The medical world can be a confusing place. Patients and their families might feel overwhelmed by the large vocabularies and complicated explanations they get from their health care providers. Students entering health care also struggle to grasp the complexity of health sciences, and are forced to memorize huge amounts of information. We hope to make understanding the medical world a bit easier. Look around! These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay seeking it because of something you have read or seen in any video.
Ebola disease is a life-threatening illness caused by the Ebola virus. In December 2013, a 2-year-old toddler died in a rural village in Guinea, sparking the largest Ebola outbreak the world has ever known (Baize et al., 2014). The outbreak primarily involves three countries in Western Africa: Guinea, Liberia, and Sierra Leone (although there have been additional cases/deaths in other countries). As of early November 2014, there have been over 13,000 cases and almost 5,000 deaths, although experts believe that these numbers could be 250% greater as many patients never seek medical assistance. This outbreak is larger than all previous Ebola outbreaks combined, and the Center for Disease Control (CDC) predicts the disease could spread to other West African countries, infecting over 1 million people by January 2015 (Meltzer et al., 2014)!
The Ebola outbreak is serious because:
Many viruses follow the same sequence of events to replicate themselves. In regards to the Ebola virus:
It takes between 2 to 21 days (most commonly: 8-10 days) for the Ebola virus to replicate enough to cause symptoms, and initially Ebola can look like a case of a bad flu. To help make things clear, the CDC has listed two key criteria that a patient must meet to raise suspicion of Ebola:
Ebola can cause many other symptoms including weakness, poor appetite, rash, red eyes, hiccups, cough, chest pain, and difficulty breathing/swallowing. On their own, these symptoms do not indicate that a person has Ebola, since they could be caused by a number of things.
If health care professionals suspect Ebola, they’ll order the following blood tests to confirm the diagnosis:
Ebola is spread when the bodily fluids of a sick patient get inside of a healthy person. These bodily fluids include blood, vomit, feces, urine, saliva, sweat, breast milk, and semen. The virus can survive in bodily fluids that come in contact with surfaces like floors, walls, and handrails for about 24 hours although the chance of infection after a few hours drops significantly (Center for Disease Control, 2014c). Family, friends, and healthcare professionals all care for patients and are at higher risk of coming into contact with the virus. These folks and anyone else at risk (e.g. funeral directors and lab workers) should protect themselves with personal protective equipment, and remove it in the correct order: gloves, then face shield, then gown, and finally mask!
Ebola can also spread through contact with body fluids of infected bats and primates, placing individuals who work with or in close proximity to these animals at a higher risk of contracting the disease.
Once a patient recovers and is symptom-free, he or she is no longer able to transmit the virus. The one exception is transmission through semen, which can transmit Ebola for up to 3 months after infection. Ebola patients are encouraged to abstain from sex during this time. Ebola survivors can go on to have a normal life and are immune to the virus for up to 10 years.
To be clear, Ebola does not spread through the air, through water, or through food, so you can breathe, drink, and eat without worry!
It’s really useful to know how many people are likely to get infected from a single contagious patient (assuming that nobody gets vaccinated). A number called R₀ (pronounced: R-“not”) allows scientists to rank how contagious a disease is:
In some diseases, a single patient can spread the disease for days (e.g. Ebola) and in others, for decades (e.g. HIV). It turns out that Ebola has an R₀ of 2, which means that a single patient will transmit the virus to an average of 2 other people (unless we intervene). Compare this with one of the most contagious viruses around - Measles, which can travel in the air and spread to an average of 18 people!
Unfortunately there is no direct treatment for Ebola (no vaccines or medications) yet. Instead, health care workers provide supportive care, which focuses on keeping the patient alive during the illness while his/her body fights the disease. Supportive care includes:
Typically people who are likely to survive begin to recover between 6 and 11 days after symptoms initially began. Older patients and those that have more serious symptoms such as bleeding early on in the course of the disease typically die within 6 to 16 days after symptoms initially began (Center for Disease Control, 2014b).
Why are some countries more affected by Ebola than others? The answer comes down to having an effective public health system. There is a race taking place. On one side, the virus is quickly moving from one person to another. On the other side, the public health team is trying to find and isolate everyone with Ebola so that the virus can’t spread. Speed matters on both sides, and if the public health team can move quicker than the virus, then transmission ends. This requires good surveillance and contact tracing.