause diseases with significant economic impacts on livestock industries and public health. Bluetongue, epizootic hemorrhagic disease, and vesicular stomatitis viruses account for acute and chronic health problems, as well as production-related losses among U.S. livestock. Also of concern in the global economy of the 21st Century, these diseases trigger quarantine and non-tariff trade barrier restrictions that limit animal movement and export sales of U.S. livestock and their germplasm. U.S. agriculture is likewise highly vulnerable to exotic arthropod-borne animal pathogens. Outbreaks of endemic, emerging, and exotic insect-transmitted viruses have potential to cause very serious disease problems for livestock populations; losses from some viruses if introducted would be catastrophic. The rapid spread of recently introduced West Nile virus (WNV) in North America illustrates clearly the rapid, uncontrolled spread, and public/veterinary health impacts of an exotic arbovirus, as well the critical need for improved surveillance and vector control. Among other pathogens with potential for invading the U.S., Rift Valley fever, exotic bluetongue and epizootic hemorrhagic disease, vesicular stomatitis, African horse sickness, and akabane viruses are of particular concern. Thus it is all too apparent that the accidental or intentional (bioterrorist) introduction of arthropod-borne pathogens from other regions of the World would have potential for damaging impacts on U.S. livestock commodities and public health. The key role that insects play as vectors of viral pathogens results from the fact that:.
1)blood-feeding insects are the primary means by which host animals are infected with arboviruses in nature;.
2)vector insects represent a source of virus amplification and maintenance in time and space; and.
3)insect blood-feeding activity defines the seasonal incidence and geographical distribution of risk for host exposure. This research is conducted under National Program NP104: Arthropod Pests of Animals and Humans. Research conducted under this CRIS project benefits U.S. agriculture by providing a better understanding of:.
1)the molecular mechanisms that regulate the competence of insects that transmit pathogenic viruses,.
2)the role of environmental factors as they influence vector population distribution and vector competence, and.
3)the possible role of insects in the maintenance and spread of prion proteins. Proposed research is optimized by the availability of recent molecular approaches and computer-aided data processing and analysis methods that provide insights and capabilities previously unavailable. Research herein also contributes to the development of novel strategies for controlling insect vector species and their competence in transmitting pathogens, as well providing a data for scientifically-based domestic and international trade regulations that protect U.S. livestock from the continuous threat of indigenous, exotic, and emerging insect-borne diseases. This research is relevant to all aspects of the U.S. economy that have interests in and are affected by the health of U.S. livestock, collectively strengthening the rural economy, providing a continued supply of inexpensive, wholesome food products for the American consumer, diminishing disease risk to human and animal populations, as well as promoting the profitability and international competitiveness of livestock products.


2.List the milestones (indicators of progress) from your Project Plan.
12 month Milestone(s). Objective 1 1a. No milestone. 1b. No milestone. 1c. The possibility of mechanical transmission of VSV by Culicoides will be determined. 1d. A colony of C. sonorensis refractory to infection with BTV will be established. 1e. Develop diagnostic assays (for prions). Objective 2 GIS analysis of environmental factors associated with positive and negative sites for C. sonorensis will be completed and manuscript prepared for publication in the Journal of Medical Entomology. Objective 3 3a. Specificities of examining Culicoides salivary gland and midgut proteins by 2D electrophoresis will be determined. 3b-1. Public release of the midgut and salivary gland EST datatbase to dBEST. 3b-2 Further characterization of the genes that are affected by virus infection will be done. 3b-3. The ABADRL insectary will be expanded to rear and conduct research on vector mosquitoes. 3b-4. RNA inhibition technology in mosquitoees will be transferred to ABADRL. 24 month Milestone(s) Objective 1 1a. No milestone. 1b. No milestone. 1c. No milestone. 1d. A colony of C. variipennis refractory to infection with BTV will be established. 1e. Develop diagnostic assays and test insects treated with prions. Objective 2 2a. No milestone. Objective 3 3a. Specific salivary gland proteins expressed in response to feeding will be determined and sent for spectral analysis. The effects of Culicoides saliva on VSV infection in cattle skin will be determined. 3b-1. Manuscript describing the consensus midgut and salivary gland cDNA sequences and compiled gene ontologies will be published. 3b-2. Initial study comparing sequence variation and gene expression of suspected vector competence genes in Culicoides-competent and not-competent in BTV transmission will be published. 3b-3. RNA inhibition technologies in mosquitoes will be adapted to Culicoides. 3b-4. The Culcoides' receptor for bluetongue virus will be further characterized. 36 month Milestone(s) Objective 1 1a. First season field sampling for the sand fly Lutzomyia apache in southern New Mexico will be conducted. 1b. No milestone. 1c. The rate of horizontal transmission of VSV by Culicoides in deer mice will be determined. 1d. No milestone. 1e. Survey trapped insects. Conduct experiments on transmission of prions using insects. Objective 2 GIS analysis of environmental factors associated with Culex tarsalis and coal bed methane impoundments will be completed and a manuscript prepared for publication in the Journal of Medical Entomology. Objective 3 3a No milestone. 3b 1 Genetic studies of suspected vector competence genes in exotic species of Culicoides will be published. 3b 2 RNA inhibition studies on suspected vector competence genes on the infection of Culicoides spp. will be published. 3b 3 Strategies to block bluetongue virus infection of Culicoides at the receptor level will be examined and the results published.

