Ebola virus disease is an incredibly serious and often deadly disease. While its fatality rate varies depending on the strain of the virus, Ebola-Zaire (the strain responsible for most human deaths) has a fatality rate of 90%.
Over the past several decades, there have been numerous outbreaks of Ebola, predominantly in tropical regions of Sub-Saharan Africa. These outbreaks not only lead to huge, tragic losses of human life but also have severe socio-economic impacts on those countries. Indeed, the worst Ebola epidemic in history between 2013-2016 resulted in not only over 11,000 deaths, but also led to drastic economic collapse in the region, with the three worst-hit countries experiencing a staggering 12% loss in GDP. Countries such as Liberia saw a decrease of trade, foreign investment and tourism due to increased safety concerns and flight cancellations. In addition, 30% of restaurants closed in Liberia and hotels in Nigeria saw a 75% reductions in revenue, contributing to mass unemployment. As a result, some experts say that the socio-economic effects of an epidemic such as this can result in more death than the disease itself.
Ebola is considered a zoonosis. This means that the virus originates in animals, such as gorillas and fruit bats, and only then spreads to humans. While we don't know how the virus spreads from animals to humans, we do know that is easily transmissible between humans by contact with the skin or bodily fluids of an infected person. This often takes the form of close contact with a person who has died of Ebola or using syringes and needles contaminated by Ebola patients. As such, sadly, relatives of an infected person often succumb to the disease.
The Ebola virus works by targeting the immune system, first by attacking dendritic cells. These cells are often referred to as the messengers between the specific and non-specific immune system, so by targeting them, the Ebola virus stops T lymphocyte cells being activated. As such, the virus replicates quickly, without being destroyed. The virus then spreads in the blood, causing immune cells called macrophages to release proteins into the bloodstream. This in turn triggers coagulation (blood clots), reducing blood supply to organs and resulting in multiple organ failure and mass haemorrhaging. This, coupled with a drop in blood pressure, culminates in death.
One problem with detecting Ebola is that symptoms take a long time to manifest, with most people showing symptoms between 8-10 days after infection and some people showing symptoms as late as 21 days after exposure. Furthermore, early symptoms such as a fever, headaches, joint and muscle aches and diarrhoea can also be difficult to distinguish from other illnesses such as influenza. This likely helped exacerbate the spread of Ebola in rural areas in sub-Saharan Africa as, without specialist equipment, it can be incredibly hard to diagnose until it is too late.
The easiest way to explain the problems with stopping the spread of Ebola is by using the example of the epidemic in Western Africa between 2013-2016. It began with a single boy, named Emile, being infected with the disease. Unfortunately, the disease then spread to his sister, mother, grandmother and a family friend, all of whom had tried to treat Emile before he died.
As they exhibited symptoms similar to common diseases in the area like malaria, typhoid fever or cholera, containment protocols were not deemed necessary. As such, by the time MSF had heard of this tragedy and flown a sample to Paris via Conakry to be tested, the virus had already spread to many other people. Nevertheless, while it took some time for MSF and other organisations such as the World Health Organisation to respond, their response was critical to limiting the spread of the Ebola virus and helping to save many people. Despite some disputes between MSF and WHO about the best way to treat the patients, they were able to work with the government of Guinea to put an alert system in place across the country. This meant that any patients who were suspected of being infected with Ebola could be quickly isolated and treated, increasing survivability and reducing the virus's spread. Indeed, after a few months, there were no more reported cases of the Ebola virus.
Nevertheless, the system was not perfect. The reason that there were no more reported cases was actually because villagers had grown suspicious of the foreign medical staff and therefore not reported cases to the authorities. Further, even after death, the virus can spread. While the best way to dispose of the bodies would have been by cremation, there were several religious and cultural objections, reducing the effectiveness of the containment of the Ebola virus.
To date, no treatment has been proved to cure Ebola. Nevertheless, humanitarian organisations like Médecins Sans Frontières (Doctors without Borders) have taken steps to significantly improve survival rates. For example, fluids and electrolytes can be provided intravenously to replace those which are lost. Oxygen can also be provided to ensure that saturation levels in the blood remain high, thus allowing the body to fight the virus itself. In addition, when an Ebola epidemic is declared, steps are also taken to reduce the chances that healthcare workers get infected - after all, they have the highest risk of infection from the patient. Following an outbreak, Ebola suits are flown in to protect workers from contamination. Patients are also quarantined in special hospital wards to reduce the spread of the disease. Moreover, while there is currently no antiviral drug that is licensed to treat Ebola, there are multiple drugs being developed. Techniques such as blood transfusions from survivors and mechanically filtering the blood are also being trialed.
One must also realise that the effects of Ebola on a person's health can be incredibly long-term, with many survivors reporting other adverse symptoms after recovering. One of the most prevalent secondary symptoms is eye damage, with a Sierra Leone physician reporting that many surviving patients went blind. This can have incredibly serious consequences for the infected people, especially in Western Africa, as a lack of experienced ophthalmologists (eye doctors) means that these conditions can't be treated effectively.
Since an emergency was declared on 1st August 2018, the DRC has been fighting the world's second-largest Ebola epidemic on record, with more than 2100 lives lost so far and 3243 confirmed cases. While the outbreak is mostly contained to the North Kivu, South Kivu and Ituri provinces, there is still a huge risk of the disease spreading. As such, the World Health Organisation have over 650 staff on the ground supporting the Congolese government and neighbouring countries have already taken steps to reduce the risk of the virus spreading.
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