Ebola in the US: Media over-exaggerated into a panic
Although Ebola has been a problem in African countries for years, it has since become an “epidemic” once an American doctor was diagnosed with the deadly disease. Since then, the United States has taken several precautions to prevent further spread of the disease to the country. The media has hyped up the situation and caused a panic in a significant portion of the United States population. Is this scare rational? Let’s take a look.
One method of prevention is screening for the virus at airports and ports for travelers arriving from African countries. As with any medical testing, there is the chance that a patient will test positive, even if they don’t have the disease. This is known as a false positive. As per government and Center for Disease Control instructions, anyone who tests positive for Ebola must be quarantined. This means that even if a patient tested false positive, they must spend time in quarantine.
The article goes into the mathematics of the chance that a patient actually has the disease if they test positive. The author uses the idea of conditional probability. The question is: what is the probability that a patient has Ebola given they test positive for Ebola? The table below outlines the problem nicely.
According to the given information, the probability that a patient doesn’t have Ebola is 60%. The article states that 50% of patients with Ebola die. Thus, the probability that someone “does not have Ebola or has the virus, but survives, is […] 80%.” So we see that the media has gone too far and caused an unnecessary and misinformed nationwide panic. There is a “75% chance that the positive Ebola test was wrong” and “nearly 97% odds of being Ebola-free.”
Source:
http://qz.com/282505/lets-do-some-math-on-ebola-before-we-start-quarantining-people/