Infection with Borrelia miyamotoi in California, USA, has been suggested by serologic studies. We diagnosed B. miyamotoi infection in an immunocompromised man in California. Diagnosis was aided by plasma microbial cell-free DNA sequencing. We conclude that the infection was acquired in California.

BACKGROUND: Epidemics of dengue, chikungunya and Zika are a growing threat to areas where Aedes aegypti are present. The efficacy of chemical control of Ae. aegypti is threatened by the increasing frequency of insecticide resistance. The objective of this study was to determine the susceptibility status as well as the biochemical and molecular mechanisms underlying insecticide resistance in three populations of Ae. aegypti in high risk areas of dengue, chikungunya, and Zika in Peru. METHODS: Bioassays were conducted on adult Ae. aegypti to evaluate their susceptibility to insecticides used currently or historically for mosquito control in Peru, including six pyrethroids, three organophosphates and one organochlorine, in populations of Ae. aegypti from the districts of Chosica (Department of Lima), Punchana (Department of Loreto) and Piura (Department of Piura). Resistance mechanisms were determined by biochemical assays to assess activity levels of key detoxification enzyme groups (nonspecific esterases, multi-function oxidases, glutathione S-transferases and insensitive acetylcholinesterase). Real-time PCR assays were used to detect two kdr mutations (V1016I and F1534C) on the voltage-gated sodium channel gene. RESULTS: Resistance to DDT was detected in all three populations, and resistance to pyrethroids was detected in all populations except the population from Chosica, which still exhibited susceptibility to deltamethrin. Resistance to organophosphates was also detected, with the exception of populations from Punchana and Piura, which still demonstrated susceptibility to malathion. In general, no increase or alteration of activity of any enzyme group was detected. Both 1016I and 1534C alleles were detected in Punchana and Piura, while only the 1534C allele was detected in Chosica. CONCLUSIONS: The results suggest that resistance to multiple classes of insecticides exist in areas important to Ae. aegypti-borne disease transmission in Peru. The F1534C mutation was present in all 3 populations and the V1016I mutation was present in 2 populations. To our knowledge, this is the first report of the presence of 1016I and 1534C in Ae. aegypti in Peru. The absence of highly elevated enzymatic activity suggests that target site resistance is a key mechanism underlying insecticide resistance in these populations, although further research is needed to fully understand the role of metabolic resistance mechanisms in these populations.

In light of the declining global malaria burden attained largely due to insecticides, a deeper understanding of the factors driving insecticide resistance is needed to mitigate its growing threat to malaria vector control programs. Following evidence of microbiota-mediated insecticide resistance in agricultural pests, we undertook a comparative study of the microbiota in mosquitoes of differing insecticide resistance status. The microbiota of wild-caught Anopheles albimanus, an important Latin American malaria vector, that were resistant (FEN_Res) or susceptible (FEN_Sus) to the organophosphate (OP) insecticide fenitrothion were characterized and compared using whole metagenome sequencing. Results showed differing composition of the microbiota and its functions between FEN_Res and FEN_Sus, with significant enrichment of OP-degrading bacteria and enzymes in FEN_Res compared to FEN_Sus. Lower bacterial diversity was observed in FEN_Res compared to FEN_Sus, suggesting the enrichment of bacterial taxa with a competitive advantage in response to insecticide selection pressure. We report and characterize for the first time whole metagenomes of An. albimanus, revealing associations between the microbiota and phenotypic resistance to the insecticide fenitrothion. This study lays the groundwork for further investigation of the role of the mosquito microbiota in insecticide resistance.

In August 2015, plague was diagnosed for 2 persons who had visited Yosemite National Park in California, USA. One case was septicemic and the other bubonic. Subsequent environmental investigation identified probable locations of exposure for each patient and evidence of epizootic plague in other areas of the park. Transmission of Yersinia pestis was detected by testing rodent serum, fleas, and rodent carcasses. The environmental investigation and whole-genome multilocus sequence typing of Y. pestis isolates from the patients and environmental samples indicated that the patients had been exposed in different locations and that at least 2 distinct strains of Y. pestis were circulating among vector-host populations in the area. Public education efforts and insecticide applications in select areas to control rodent fleas probably reduced the risk for plague transmission to park visitors and staff.