48 month Milestone(s) Objective 1 1a Second season field sampling for the sand fly L. apache in southern New Mexico will be conducted. 1b No milestone. 1c The rate of vertical transmission of VSV (in Culiccoids sonorensis) as determined by virus isolation in eggs of infected adults will be determined. 1d No milestone. 1e Determination of vertical transmission of prions in insects. Objective 2 The effects of selected environmental factors on infection of BTV in C. sonorensis will be conducted. Objective 3 3a Immunomodulatory salivary proteins will be cloned and expressed. Expressed mmunomodulatory salivary proteins will be examined for their effects on virus infection. 3b Continued genetic studies of suspected vector competence genes to exotic species of Culicoides will identify species-specific genetic markers and potential vector competence genetic markers.


4a.What was the single most significant accomplishment this past year?
Gene sequences determined and made available to the public.

An EST database of genes expressed in the salivary glands and midguts of C. sonorensis has been published and is available through GenBank. Salivary glands and midguts express genes that could be related to vector competence and this information is being used in current research described in a related CRIS project. The results of this research provide a foundation for research to identify vector competence genes, as well as new strategies for targeted control of arboviral disease transmission systems. The ABADRL has received two requests for international collaborations as a result of this work.


4b.List other significant accomplishments, if any.
Lab study shows biting midge susceptible to infection with virus.

Culicoides sonorensis was shown to be a biologically competent vector for vesicular stomatitis virus (VSV). Virus passed efficiently through the midgut and salivary gland barriers and replicated throughout the insect. Virus replication and production was detected in salivary glands from days 3-13 post feeding and in the eggs from days 5-13. This is the first report of the vector competence of Culicoides for VSV.


4c.List any significant activities that support special target populations.
None.


4d.Progress report.
5410-32000-014-02T. This report serves to document research conducted under Trust Agreement 58-5410-3-0019, "Effects of temperature on vector competence of the biting midge, Culicoides sonorensis, for bluetongue virus" with the ARS and Agriculture Canada. Because of concern over the potential risk for transmission of bluetongue virus in cattle exported from Montana to Alberta, field populations of the primary vector of bluetongue virus, C. sonorensis from northern Montana and Alberta are being challenged with bluetongue virus as a test of their oral susceptbility, a key component of vector competence. The 2003 study demonstrated that only one of 75 female C. sonorensis from Alberta, Canada challenged with bluetongue virus and incubated for 12 days at 20 degrees Centigrade was positive for bluetongue virus. Of 121 female C. sonorensis from Malta, Montana and challenged with bluetongue virus, no (0) females became infected. Flies challenged in 2004 and 2005 were held for 12 days at 22 degrees Centigrade to test the effects of higher temperature on virogenesis. These flies will be assayed for infection in September, 2005. The data available to date suggest that the populations from which the test flies were collected in Alberta and northern Montana are refractory (non-susceptible) to infection with bluetongue virus. If confirmed by 2004 and 2005 study, the data will support reduced testing of Montana cattle for bluetongue virus before export to Alberta feedlots.

