TY - JOUR
T1 - Host, habitat and climate preferences of Ixodes angustus (Acari
T2 - Ixodidae) and infection with Borrelia burgdorferi and Anaplasma phagocytophilum in California, USA
AU - Stephenson, Nicole
AU - Wong, Johnny
AU - Foley, Janet E
PY - 2016/10/1
Y1 - 2016/10/1
N2 - The Holarctic tick Ixodes angustus is a competent vector for Borrelia burgdorferi, the etiologic agent of Lyme disease, and possibly Anaplasma phagocytophilum, the etiologic agent of granulocytic anaplasmosis, as well. From 2005 to 2013, we collected host-feeding I. angustus individuals from live-trapped small mammals and by flagging vegetation from 12 study sites in northern and central California, and tested for B. burgdorferi sensu lato, A. phagocytophilum, and Rickettsia spp. DNA by real-time PCR. Among 261 I. angustus collected (259 from hosts and two by flagging), the most common hosts were tree squirrels (20 % of ticks) and chipmunks (37 %). The PCR-prevalence for A. phagocytophilum and B. burgdorferi in ticks was 2 % and zero, respectively. The minimum infection prevalence on pooled DNA samples was 10 % for Rickettsia spp. DNA sequencing of the ompA gene identified this rickettsia as Candidatus Rickettsia angustus, a putative endosymbiont. A zero-inflated negative binomial mixed effects model was used to evaluate geographical and climatological predictors of I. angustus burden. When host species within study site and season within year were included in the model as nested random effects, all significant variables revealed that I. angustus burden increased as temperature decreased. Together with published data, these findings suggest that I. angustus is a host generalist, has a broad geographic distribution, is more abundant in areas with lower temperature within it’s range, and is rarely infected with the pathogens A. phagocytophilum and B. burgdorferi.
AB - The Holarctic tick Ixodes angustus is a competent vector for Borrelia burgdorferi, the etiologic agent of Lyme disease, and possibly Anaplasma phagocytophilum, the etiologic agent of granulocytic anaplasmosis, as well. From 2005 to 2013, we collected host-feeding I. angustus individuals from live-trapped small mammals and by flagging vegetation from 12 study sites in northern and central California, and tested for B. burgdorferi sensu lato, A. phagocytophilum, and Rickettsia spp. DNA by real-time PCR. Among 261 I. angustus collected (259 from hosts and two by flagging), the most common hosts were tree squirrels (20 % of ticks) and chipmunks (37 %). The PCR-prevalence for A. phagocytophilum and B. burgdorferi in ticks was 2 % and zero, respectively. The minimum infection prevalence on pooled DNA samples was 10 % for Rickettsia spp. DNA sequencing of the ompA gene identified this rickettsia as Candidatus Rickettsia angustus, a putative endosymbiont. A zero-inflated negative binomial mixed effects model was used to evaluate geographical and climatological predictors of I. angustus burden. When host species within study site and season within year were included in the model as nested random effects, all significant variables revealed that I. angustus burden increased as temperature decreased. Together with published data, these findings suggest that I. angustus is a host generalist, has a broad geographic distribution, is more abundant in areas with lower temperature within it’s range, and is rarely infected with the pathogens A. phagocytophilum and B. burgdorferi.
KW - Anaplasma phagocytophilum
KW - Borrelia burgdorferi
KW - Ecology
KW - Human granulocytic ehrlichiosis
KW - Lyme disease
KW - Ticks
UR - http://www.scopus.com/inward/record.url?scp=84978924379&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84978924379&partnerID=8YFLogxK
U2 - 10.1007/s10493-016-0068-8
DO - 10.1007/s10493-016-0068-8
M3 - Article
C2 - 27416728
AN - SCOPUS:84978924379
VL - 70
SP - 239
EP - 252
JO - Experimental and Applied Acarology
JF - Experimental and Applied Acarology
SN - 0168-8162
IS - 2
ER -