White‐Tailed Deer (Odocoileus virginianus) as a Potential Sentinel for Human Lyme Disease in Indiana

Abstract

Summary We assessed the potential of white‐tailed deer (WTD) (Odocoileus virginianus) to be a sentinel for human cases of Lyme disease (LD) in Indiana using location data from a 3‐year survey of approximately 3400 hunted deer with associated tick Ixodes scapularis and Borrelia burgdorferi (Bb) data. Data on human LD cases at the county level were obtained from the Indiana Department of Health. All data were assigned to county centroids to match the resolution of the LD data before creating optimized trend surfaces for LD incidence, hunted deer count, Ixodes scapularis and Bb prevalence. To determine whether LD was spatially associated with the areas of high densities of deer, deer with Ixodes scapularis and deer with ticks infected with Bb, we used spatial analysis with distance indices (SADIE). The SADIE analysis found significant spatial association between LD and the distribution of three organismal predictor variables, that is, WTD, Ixodes ticks and Bb. Lyme disease incident rate varied between 0.08 cases per 10 000 habitants (Johnson county) and 5.9 cases per 10 000 habitants (Warren county). In conclusion, WTD can be used as an accurate and cost‐effective sentinel for human LD. This method will permit public health workers to identify potentially endemic areas independently of human case reports.

County-Scale Distribution ofIxodes scapularisandIxodes pacificus(Acari: Ixodidae) in the Continental United States

“…Given the lack of systematic surveillance for I. scapularis , one might ask if the range expansion suggested by our data is real or merely an artifact of enhanced tick surveillance and research activities in some areas. A true range expansion of I. scapularis in northern states, as described in this report, is supported by the largely concordant changes in the distribution of human Lyme disease cases captured through mandatory reporting of the disease since 1991 (Rand et al 2007, Raizman et al 2012, Lee et al 2013, Serra et al 2013, Brinkerhoff et al 2014, Robinson et al 2014, Wang et al 2014, Kugeler et al 2015, Mead 2015). Moreover, as detailed later in the text, true range expansions of I. scapularis have been documented in some areas where tick surveillance was conducted routinely during the period of emergence, or where extensive surveys were conducted at discrete time-points spanning periods from when the tick was absent through invasion and establishment.…”

“…Populations of I. scapularis in the extreme northeast along the Illinois River speculatively may have originated from established populations in northwestern Indiana (Cortinas and Kitron 2006). In Indiana, where I. scapularis was first collected from deer in northwestern counties in 1987 (Pinger and Glancy 1989), densities of I. scapularis are greatest along the western border and decrease eastward; expansion to eastern counties was observed between 2005 and 2007 (Pinger et al 1996, Keefe 2008, Raizman et al 2012). …”

Target validation of highly conserved Amblyomma americanum tick saliva serine protease inhibitor 19

“…For instance, white tailed deer is the major blood meal source for A. americanum and Ixodes scapularis , the two medically important tick species that transmit 9 of the 14 reportable human TBD agents listed by USA Centers for Disease Control (www.cdc.gov). There is evidence that deer populations were associated with human cases of TBDs in several localities around in the USA (Piesman et al, 1979, Nieto et al, 2012, Raizman et al, 2013, Wiznia et al, 2013, Mays et al, 2014). In the US livestock industry, the threat of R. microplus and R. annulatus including its vectored deadly Babesia cattle parasites have been eradicated for more than 50 years (Walker, 2011, Giles et al, 2014).…”

Red oak seedlings as indicators of deer browse pressure: Gauging the outcome of different white‐tailed deer management approaches

“…Despite repeated calls to adopt accountability and good governance principles in more holistic stewardship and wildlife management (Decker et al, ; Hare & Blossey, ; Leopold et al, ), agencies continue to focus largely on interests of stakeholders who buy hunting and fishing licenses. Our own experience and the overwhelming scientific evidence for the primary role of deer in the deterioration of ecological, economic, and health of our landscapes in the presence of recreational hunting (Côté et al, ; Kelly, ; Kilpatrick et al, ; Miller & McGill, ; Nuttle et al, ; Raizman et al, ) does not bode well for the future, unless major changes are implemented.…”