1271. Changing Geographic Range of Primary Amebic Meningoencephalitis Minnesota, 2010
Session: Poster Abstract Session: Travel/Tropical Medicine and Parasitology
Saturday, October 22, 2011
Room: Poster Hall B1
  • Kemble_PAM in Minnesota_poster.pdf (830.1 kB)
  • Background: Primary amebic meningoencephalitis (PAM), a rare and nearly always fatal infection caused by the thermophilic ameba, Naegleria fowleri, is caused when the ameba travels up the nose to the brain after immersion in warm fresh water. Confirmed cases in the United States have been limited to southern-tier states. In August 2010, a female, aged 7 years, died; PAM was suspected on the basis of amebae observed in cerebrospinal fluid (CSF).

    Methods: Medical records were reviewed and the patient’s parents interviewed. Site investigations included environmental sampling where the patient had swum during the 2 weeks preceding illness onset. Patient and environmental samples were tested for N. fowleri by culture and polymerase chain reaction (PCR); isolates were genotyped. Historic local ambient temperature data were obtained.

    Results: The patient’s brain tissue and CSF tested positive for N. fowleri by culture and PCR. The patient had no travel or water exposures outside Minnesota. Water-related exposures included hours of swimming, including underwater handstands in 2 lakes (A and B) and 1 river in Washington County, Minnesota. N. fowleri was cultured and identified by PCR from water and sediment from Lake A only. N. fowleri isolates from brain, water, and sediment were all genotype 3. Surface water temperatures at Lake A ranged from 22.1ºC to 24.5ºC. August 2010 average air temperature near Lake A was 25°C, 3.6°C above normal and the third warmest for August since 1891.

    Conclusion: This is the most northern latitude PAM case identified in the United States by 550 miles. Changing climate patterns and elevated water temperatures require an elevated index of suspicion for PAM in geographic locations not historically considered to be an exposure risk.

    Subject Category: T. Travel/tropical medicine and parasitology

    Sarah Kemble, MD1,2, Govinda S. Visvesvara, PhD2, Ruth Lynfield, MD1, Aaron DeVries, MD, MPH1, Dennis Drehner, DO3, William Pomputius III, MD3, Michael Beach, PhD2, Alex da Silva, PhD2, Vincent Hill, PhD, PE2, Jonathan Yoder, MSW, MPH2, Lihua Xiao, PhD2, Kirk Smith, DVM, PhD1 and Richard Danila, PhD, MPH4, (1)Minnesota Department of Health, St. Paul, MN, (2)Centers for Disease Control and Prevention, Atlanta, GA, (3)Children's Hospitals and Clinics of Minnesota, Minneapolis, MN, (4)Infectious Disease Epidemiology Prevention and Control, Minnesota Department of Health, St. Paul, MN


    S. Kemble, None

    G. S. Visvesvara, None

    R. Lynfield, None

    A. DeVries, None

    D. Drehner, None

    W. Pomputius III, None

    M. Beach, None

    A. da Silva, None

    V. Hill, None

    J. Yoder, None

    L. Xiao, None

    K. Smith, None

    R. Danila, None

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.