5410-32000-014-01R. This report serves to document research conducted under Reimbursible Agreement #60-0200-5-2004, "Deployed Warfighter Protection Research Program", between ARS and the U.S. Department of Defense. Plans for a new insectary that will be used to culture insect species of interest to DOD have been completed and a construction contract awarded. New species of insects that will be colonized at the new insectary are as follows..
1)Mosquito, Aedes vexans, predicted to be a primary vector of Rift Valley Fever virus if introduced into North America..
2)Mosquito, Culex tarsalis, vector of West Nile virus and putative vector of Rift Valley Fever virus in the western U.S..
3)Biting midge, Culicoides paraensis, vector of Oropouche virus among U.S. military troops in South America. These species, along with current laboratory colony Culicoides sonorensis, will be used in studies that evaluate the behavioral and toxicological effects of synthetic pyrethroid compounds that have repellent activity, and thus potential for protecting troops (and livestock) from blood feeding of mosquito and biting midge vectors of pathogenic viruses, such as Rift Valley Fever virus. Lab colony insects also will used as appropriate in experimental transmission trials with attenuated vaccine viruses.

5410-32000-014-03N. This report serves to document research conducted under Non-Funded Cooperative Agreement #58-5410-4-106N, "Radioactive Materials License", between ARS and the University of Wyoming. During the first phase of this project the University of Wyoming oversaw the ABADRL radioactive materials safety program and held the NRC license utilized by ABADRL staff. ABADRL staff participated in the training and advising of University of Wyoming's students as adjunct appointees.

5410-32000-014-04N. This report serves to document research conducted under Non-Funded Cooperative Agreement #58-5410-4-104N, "Promote the Efficient and Safe Diagnosis and Surveillance of Emerging Arthropod-Borne Infectious Diseases in Wyoming", between ARS and the Wyoming Department of Health, Cheyenne, WY. Mosquito and biting midge populations were sampled across Wyoming and tested for infection with West Nile virus (WNV) to determine virus infection rates and the host source of blood meals. About 0.06-0.07% of mosquitoes (Culex tarsalis, C. pipiens, Aedes vexans, Psorophora sp., Culiseta inornata, Ochlerotatus dorsalis, O. melanimon, O. campestris, O. trivittatus) were positive for WNV; no Culicoides were found to be positive for WNV the virus (19,445 biting midges were tested). Mosquito blood meal analyses revealed deer, cattle, antelope, jack rabbit, sparrow, skunk, vole, duck, sage grouse, human, oriole, and owl as hosts for mosquito feeding.

5410-32000-014-05N. This report serves to document research conducted under Non-Funded Cooperative Agreement #58-5410-4-107N, "Evaluation of New Molecular Targets to Control Arbovirus Transmission", between ARS and the Colorado State University, Fort Collins, CO. During the first phase of this project ARS worked with the CSU Arthropod-borne Infectious Diseases Laboratory from May to August 2005 to learn the molecular tools for gene silencing. Two potential targets were identified and one was successfully cloned into a RNA transcription vector that was used to produce double-stranded (ds)RNA by vitro transcription. The dsRNA produced was injected into Aedes aegypti to produce small inhibitory RNA (siRNA). The ability of this mosquito RNA silencing system to affect the replication of a Malaysian Sindbis strain MRE16 that replicates in Aedes aegypti midgut cells was evaluated. Preliminary results suggest that the target successfully reduced virus dissemination from the midgut. This technology has been transferred to ABADRL and studies are being conducted to confirm the findings. Eventually, the technology will be adapted for use in Culicoides. Ultimately, the technology will be transferred to the field to confer resistance to bluetongue viruses on Culicoides spp.

5410-32000-014-06N. This report serves to document research conducted under Non-Funded Cooperative Agreement #58-5410-4-111N, "Detection of Arthropod-Borne Diseases and Protection of Livestock", between ARS and the Wyoming Department of Agriculture, Cheyenne, WY. ABADRL scientists developed a high throughput IR dye diagnostic method for detection of bluetongue virus (BTV) in Culicoides. Sensitivity of the method is 1 pfu from an extraction of 10 pfu's. All 24 BTV serotypes can be detected. Epizootic hemorrhagic disease virus serotypes are apparently not detected by this method.

