The guidelines have been modified for fieldwork in areas of undefined risk. The guidelines will be reissued as additional information about fieldwork practices and about the epidemiology of Hantavirus becomes available. Rodents are the known reservoirs of Hantaviruses, and other small mammals can be infected as well. Although current evidence indicates that the rodents harboring Hantavirus are most prevalent in rural settings, suburban or urban areas cannot be excluded as potentially affected.
Infection is believed to result from inhalation, inoculation through broken skin, or rodent bites.
Persons have been infected after only a few minutes' exposure to laboratory rodents infected with a similar virus. At present, there is no effective vaccine to prevent infection, and diagnosis and treatment are difficult. Enhanced precautions are warranted to protect against possible infection. It is the responsibility of each individual to take appropriate protective measures. It is the responsibility of the supervisor to ensure training and access to appropriate protective measures.