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Japanese encephalitis virus (JEV) is a mosquito-borne virus primarily found in Asia and Australia and is one of the few with an associated human/animal vaccine. Swine are amplifying hosts and wading birds are reservoirs of JEV, while horses and humans are incidental hosts. The primary vector is Culex tritaeniorhynchus, a generalist blood feeder not found in the United States (US); secondary vectors (e.g., Cx. pipiens, Cx. quinquefasciatus, Aedes japonicus, Ae. vexans) are widespread in the US (including North Carolina [NC]). The risk of JEV to NC was investigated because of widespread swine production, human populations, bird hosts, and possible mosquito vectors; however, recommendations can also apply to other swine producing states and regions. A brief review was conducted to identify transmission competent arthropod vectors, vertebrate hosts, and vector-host interactions for JEV. NC and other areas may be at risk for JEV emergence because of factors such as active international trade, volume of swine production, permissive climate, and widespread occurrence of potential vector species. Improved knowledge of the spatial distribution of swine farms, tracking movement of live swine, assessment of vector competence/capacity and blood feeding habits of potential JEV vectors, investigation of a JEV sentinel surveillance system, and assessment of efficacy for current biosecurity and control measures is needed to protect public and veterinary health.

Zika virus (ZIKV) is primarily transmitted to humans by Aedes aegypti and Ae. albopictus. Vector&ndash, virus interactions influencing vector competence vary and depend on biological and environmental factors. A mosquito&rsquo, s chronological age may impact its immune response against virus infection. Insecticides, source reduction, and/or public education are currently the best defense against mosquitoes that transmit ZIKV. This study assessed the effects of a mosquito&rsquo, s chronological age at time of infection on its response to ZIKV infection. We exposed young (6&ndash, 7 d post-emergence) and old (11&ndash, 12 d post-emergence) Ae. albopictus to a sublethal dose of bifenthrin prior to oral exposure to blood meals containing ZIKV (7-day incubation period). Old mosquitoes experienced a significantly (p &lt, 0.01) higher rate of mortality than young mosquitoes. Significantly higher ZIKV body titers (p &lt, 0.01) were observed in the old control group compared to the young control group. Significantly higher (p &lt, 0.01) ZIKV dissemination rates and leg titers (p &lt, 0.01) were observed in old bifenthrin-exposed mosquitoes compared to old control mosquitoes or young bifenthrin-exposed or control mosquitoes. Hence, bifenthrin exposure may increase the potential for virus transmission, however, the degree of these impacts varies with mosquito age. Impacts of insecticides should be considered in risk assessments of potential vector populations.

Improvements to risk assessments are needed to enhance our understanding of tick-borne disease epidemiology. We review tick vectors and duration of tick attachment required for pathogen transmission for the following pathogens/toxins and diseases: (1) Anaplasma phagocytophilum (anaplasmosis); (2) Babesia microti (babesiosis); (3) Borrelia burgdorferi (Lyme disease); (4) Southern tick-associated rash illness; (5) Borrelia hermsii (tick-borne relapsing fever); (6) Borrelia parkeri (tick-borne relapsing fever); (7) Borrelia turicatae (tick-borne relapsing fever); (8) Borrelia mayonii; (9) Borrelia miyamotoi; (10) Coxiella burnetii (Query fever); (11) Ehrlichia chaffeensis (ehrlichiosis); (12) Ehrlichia ewingii (ehrlichiosis); (13) Ehrlichia muris; (14) Francisella tularensis (tularemia); (15) Rickettsia 364D; (16) Rickettsia montanensis; (17) Rickettsia parkeri (American boutonneuse fever, American tick bite fever); (18) Rickettsia ricketsii (Rocky Mountain spotted fever); (19) Colorado tick fever virus (Colorado tick fever); (20) Heartland virus; (21) Powassan virus (Powassan disease); (22) tick paralysis neurotoxin; and (23) Galactose-α-1,3-galactose (Mammalian Meat Allergy-alpha-gal syndrome). Published studies for 12 of the 23 pathogens/diseases showed tick attachment times. Reported tick attachment times varied (