Diversity and Prevalence of Ectoparasites on Backyard Chicken Flocks in California
Peridomestic ("backyard") chicken flocks are gaining popularity in the developed world (e.g., North America or Europe), yet little is known regarding prevalence or severity of their ectoparasites. Therefore, five birds on each of 20 properties throughout southern California were surveyed in summer for on-host (permanent) and off-host dwelling (temporary) ectoparasites. Only four premises (20%) were entirely free of ectoparasites. In declining order of prevalence (% of premises), permanent ectoparasites included six chicken louse species: Menacanthus stramineus (Nitzsch) (50%), Goniocotes gallinae (De Geer) (35%), Lipeurus ...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Murillo, A. C., Mullens, B. A. Tags: Short Communication Source Type: research
Estimating Field Densities of Haematobia irritans (Diptera: Muscidae) Using Direct Visual Field Counts Versus Photographic Assessments
Horn flies, Haematobia irritans (L.), were photographed on cattle and then immediately estimated visually in the field on pastured beef cattle in southern California. Horn flies were counted in the pictures later on a computer screen. For 479 counts on individual cattle, the concordance correlation coefficient between the visual and photo-based assessments was 0.790, but was better for the higher half of the counts (0.732) than for the lower half of the counts (0.217). Major axis regression indicated that visual estimates were consistently higher than the number of flies counted in the pictures across the entire density ra...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Mullens, B. A., Soto, D., Gerry, A. C. Tags: Short Communication Source Type: research
Determination of Insecticidal Effect (LC50 and LC90) of Organic Fatty Acids Mixture (C8910+Silicone) Against Aedes aegypti and Aedes albopictus (Diptera: Culicidae)
Emerging and re-emerging vector-borne diseases such as chikungunya and dengue and associated Aedes vectors are expanding their historical ranges; thus, there is a need for the development of novel insecticides for use in vector control programs. The mosquito toxicity of a novel insecticide and repellent consisting of medium-chain carbon fatty acids (C8910) was examined. Determination of LC50 and LC90 was made against colony-reared Aedes aegypti (L.) and Aedes albopictus (Skuse) using probit analysis on mortality data generated by Centers for Disease Control and Prevention bottle bioassays. Six different concentrations of C...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Dunford, J. C., Falconer, A., Leite, L. N., Wirtz, R. A., Brogdon, W. G. Tags: Short Communication Source Type: research
Panola Mountain Ehrlichia in Amblyomma maculatum From the United States and Amblyomma variegatum (Acari: Ixodidae) From the Caribbean and Africa
Panola Mountain Ehrlichia (PME) has been suggested as an emerging pathogen of humans and dogs. Domestic goats and white-tailed deer (Odocoileus virginianus) are also susceptible and likely serve as reservoirs. Experimentally, both the lone star tick (Amblyomma americanum (L.)) and the Gulf Coast tick (Amblyomma maculatum Koch) can transmit PME among deer and goats. In the current study, we detected PME in adult wild-caught A. maculatum from the United States and Amblyomma variegatum (F.) from the Caribbean and Africa. This significantly expands the range, potential tick vectors, and risk for exposure to PME. (Source: Journ...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Loftis, A. D., Kelly, P. J., Paddock, C. D., Blount, K., Johnson, J. W., Gleim, E. R., Yabsley, M. J., Levin, M. L., Beati, L. Tags: Short Communication Source Type: research
Mild-Vectolysis: A Nondestructive DNA Extraction Method for Vouchering Sand Flies and Mosquitoes
This study presents Mild-Vectolysis, the first nondestructive DNA extraction methodology for vouchering taxa of mosquitoes and sand flies, which provided sufficient amounts of DNA, tested in a verified barcode (cytochrome oxidase I gene), while preserving their morphological integrity. Application of the method to sand flies allowed successful insect identification post DNA extraction, as all basic taxonomical structures necessary for identification (pharynx, cybarium, and genitalia) remained intact. The development of the methodology was more challenging in mosquitoes, due to the fragility of key morphological characters ...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Giantsis, I. A., Chaskopoulou, A., Bon, M. C. Tags: Short Communication Source Type: research
Dengue Virus-1 Infection Did Not Alter the Behavioral Response of Aedes aegypti (Diptera: Culicidae) to DEET
