February 5, 2016

EVERYTHING comes from somewhere. But where does the blacklegged tick relapsing fever germ Borrelia miyamotoi come from? Previous studies (Scott et al. 2010 J Med Entomol) found a high proportion of wild turkeys positive for B. miyamotoi infection in TN but none of the ticks found attached to the birds were positive for infection. Extremely low rates of infection in wild mice have been reported, also calling into question the role of rodents as reservoir for this germ (Barbour et al. 2009 Am J Trop Med Hyg). 

A new report by Han et al. (2016 Emerg Inf Dis) now shows that female blacklegged ticks removed from hunter-killed white-tailed deer in WI have a notably higher rate of B. miyamotoi infection (7.1%) than host seeking ticks in the same environment (1%). While this finding alone fails to provide conclusive proof of reservoir status, it’s certainly a call for additional controlled transmission studies with white-tailed deer and immature stages of blacklegged ticks.

Read full article on cdc.gov: http://wwwnc.cdc.gov/eid/article/22/2/15-1218_article