Synanthropic Cockroaches (Blattidae: Periplaneta spp.) Harbor Pathogenic Leptospira in Colombia
Leptospirosis cases in Colombia are typically linked to peridomestic rodents; however, empirical data suggest that Leptospira-infected patients with no apparent exposure to these reservoirs are common. Cockroaches (Periplaneta spp.) have equal or greater interaction with humans than rodents, yet their potential role as carriers of Leptospira has not been assessed. We determined if pathogenic Leptospira is harbored by Periplaneta spp. in Cali (Colombia) and the variables influencing this relationship. Fifty-nine cockroaches were captured from seven sites and DNA was extracted from the body surface and digestive tract for a ...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Gonzalez-Astudillo, V., Bustamante-Rengifo, J. A., Bonilla, A., Lehmicke, A. J. J., Castillo, A., Astudillo-Hernandez, M. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
Effect of Rickettsia rickettsii (Rickettsiales: Rickettsiaceae) Infection on the Biological Parameters and Survival of Its Tick Vector--Dermacentor variabilis (Acari: Ixodidae)
Rocky Mountain spotted fever, caused by Rickettsia rickettsii, is a potentially fatal tick-borne disease spread from North America to Argentina. The major vectors of R. rickettsii in the United States are Dermacentor andersoni Stiles and Dermacentor variabilis (Say). It is generally believed that vector ticks serve as major reservoirs of R. rickettsii in nature; however, the ability of ticks to support the indefinite perpetuation of R. rickettsii has been challenged by reports of deleterious effects of rickettsial infection on D. andersoni. To better elucidate the relationship of the pathogen with D. variabilis, we assesse...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Schumacher, L., Snellgrove, A., Levin, M. L. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
How do Nutritional Stress and La Crosse Virus Infection Interact? Tests for Effects on Willingness to Blood Feed and Fecundity in Aedes albopictus (Diptera: Culicidae)
Evolutionary theory predicts that vector-borne pathogens should have low virulence for their vector because of selection against pathogens that harm the vector sufficiently to reduce transmission. Environmental factors such as nutritional stress can alter vector–pathogen associations by making the vectors more susceptible to pathogens (condition-dependent competence) and vulnerable to the harm caused by pathogen replication (condition-dependent virulence). We tested the hypotheses of condition-dependent competence and condition-dependent virulence by examining the interactive effects of short-term sugar deprivation a...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Westby, K. M., Muturi, E. J., Juliano, S. A. Tags: Vector/Pathogen/Host Interaction, Transmission Source Type: research
A Novel in vitro Bioassay to Explore the Repellent Effects of Compounds Against Mosquito Aedes aegypti (Diptera: Culicidae)
Mosquitoes are vectors for many pathogens resulting in many deaths of humans. Repellents play an important role in reducing mosquito bites and the spread of mosquito-borne diseases. Currently, Klun & Debboun (K & D) and human-arm-based bioassay systems are used to identify repellent properties of compounds, extracts, and essential oils. Risks involved with human-arm-based systems are allergic reactions and limited replicates. We are reporting an in vitro bioassay method "NCNPR repellent bioassay (NCNPR-RB)" that can closely simulate the results of the cloth patch bioassay system used to determine repellency ag...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Rehman, J. U., Tabanca, N., Khan, I. A. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
A Novel Nit Comb Concept Using Ultrasound Actuation: Preclinical Evaluation
Nit combing and removal of head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), eggs is a task made more difficult because "nit combs" vary in efficiency. There is currently no evidence that the binding of the eggshell to the hair can be loosened chemically and few hair treatments improve the slip of the louse eggs along the hair. Ultrasound, applied through the teeth of a nit comb, may facilitate the flow of fluids into the gap between the hair shaft and the tube of fixative holding louse eggs in place to improve lubrication. Ultrasound alone had little effect to initiate sliding, requiring a force of 12...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Burgess, M. N., Brunton, E. R., Burgess, I. F. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
