HUMAN BABESIOSIS IN NEW-YORK-STATE - REVIEW OF 139 HOSPITALIZED CASESAND ANALYSIS OF PROGNOSTIC FACTORS

Background: Babesiosis infections are infrequent, occur in limited geo graphic locations, and range from asymptomatic infection to severe ill ness and death. Methods: Descriptive clinical and epidemiological info rmation on human babesiosis cases was collated from state communicable disease reports and medical records of patients hospitalized from 198 2 to 1993. Univariate and multivariate analyses were performed to dete rmine prognostic factors associated with severe disease outcome (hospi talization ending in death, duration of hospitalization >14 days, or i ntensive care unit stay >2 clays). Results: Between 1982 and 1993, 139 patients were hospitalized with babesiosis in New York State. Nine pa tients (6.5%) died, 35 (25.2%) were admitted to the intensive care uni t, and 35 (25.2%) required hospitalization for more than 14 days. Mean age at first hospitalization was 62.5 years. Sixty-two percent were m ale, and 91% resided in Suffolk County, Long Island. The most common s ymptoms were fatigue/malaise/weakness (91%), fever (91%), shaking chil ls (77%), and diaphoresis (69%). Past medical records showed that 52% of patients had a history of chronic disease; 12% had a history of Lym e disease; 12% had undergone a splenectomy; and 2% had undergone a blo od transfusion. There was a 12- to 14-day delay between onset of sympt oms and initiation of appropriate antibiotic treatment. Univariate ana lyses showed alkaline phosphatase levels greater than 125 U/L, white b lood cell counts greater than 5 x 10(9)/L, history of cardiac abnormal ity, history of splenectomy, presence of heart murmur, and parasitemia values of 0.04 or higher to be significantly associated with disease severity. Multiple logistic regression analyses indicated that male se x, alkaline phosphatase values greater than 125 U/L, and white blood c ell counts greater than 5 x 109/L remained strong predictors of severe outcome. Conclusions: Human babesiosis is a rare but debilitating and potentially fatal illness, especially in the elderly. Prompt disease diagnosis and treatment are essential but are often delayed, as seen i n our series. This delay reinforces the need for enhanced public and p hysician education targeted toward residents and visitors to the few h igh-risk geographic areas where disease and Ixodes scapularis ticks ar e endemic. Patients presenting with certain prognostic indicators (mal e sex, alkaline phosphatase values >125 U/L, and white blood cell coun ts >5 x 109/L) require comprehensive and aggressive medical care to pr event further deterioration. Since babesiosis is only 1 of 3 currently recognized diseases transmitted by I scapularis ticks, primary preven tion recommendations will also reduce human exposure to Lyme disease a nd human granulocytic ehrlichiosis.