Relative Efficiency of Drag Fabrics for Collection of Blacklegged Tick (Acari: Ixodidae) Larvae, Nymphs, and Adults.

The blacklegged tick (Ixodes scapularis Say) vectors several bacterial, protozoan, and viral human pathogens. The known distribution, abundance, and phenology of I. scapularis within its estimated range are incomplete. This gap in knowledge is problematic because these factors are important for determining acarological risk of exposure to infected ticks. Consequently, enhanced surveillance of I. scapularis is being promoted and supported in the United States. Although the most common method for collecting I. scapularis is by dragging a sturdy cloth along the ground, there are no published empirical data showing which drag fabric is most effective. We used a randomized block design to directly compare the relative efficiencies of canvas, corduroy, and flannel drags for the collection of larval, nymphal, and adult I. scapularis. Overall, flannel was the most effective fabric and canvas was the least effective. Significantly more adults were collected on flannel than on canvas or corduroy, and the same number of nymphs was collected on flannel and corduroy. Significantly more larvae were collected on flannel than on canvas, but one-third of larvae could not be removed from the former fabric by lint-rolling, and handpicking was difficult. Our findings support the use of flannel drags to maximize sampling effort for collection of I. scapularis, especially adults to determine the presence of ticks and tick-borne pathogens when density and infection prevalence are low, with the caveat that detection and removal of larvae are time-consuming.

Lyme Disease Risk of Exposure to Blacklegged Ticks (Acari: Ixodidae) Infected with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) in Pittsburgh Regional Parks.

Lyme disease is the most commonly reported vector-borne illness and sixth most commonly reported notifiable infectious disease in the United States. The majority of cases occur in the Northeast and upper-Midwest, and the number and geographic distribution of cases is steadily increasing. The blacklegged tick (Ixodes scapularis Say) is the principal vector of the Lyme disease spirochete (Borrelia burgdorferi sensu stricto) in eastern North America. Although Lyme disease risk has been studied in residential and recreational settings across rural to urban landscapes including metropolitan areas, risk within U.S. cities has not been adequately evaluated despite the presence of natural and undeveloped public parkland where visitors could be exposed to B. burgdorferi-infected I. scapularis. We studied the occurrence of I. scapularis and infection prevalence of B. burgdorferi in four insular regional parks within the city of Pittsburgh to assess Lyme disease risk of exposure to infected adults and nymphs. We found that the density of I. scapularis adults (1.16 ± 0.21 ticks/100 m2) and nymphs (3.42 ± 0.45 ticks/100 m2), infection prevalence of B. burgdorferi in adults (51.9%) and nymphs (19.3%), and density of infected adults (0.60 ticks/100 m2) and nymphs (0.66 ticks/100 m2) are as high in these city parks as nonurban residential and recreational areas in the highly endemic coastal Northeast. These findings emphasize the need to reconsider, assess, and manage Lyme disease risk in greenspaces within cities, especially in high Lyme disease incidence states.

First Record of Aedes albopictus (Diptera: Culicidae) and Second Record of Aedes japonicus (Diptera: Culicidae) Parasitized by Water Mites (Acari: Hydrachnidiae) in North America.

The primary aim of this study was to determine if the Asian tiger mosquito (Aedes albopictus (Skuse)) (Diptera: Culicidae), that vectors a number of arboviruses, is parasitized by water mites (Acari: Prostigmata: Parasitengonina: Hydrachnidiae). Larval water mite parasitism of adult mosquitoes has been shown to reduce mosquito fecundity and life span in the laboratory, and impact some populations in the field. Water mites have been considered for biocontrol purposes and used to age-grade mosquito populations. Consequently, there is interest in water mite-mosquito associations from public health and integrated pest management perspectives. In 2016, the Pennsylvania Department of Environmental Protection West Nile Virus Control Program examined 146,607 mosquitoes representing 31 species for parasitic mites. Ten mosquitoes representing four species rarely or not previously known to be parasitized by mites were saved from destructive West Nile virus and Zika virus testing. Twelve parasitic mites were identified to the lowest taxonomic level possible. An Asian tiger mosquito and an Asian bush mosquito (Aedes japonicus) (Theobald) were each parasitized by a Parathyas sp. Lundblad (Hydryphantoidea: Hydryphantidae: Euthyadinae) water mite, and are the first and second records of these associations in North America, respectively. Two Culex restuans Theobald (Diptera: Culicidae) mosquitoes parasitized by either a Euthyas sp. Piersig (Hydryphantoidea: Hydryphantidae: Euthyadinae) or a Parathyas sp. water mite are new associations, and a Culex pipiens Linnaeus mosquito parasitized by a Parathyas sp. water mite represents a new record for this association in North America.