Africa has been fighting a deadly illness for decades, while the rest of the world is fighting against influenza, heart attacks, and burnout. Ebola disease, or Ebola hemorrhagic virus (EVD), is a rare but deadly disease that occurs mainly on the African continent.
Ebola virus disease outbreaks
In 1976, two outbreaks of Ebola virus occurred simultaneously. First, the disease was found in South Sudan’s Nzara. Next, the Ebola disease spread to Zaire and Yambuko in the Democratic Republic of Congo, near the Ebola river that gave the virus its name. In 1976, there were 318 Ebola cases and 280 fatalities in an outbreak lasting 11 weeks. The outbreak had a high death rate of 88% but was contained quickly.
According to Dr. Joel Breman’s report and that of his colleagues, in 1976, the key for diagnosis was the relative quick recognition by the authorities of a potentially new, severe disease. The report also identified the first Ebola case, an adult male who was hospitalized August 1976. The blood of a midwife nun who was infected in the same hospital a month after the first Ebola case was hospitalized was sent to Belgium to be tested. The entire area was then quarantined.
West Africa has experienced the most deadly Ebola outbreak in almost 40 years. The first case of Ebola was reported in December 2013. In Guinea, a small village reported that a baby boy aged 18 months was infected with bats. Ebola spread quickly throughout Guinea. The disease spread quickly due to a lack of public health infrastructure, and weak surveillance. The disease spread quickly to Guinea’s neighboring countries of Liberia, Sierra Leone and Guinea. It was the first time that the Ebola virus reached densely populated cities, which allowed the disease to spread quickly.
Total reported Ebola cases in Guinea and Sierra Leone were 28, 616 with 11,310 deaths. In addition, there were 36 cases and 15 deaths outside of the three countries. The outbreak claimed the lives of many healthcare workers. Liberia suffered a loss of 8% of doctors, nurses and other healthcare professionals during the outbreak. The World Health Organization (WHO), on March 29, 2016, lifted the Public Health Emergency of International Concern status (PHEIC), referring to the Ebola virus outbreak in West Africa.
Ebola virus and its transmission
Ebola virus is a deadly illness that affects mainly humans and nonhuman primates, such as gorillas, monkeys and chimpanzees. The disease is caused by an Ebolavirus group of viruses.
Ebola virus is composed of single-stranded filamentous RNA. Ebolavirus is composed of six different species,namely Ebola virus, Sudan virus, Tai Forest virus, Bundibugyovirus, Reston and Bombalivirus. Only four of these (Ebola and Sudan) are infectious to humans. They are all recognized as being from Africa. Reston virus first appeared in 1989, when monkeys infected with the virus were imported from Mindanao in the Philippines to Reston, Virginia. Reston virus has been observed to cause illness in nonhuman primates, pigs and dogs but not in humans. Bombali virus was recently found in bats. It is unknown if this virus can cause human disease.
Ebola is a zoonotic illness – it involves transmission from animal to human. Scientists suspect that fruit bats are the most likely candidate species to be Ebola’s natural reservoir. Fruit bats may be naturally infected with Ebola, but scientists have yet to isolate the virus from these bats.
The virus is spread from human to human by wild animals. Direct contact with body fluids from a symptomatic person, such as urine, blood, feces and vomit, or sweet, is the main mode of transmission. The virus could be transmitted through skin breaks or inoculations into the nose, mouth or eye. Although no human-to-human transmission has been reported, the Ebola virus is present in saliva.
In general, the Ebola virus transmits most easily during the acute phase of infection. When caring for patients with symptoms, healthcare workers who do not have the appropriate protection can easily become infected.
Treatments and prevention of symptoms
Infection can cause symptoms to appear 2-21 days after the initial infection. Flu-like symptoms include fever, nausea, vomiting, fatigue, and headache. In the severe stages, patients will experience bleeding due to small infections, hemorrhagic disease, and eventually multiple organ failure. Blood pressure is often decreased due to severe bleeding or loss of fluids. Average EVD fatality rates are around 50%. Some outbreaks have resulted in mortality rates of up to 90%.
The FDA in the United States approved Ervebo as the first vaccine to prevent Ebola virus infection caused by Ebola viruses. Currently, there is no antiviral approved drug for treating EVD. In the West Africa outbreak, four experimental treatments were used. Two of them showed a higher survival rate. Early treatment of symptoms can increase the chance of survival. Survival is improved by supportive care such as intravenous or oral rehydration.
The survivors may have long-term problems, such as a stroke, inflammation of the liver, muscle and joint pains, and weakness. Patients who have recovered from the virus cannot transmit it anymore, but they need to boost their immunity to avoid other consequences.
A lack of approved treatment makes prevention the best option to combat the disease. Other quarantine measures, such as contact precautions and case isolation, must also be observed. Wearing protective equipment when dealing with EVD cases is a must. Direct contact with the deceased should be avoided.
We can prevent the spread of zoonotic diseases like the Ebola virus by raising awareness about the transmission from wildlife to humans. It is important to control the consumption and contact of wildlife meats.
