NOV 28, 2015

New Tick-Borne Bacterium Discovered

WRITTEN BY: Kerry Evans

Austrian researchers discovered a new strain of bacteria in foxes. It is closely related to Candidatus Neoehrlichia and is likely transmitted by ticks.

Two varieties of Candidatus Neoehrlichia are known to be spread by ticks and cause illness. Ca. N. mikurensis was isolated from Ixodes ricinus ticks in 1999 and has since been shown to infect humans, dogs, badgers, bears, hedgehogs, and shrews. A second species, Ca. N. lotoris was found in raccoons in the United States. Infection with Ca. Neoehrlichia causes flu-like symptoms and can be treated with doxycycline. However, more severe cases cause thrombosis and embolism.

Other common tick-borne diseases include tick-borne encephalitis and Lyme disease. Tick-borne encephalitis is caused by the appropriately named “tick-borne encephalitis virus” (TBEV). TBEV is an RNA virus that is closely related to West Nile, yellow fever, and dengue fever viruses, all of which are transmitted by insect vectors. The fatality rate for TBEV is only around 1%, however, the disease can be quite severe, causing meningoencephalitis and myelitis. Vaccines for TBEV are available, but require multiple doses and boosters.

Lyme disease is probably the most well-known tick-borne disease. Lyme is caused by the spirochete bacterium Borrelia burgdorferi. It is transmitted by Ixodes scapularis, “blacklegged”, ticks and causes chronic disease if left untreated. Once infected, most people develop a “bulls-eye” rash at the tick bite site. Flu-like symptoms are common, but patients also develop swollen joints that can progress to “Lyme arthritis”.

The moral is, take care to protect yourself when outdoors. Wear long pants and sleeves when hiking and always check yourself for ticks!

Sources: Phys.org, CDC, MicrobeWiki, Wikipedia