ABSTRACT
In February 2006, a diagnosis of sylvatic epidemic typhus in a counselor at a wilderness camp in Pennsylvania prompted a retrospective investigation. From January 2004 through January 2006, 3 more cases were identified. All had been counselors at the camp and had experienced febrile illness with myalgia, chills, and sweats; 2 had been hospitalized. All patients had slept in the same cabin and reported having seen and heard flying squirrels inside the wall adjacent to their bed. Serum from each patient had evidence of infection with Rickettsia prowazekii. Analysis of blood and tissue from 14 southern flying squirrels trapped in the woodlands around the cabin indicated that 71% were infected with R. prowazekii. Education and control measures to exclude flying squirrels from housing are essential to reduce the likelihood of sylvatic epidemic typhus.
Subject(s)
Sciuridae/microbiology , Typhus, Epidemic Louse-Borne/epidemiology , Adult , Animals , Disease Reservoirs , Education, Medical, Continuing , Humans , Interviews as Topic , Male , Pennsylvania , Rickettsia prowazekii/isolation & purification , Surveys and Questionnaires , Typhus, Epidemic Louse-Borne/complications , Typhus, Epidemic Louse-Borne/transmissionABSTRACT
Coxiella burnetii is a category B bioterrorism agent. We numerically evaluated the risks and benefits from postexposure prophylaxis (PEP) after an intentional release of C. burnetii to the general population, pregnant women, and other high-risk populations. For each group, we constructed a decision tree to estimate illness and deaths averted by use of PEP/100,000 population. We calculated the threshold points at which the number of PEP-related adverse events was equal to the cases averted. PEP was defined as doxycycline (100 mg 2x/day for 5 days), except for pregnant women, where we assumed a PEP of trimethoprim-sulfamethoxazole (160 mg/800 mg 2x/day) for the duration of the pregnancy. PEP would begin 8-12 days postexposure. On the basis of upper-bound probability estimates of PEP-related adverse events for doxycycline, we concluded that the risk for Q fever illness outweighs the risk for antimicrobial drug-related adverse events when the probability of C. burnetii exposure is >or=7% (pregnant women using trimethoprim-sulfamethoxazole = 16%).