Ebola: Lessons from the Latest Pandemic

The 2014 re-emergence of Ebola virus disease (EVD) quickly became the largest and deadliest outbreak of the disease ever recorded. Originating in Guinea, it spread to neighboring countries and others around the globe. As potentially the firstline health care contacts during a pandemic, all primary care providers need to be aware of the signs and symptoms of EVD so that they can quickly identify, isolate, and treat affected patients. This article describes the history, pathophysiology, diagnosis, and treatment of the disease.

In 1918, influenza virus—in the most deadly pandemic in the past century—killed an estimated 20 to 50 million people worldwide.¹ A more recent example of a devastating pandemic that is still sweeping the globe with high morbidity and mortality is HIV/AIDS. According to the World Health Organization (WHO), in 2013, 35 million people were living with HIV/AIDS worldwide and 1.5 million people died from HIV/AIDS–related illnesses.² Similarly, emerging respiratory infectious diseases such as avian influenza, Middle East respiratory syndrome (MERS), severe acute respiratory syndrome (SARS), and H7N9 influenza have all been named as possible threats due to their high fatality rates.³

In 1999, the WHO created a preparedness plan for pandemic influenza (updated in 2005) to provide information on reducing the risk for infection and informing government and health care organizations of proper outbreak response.3 The virulence and high mortality associated with Ebola virus disease (EVD) necessitate a similarly detailed preparedness plan, including international collaboration and commitment to providing research, training, support, and personnel to combat the current outbreak and prevent future outbreaks (see “‘Present’: Ebola's Impact on PAs in Liberia” for an interview with the President of the Liberia National Physician Assistants Association).

All primary care providers (PCPs) need to be aware of the signs and symptoms of EVD so that they can properly identify suspected cases, take necessary precautions to avoid transmission, and quickly transfer patients to facilities equipped to provide isolation and appropriate supportive treatment. PCPs may be the first providers to come into contact with patients infected with a pathogen during a pandemic, especially if the initial symptoms are mild enough not to warrant a visit to the emergency department. In 2003, the first case of SARS was diagnosed and treated by a Canadian family physician, and the initial case of H1N1 in Japan during the 2009 pandemic was first seen by a family physician as well.³

If PCPs are not sufficiently prepared to deal with a patient exhibiting signs or symptoms of EVD, it is likely that they, their staff, and other patients will be at greater risk for contraction and transmission. It has been found that PCPs are less likely to be prepared for dealing with pandemics, especially since high-level personal protective equipment (PPE)—eg, N95 masks, gowns, eye protection—are stocked at a lower rate in outpatient clinics than in hospitals.³ PCPs should prepare by familiarizing themselves with the signs and symptoms of EVD and by stocking high-level PPE.

In March 2014, the WHO received reports of a developing epidemic of EVD in Guinea in West Africa. The outbreak started in two districts of that country during December 2013; from there, it spread to Liberia and Sierra Leone, with scattered cases in Nigeria, Mali, Senegal, Spain, the United Kingdom, and the United States, making it the largest EVD epidemic ever recorded. The outbreak’s morbidity and mortality surpass that of all previous EVD epidemics in the past 38 years combined.⁴ As of August 19, 2015, there have been 15,188 laboratory-confirmed cases (the total number of cases is estimated at 28,000) and 11,286 deaths in the current epidemic.⁵

The first recorded outbreak of EVD occurred in 1976 in a village called Yambuku, located near the Ebola River in Zaire (now known as the Democratic Republic of Congo). At that time, a team of scientists from the CDC was sent to Zaire to identify the agent responsible for a deadly hemorrhagic fever that was ravaging the local hospital.⁶ This and subsequent outbreaks in central Africa were contained due to rapid coordinated efforts to stop the spread of the disease through a number of strategies.

Among these strategies, quick diagnosis, isolation of contacts, and quarantine of the greater area played a significant role in stemming the outbreak.⁴ Additional steps that helped curb disease spread included rapid burials with disinfectants and home visits by health workers, with patient education provided to help to assuage any fear villagers may have had of foreign health workers.6 Finally, health workers and surveillance teams were provided with PPE and were encouraged to continue their work despite the outbreak, with the promise that they would receive treatment equal to that given to foreign aid workers if they too fell ill.⁶ Each of these measures utilized in tandem allowed for control of the initial outbreak.

Despite being similar to previous outbreaks in terms of transmission rate, incubation period, fatality rate, and estimated basic reproduction number (R0, the estimated number of people infected by a single patient), the number of persons affected by the current epidemic eclipses any previous outbreak. Thus, political, economic, and social issues, rather than biologic characteristics, have made this epidemic the largest in history.⁴ The lack of medical infrastructure in the most severely affected nations has hindered efforts to provide care to those infected, and the number of patients requiring medical treatment vastly exceeds the number of hospital beds available.⁴

The WHO estimates that cutting transmission rates by 50% through the rapid and rigorous employment of sophisticated infection-control practices will halt the growth of the epidemic and eventually eradicate the virus from the human population.4 There is, however, the danger that if control measures are not implemented soon, EVD will become endemic in West Africa.4 In the US, early recognition, a well-­informed public, and advanced medical infrastructure will allow for quick identification and containment of the virus. Public awareness, especially among health workers, is essential to stopping the epidemic’s spread. 

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