HHS Leads U.S. Government’s Response to Outbreak of Rift Valley Fever in the Republic of Kenya

Victor Omballa, a laboratory scientist in HHS/CDC’s Global Disease Detection Program, at work in the field laboratory in Garissa, Kenya.

March 6, 2007 – The Centers for Disease Control and Prevention (CDC) within the U.S. Department of Health and Human Services (HHS) is leading the U.S. government’s response to an outbreak of Rift Valley Fever in Northeastern Kenya. As of February 13, 2007, the Kenyan Ministry of Health had reported 560 probable cases and 146 deaths related to the outbreak.

Rift Valley Fever (RVF) is an acute viral disease that causes fever and, more rarely, several serious complications, including hemorrhagic fever, encephalitis, and blindness.  It is generally found in regions of Eastern and Southern Africa. While it primarily affects livestock, such as sheep and cattle, humans bitten by infected mosquitoes or other insects, or who are exposed to the blood, body fluids or tissues of infected animals, are also susceptible to the disease. The United States has never experienced an outbreak of Rift Valley Fever, but the virus -- like the West Nile virus -- could eventually reach this country. Introduction of the RVF virus into the United States would be a threat to both animal and human public health. 

HHS/CDC has deployed staff members to work in the affected areas. Also assisting in the investigation are trainees and graduates of the Field Epidemiology and Laboratory Training Program in Kenya, and representatives of the Kenya Medical Research Institute. 

HHS/CDC veterinarians and laboratories have assisted Kenya’s Ministry of Livestock and Fisheries Development with the enhancement of its disease-surveillance and -response strategies, and with the revision of standard case definitions for identifying suspect infected herds. HHS/CDC laboratory scientists are assisting with training and capacity-building in Kenyan veterinary labs, including through technology transfer, and an HHS/CDC Information Technology (IT) team based in Kenya is working with the Department of Veterinary Services in the Ministry of Livestock to improve data-management systems. An HHS/CDC team member has also accompanied both vaccination and veterinary-surveillance teams to the affected provinces, where they are collaborating with the Kenyan government on a risk-factor study to learn more about what causes severe Rift Valley Fever disease in humans.

The U.S. government team, which also includes representatives from the U.S. Army Medical Research Unit in Kenya and the U.S. Naval Medical Research Unit-3 in Cairo, Egypt, both part of the U.S. Department of Defense (DOD); and the Animal and Plant Health Inspection Service within the U.S. Department of Agriculture, are assisting a World Health Organization (WHO)/Global Outbreak Alert and Response Network (GOARN) team with medical, veterinary, and laboratory staff, and with laboratory equipment and reagents.  

At the request of the government of Kenya, the U.S. government also dispatched 150 doses of an experimental human vaccine, developed by the U.S. Army Medical Research Institute for Infectious Diseases (USAMRID) within DOD, to immunize staff involved in the surveillance of, and basic research on, Rift Valley Fever.

Last revised: October 11, 2007