667. An Emerging Tick-Borne Disease in Long Island, New York: Relapsing Fever Caused by Borrelia miyamotoi

BACKGROUND: Suffolk County (Long Island, New York) reports annually the highest absolute number of tick-borne diseases in New York. A new Borrelia species, Borrelia miyamotoi which causes a relapsing fever, has been reported in New York recently. The aim of this study was to identify the number of cases of B. miyamotoi diagnosed in Suffolk county. METHODS: A retrospective chart review was performed in Stony Brook (SB) Medicine hospitals, SB University Hospital (the only tertiary medical center in Suffolk County) and Southampton Hospital (a major hospital in the east end of Suffolk County). Laboratory records were queried for a positive B. miyamotoi PCR test from blood or a positive IgG antibody with a B. miyamotoi-specific EIA that utilizes a recombinant GlpQ antigen (both tests performed in a commercial laboratory). RESULTS: Twenty-eight cases were positive for serology (IgG EIA; n = 19) or PCR (n = 9). None of the IgG-positive cases had a positive PCR result indicating that individuals were likely exposed to B. miyamotoi in the past. Of the nine PCR-positive cases (median age:67 years), eight were men, three were diagnosed in the outpatient clinic (33.3%) and six were diagnosed through the emergency department and required hospitalization (66.6%). Thrombocytopenia and transaminitis were common findings. Two-thirds of these nine cases were diagnosed in the period of 2016–2017 and one-third in the period, 2013–2015 (P = 0.17). CONCLUSION: An increasing number of cases of B. miyamotoi were observed in Suffolk County during 2013–2017 and two-thirds required hospitalization. The real burden of this tick borne disease in Suffolk County and the rest of the state is unknown. DISCLOSURES: All authors: No reported disclosures.