Potentially complicating the diagnosis and treatment of these diseases is the fact that ticks
may be infected with more than one agent. Recent research has shown blacklegged ticks in
New Jersey to be simultaneously co-infected with disease agents for both Lyme disease and
HGA (2.7-6.0%), Lyme disease and human babesiosis (2.0%), and HGA and human babesiosis
(2.0%). Lone star ticks have been shown to be co-infected with the infectious agents of HME
(4.1%) and both STARI and HME (0.8%).