Selective Insecticide Applications Directed Against Triatoma infestans (Hemiptera: Reduviidae) Affected a Nontarget Secondary Vector of Chagas Disease, Triatoma garciabesi
The control of nondomiciliated triatomine species adapted to peridomestic habitats represents a challenge because they are connected to sylvatic colonies, and pyrethroid insecticides have limited effects outdoors. The effects of residual insecticide spraying have rarely been assessed on secondary triatomines. Triatoma garciabesi (Carcavallo, Martinez, Cichero, Prosen & Ronderos, 1967) is a nontarget vector that inhabits the dry western Chaco region, and a member of the Triatoma sordida Stål 1859 complex. Little is known on the capacity of T. garciabesi to invade and establish viable domestic or peridomestic colon...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Rodriguez-Planes, L. I., Vazquez-Prokopec, G. M., Cecere, M. C., Canale, D. M., Gürtler, R. E. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
The Influence of Ambient Temperature on the Susceptibility of Aedes aegypti (Diptera: Culicidae) to the Pyrethroid Insecticide Permethrin
Insecticides are the most common strategy used for the management of mosquitoes. Changes in ambient temperature can alter the toxicity of insecticides to ectothermic organisms. Studies show organophosphate insecticides exhibit a positive correlation between ambient temperature and mortality for many insect species, and carbamate insecticides exhibit a slightly negative correlation between ambient temperature and mortality. Pyrethroid insecticides exhibit a distinctly negative correlation between increasing ambient temperature and mortality for insects. However, this relationship has not been systematically studied for adul...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Whiten, S. R., Peterson, R. K. D. Tags: Vector Control, Pest Management, Resistance, Repellents Source Type: research
Monitoring Dry Season Persistence of Anopheles gambiae s.l. Populations in a Contained Semi-Field System in Southwestern Burkina Faso, West Africa
To gain insight into the dry season survival strategies of Anopheles gambiae s.l., a new contained semi-field system was developed and used for the first time in Burkina Faso, West Africa. The system consisted of a screened greenhouse within which the local environment was reproduced, including all ecological requirements for mosquito development cycle completion. The system was seeded with the progenies of female Anopheles gambiae, Anopheles coluzzii, and Anopheles arabiensis collected in the vicinity of the greenhouse during the rainy season. After successful establishment in the semi-field system, mosquito populations w...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Mamai, W., Simard, F., Couret, D., Ouedraogo, G. A., Renault, D., Dabire, K. R., Mouline, K. Tags: Sampling, Distribution, Dispersal Source Type: research
Geographic Distribution and Ecology of Triatoma dimidiata (Hemiptera: Reduviidae) in Colombia
Triatoma dimidiata Latreille is the second most important vector of Chagas’ disease in Colombia and is found in urban and periurban areas. From January 2007 to June 2008, we performed field work in 8 departments, 18 municipalities, and 44 rural villages, covering most of its known distribution and all of its ecological zones in the country. The goal was to determine the geographical distribution, the ecology, and house infestation indices of T. dimidiata over its range and hence the Chagas’ disease transmission risk. In Colombia, T. dimidiata occupies a wide variety of ecosystems, from transformed ecosystems in...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Parra-Henao, G., Angulo, V. M., Osorio, L., Jaramillo-O, N. Tags: Sampling, Distribution, Dispersal Source Type: research
Seasons, Searches, and Intentions: What The Internet Can Tell Us About The Bed Bug (Hemiptera: Cimicidae) Epidemic
The common bed bug (Cimex lectularius L.) is once again prevalent in the United States. We investigated temporal patterns in Google search queries for bed bugs and co-occurring terms, and conducted in-person surveys to explore the intentions behind searches that included those terms. Searches for "bed bugs" rose steadily through 2011 and then plateaued, suggesting that the epidemic has reached an equilibrium in the United States. However, queries including terms that survey respondents associated strongly with having bed bugs (e.g., "exterminator," "remedies") continued to climb, while terms more closely associated with in...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Sentana-Lledo, D., Barbu, C. M., Ngo, M. N., Wu, Y., Sethuraman, K., Levy, M. Z. Tags: Population and Community Ecology Source Type: research
