The detection of monkeypox in humans in the Western Hemisphere.

BACKGROUND: During May and June 2003, an outbreak of febrile illness with vesiculopustular eruptions occurred among persons in the midwestern United States who had had contact with ill pet prairie dogs obtained through a common distributor. Zoonotic transmission of a bacterial or viral pathogen was suspected. METHODS: We reviewed medical records, conducted interviews and examinations, and collected blood and tissue samples for analysis from 11 patients and one prairie dog. Histopathological and electron-microscopical examinations, microbiologic cultures, and molecular assays were performed to identify the etiologic agent. RESULTS: The initial Wisconsin cases evaluated in this outbreak occurred in five males and six females ranging in age from 3 to 43 years. All patients reported having direct contact with ill prairie dogs before experiencing a febrile illness with skin eruptions. We found immunohistochemical or ultrastructural evidence of poxvirus infection in skin-lesion tissue from four patients. Monkeypox virus was recovered in cell cultures of seven samples from patients and from the prairie dog. The virus was identified by detection of monkeypox-specific DNA sequences in tissues or isolates from six patients and the prairie dog. Epidemiologic investigation suggested that the prairie dogs had been exposed to at least one species of rodent recently imported into the United States from West Africa. CONCLUSIONS: Our investigation documents the isolation and identification of monkeypox virus from humans in the Western Hemisphere. Infection of humans was associated with direct contact with ill prairie dogs that were being kept or sold as pets.

Monkeypox: an epidemiologic and clinical comparison of African and US disease.

Monkeypox is a double-stranded DNA virus and a member of the genus Orthopoxvirus. Human monkeypox was first identified in the Democratic Republic of the Congo (formerly Zaire) in 1970. The first outbreak in the western hemisphere occurred in the spring of 2003. Important epidemiologic and clinical differences exist between human monkeypox in the United States and in Africa, including sex distribution, case fatality, morphology of skin lesions, and associated lymphadenopathy. These divergent clinical presentations could be caused by mode of transmission (skin inoculation vs ingestion), the skin color of affected patients, the training backgrounds of those who saw and documented disease outbreaks, the virulence of monkeypox strains involved, nutritional status, access to advanced medical care, and the prevalence of prior smallpox vaccinations.

Characteristics of diagnosed polymorphous light eruption.

BACKGROUND: The characteristics of polymorphous light eruption (PMLE) have been described in patients evaluated and diagnosed at specialized photodermatology centers. Our goal was to describe the characteristics of PMLE diagnosed in a general clinic setting. METHODS: We used electronic medical records to identify patients diagnosed with PMLE from 2000 to 2002 within a large group practice. We then collected additional information from medical records about patient demographics, lesion morphology, diagnostic testing, and therapies for the selected patients. RESULTS: We identified 142 patients with diagnosed PMLE. After manual chart review, we excluded 18 patients with other forms of photosensitivity, eczema, or collagen vascular disease. Eighty-percent of the remaining 124 patients were diagnosed by a dermatologist during the study period. Females predominated in our patient series and the mean age of PMLE onset was 37.8 years. Lesions were commonly described as papular, edematous papulare, papulo-vesicular, eczematous, and plaque-like. Few skin biopsies were performed, and no patient had phototesting or photopatch testing. Topical corticosteroids and antihistamines were the most commonly prescribed therapies. Only four patients were treated with phototherapy. CONCLUSIONS: Patient demographics and lesion morphology in our cohort were similar to other reports, but patterns of diagnostic testing and treatment were somewhat different than those observed in photodermatology clinics.