ABADRL scientists sampled mosquito populations in high risk habitats of Wyoming and assayed for infection with bluetongue and West Nile virus (WNV) and the source of blood as evidence of blood feeding patterns associated with virus transmission. Mosquito blood meal analyses revealed deer, cattle, antelope, jack rabbit, sparrow, skunk, vole, duck, sage grouse, human, oriole, and owl as hosts. About 0.06-0.07% of mosquitoes (Culex tarsalis, C. pipiens, Aedes vexans, Psorophora sp., Culiseta inornata, Ochlerotatus dorsalis, O. melanimon, O. campestris, O. trivittatus) were positive for West Nile virus; no Culicoides sonorensis, the most common blood-feeding insect captured, were positive for WNV (19,445 tested). Of the ca. 22,000 C. sonorensis captured, 9,000 have been tested for the presence of Buetongue virus, none of which were positive.

5410-32000-014-07N. This report serves to document research conducted under Non-Funded Cooperative Agreement #58-5410-4-125N, "Research on Arthropod-Borne Diseases of Livestock and Wildlife and Their Vectors", between ARS and the University of Wyoming, College of Agriculture, Laramie, WY. Cooperative efforts with the University of Wyoming have shown that West Nile virus has had a serious impact on the Western sage grouse; this bird has very limited resistance to West Nile virus.

ARS Project 58-5410-3-0411. "Ecology of mosquito vectors of West Nile virus in the Rocky Mountain Region". This report serves to document research conducted under a Reimbursable Cooperative Agreement between ARS and the University of Wyoming. Little is known about the mosquito vectors of West Nile virus (WNV) in the inter-mountain West, or their role as risk factors for transmitting WNV among human, livestock, and wildlife populations. The objective of this research is to define the role of mosquitoes as vectors of WNV in the inter-mountain West based on patterns of distribution, abundance, virus infection rates, and sources of mosquito larval development in aquatic habitats. 2003 study documented high populations of the mosquito Culex tarsalis, an efficient vector of WNV, in both rural (agricultural) and urban (the city of Torrington, WY) areas of southwestern Wyoming. Abundant immature C. tarsalis were detected in flood irrigated agricultural cropland, particularly corn fields, which suggests that mosquitoes in Torrington were the result of dispersal from irrigated cropland.

A second study documented adult C. tarsalis associated with water impoundments created by extensive production of coal bed methane gas in an otherwise arid region of northcentral Wyoming (Powder River Basin). WNV was detected at a rate of 7.6 infected C. tarsalis per 1000 female specimens. The mosquitoes were captured from sites where an ecologically sensitive wildlife species, the greater sage grouse, suffered mortality from infection with WNV. More extensive study in 2004 and 2005 has confirmed the widespread occurrence of C. tarsalis in the Powder River basin, the infection of females with WNV, the presence of larval populations in coal bed methane ponds, and the blood feeding of C. tarsalis from avian hosts in the proximity of populations of sage grouse. These findings represent strong evidence that C. tarsalis in the primary vector of WNV in the sagebrush-steppe community where humans and ecologically sensitive wildlife populations are at risk for exposure.


5.Describe the major accomplishments over the life of the project, including their predicted or actual impact.
This research falls within National Program 104, components 1 (ecology and epidemiology), 3 (biology, physiology and vector - pathogen interaction), and 4 (control technology). The Strategic Plan goal addressed is Goal 3 - Enhance protection and safety of the Nation's agriculture and food supply, Objective 3.2 - develop and deliver science-based inforation and technolgies to reduce the number and severity of agriultural pest, insect, weed and disease outbreaks.

