Tick paralysis: 33 human cases in Washington State, 1946-1996

Tick paralysis is a preventable cause of illness and death that, when diagn osed promptly, requires simple, low-cost intervention (tick removal). We re viewed information on cases of tick paralysis that were reported to the Was hington State Department of Health (Seattle) during 1946-1996. Thirty-three cases of tick paralysis were identified, including 2 in children who died, Most of the patients were female (76%), and most cases (82%) occurred in c hildren aged <8 years, Nearly all cases with information on site of probabl e exposure indicated exposure east of the Cascade Mountains. Onset of illne ss occurred from March 14 to June 22. Of the 28 patients for whom informati on regarding hospitalization was available, 54% were hospitalized. Dermacen tor andersoni was consistently identified when information on the tick spec ies was reported. This large series of cases of tick paralysis demonstrates the predictable epidemiology of this disease. Improving health care provid er awareness of tick paralysis could help limit morbidity and mortality due to this disease.