Snapshot A middle-aged man returned from a camping trip in Northern California and found a tick clinging to his scalp. He removed the tick (shown here). About three days later, he presented with a headache, sudden and dramatic onset of chills, fever, and vomiting. The site of the tick bite was ulcerated, and the regional lymph nodes were enlarged. No rash was noted. Introduction Tularemia is a systemic, flu-like infection that usually appears 2-3 days after a tick bite Caused by the bacterium Francisella tularensis Transmitted to humans and domestic animals via contact with infected animal tissues deer ticks biting flies (i.e. horseflies) mosquito vectors aerosolized, contaminated dirt (especially on Martha's Vineyard) Life cycle bacteria enter skin form an ulcer at the site of entry localize to the cells of the reticuloendothelial system form granulomas that serve as reservoirs for bacterial growth Epidemiology most common reservoir for bacteria is infected rabbits disease most commonly occurs in North America and parts of Europe and Asia Presentation Symptoms symptoms appear following incubation period of 3-5 days after exposure onset is usually sudden at which point patients may experience fever chills conjunctivitis flu-like symptoms headaches muscle ache joint stiffness dyspnea weight loss diaphoresis ulcer/sore on skin at site of infection symptoms may persist for weeks following onset Physical exam painful lymphadenopathy others listed above Evaluation Blood cultures to identify Tularemia bacteria Serology to assess immune response CXR to identify and/or rule-out associated pneumonia from aerosolized exposure PCR from sample in ulcer may aid in identifying pathogen Differential Lyme disease, babesiosis, plague, Rickettsia, Rocky-mountain spotted fever, erhlichiosis Treatment Medical Management oral antibiotics streptomycin indicated as first-line therapy in most cases gentamicin has shown promising results in a few cases tetracycline and chloramphenicol not first-line therapy, due to high relapse rates Prognosis, Prevention, and Comlications Prognosis very good to excellent less than 5% of untreated cases are lethal; less than 1% of treated cases are lethal Prevention wear appropriate clothing when outdoors in endemic areas for vectors of disease Complications associated with pericarditis, osteomyelitis, meningitis, and pneumonia