ABADRL field and laboratory research incrimiated the biting midge, Culicoides sonorensis, as the primary, proven vector of bluetongue viruses in the U. S. Data developed by the ABADRL also established that the northeastern U.S. is bluetongue-free because it is outside the range of C. sonorensis. An ABADRL extensive investigation of the population genetics of the C. variipennis complex in North America resulted in a taxonomic revision of the species complex, in which the three subspecies were elevated to species status. In follow-up study, it was demonstrated that levels and types of dissolved salts in larval habitats differ among aquatic habitats occupied by respective species. In a study to develop methods for assessing bluetongue disease-free regions in support of export sales for U.S. livestock, 74 farms and ranches across Nebraska, South and North Dakota were sampled for C. sonorensis, the primary vector of bluetongue viruses in the U.S. The results show that the presence of C. sonorensis populations is correlated with geographic regions where evaporation exceeds precipitation and soils are non-glaciated. This information will help to clarify the epidemiology of bluetongue in both enzootic and bluetongue-free regions, further illustrating that the presence of the vector C. sonorensis is a primary risk factor for the exposure of livestock to bluetongue viruses. These findings open the way for analysis of environmental factors that support the presence of C. sonorensis populations, as well as large scale mapping and prediction of C. sonorensis using computer-based GIS methods. The demonstration of bluetongue-free regions of the U.S. has resulted in a relaxation of export regulations, thus improving the competitiveness of U.S. livestock and livestock germplasm in world markets.

The role of C. sonorensis as a vector of vesicular stomatitis virus (VSV) has been examined in the laboratory using experimental procedures, such as immunohistochemical techniques, which show that VSV passes through the midgut barrier, and thus infected insects may be a competent biologic vector. VSV in the salivary glands further indicates that C. sonorensis is able to vector VSV during feeding. The presence of VSV in the eggs suggests that VSV may transfer vertically from females to their offspring. A protocol has been developed to isolate VSV RNA from paraffin embedded insects which can then be used for PCR analysis; this will enable confirmation of viral replication within insect tissues where virus is no longer viable. Nucleocapsid mRNA was successfully amplified from paraffin embedded Culicoides by RT-PCR. This confirmed VSV replication in the virus fed insects. An extensive time course in vivo analysis of VSV infection in the biting midge, Culicoides sonorensis showed that following ingestion, VSV replicated in salivary glands, ovarial tissues and was excreted. This evidence may suggest bite, vertical, and mechanical VSV transmission may occur in Culicoides sonorensis.

Recent ABADRL research identified a non-hematophagous insect (grasshopper) as a potential source of infection and maintenance reservoir of VSV. This study demonstrated that VSV replicates in grasshoppers and can spread between grasshoppers and cattle, which may lead to a better understanding of the epidemiology of sporadic outbreaks of VSV among western livestock. Analysis of the distribution of the sand fly, Lutzomyia apache, in the mid-Rio Grande River Valley, New Mexico, using geographic information system methods indicates a potential role for this sand fly in the epidemiology of VS viruses in the southwestern U.S.

The ABADRL insect vector genomics program has identified genes for which transcription increases during virus infection. In addition, midgut and salivary gland cDNA libraries were prepared and sequenced. This information has been released to international databases and will allow the development of new hypotheses of vector capacity as well as models to predict and understand the epidemiology of these diseases. Research that utilizes the genetic markers and cloned genes produced by the ABADRL will increase our understanding at the molecular level of the vector competence of C. sonorensis for bluetongue and epizootic hemorrhagic disease viruses.


6.What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end-user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products?
Information concerning the biological competence of Culicoides for VSV has been transferred to scientists in the fields of infectious disease research at the Colorado State University Infectious Diseases Colloquium as well as to virologists at the American Society for Virology and the Rocky Mountain Virology Club meeting. This information has also been transferred to stakeholders/members of the U.S. Animal Health Association.

