Editor's Note: The Ebola outbreak in western Africa is the largest in history. Two US healthcare providers working with agencies in Africa are infected and are being treated. Two other Americans, both Peace Corps volunteers in Liberia, were reportedly exposed and are being monitored in isolation, although they remain symptom-free. Peace Corps has recently announced that it will be pulling its volunteers out of the most affected countries of Sierra Leone, Liberia, and Guinea. Although it has emphasized that the risk for transmission to the United States is low, the US Centers for Disease Control and Prevention (CDC) has also stated clearly that healthcare professionals should query patients with symptoms consistent with Ebola presentation about recent travel to affected parts of Africa. Medscape spoke with the CDC about key messages for US healthcare professionals.
Medscape: Can you review the epidemiology of the current outbreak?
CDC: Ebola is a severe, often fatal, viral hemorrhagic fever. The first Ebola virus was detected in 1976 in what is now the Democratic Republic of Congo. Since then, outbreaks have appeared sporadically. The current outbreak is the biggest and most complex Ebola outbreak ever documented.
Ebola has an abrupt onset of symptoms similar to many other illnesses, including fever, chills, weakness, and body aches. Such gastrointestinal symptoms as vomiting and diarrhea are common, and in approximately 45% of cases there is hemorrhaging (serious internal and external bleeding).
The current outbreak in West Africa is centered in the countries of Sierra Leone, Guinea, and Liberia. At least 2 cases have been reported in Nigeria.
As of August 6, 2014, there have been more than 1700 confirmed and suspected Ebola cases in these 4 countries and 932 suspected case deaths. Up-to-date statistics may be found here.
Medscape: CDC has emphasized that this is not an easily transmissible infection but requires contact with bodily fluids from an infected individual. That places healthcare professionals working with these patients at risk. Can you discuss transmission? What is the period of infectivity?
CDC: In most Ebola outbreaks, healthcare workers are at risk for infection when strict personal safety precautions or sharps management procedures are not followed. Ebola is transmitted through direct contact with body fluids from infected patients (including but not limited to blood, sweat, feces, urine, vomitus, and semen), and so avoiding contact with these materials is important. Protective measures known as standard, contact, and droplet precautions are considered sufficient protection against transmission; these include gloves, gowns, facemask, and eye protection (mask, face shield) for personnel providing routine care. In general, symptomatic patients are infectious and can transmit Ebola virus, so the period of infectivity is related to the duration of symptoms and will vary from patient to patient.
CDC has issued updated interim guidance for healthcare workers providing care to suspected Ebola patients in the United States.
Medscape: The key question for healthcare professionals in the United States is, how likely is transmission to occur here?
CDC: The risk to the US general population of contracting Ebola virus infection is exceedingly low. There is a risk for Ebola to be introduced to the United States by an infected traveler from Africa. If that were to happen, widespread transmission in the United States is highly unlikely owing to our systematic use of strict and standard infection control precautions in healthcare settings, although a cluster of cases is possible if patients are not quickly isolated. Community spread is unlikely because of differences in cultural practices, including how community and family members handle their dead.
CDC advises against nonessential travel to Guinea, Liberia, and Sierra Leone, and to take extra precautions if travelling to Nigeria, because such travel represents the primary risk for exposures to Americans. Two infected American healthcare workers serving as volunteers in Liberia have been brought to the United States for treatment, but there is no risk for Ebola virus within the community or hospital setting, because these patients are being managed in strict isolation.