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Long-term Adverse Health Effects of Ebola Survivors Examined in New Lancet ID Paper

April 22, 2015
Findings from a MHRP longterm study of survivors of the 2008 Uganda Ebola Outbreak were published in The Lancet Infectious Diseases today.

Survivors of the 2007-08 Bundibugyo ebolavirus (BDBV) outbreak in Uganda experienced negative health effects that persisted more than two years after the outbreak claimed 39 lives, according to findings from an MHRP study published in The Lancet Infectious Diseases today. 

The study represents the largest long-term study to-date on Ebola survivors, and examines health events more than two years after inital exposure to BDBV. 

In an accompanying Lancet commentary based on the paper, Dr. Daniel G Bausch, pandemic and epidemic disease specialist with the World Health Organization (WHO), noted that the study "provides valuable insights into the dynamics of the antibody response after Ebola virus infection." 

Results of Clark and colleagues’ study "highlight the sad fact that, even for the more fortunate who survived infection with the highly lethal Ebola virus, their ordeal is often still not over," he writes. Our collective public health and research response needs to carry on until it is."

MHRP's Dr. Hannah Kibuuka, with the Makerere University Walter Reed Project, served as the principal investigator on the study.

Researchers studied forty-nine probable and confirmed BDBV adult survivors and 157 of their seronegative contacts in this observational study that enrolled volunteers 29 months after the outbreak. Information on health status, functional limitations and demographics was collected, along with blood samples for analysis. 

Researchers found that survivors were at significantly increased risk of ocular deficits, blurred vision, hearing loss, and neurologic abnormalities such as difficulty swallowing and sleeping. Survivors also reported more chronic health problems and limitations due to memory loss or confusion.

Limitations in the ability to perform routine functions were more prevalent among BDBV survivors.  In addition, survivors were twice as likely to report having chronic health problems lasting more than a year. These included pain in the abdomen, back, and large joints, fatigue, impotence and severe headaches. Limitations due to memory problems or confusion were approximately six times more prevalent among BDBV survivors than uninfected participants of similar age and sex.

“The ongoing Ebola virus disease outbreak in West Africa has resulted in thousands of fatalities, but also thousands of survivors. The limited evidence from this study and the work of others indicates that strategies to address the long-term health needs of survivors are needed,” said COL Nelson Michael, director of MHRP at the Walter Reed Army Institute of Research.

Makerere University Walter Reed Project (MUWRP) of Kampala, Uganda conducted this long-term retrospective cohort study in collaboration with the Uganda Ministry of Health and the district health care workers in Bundibugyo. For more information, visit

MHRP Support for Ebola Research

For more than a century, the US military medical community has solved many significant international health problems, particularly in the area of infectious diseases. MHRP and its parent command, the Walter Reed Army Institute of Research (WRAIR), have been involved in the testing of Ebola vaccines since 2009.

MHRP’s site in Uganda, MUWRP, conducted the first Ebola Vaccine trial in Africa in 2009-12, using an early-generation DNA vaccine candidate developed at the VRC. The results were published online in the Dec. 2014 edition of The Lancet and those results, in addition to other studies, helped lead to a clinical evaluation of a more potent cAd3 vaccine.

MUWRP also began a new Phase Ib clinical trial of two experimental Ebola vaccines began in February 2015 They are conducting the study using Chimpanzee Adenovirus type 3 vector (ChAd3) vaccines, co-developed by the Vaccine Research Center (VRC), National Institutes of Allergy and Infectious Diseases (NIAID) and GlaxoSmithKline.

The MHRP Department of Laboratory Diagnostics and Monitoring (DLDM) provided crucial laboratory support for another novel Ebola vaccine that was tested at the WRAIR and at multiple sites in the US and Canada. Results from that study were published in the NEJM on April 1, 2015.

The Walter Reed Program-Nigeria, another MHRP site, will begin testing the Zaire strain ChAd3 Ebola vaccine in a larger Phase II study that will take place at 10 sites in four West Africa countries later this year. The virus causing the current West African outbreak is closely related to the Ebola Zaire strain.