Arenavirus
Three fatal illnesses occurring between May 1999 and June 2000 have been attributed to infection with Whitewater Arroyo (WWA) virus, which is an arenavirus initially identified in New Mexico woodrats. The patients were females aged 14, 30 and 52, and all resided in different counties in California. Symptoms at hospitalization included fever, headache, and myalgias. Each soon developed lymphopenia, with thrombocytopenia present in two of the women. All three developed acute respiratory distress syndrome while two developed liver failure with secondary hemorrhage. All died within 1 to 8 weeks after the onset of illness. Although WWA virus is known to reside in rodents in rural California, investigation is ongoing to determine how these women were infected. WWA has not previously been known to cause disease in humans.
Other arenaviruses are associated with hemorrhagic fevers such as Lassa in West Africa, and Machupo in South America. Lymphocytic choriomeningitis virus is also an arenavirus that causes human infections in North America. Because rodents are the reservoir for arenaviruses, the Centers for Disease Control (CDC) has suggested guidelines for prevention of infection that include avoidance and control (MMWR 49:709,2000).
