Epidemiology of Ebola (subtype Reston) virus in the Philippines, 1996

Ebola (subtype Reston [EBO-R]) virus infection was detected in macaques imp orted into the United States from the Philippines in March 1996. Studies we re initiated in the Philippines to identify the source of the virus among m onkey-breeding and export facilities, to establish surveillance and testing , and to assess the risk and significance of EBO-R infections in humans who work in these facilities. Over a 5-month period, acutely infected animals were found at only one facility, as determined using Ebola antigen detectio n. Three of 1732 monkeys and 1 of 246 animal handlers tested had detectable antibodies; all were from the same facility, which was the source of infec ted monkeys imported to the United States. Virus transmission, which was fa cilitated by poor infection-control practices, continued for several months in one facility and was stopped only when the facility was depopulated. No ne of the 246 employees of the facilities or 4 contacts of previously antib ody-positive individuals reported an Ebola-like illness. This investigation suggests that human EBO-R infection is rare.