Ticks rank with mosquitoes as the most important arthropod vectors of disease to humans and animals worldwide. In the western US, important tickborne diseases include Lyme disease and granulocytic anaplasmosis (caused by Anaplasma phagocytophilum) of humans, anaplasmosis (caused by A. marginale) and epizootic bovine abortion of cattle, ehrlichiosis of dogs, and anaplasmosis of horses. Internationally, ticks vector heartwater and babesiosis in cattle, tickborne rickettsiosis and tickborne encephalitis in humans, and other devastating problems that result in death, suffering and huge economic losses. Ticks may induce tick paralysis, directly cause blood-loss anemia, develop multi-drug resistance to the chemicals used to kill and control them, and be responsible for enormous eradication and control programs.
There are multiple projects at UC Davis in tickborne disease, depending on the interests and skills of the lead investigators or graduate students. Most projects focus on ecology and epidemiology of tickborne disease. Most ticks feed over the course of their lives on two or more different host species, so there are opportunities for interesting and complex ecologies. Studying such ecological problems requires expertise in field biology, theory, mammalogy, veterinary medicine, tick biology, bacteriology, and other disciplines. We work through local and international collaborations to acquire the needed expertise, including with Drs. Wuchun Cao and Jing He at the Beijing Institute for Microbiology and Epidemiology in the People's Republic of China, Dr. Bob Lane in the Division of Insect Biology at UC Berkeley, Dr. Rick Brown in the Department of Wildlife at Humboldt State University, Dr. Patrick Foley in the Department of Biological Sciences at California State University Sacramento, Dr. Steve Dumler at Johns Hopkins University, Dr. Joon Seuk Chae at Chonbuk National University in South Korea, and others.
Current ongoing projects include forest change and the emergence of disease transmitted by Ixodes ricinus group hard ticks in northern California and northeastern China (Foley lead investigator), spread and maintenance of EBA in cattle California and soft ticks (Teglas), modeling the enzootic maintenance of granulocytic anaplasmosis in California wildlife (J. Foley and P. Foley), understanding high anaplasmosis and Lyme-risk regions of far northern California through wildlife and tick studies (Brown and Foley), comparative habitat analysis for hard-tick borne disease in the western US (Nieto), and developing an active surveillance program for exotic ticks of cattle in California (Foley).