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Donahue W.A.,Sierra Research Laboratories | Showler A.T.,U.S. Department of Agriculture | Donahue M.W.,Sierra Research Laboratories | Vinson B.E.,Sierra Research Laboratories | And 2 more authors.
Biopesticides International | Year: 2015

The common bed bug, Cimex lectularius (L.) (Hemiptera: Cimicidae) is undergoing a rapid resurgence in the United States during the last decade which has created a notable pest management challenge largely because the pest has developed resistance against DDT, organophosphates, carbamates, and pyrethroids, the latter class of insecticide being most commonly used today. Eight nonconventional insecticides Orange Guard (a.i., d-limonene), Natria Home Pest Control (a.i., soy bean oil and eugenol), RestAsure (a.i., sodium laurel sulfate, sodium chloride, and potassium sorbate), CedarCide (a.i. cedar oil), Essentria Broadcast Insecticide (a.i., 2-phenethyl propionate, rosemary oil, and peppermint oil), EcoSmart Organic Home Pest Control (a.i., 2-phenethyl propionate, clove oil, rosemary oil, peppermint oil, and thyme oil), Cirkil (a.i.,neem oil) and CimeXa (a.i., silica gel) were compared with two pyrethorids Bonide Bedbug Killer (a.i.,permethrin) and D-Force (a.i.,deltamethrin) as positive controls, and water for direct contact spray knockdown and lethal effects in the laboratory over 4 days. Orange Guard, CedarCide, Essentria, EcoSmart, and Cirkil provided extensive knockdown within 15 min (recovery was, at most, negligible), and caused 80 to 100% mortality within a day making them as effective as the two pyrethroids. CimeXa did not cause appreciable knockdown, but nearly complete mortality was achieved within a day. Product effects in terms of active ingredients and factors that might increase and decrease product effectiveness, such as cimicid aggregation behavior and residual effects, are discussed. Source

Fedorova N.,University of California at Berkeley | Kleinjan J.E.,Alameda County Vector Control Services District | James D.,Alameda County Vector Control Services District | Hui L.T.,Alameda County Vector Control Services District | Lane R.S.,University of California at Berkeley
Ticks and Tick-borne Diseases | Year: 2014

The diversity of Lyme disease (LD) and relapsing fever (RF)-group spirochetes in the metropolitan San Francisco Bay area in northern California is poorly understood. We tested Ixodes pacificus, I. spinipalpis, and small mammals for presence of borreliae in Alameda County in the eastern portion of San Francisco Bay between 2009 and 2012. Analyses of 218 Borrelia burgdorferi sensu lato (Bb sl) culture or DNA isolates recovered from host-seeking I. pacificus ticks revealed that the human pathogen Bb sensu stricto (hereinafter, B. burgdorferi) had the broadest habitat distribution followed by B. bissettii. Three other North American Bb sl spirochetes, B. americana, B. californiensis and B. genomospecies 2, also were detected at lower prevalence. OspC genotyping of the resultant 167 B. burgdorferi isolates revealed six ospC alleles (A, D, E3, F, H and K) in I. pacificus. A novel spirochete belonging to the Eurasian Bb sl complex, designated CA690, was found in a questing I. spinipalpis nymph. Borrelia miyamotoi, a relapsing-fever (RF) group spirochete recently implicated as a human pathogen, was detected in 24 I. pacificus. Three rodent species were infected with Bb sl: the fox squirrel (. Sciurus niger) with B. burgdorferi, and the dusky-footed wood rat (. Neotoma fuscipes) and roof rat (. Rattus rattus) with B. bissettii. Another spirochete that clustered phylogenetically with the Spanish R57 Borrelia sp. in a clade distinct from both the LD and RF groups infected some of the roof rats. Together, eight borrelial genospecies were detected in ticks or small mammals from a single Californian county, two of which were related phylogenetically to European spirochetes. © 2014 Elsevier GmbH. Source

Conroy C.J.,University of California at Berkeley | Rowe K.C.,University of California at Berkeley | Rowe K.M.C.,University of California at Berkeley | Kamath P.L.,University of California at Berkeley | And 6 more authors.
Biological Invasions | Year: 2013

Invasive species can have complex invasion histories, harbor cryptic levels of diversity, and pose taxonomic problems for pest management authorities. Roof rats, Rattus rattus sensu lato, are common invasive pests of the San Francisco Bay Area in California, USA. They are a significant health risk and pest management efforts impose a large financial investment from public institutions and private individuals. Recent molecular genetic and taxonomic studies of black rats in their native range in Asia have shown that the species is a complex of two karyotypic forms and four mitochondrial genetic lineages that may represent four distinct species. We used mtDNA sequences and nuclear microsatellite variation to identify which mitochondrial lineages of the R. rattus group are present in the San Francisco Bay Area and to test for gene flow among them. We recovered specimens with mtDNA sequences representing two of the major mtDNA lineages of the R. rattus group. Microsatellite variation, however, was not structured in concordance with mtDNA lineages, suggesting a more complex history involving hybridization and introgression between these lineages. Although Aplin et al. (2011) and Lack et al. (2012) reported R. rattus Lineage II in North America, this is the first detailed examination of possible gene flow amongst lineages in this region. © 2012 Springer Science+Business Media B.V. Source

Brant S.V.,University of New Mexico | Cohen A.N.,Center for Research on Aquatic Bioinvasions | James D.,Alameda County Vector Control Services District | Hui L.,Alameda County Vector Control Services District | And 2 more authors.
Emerging Infectious Diseases | Year: 2010

Cercarial dermatitis (swimmer's itch) is caused by the penetration of human skin by cercariae of schistosome parasites that develop in and are released from snail hosts. Cercarial dermatitis is frequently acquired in freshwater habitats, and less commonly in marine or estuarine waters. To investigate reports of a dermatitis outbreak in San Francisco Bay, California, we surveyed local snails for schistosome infections during 2005-2008. We found schistosomes only in Haminoea japonica, an Asian snail first reported in San Francisco Bay in 1999. Genetic markers place this schistosome within a large clade of avian schistosomes but do not match any species for which there are genetic data. It is the second known schistosome species to cause dermatitis in western North American coastal waters; these species are transmitted by exotic snails. Introduction of exotic hosts can support unexpected emergence of an unknown parasite with serious medical or veterinary implications. Source

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