An atypical Ebola outbreak makes history and misery

March 18th, 2015

The ongoing record outbreak of Ebola virus in West Africa is killing six out of every ten people infected. And that’s the good news.

“The mortality rate in some outbreaks can be as high as 90%, but in this outbreak it is currently around 60%, indicating that some of our early treatment efforts may be having an impact,” said Stephan Monroe, MD, deputy director the National Center for Emerging Zoonotic and Infectious Diseases at the Centers for Disease and Control.

Since the first report of Ebola infection in March, there have been more than 1,200 cases reported and 672 deaths in Guinea, Liberia and Sierra Leone. “This is the largest Ebola outbreak in history and the first in West Africa,” Monroe said at a July 28 CDC press conference. “It’s a rapidly changing situation and we expect there will be more cases in these countries in the coming weeks and months.”

A particularly troubling aspect of the outbreak is that health care workers have been infected despite wearing elaborate barrier precautions to treat Ebola patients. With only murky suggestions and rumors of needlesticks and other exposures, one is left with little more to conclude at this point than Ebola is a singularly unforgiving virus. Ebola does not spread through the air, requiring close encounters with infected patients or their body fluids. Spread through contaminated environmental surfaces and fomites may also be a factor in some of the cases.

“Two American health care workers at a hospital in Monrovia, Liberia, have been infected,” Monroe said. “One of the health care workers, a physician who worked with Ebola patients in the hospital, is symptomatic and in isolation. The other health care worker developed fever but no other signs of illness. The physician’s family had been living with him in Liberia. Thankfully, the family members had returned to the United States before the doctor got sick and therefore are not at risk for contracting Ebola or spreading it to anyone here. Out of an abundance of caution, the family is currently on a 21-day fever watch. I want to emphasize that Ebola isn't contagious until symptoms appear.”

Another unusual expression of the outbreak is that the Ebola strain has continued to transmit and spread regionally. Indeed, the image of a typical Ebola outbreak -- short violent bursts of transmission followed by a rapid cessation of cases – has led to the common observation that the deadly pathogen is something of an underachiever in the viral world, killing its victims too quickly to sustain itself. Not so with this outbreak, which has seen cases flung wider as those incubating the virus take it to other regions.

“This past Friday, the Nigerian Ministry of Health confirmed that a man in the country’s capital, Lagos, died from Ebola infection,” Monroe said. “The man had been in isolation in the hospital since arriving at the Lagos airport from Liberia, where he apparently contracted the infection. Health authorities are currently investigating whether passengers or crew on the plane or other people who had contact with the ill traveler are at risk for infection.”

While emphasizing that Ebola poses little risk of emerging in the U.S., Monroe said the CDC is recommending the following for all health care providers:

• Take good travel histories of patients to identify any who have traveled to West Africa within the last three weeks.
• Know the symptoms of Ebola -- fever, headache, joint and muscle aches, weakness, diarrhea, vomiting, stomach pain and lack of appetite and, in some cases, bleeding.
• Know what to do if you have a patient who has Ebola symptoms. First, properly isolate the patient. Then, follow infection control precautions to prevent transmission. Most importantly, avoid contact with blood and body fluids of infected people.