There is no direct evidence of aerosol spread of the virus outside a laboratory setting. This means that these strains are all closely related and are the same virus species. Viruses usually have differences in their genetic material when various strains are compared. Thus, the changes found are not of any particular importance and are not unexpected. The reservoir and natural history of filoviruses remain unknown.
Nonhuman primates are even more sensitive to infections with filoviruses than humans are.
It seems likely that these animals serve as indicators of filovirus activity, but there is no evidence linking them to the maintenance cycle of the virus. At the request of the Texas Department of Health, CDC has sent medical scientists to Texas to assist state and local health officials in the investigation. The CDC investigators are working with the Texas Department of Health and the owners of the quarantine facility to help prevent additional cases, collect specimens for diagnostic testing, study the clinical course of the diseasein the ill primates, and offer advice to the facility staff about how to limit the spread of the disease. CDC is working with the Philippine Ministry of Health and the World Health Organization as attempts are made to gather information concerning the source of the virus. No vaccine exists to protect against filovirus infection, and no specific treatment is available for disease caused by these viruses.