Survivors of the Ebola outbreak in 2014 report a wide range of lingering symptoms that include fatigue and muscle pain, as well as neurological issues. But not much has been known about the persistence and severity of the symptoms over time.
Investigators from the Institute for Global Health & Infectious Diseases, David Wohl, MD, professor of medicine in infectious diseases, and William Fischer, MD, associate professor in pulmonary diseases, led an NIH funded study looking at Post-Ebola symptoms seven years after infection. Published in Clinical Infectious Diseases, researchers found that even five years after acute infection, a majority of people continued to have symptoms that greatly impacted their lives. The findings call for an understanding of the mechanism of post-EVD syndrome, along with therapeutic interventions, to help the thousands of EVD survivors. What researchers learn from survivors of Ebola may also help explain Long COVID.
From June 2015 to June 2016, researchers assessed 326 Ebola survivors in Liberia. They found that 75% of survivors, at about a year after they had Ebola, reported having at least one major symptom that started after they became sick, and persisted, while the vast majority reported symptoms that were highly interfering with their lives.
“When we followed these same people for over 6 years, we found that the odds of having these symptoms declined over time but still around half had Long Ebola symptoms,” said Wohl. “Interestingly, numbness of the hands and feet did not decline significantly over time in those who reported these symptoms initially.”
Like SARS-CoV-2, Ebola is an RNA virus. Wohl believes there may be a characteristic of RNA viruses that leads some people to experience lingering symptoms.
“We previously looked for evidence of inflammation in these Ebola survivors but found no difference in their levels of inflammatory markers and the levels in survivors without symptoms or in household members who never had Ebola. Some think that people with Ebola and COVID-19 harbor the virus, and that it can periodically emerge and trigger immune responses that contribute to symptoms, but so far there has not been strong evidence of this. It is not clear how these intermittent episodes of viral exposure would contribute to persistent symptoms.”
“Like many who have experienced Long COVID, many of those who had Ebola continue to struggle with health problems that rob them of quality of life. We need to learn more about these post-viral phenomena including their causes so we can identify appropriate treatments. What we learn from these survivors of Ebola may help us also better understand Long COVID.”
The study can be accessed here.