A Dynamic Population Model to Investigate Effects of Climate and Climate-Independent Factors on the Lifecycle of Amblyomma americanum (Acari: Ixodidae)
In this study, we explored the roles of these processes by simulating seasonal activity patterns using models with site-specific temperature and day-length-dependent processes. We first modeled the transitions from engorged larvae to feeding nymphs, engorged nymphs to feeding adults, and engorged adult females to feeding larvae. The simulated seasonal patterns were compared against field observations at three locations in United States. Simulations suggested that 1) during the larva-to-nymph transition, some larvae undergo no diapause while others undergo morphogenetic diapause of engorged larvae; 2) molted adults undergo ...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Ludwig, A., Ginsberg, H. S., Hickling, G. J., Ogden, N. H. Tags: Population and Community Ecology Source Type: research
Larval Temperature-Food Effects on Adult Mosquito Infection and Vertical Transmission of Dengue-1 Virus
Temperature–food interactions in the larval environment can affect life history and population growth of container mosquitoes Aedes aegypti (L.) and Aedes albopictus Skuse, the primary vectors of chikungunya and dengue viruses. We used Ae. aegypti, Ae. albopictus, and dengue-1 virus (DENV-1) from Florida to investigate whether larval rearing temperature can alter the effects of larval food levels on Ae. aegypti and Ae. albopictus life history and DENV-1 infection and vertical transmission. Although we found no effect of larval treatments on survivorship to adulthood, DENV-1 titer, or DENV-1 vertical transmission, rat...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Buckner, E. A., Alto, B. W., Lounibos, L. P. Tags: Population and Community Ecology Source Type: research
Description of Psathyromyia (Psathyromyia) baratai sp. n. (Diptera: Psychodidae: Phlebotominae) From Cantareira State Park, Sao Paulo, Brazil
We describe a new species in the Shannoni complex, Psathyromyia baratai sp. n., on the basis of morphological and morphometric characters, a species which due to its great morphological similarity with Psathyromyia abonnenci, Psathyromyia limai, and Psathyromyia shannoni has been erroneously identified with one or other of them for >60 yr. (Source: Journal of Medical Entomology)
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Sabio, P. B., Andrade, A. J., Galati, E. A. B. Tags: Morphology, Systematics, Evolution Source Type: research
Simulium (Gomphostilbia) merapiense sp. nov. (Diptera: Simuliidae) from Java, Indonesia
Simulium (Gomphostilbia) merapiense sp. nov. is described based on females, males, pupae, and mature larvae from Yagyakarta, Java, Indonesia. This new species is placed in the Simulium epistum species-group, and is characterized by the pupal gill with eight short filaments all arising at the same level from a short stalk, somewhat enlarged basal fenestra, entirely bare pupal head and thoracic integument, and small and short larval postgenal cleft. These characters rarely are found in the subgenus. Taxonomic notes are given to separate this new species from related species of the S. epistum species-group. (Source: Journal o...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Takaoka, H., Sofian-Azirun, M., Yacob, Z., Chen, C. D., Low, V. L., Zaid, A. Tags: Morphology, Systematics, Evolution Source Type: research
Decomposition of Concealed and Exposed Porcine Remains in the North Carolina Piedmont
We examined the decomposition and subsequent insect colonization of small pig carrion (Sus scrofa (L.)) placed in concealed and open environments during spring, summer, and fall in Raleigh, North Carolina, as a model for juvenile human remains. Remains were concealed in simulated attics in three manners, ranging from minimal to well-concealed. Concealment had a significant effect on the insect community colonizing the remains across all three seasons; the beetles Necrobia rufipes (DeGeer) (Cleridae) and Dermestes maculatus (DeGeer) (Coleoptera: Dermestidae) were the only species indicative of remains located indoors, where...
Source: Journal of Medical Entomology - January 12, 2016 Category: Biology Authors: Cammack, J. A., Cohen, A. C., Kreitlow, K. L., Roe, R. M., Watson, D. W. Tags: Direct Injury, Myiasis, Forensics Source Type: research
