Powassan Meningoencephalitis, New York, New York, USA

Simon Sung¹

, Alysse G. Wurcel¹, Susan Whittier, Karen Kulas, Laura D. Kramer, Robin Flam, James Kirkland Roberts, and Simon Tsiouris

Author affiliations: Columbia University, New York City, New York, USA (S. Sung, A.G. Wurcel, S. Whittier, R. Flam, J.K. Roberts, S. Tsiouris); Tufts Medical Center, Boston, Massachusetts, USA (A.G. Wurcel); New York State Department of Health, Albany, New York, USA (K. Kulas, L.D. Kramer); Mid Hudson Medical Group, Hopewell Junction, New York, USA (R. Flam)

Abstract

Disease caused by Powassan virus (POWV), a tick-borne flavivirus, ranges from asymptomatic to severe neurologic compromise and death. Two cases of POWV meningoencephalitis in New York, USA, highlight diagnostic techniques, neurologic outcomes, and the effect of POWV on communities to which it is endemic.

Powassan virus (POWV), a rare neuroinvasive arbovirus, was first described in 1958 (1,2). POWV has been isolated from Ixodes ticks; implicated hosts include woodchucks, red squirrels, chipmunks, groundhogs, and white-footed mice (1–4). Symptoms of infection vary from mild myalgia to acute flaccid paralysis and neurologic involvement. In the United States, POWV has been reported in northeastern and north-central states, and incidence is increasing (3,4). We describe the clinical characteristics and outcomes of 2 patients with POWV in New York, New York, USA.

Case Reports

Case 1

In mid-February 2009, a 22-year-old man with a remote history of Lyme disease (LD) was transferred to Columbia University New York Presbyterian Hospital (CUNYPH) after an extensive work-up for aseptic meningitis. On December 20, 2008, he had flown home to eastern Long Island, New York, from Colorado. Sore throat and influenzaa-like symptoms developed, and he sought care from a local physician in early January. Rapid strep test result was negative, but oral cephalosporin was prescribed. His symptoms improved, and he returned to Colorado. Approximately 2 weeks later, symptoms recurred, along with fever, eye pain, lateral gaze palsy, ataxia, dysarthria, stomach pain, and neck stiffness. After visiting the student health center, he was admitted to a local hospital in early February. Results of blood tests were within normal limits; cerebrospinal fluid (CSF) contained 212 leukocyte/μL (reference 0–5 cells/μL) (95% lymphocytes), 0 erythrocytes/μL (reference 0/μL), protein 55 mg/dL (reference 15–60 mg/dL), and glucose 60 mg/dL (reference 50–80 mg/dL). He received intravenous ceftriaxone and acyclovir, improved slightly, and was discharged after 1 week. He returned to New York and was admitted to a local hospital 1 week after discharge with persistent neurologic signs. Repeat CSF analyses showed 59 leukocytes/μL (100% lymphocytes); given concern about LD, he was placed on ceftriaxone until LD serologic results were negative. All other PCRs and serologic work-ups for infectious agents were negative (Technical Appendix, Table