Mosquito Surveillance Program Using Ovitraps Detected Aedes aegypti at the Honolulu International Airport in 2012

mosquito surveillance program using ovitraps at the Honolulu In- ternational Airport (HIA), Hawaii, USA May 2010 to June 2012 revealed that A. albopictus egg counts fluctuated over time during the surveillance program and the highest oviposition was observed from February to May 2011 and the lowest was from September to November 2011. Positive correlations found between a given week’s rainfall and egg counts 1 and 2 weeks later suggested that rainfall triggered the hatching of eggs which were laid before the rainfall, rather than di- rectly stimulating adult oviposition. In January and June 2012, Aedes aegypti was discovered from a small vegetated area located between terminals for out-of-state and within-state flights. This species had not been confirmed present on Oahu at least since 1948. This finding has led us to intensify our surveillance program at the airport, with the hope that we would improve our understanding of the nature of mosquito introductions at this important port of entry for the Hawaiian Islands

Tiger on the prowl: invasion history and spatio-temporal genetic structure of the Asian tiger mosquito Aedes albopictus (Skuse 1894) in the Indo-Pacific

Background: Within the last century, increases in human movement and globalization of trade have facilitated the establishment of several highly invasive mosquito species in new geographic locations with concurrent major environmental, economic and health consequences. The Asian tiger mosquito, Aedes albopictus, is an extremely invasive and aggressive daytime-biting mosquito that is a major public health threat throughout its expanding range. Methodology/Principal findings: We used 13 nuclear microsatellite loci (on 911 individuals) and mitochondrial COI sequences to gain a better understanding of the historical and contemporary movements of Ae. albopictus in the Indo-Pacific region and to characterize its population structure. Approximate Bayesian computation (ABC) was employed to test competing historical routes of invasion of Ae. albopictus within the Southeast (SE) Asian/Australasian region. Our ABC results show that Ae. albopictus was most likely introduced to New Guinea via mainland Southeast Asia, before colonizing the Solomon Islands via either Papua New Guinea or SE Asia. The analysis also supported that the recent incursion into northern Australia's Torres Strait Islands was seeded chiefly from Indonesia. For the first time documented in this invasive species, we provide evidence of a recently colonized population (the Torres Strait Islands) that has undergone rapid temporal changes in its genetic makeup, which could be the result of genetic drift or represent a secondary invasion from an unknown source. Conclusions/Significance: There appears to be high spatial genetic structure and high gene flow between some geographically distant populations. The species' genetic structure in the region tends to favour a dispersal pattern driven mostly by human movements. Importantly, this study provides a more widespread sampling distribution of the species' native range, revealing more spatial population structure than previously shown. Additionally, we present the most probable invasion history of this species in the Australasian region using ABC analysis

First Collection of Aedes japonicus (Theobald) (Diptera: Culicidae) on Oahu, Hawaii

A single adult female of Aedes japonicus (Theobald) was collected in a gravid trap at the Honolulu International Airport, Oahu, HI, on October 31, 2012. This is the first detection of Ae. japonicus on Oahu, Hawaii

Data from: Borrelia burgdorferi sensu lato spirochetes in wild birds in northwestern California: associations with ecological factors, bird behavior and tick infestation

Although Borrelia burgdorferi sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult Ixodes pacificus ticks and potential reservoirs of the Lyme disease spirochete B. burgdorferi sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 I. pacificus larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by I. pacificus with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of Borrelia bissettii in birds. Moreover, our data suggest that the Golden-crowned Sparrow (Zonotrichia atricapilla), a non-resident species, could be an important reservoir for B. burgdorferi s.s. Of 12 individual birds (9 species) that carried B. burgdorferi s.l.-infected larvae, no birds carried the same genospecies of B. burgdorferi s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of B. burgdorferi s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and Borrelia infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States

Borrelia burgdorferi sensu lato spirochetes in wild birds in northwestern California: associations with ecological factors, bird behavior and tick infestation.

