Friday, June 12, 2015

Prevalence of Bb in adult female I. scapularis, Wisconsin 2010


Mon Jun 8, 2015 6:41 am (PDT) . Posted by: 

"Rick Laferriere" ri_lymeinfo 

*Prevalence of /Borrelia burgdorferi/ in adult female ticks 
(/Ixodes scapularis/), Wisconsin 2010–2013*
Lloyd W. Turtinen, Alyssa N. Kruger and Madeleine M. Hacker
/Journal of Vector Ecology/, Volume 40, Issue 1, pages 
195-197, June 2015.

http://doi.org/10.1111/jvec.12152

The incidence of Lyme disease in some areas of Wisconsin, 
U.S.A. has more than tripled since 1991. Tick abundance and 
the prevalence of /Borrelia burgdorferi/ in questing ticks 
are essential components of risk assessment for Lyme disease 
borreliosis.

Published surveys completed overseas in various countries 
(Germany, Japan, China, Norway) have shown prevalence rates 
of /Borrelia/ spp. infection ranging from about 30-40% in 
adult /Ixodes/ spp. In Wisconsin, unpublished surveys also 
reveal that as many as 40-50% of /Ixodes scapularis/ adults 
in some areas may be infected. In recently published studies 
from the eastern United States, prevalence rates of /B. 
burgdorferi/ in adult /I. scapularis/ ranged from 27% to 
45.2%. In Wisconsin, the prevalence of /B. burgdorferi/ in 
/I. scapularis/ nymphs collected from managed red pine 
forests from 2009 to 2013 was approximately 30%.

To estimate the prevalence of adult questing ticks carrying 
the Lyme disease bacterium in this pilot study, we randomly 
collected 341 questing adult female /Ixodes scapularis/ from 
known and suspected tick habitats throughout regions of 
Wisconsin during the springs of 2010 through 2013. Nymphal 
and adult tick activity has been reported to be the highest 
in May and June. These locations generally were wooded with 
a medium-dense tree canopy and contained leaf litter. Sites 
with tall grasses on the wooded edges with agricultural 
plains were also chosen. The extent of urbanization was not 
recorded but in general was minimal.

Ticks were collected by walking the sampling area and 
removing ticks from the collector's clothing or using a 
flannel drag cloth. The same sites were not necessarily 
sampled each year as different individuals did the sampling 
each year in order to maximize the number of sampling 
locations (average of 24 sites each year). Ticks were 
collected from 21 counties in primarily west-central 
Wisconsin. Only adult female ticks (no nymphs or adult 
males) were assayed in this study.

http://doi.org/10.1111/jvec.12152

Free, full text (pdf file, 342 KB):
http://onlinelibrary.wiley.com/doi/10.1111/jvec.12152/epdf

No comments:

Post a Comment

Please be constructive in your comments.