Publications by authors named "Elizabeth Dykstra"

In response to notable increases in tick-associated illnesses in the United States, recent public health policies encouraged multi-sector collaborative approaches to preventing vector-borne diseases. Primary prevention strategies focus on educating the public about risks for tick-borne diseases and encouraging adoption of personal protection strategies. Accurate descriptions of when and where people are at risk for tick-borne diseases aid in the optimization of prevention messaging.

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Lyme disease is the most common vector-borne disease in the United States and Canada. The primary vector for the causative agent of Lyme disease, Borrelia burgdorferi, in the Pacific Northwest is the western blacklegged tick, Ixodes pacificus. Using active tick surveillance data from British Columbia, Canada, and Washington State, USA, habitat suitability models using MaxEnt (maximum entropy) were developed for to predict its current and mid-century geographic distributions.

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The Pacific Coast tick (Dermacentor occidentalis Marx, 1892) is a frequently encountered and commonly reported human-biting tick species that has been recorded from most of California and parts of southwestern Oregon, southcentral Washington, and northwestern Mexico. Although previous investigators have surveyed populations of D. occidentalis for the presence of Rickettsia species across several regions of California, populations of this tick have not been surveyed heretofore for rickettsiae from Baja California, Oregon, or Washington.

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Dermacentor andersoni, the Rocky Mountain wood tick, occurs predominantly in the northwestern United States and southwestern Canada. There are relatively few contemporary data to evaluate the occurrence of Rickettsia and Anaplasma species in D. andersoni in western North America, and even less information about these associations in the state of Washington, where this tick species is widely distributed and often bites humans.

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Tickborne diseases are rare in Washington, USA, and the ecology of these pathogens is poorly understood. We integrated surveillance data from humans and ticks to better describe their epidemiology and ecology. During 2011-2016, a total of 202 tickborne disease cases were reported in Washington residents.

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, a common human-biting tick found throughout the eastern half and along the west coast of the United States, is a vector of multiple bacterial pathogens. Historically, has been considered a primary vector of , the causative agent of Rocky Mountain spotted fever. A total of 883 adult , collected between 2012 and 2017 from various locations in 12 states across the United States, were screened for rickettsial DNA.

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From July 2006 through August 2017, a passive surveillance study of Ixodes ticks submitted from California, Oregon, and Washington was conducted by the TickReport program at the University of Massachusetts, Amherst. In total, 549 human-biting Ixodes ticks were submitted comprising both endemic and nonendemic species. We found that 430 endemic ticks were from 3 Ixodes species: Ixodes pacificus, Ixodes spinipalpis, and Ixodes angustus, whereas Ixodes scapularis (n = 111) was the most common species among the 119 nonendemic ticks.

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Wohlfahrtiimonas species bacteria were isolated from the bloodstream of a patient with septicemia and wound myiasis. Environmental investigations identified a Wohlfahrtiimonas sp. among insects in the Americas and in a previously undescribed vector, the green bottle fly (Lucilia sericata).

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Routine West Nile virus (WNV) surveillance in 2016 by the Washington State Department of Health resulted in 1 new state distribution record for Aedes hendersoni, bringing the total number of mosquito species reported from Washington to 52. We also report new county records for Aedes japonicus japonicus, Aedes togoi, and Culex salinarius .

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Arthropod-borne viruses (arboviruses) threaten the health of humans, livestock, and wildlife. West Nile virus (WNV), the world's most widespread arbovirus, invaded the United States in 1999 and rapidly spread across the county. Although the ecology of vectors and hosts are key determinants of WNV prevalence across landscapes, the factors shaping local vector and host populations remain unclear.

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The records of mosquito species in eastern Washington State are sparse, relative to other areas of the state. To improve the knowledge of mosquito diversity and activity in eastern Washington, mosquito surveillance activities were conducted during the summers of 2007 and 2008, which resulted in the collection of 8 species of mosquitoes from 4 counties where they had not been previously recorded.

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Insecticide use continues to be the primary control strategy to reduce insect vector populations. Concerns about insecticide resistance in target organisms, environmental degradation, and possible deleterious impact on human health have led researchers to seek a variety of alternative control strategies. We tested a relatively new method for controlling mosquitoes using host immune response.

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The previous phase of the present study revealed that when crude extracts of Culex pipiens midgut, ovaries, and salivary glands are injected into New Zealand White (NZW) rabbits (Oryctolagus cuniculus), rabbits immunized with midgut extract exert the greatest negative impact on adult Cx. pipiens survival and fecundity. This study was conducted to further our understanding of the immunogenic nature of the aforementioned antigenic preparations, thus providing data for the ultimate goal of developing a vaccine against the numerous Cx.

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Phlebotumus kazeruni, a blood-feeding, xerophilic sand fly species found broadly throughout North Africa and Western Asia, is a suspected vector of cutaneous leishmaniasis (CL). Following successful laboratory colonization of this species, we employed the murine (BALB/c) infection model to determine whether our Sinai strain of P. kazeruni was able to successfully acquire, develop, and transmit a Sinai strain of Leishmania major.

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The effectiveness of 1-octen-3-ol (octenol) as an attractant for collecting medically important psychodids has never been reported. This study evaluated the effects of carbon dioxide (CO2) and octenol released at 2 rates, individually and in combination, as attractants for adult sand flies in a small village in southern Egypt. Four sand fly species were collected: Phlebotomus papatasi, P.

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We compared the VecTestTM dipstick assay for detection of Plasmodium sporozoites in Anopheles vectors of malaria with standard circumsporozoite (CS) microplate ELISA for detection of Plasmodium falciparum circumsporozoite protein (PfCSP) in Anopheles mosquitoes. Mosquitoes were collected from a malaria endemic site (Kassena Nankana district) in northern Ghana. Of 2620 randomly sampled mosquitoes tested, the standard CS-ELISA gave a sporozoite rate of 10.

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