No licensed vaccine or antiviral drug against dengue virus (DENV) is available; therefore, most of the effort to prevent this disease is focused on reducing vector–host interactions. One of the most widely accepted methods of blocking vector–human contact is to use insect repellents to interfere with mosquito host-seeking behavior. Some arboviruses can replicate in the nervous system of the vector, raising the concern that arboviral infection may alter the insect behavioral response toward chemical stimuli. Three different Aedes aegypti (L.) mosquito cohorts: DENV-1-injected, diluent-injected, and uninjected we...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Sugiharto, V. A., Murphy, J. R., Turell, M. J., Olsen, C. H., Stewart, V. A., Colacicco-Mayhugh, M. G., Grieco, J. P., Achee, N. L. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
The Impact of Cycling Temperature on the Transmission of West Nile Virus
West Nile virus (WNV) is an important cause of disease in humans and animals. Risk of WNV infection varies seasonally, with the greatest risk during the warmest parts of the year due in part to the accelerated extrinsic incubation rate of the virus in mosquitoes. Rates of extrinsic incubation have been shown in constant-temperature studies to increase as an approximately linear function of temperature, but for other vector-borne pathogens, such as malaria or dengue virus, nonlinear relationships have been demonstrated under cycling temperatures near the thermal limits of pathogen replication. Using typical daily air temper...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Danforth, M. E., Reisen, W. K., Barker, C. M. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
Infection Prevalence, Bacterial Loads, and Transmission Efficiency in Oropsylla montana (Siphonaptera: Ceratophyllidae) One Day After Exposure to Varying Concentrations of Yersinia pestis in Blood
Unblocked fleas can transmit Yersinia pestis, the bacterium that causes plague, shortly (≤4 d) after taking an infectious bloodmeal. Investigators have measured so-called early-phase transmission (EPT) efficiency in various fleas following infection with highly bacteremic blood (≥108 cfu/ml). To date, no one has determined the lower limit of bacteremia required for fleas to acquire and transmit infection by EPT, though knowing this threshold is central to determining the length of time a host may be infectious to feeding fleas. Here, we evaluate the ability of Oropsylla montana (Baker) to acquire and transmit Y. pest...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Boegler, K. A., Graham, C. B., Johnson, T. L., Montenieri, J. A., Eisen, R. J. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
Host-Feeding Sources and Infection With Trypanosoma cruzi of Triatoma infestans and Triatoma eratyrusiformis (Hemiptera: Reduviidae) From the Calchaqui Valleys in Northwestern Argentina
We assessed the prevalence of infection with Trypanosoma cruzi, parasite genotypes (discrete typing units, DTUs), and the host-feeding sources of domestic and peridomestic Triatoma infestans Klug and Triatoma eratyrusiformis Del Ponte in eight rural communities of the subandean Calchaqui valleys in northwestern Argentina. We sought to analyze their epidemiological role in the context of routine vector surveillance and control actions. Infection with T. cruzi was determined by optic microscopy or polymerase chain reaction (PCR) amplification of the hypervariable region of kinetoplast DNA minicircles. Parasite genotypes were...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Cecere, M. C., Leporace, M., Fernandez, M. P., Zarate, J. E., Moreno, C., Gürtler, R. E., Cardinal, M. V. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
Dynamics of Exposure to Rickettsia parkeri in Cattle in the Parana River Delta, Argentina
Several cases of human rickettsiosis caused by Rickettsia parkeri were recently documented in the Paraná River delta of Argentina, where the tick vector is Amblyomma triste Koch. As cattle suffer recurrent A. triste infestations, they are at risk of becoming infected with R. parkeri. Herein we investigated the dynamics of R. parkeri and its A. triste vector in a herd of beef cattle. Cattle were followed for 18 mo and samples were analyzed for the presence of antibodies against four Rickettsia species (R. parkeri, Rickettsia bellii, Rickettsia amblyommii, and Rickettsia felis) and also for the presence of rickettsial...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Monje, L. D., Costa, F. B., Colombo, V. C., Labruna, M. B., Antoniazzi, L. R., Gamietea, I., Nava, S., Beldomenico, P. M. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