Technology transfer may be expected of the VSV-specific IHC assay in the future. If a VSV outbreak occurs, the clinical similarity between VSV and foot and mouth disease will require rapid virus specific assays that can differentiate the two viruses. In some cases, the incriminating positive cell culture results will have already been fixed and stained, destroying the live sample. The IHC assay can confirm CPE as VSV-specific after live samples have been destroyed, and therefore will be valuable tools. The assay is for use SV infected cell cultures grown in 96, 48, 24, or 6-well plates. The use of synthetic pyrethroid insecticides as repellents for application to livestock has been transferred via verbal and written communication to horse owners, veterinarians and entomologists concerned about protecting animals from WNV. Control methods for larval stages of C. sonorensis have been transferred to white-tailed deer farmers who have used the recommendations to prevent annual deer die-offs from biting midge-transmitted viruses. The results of the multi-state Bluetongue Surveillance Pilot study have been reported to participating producer associations; this information will be useful in the formulation of regulations concerning export of U.S. cattle to BTV-free countries. Information concerning the presence and seasonal abundance of Culex tarsalis, the primary vector of WNV in the western U.S., has been transferred to state and county level personnel concerned with public health and mosquito control, as well as coal bed methane gas developers whose well drilling activities produce impoundments that support mosquito larval development.


7.List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below).
Presentations were made at the U.S. Animal Health Association Meeting, the National Cattlemen's Beef Association Meeting, American Society for Virology Meeting, Genetic Manipulation of Insects Keystone Symposium, Microbial Pathogenesis: Mechanisms of Infectious Disease, FASEB Summer Conference, Wyoming Stock Growers Association/Wyoming Woolgrowers Association Joint meeting, Colorado State University's Infectious Diseases Colloquium, and the Rocky Mountain Virology Club Meeting, Entomological Society of America Annual Meeting, Bureau of Land Management research progess meetings, Wyoming State Department of Health research review meetings, Cooperative Extension meetings. Information and technology also has been transferred to leaders of the U.S. Animal Health Association, the National Cattlemen's Beef Association, the Wyoming Stock Growers Association, the Wyoming Woolgrowers, APHIS - Veterinary Servieces, National Veterinary Services Laboratory, Ames, IA, and Centers for Animal Epidemiology and Health, Ft. Collins, CO.

"Making the Case Against the Biting Midge" by Rosalie M. Bliss. Agricultural Research, USDA, ARS, April 2005. This story about Drolet's work on the vector competence of the biting midge, Culicoides sonorensis was also picked up and published by the following popular press entities: Cattle Health Report, National Institute for Animal Agriculture; AnimalNet; BEEF; MyCattle.com; Animal Science Database; AgriSeek; SurfWax Anatomy News; USAG Magazine; Sciencedaily.com; Virtual Farm; CBS News Channel 5, Cheyenne; Department of Homeland Security IAIP Directorate, Daily Open Source Infrastructure Report. This story was also translated into Spanish and was published by ARS; La Opinion; and Engormix.com.

C.L. Campbell, K. Vandyke, B.S. Drolet, G.J. Letchworth, and W.C. Wilson. Culicoides gene discovery project reveals putative pharmacological factors in midge saliva. Entomological Society of America Annual Meeting, Salt Lake City, Utah. November 14-17, 2004.

C.L Campbell, K. Manninen, B.S. Drolet, and W.C. Wilson. Characterization of differentially expressed midge genes in susceptible and resistant Orbivirus vector populations. 24th Annual American Society for Virology Meeting, State College, PA. June 18-22, 2005. Paper No. 12-7. B.S. Drolet and M.A. Stuart. Vesicular stomatitis virus in the environment: Survivability in North Plains grassland species. Poster. 24th Annual American Society for Virology Meeting, State College, PA. June 18-22, 2005. Paper No. 42-1.

B.S. Drolet and M.A. Stuart. Vesicular stomatitis virus in the environment: Survivability in North Plains grassland species. Poster. 24th Annual American Society for Virology Meeting, State College, PA. June 18-22, 2005. Paper No. 42-1.

Yarnell, W. E., J. E. Lloyd, E. T. Schmidtmann, R. Kumar, D. Grubbs, and K. Wardlaw. Mosquitoes and West Nile virus in geographically contrasting areas of Wyoming. Poster presentation. Entomological Society of America national meeting, Salt Lake City, Utah. November 2004.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, and R. T. Mayer. Mosquitoes, coal bed methane energy development, and West Nile virus in Wyoming's Powder River basin. Poster presentation. Entomological Society of America national meeting, Salt Lake City, Utah. November, 2004.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, and R. T. Mayer. Coal bed methane, mosquitoes, and West Nile virus in the Powder River Basin, WY. Presentation. Bureau of Land Management sage grouse - coal bed methane development research review, Sheridan, WY. April, 2005.

