A feared hallmark of Ebola – uncontrolled bleeding – is a rare symptom in the current outbreak, according to an article in this week’s New England Journal of Medicine that is the largest clinical analysis to date of the West African epidemic.
The study, authored by a team from Tulane University and the Viral Hemorrhagic Fever Consortium, followed the first 106 Ebola patients admitted to the Kenema Government Hospital in Sierra Leone at the beginning of the outbreak in May and June.
The team was able to get an unprecedented amount of detailed laboratory data on the emerging epidemic because researchers have been stationed at the hospital for the last decade studying Lassa virus, another hemorrhagic fever endemic to West Africa. Limited clinical and lab data exists for Ebola outbreaks as prior cases sporadically occurred in remote regions with few resources.
“This is the largest and most detailed case series of Ebola patients so far,” said lead author Dr. John Schieffelin, assistant professor of clinical medicine and pediatrics at Tulane University School of Medicine.
Of the 87 patients tracked with known outcomes, 74 percent died. Researchers estimated the average incubation period for the current outbreak to be six to 12 days. The most common symptoms and rates of prevalence were fever (89 percent), headache (80 percent) weakness (66 percent), dizziness (60 percent), diarrhea (51 percent), abdominal pain (40 percent), and vomiting (34 percent). Only one patient experienced bleeding.
Several factors increased the risk of death, including age, viral load and certain symptoms like weakness and diarrhea. Roughly 94 percent of cases with diarrhea were fatal. Patients 45 and older had a 94 percent fatality rate, while the death rate for those under 21 was 57 percent. Cases admitted with higher viral loads were also more likely fatal.
Schieffelin said that treatments must focus on managing fluid and electrolyte losses so patients can survive long enough to suppress the virus.
The full article is available on the New England Journal of Medicine website.