BACKGROUND: Dengue is a major public health problem in Mexico, where the use of chemical insecticides to control the principal dengue vector, Aedes aegypti, is widespread. Resistance to insecticides has been reported in multiple sites, and the frequency of kdr mutations associated with pyrethroid resistance has increased rapidly in recent years. In the present study, we characterized patterns of insecticide resistance in Ae. aegypti populations in five small towns surrounding the city of Merida, Mexico. METHODS: A cross-sectional, entomological survey was performed between June and August 2013 in 250 houses in each of the five towns. Indoor resting adult mosquitoes were collected in all houses and four ovitraps were placed in each study block. CDC bottle bioassays were conducted using F0-F2 individuals reared from the ovitraps and kdr allele (Ile1016 and Cys1534) frequencies were determined. RESULTS: High, but varying, levels of resistance to chorpyrifos-ethyl was detected in all study towns, complete susceptibility to bendiocarb in all except one town, and variations in resistance to deltamethrin between towns, ranging from 63-88 % mortality. Significant associations were detected between deltamethrin resistance and the presence of both kdr alleles. Phenotypic resistance was highly predictive of the presence of both alleles, however, not all mosquitoes containing a mutant allele were phenotypically resistant. An analysis of genotypic differentiation (exact G test) between the five towns based on the adult female Ae. aegypti collected from inside houses showed highly significant differences (p < 0.0001) between genotypes for both loci. When this was further analyzed to look for fine scale differences at the block level within towns, genotypic differentiation was significant for both loci in San Lorenzo (Ile1016, p = 0.018 and Cys1534, p = 0.007) and for Ile1016 in Acanceh (p = 0.013) and Conkal (p = 0.031). CONCLUSIONS: The results from this study suggest that 3 years after switching chemical groups, deltamethrin resistance and a high frequency of kdr alleles persisted in Ae. aegypti populations. The spatial variation that was detected in both resistance phenotypes and genotypes has practical implications, both for vector control operations as well as insecticide resistance management strategies.

Interventions targeting adult mosquitoes are used to combat transmission of vector-borne diseases, including dengue. Without available vaccines, targeting the primary vector, Aedes aegypti, is essential to prevent transmission. Older mosquitoes (≥ 7 days) are of greatest epidemiological significance due to the 7-day extrinsic incubation period of the virus. Age-grading of female mosquitoes is necessary to identify post-intervention changes in mosquito population age structure. We developed models using near-infrared spectroscopy (NIRS) to age-grade adult female Ae. aegypti. To determine if diet affects the ability of NIRS models to predict age, two identical larval groups were fed either fish food or infant cereal. Adult females were separated and fed sugar water +/- blood, resulting in four experimental groups. Females were killed 1, 4, 7, 10, 13, or 16 days postemergence. The head/thorax of each mosquito was scanned using a near-infrared spectrometer. Scans from each group were analyzed, and multiple models were developed using partial least squares regression. The best model included all experimental groups, and positively predicted the age group (< or ≥ 7 days) of 90.2% mosquitoes. These results suggest both larval and adult diets can affect the ability of NIRS models to accurately assign age categories to female Ae. aegypti.

BACKGROUND: Resistance to multiple classes of insecticides has been detected in the malaria vector Anopheles albimanus in northwest Peru. Acetylcholinesterase (AChE) insensitivity has previously been associated with resistance to organophosphate (OP) and carbamate (CA) insecticides in arthropods. A single point mutation on the ace-1 gene (G119S) associated with resistance to OPs and CAs has been described previously in four anopheline species, but not in field-collected An. albimanus. The present study aimed to characterize the role of ace-1 in conferring resistance to both OPs and CAs in the An. albimanus population in Tumbes, Peru. METHODS: The frequency and intensity of resistance to OPs and CAs was quantified through bioassays of female An. albimanus collected between 2012 and 2014, and the presence of insensitive AChE was confirmed using biochemical assays. A portion of the ace-1 gene flanking codon 119 was amplified and sequenced from individuals used in the bioassays and biochemical assays, as well as from historical samples collected in 2008. Statistical analyses were conducted to determine: (1) associations between genotype and AChE insensitivity; and, (2) associations between genotype and resistance phenotype. RESULTS: After confirming high levels of resistance to fenitrothion, malathion, and bendiocarb through bioassays, two novel polymorphisms were identified at the first and second loci of codon 119, with all individuals from the 2012-2014 collections being heterozygous at the first base (G/T) and either heterozygous (G/C) or homozygous mutants (C/C) at the second base. Based on sequence data from historical samples, these mutations arose prior to 2008, but became fixed in the population between 2008 and 2012. Homozygotes at the second locus had significantly higher levels of AChE insensitivity than heterozygotes (p <0.05). Individuals phenotypically susceptible to OPs and CAs were more likely to be heterozygous at the second locus (p <0.01). Cloning identified four individuals each containing three distinct genotypes, suggesting that a duplication of the ace-1 gene may have occurred. CONCLUSIONS: The occurrence of heterozygotes at two loci and the presence of three genotypes in four individuals suggest that balancing selection could be maintaining OP and CA resistance in this population, while minimizing associated fitness costs.