Although Borrelia burgdorferi sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult Ixodes pacificus ticks and potential reservoirs of the Lyme disease spirochete B. burgdorferi sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 I. pacificus larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by I. pacificus with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of Borrelia bissettii in birds. Moreover, our data suggest that the Golden-crowned Sparrow (Zonotrichia atricapilla), a non-resident species, could be an important reservoir for B. burgdorferi s.s. Of 12 individual birds (9 species) that carried B. burgdorferi s.l.-infected larvae, no birds carried the same genospecies of B. burgdorferi s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of B. burgdorferi s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and Borrelia infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States

Borrelia Sequences Associated with Birds and Ticks

Sequence data from various Borrelia genospecies prepared in FASTA format

Bird and Tick Infection and Infestation data

These data represent all birds, Ixodes pacificus nymphs, and Ixodes pacificus larvae sampled in the associated study, and what Borrelia genospecies were found in each sample

<i>Borrelia burgdorferi</i> Sensu Lato Spirochetes in Wild Birds in Northwestern California: Associations with Ecological Factors, Bird Behavior and Tick Infestation

<div><p>Although <i>Borrelia burgdorferi</i> sensu lato (s.l.) are found in a great diversity of vertebrates, most studies in North America have focused on the role of mammals as spirochete reservoir hosts. We investigated the roles of birds as hosts for subadult <i>Ixodes pacificus</i> ticks and potential reservoirs of the Lyme disease spirochete <i>B. burgdorferi</i> sensu stricto (s.s.) in northwestern California. Overall, 623 birds representing 53 species yielded 284 <i>I. pacificus</i> larvae and nymphs. We used generalized linear models and zero-inflated negative binomial models to determine associations of bird behaviors, taxonomic relationships and infestation by <i>I. pacificus</i> with borrelial infection in the birds. Infection status in birds was best explained by taxonomic order, number of infesting nymphs, sampling year, and log-transformed average body weight. Presence and counts of larvae and nymphs could be predicted by ground- or bark-foraging behavior and contact with dense oak woodland. Molecular analysis yielded the first reported detection of <i>Borrelia bissettii</i> in birds. Moreover, our data suggest that the Golden-crowned Sparrow (<i>Zonotrichia atricapilla</i>), a non-resident species, could be an important reservoir for <i>B. burgdorferi</i> s.s. Of 12 individual birds (9 species) that carried <i>B. burgdorferi</i> s.l.-infected larvae, no birds carried the same genospecies of <i>B. burgdorferi</i> s.l. in their blood as were present in the infected larvae removed from them. Possible reasons for this discrepancy are discussed. Our study is the first to explicitly incorporate both taxonomic relationships and behaviors as predictor variables to identify putative avian reservoirs of <i>B. burgdorferi</i> s.l. Our findings underscore the importance of bird behavior to explain local tick infestation and <i>Borrelia</i> infection in these animals, and suggest the potential for bird-mediated geographic spread of vector ticks and spirochetes in the far-western United States.</p></div

Summary of <i>Ixodes pacificus</i> infestation on birds, <i>Borrelia burgdorferi</i> s.l. (BBSL) infection in bird blood, and number of BBSL infected larvae by bird species.

<p>Summary of <i>Ixodes pacificus</i> infestation on birds, <i>Borrelia burgdorferi</i> s.l. (BBSL) infection in bird blood, and number of BBSL infected larvae by bird species.</p

Summary of <i>B</i>. <i>burgdorferi</i> s.l. genospecies found in birds.

<p>Numbers in bold with an asterisk (*) indicate matching genospecies between individual bird and hosted ticks, for the indicated category. Acronyms in table are: BBSL, <i>B</i>. <i>burgdorferi</i> s.l; BBSS, <i>B</i>. <i>burgdorferi</i> sensu stricto; BBIS, <i>B</i>. <i>bissettii</i>; BBSL(un), undifferentiated genospecies in the <i>B</i>. <i>burgdorferi</i> sensu lato complex that are neither BBSS nor BBIS; and BBSLmix, any combination of BBSL(un), BBSS, and BBIS detected in a single sample.</p><p>Summary of <i>B</i>. <i>burgdorferi</i> s.l. genospecies found in birds.</p