During January 2–February 8, the boy was exposed to six hamsters
that his family had purchased from a pet store in the Denver metropolitan
area. Each hamster reportedly died from “wet tail disease” (i.e.,
diarrhea) within 1 week of purchase. One hamster bit the child on the left
ring finger shortly before it died. Seven days later, the child had fever,
malaise, painful left axillary lymphadenopathy, and skin sloughing at the
bite site. After treatment with amoxicillin clavulanate failed, the patient
underwent excisional biopsy of a left axillary lymph node 49 days after symptom
onset for persistent painful lymphadenopathy and intermittent fever. Tissue
culture yielded a suspected Francisella tularensis isolate,
which was confirmed by real-time polymerase chain reaction and timed-release
fluorescence at the CDPHE laboratory. Convalescent serology was positive at
a titer of 4,096, and the isolate was identified by CDC as type B. No other
risk factors for tularemia exposure were identified, including no other animal
contact, no exposure to game meat, and no known mosquito, tick, or fly bites.
The patient improved after treatment with ciprofloxacin.