Variation in the Microbiota of Ixodes Ticks with Regard to Geography, Species, and Sex

Abstract

n Ixodes scapularis is the principal vector of Lyme disease on the East Coast and in the upper Midwest regions of the UnitedStates, yet the tick is also present in the Southeast, where Lyme disease is absent or rare. A closely related species, I. affinis, also carries the pathogen in the South but does not seem to transmit it to humans. In order to better understand the geographic diversity of the tick, we analyzed the microbiota of 104 adult I. scapularis and 13 adult I. affinis ticks captured in 19 locations in South Carolina, North Carolina, Virginia, Connecticut, and New York. Initially, ticks from 4 sites were analyzed by 454 pyrosequencing. Subsequently, ticks from these sites plus 15 others were analyzed by sequencing with an Illumina MiSeq machine. By both analyses, the microbiomes of female ticks were significantly less diverse than those of male ticks. The dissimilarity between tick microbiomes increased with distance between sites, and the state in which a tick was collected could be inferred from its microbiota. The genus Rickettsia was prominent in all locations. Borrelia was also present in most locations and was present at especially high levels in one site in western Virginia. In contrast, members of the family Enterobacteriaceae were very common in North Carolina I. scapularis ticks but uncommon in I. scapularis ticks from other sites and in North Carolina I. affinis ticks. These data suggest substantial variations in the Ixodes microbiota in association with geography, species, and sex.

Effects of temperature on bacterial microbiome composition in Ixodes scapularis ticks

“…In addition, they carry numerous endosymbionts and commensals, which may provide nutrient supplements to the tick and also affect vector competence (reviewed in (Narasimhan & Fikrig, ; Bonnet et al., ; Clay & Fuqua, )). Studies have reported that the tick microbial community is variable depending on several factors such as source of host blood meal (Rynkiewicz, Hemmerich, Rusch, Fuqua, & Clay, ), feeding status (Menchaca et al., ; Swei & Kwan, ; Zhang et al., ), tick species, life stage, gender, and geographical origin (Carpi et al., ; Van Treuren et al., ; Williams‐Newkirk, Rowe, Mixson‐Hayden, & Dasch, ). However, very few studies have focused on the tick microbiome differences based on environmental conditions such as seasons of collection (Lalzar, Harrus, Mumcuoglu, & Gottlieb, ) or the immediate environment (Menchaca et al., ).…”

Microbiome changes through ontogeny of a tick pathogen vector

“…; Van Treuren et al . ). Although the role of the blacklegged tick as a vector of the Lyme disease spirochete ( Borrelia burgdorferi ) and the babesiosis protozoan ( Babesia microti ) has been known since the late 1970s (Spielman ; Steere et al .…”

“…; Van Treuren et al . ), while only a few have examined specific tissues and organs (Andreotti et al . ; Budachetri et al .…”

Mosquito Microbiome Dynamics, a Background for Prevalence and Seasonality of West Nile Virus

“…The microbiota modifies the ability of a host to be affected by, and to transmit, pathogens. Thus, understanding the relationship between microbiota and arthropod disease vectors, including mosquitoes, may impact mitigation of emerging infectious diseases (Dennison et al, 2014; Van Treuren et al, 2015). …”