Expansion of the Knockdown Resistance Frequency Map for Human Head Lice (Phthiraptera: Pediculidae) in the United States Using Quantitative Sequencing
Pediculosis is a prevalent parasitic infestation of humans, which is increasing due, in part, to the selection of lice resistant to either the pyrethrins or pyrethroid insecticides by the knockdown resistance (kdr) mechanism. To determine the extent and magnitude of the kdr-type mutations responsible for this resistance, lice were collected from 138 collection sites in 48 U.S. states from 22 July 2013 to 11 May 2015 and analyzed by quantitative sequencing. Previously published data were used for comparisons of the changes in the frequency of the kdr-type mutations over time. Mean percent resistance allele frequency (mean %...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Gellatly, K. J., Krim, S., Palenchar, D. J., Shepherd, K., Yoon, K. S., Rhodes, C. J., Lee, S. H., Marshall Clark, J. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
Biological and Chemical Characterization of a New Larvicide Ovitrap Made of Plastic With Pyriproxyfen Incorporated for Aedes aegypti (Diptera: Culicidae) Control
In this study, we performed a biological and chemical characterization of a new ovitrap prototype manufactured by injection molding of low-density polyethylene (LDPE) with the larvicide pyriproxyfen. Our research shows that pyriproxyfen was immediately released from the LDPE into the water of the ovitrap and led to an emergence inhibition of 100% for over 30 weeks. In addition, ovitraps continued to show a high larvicidal activity after over 20 washes. Pyriproxyfen was detectable in the water after 20 s and reached a peak after 24 h. Our results show that this ovitrap can be an effective, inexpensive, and low-maintenance t...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Harburguer, L., Licastro, S., Masuh, H., Zerba, E. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
Bed Bugs: Prevalence in Low-Income Communities, Residents Reactions, and Implementation of a Low-Cost Inspection Protocol
We examined bed bug prevalence in 2,372 low-income apartments within 43 buildings in four New Jersey cities using a combination of resident interviews, brief visual inspections, and monitoring with Climbup Insect Interceptors. Infestation rates ranged from 3.8 to 29.5% among the buildings, with an overall infestation rate of 12.3%. Within each apartment, the bed area trapped significantly more bed bugs per trap than the sofa (or upholstered chair) area. African American residents had a proportionally higher number of bed bug infestations than white residents. Women were more likely to report bed bug bite symptoms than men....
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Wang, C., Singh, N., Zha, C., Cooper, R. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
An Evaluation of Light-Emitting Diode (LED) Traps at Capturing Phlebotomine Sand Flies (Diptera: Psychodidae) in a Livestock Area in Brazil
A study to evaluate the use of light-emitting diodes (LEDs) as an attractant for phlebotomine sand flies at two animal pens in a livestock area in Brazil was performed. Light-suction traps were operated overnight with the following light sources: green, blue, and incandescent (control) lights. In total, 22 individual collections were made at each site and 44 with each trap type. In total, 2,542 specimens belonging to 14 phlebotomine species were collected. The most abundant species in the light traps were Nyssomyia whitmani, Evandromyia evandroi, Micropygomyia goiana, Lutzomyia longipalpis, and Bichromomyia flaviscutellata...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Silva, F. S., da Silva, A. A., Rebelo, J. M. M. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
Synergism of the IGRs Methoprene and Pyriproxyfen Against Larval Cat Fleas (Siphonaptera: Pulicidae)
Insect growth regulators (IGRs) methoprene and pyriproxyfen are widely used as topical treatments to pets or applied to the indoor environment to control cat fleas, Ctenocephalides felis (Bouché). The toxicity of methoprene, pyriproxyfen, and combinations of both IGRs to cat flea larvae was determined. The LC50 of methoprene and pyriproxyfen applied to larval rearing medium was 0.39 and 0.19 ppm, respectively. Combinations of methoprene:pyriproxyfen in ratios of 1:1, 5:1, 10:1, and 20:1 produced LC50s of 0.06, 0.09, 0.19, and 0.13 ppm, respectively. The pyriproxyfen synergized the activity of methoprene as indicated...
Source: Journal of Medical Entomology - May 19, 2016 Category: Biology Authors: Rust, M. K., Lance, W., Hemsarth, H. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
