Academic journal article Journal of Environmental Health

2014 Ebola Outbreak: Implications for Environmental Health Practice

Academic journal article Journal of Environmental Health

2014 Ebola Outbreak: Implications for Environmental Health Practice

Article excerpt


Ebola. The word is enough to cause worldwide fear and ignite heated political debate in the U.S. Public health has historical roots in examining the etiology and risk factors associated with the environment, both biological and chemical. Early historical examples of environmental health practices to combat infectious disease include malaria and cholera. Environmental health practitioners address issues of risk and exposure in their routine work and therefore are uniquely positioned to offer insights about response to the recent Ebola outbreak. The goal of this article is to highlight the role of environmental health practitioners in dealing with emerging infectious diseases such as Ebola and highlighting available resources.

Etiology and Natural History of Ebola

Ebola virus disease (EVD) is a hemorrhagic fever in the viral family Filoviridae, genus Ebolavirus. Of five known species, three have been associated with large outbreaks among humans. Ebola is transmitted among mammals through contact with bodily secretions and fluids including blood, breast milk, feces, saliva, semen, sweat, urine, and vomit (Centers for Disease Control and Prevention [CDC], 2014a). Fruit bats are thought to be the natural host for the virus, and other animals that have been associated with the virus include chimpanzees, gorillas, monkeys, antelope, and porcupines (World Health Organization [WHO], 2015a).

The virus can be introduced to humans in the same manner through contact with an infected animal's bodily fluids or secretions. Cases have been associated with butchering and eating bush meat (CDC, 2014a). Transmission occurs through broken skin or mucous membranes (CDC, 2014a). Human-to-human transmission occurs through direct contact with bodily fluids and secretions or through indirect contact with contaminated surfaces (e.g., bedding, clothing, needles, or medical equipment). No known cases exist of air- or waterborne transmission (CDC, 2014a). People can continue to transmit the virus as long as it is present in their system, even after symptoms have disappeared. The World Health Organization (WHO, 2015a) reports that men can continue to transmit the virus through semen up to seven weeks after recovery from illness, and the Centers for Disease Control and Prevention (CDC, 2014a) report that the virus has been found in semen for up to three months, although it is unclear whether the virus is spread through postrecovery sex.

In humans, exposure to Ebolavirus leads to EVD, a severe, acute infection, with an incubation period (time from infection to onset of symptoms) ranging from 2 to 21 days. Humans are not contagious until they develop symptoms, which include sudden onset of fever and fatigue, muscle pain, headache, sore throat, vomiting, and diarrhea. EVD can also cause kidney and liver impairment as well as internal and external bleeding. Because the initial symptoms are similar to other illnesses, EVD can be difficult to diagnose and is confirmed through laboratory tests (WHO, 2015b).

No vaccine for EVD is currently approved for use in humans although clinical trials are proceeding on an expedited schedule (WHO, 2015b). No proven treatment exists, either, although several potential treatments are currently being evaluated, including drug therapies, immune therapies, and blood products. Hydration (oral and intravenous) and other supportive symptom-specific care can improve survival (WHO, 2015b).

Epidemiological Perspective

EVD is a relatively new disease to humans, with the first cases reported in 1976 in rural areas of Central Africa, simultaneously appearing in Sudan and Democratic Republic of the Congo (DRC) (Medecins Sans Frontieres [MSF], 2015; WHO, 2015a). The case-fatality rate ranges from 25% to 90%, depending on the viral strain (MSF, 2015; WHO, 2015a). The 2014 West Africa outbreak of the Zaire strain began in Guinea in March, and had widespread transmission in Guinea, Liberia, and Sierra Leone. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed


An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.