Zou, L., and E. T. Schmidtmann. Satellite imagery and mosquito larval habitats in the Powder River Basin, WY. Presentation. Bureau of Land Management sage grouse - coal bed methane development research review, Sheridan, WY. April, 2005.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, and R. T. Mayer. Mosquito vectors of West Nile virus associated with coal bed methane impoundments in Wyoming's Powder River basin. Presentation. West Central Mosquito and Vector Control Association annual meeting. Cheyenne, WY. April 2005.

Yarnell, W. E., J. E. Lloyd, E. T. Schmidtmann, R. Kumar, D. Grubbs. Mosquito vector of West Nile virus in southeastern Wyoming. Presentation. West Central Mosquito and Vector Control Association annual meeting. Cheyenne, WY. April 2005.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, and R. T. Mayer. Mosquitoes, coal bed methane energy development, and West Nile virus in Wyoming's Powder River basin. Presentation. Wyoming State Health Department. Cheyenne, WY. May, 2005.

Yarnell, W. E., J. E. Lloyd, , E. T. Schmidtmann, R. Kumar, D. Grubbs, and K. Wardlaw. Mosquitoes and West Nile virus in geographically contrasting areas of Wyoming. Presentation. Wyoming State Health Department. Cheyenne, WY. May, 2005.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, and R. T. Mayer. Mosquitoes, coal bed methane energy development, and West Nile virus in Wyoming's Powder River basin. Presentation. Wyoming State Health Department. Gillette, WY. May, 2005.

Yarnell, W. E., J. E. Lloyd, E. T. Schmidtmann, R. Kumar, D. Grubbs, and K. Wardlaw. Mosquitoes and West Nile virus in geographically contrasting areas of Wyoming. Presentation. Wyoming State Health Department, Gillette, WY. May, 2005.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, and R. T. Mayer. Mosquitoes, coal bed methane energy development, and West Nile virus in Wyoming's Powder River basin. Presentation. Cooperative Extension Service, Torrington, WY. May, 2005.

Schmidtmann, E. T., G. D. Johnson, C. Y. Kato, B. L. Walker, D. E. Naugle, R. T. Mayer, and J. E. Lloyd. Coalbed methane impoundments, mosquitoes, and West Nile virus: an emerging problem? Wyoming Geological Society Bulletin, Public Information Circular 43, p 87- 89.


Review Publications
Drolet, B.S., Campbell, C.L., Stuart, M.A., Wilson, W.C. 2005. Vector competence of culicoides sonorensis (diptera: ceratopogonidae) for vesicular stomatitis virus. Journal of Medical Entomology. 42(3): 409-418 (2005)

Schmidtmann, E.T. 2005. Using synthetic pyrethroids to protect livestock from insect blood-feeding and transmission of viral pathogens. 49th Livestock Insect Work Conference. Bozeman, MT.

Campbell, C.L., Vandyke, K., Letchworth III, G.J., Drolet, B.S., Hanekamp, T., Wilson, W.C. 2005. Midgut and salivary gland transcriptomes of the arbovirus vector culicoides sonorensis (diptera: ceratopogonidae). Insect Molecular Biology. 14(2):121-136.

Herrero, M.V., Yarnell, W.E., Schmidtmann, E.T. 2004. Landscape associations of the sand fly, Lutzomyia (Heleocyrtomyia) apache (Diptera: Psychodidae), in the southwestern United States: a geographic information system analysis. Journal of Vector Ecology. 29: 205-211.

Green, A.L., Dargatz, D.A., Schmidtmann, E.T., Herrero, M.V., Seitzinger, A.H., Ostlund, E.N., Wagner, B.A., Moser, K.M., Wineland, N.E., Walton, T.E. 2005. Risk factors associated with herd-level bluetongue virus exposure of cattle in Nebraska, North Dakota, and South Dakota. American Journal of Veterinary Research. 66: 853-860.

Last Modified: 10/20/2014
Footer Content Back to Top of Page