BACKGROUND: Anopheles albimanus is a key malaria vector in the northern neotropics. Current vector control measures in the region are based on mass distributions of long-lasting insecticidal nets (LLINs) and focal indoor residual spraying (IRS) with pyrethroids. Resistance to pyrethroid insecticides can be mediated by increased esterase and/or multi-function oxidase activity and/or mutations in the voltage-gated sodium channel gene. The aim of this work was to characterize the homologous kdr region of the voltage-gated sodium channel gene in An. albimanus and to conduct a preliminary retrospective analysis of field samples collected in the 1990's, coinciding with a time of intense pyrethroid application related to agricultural and public health insect control in the region. METHODS: Degenerate primers were designed to amplify the homologous kdr region in a pyrethroid-susceptible laboratory strain (Sanarate) of An. albimanus. Subsequently, a more specific primer pair was used to amplify and sequence the region that contains the 1014 codon associated with pyrethroid resistance in other Anopheles spp. (L1014F, L1014S or L1014C). RESULTS: Direct sequencing of the PCR products confirmed the presence of the susceptible kdr allele in the Sanarate strain (L1014) and the presence of homozygous-resistant kdr alleles in field-collected individuals from Mexico (L1014F), Nicaragua (L1014C) and Costa Rica (L1014C). CONCLUSIONS: For the first time, the kdr region in An. albimanus is described. Furthermore, molecular evidence suggests the presence of kdr-type resistance in field-collected An. albimanus in Mesoamerica in the 1990s. Further research is needed to conclusively determine an association between the genotypes and resistant phenotypes, and to what extent they may compromise current vector control efforts.

BACKGROUND: Nearly one of every three workers in the United States is low-income. Low-income populations have a lower life expectancy and greater rates of chronic diseases compared to those with higher incomes. Low- income workers face hazards in their workplaces as well as in their communities. Developing integrated public health programs that address these combined health hazards, especially the interaction of occupational and non-occupational risk factors, can promote greater health equity. METHODS: We apply a social-ecological perspective in considering ways to improve the health of the low-income working population through integrated health protection and health promotion programs initiated in four different settings: the worksite, state and local health departments, community health centers, and community-based organizations. RESULTS: Examples of successful approaches to developing integrated programs are presented in each of these settings. These examples illustrate several complementary venues for public health programs that consider the complex interplay between work-related and non work-related factors, that integrate health protection with health promotion and that are delivered at multiple levels to improve health for low-income workers. CONCLUSIONS: Whether at the workplace or in the community, employers, workers, labor and community advocates, in partnership with public health practitioners, can deliver comprehensive and integrated health protection and health promotion programs. Recommendations for improved research, training, and coordination among health departments, health practitioners, worksites and community organizations are proposed. (Am. J. Ind. Med. (c) 2013 Wiley Periodicals, Inc.)

SHELLEY DAVIS MADE important contributions to civil rights, public health, and social justice, but, above all, she was a tireless advocate at the service of farmworkers. During her thirty-year career she fought in every available forum—federal and state courts, administrative agencies, state and federal legislatures, and the court of public opinion—over many issues, but especially over occupational health, environmental justice, child labor, and the rights of Latino and indigenous farmworkers. On Shelley Davis' CaringBridge Web site, Arturo S. Rodriguez, president of the United Farm Workers, wrote of her, “She is driven by an intense desire to ensure that the people who harvest the food we eat not be forced to sacrifice their health in the process.” | Davis, recognized and respected by allies and adversaries alike as a brilliant strategist in the area of social policy, was a masterful attorney who authored extraordinarily well-written and well-argued briefs. She was perhaps best known to her colleagues as an indefatigable and tenacious fighter for justice whose irrepressible optimism inspired others to join in her cause. Davis consistently fought to defend farmworkers, whether the matter was wage theft, pesticides, or HIV/AIDS. She was an authority not only on the law but also on public health issues. Davis was a bilingual (English and Spanish) activist personally involved with workers' lives and concerns. Her collaborator Nargess Shadbeh remembers that, in the field, Davis's first request was always, “Let's go to the labor camps so we can talk to the workers.”