The statistics on the coronavirus have been confusing, potentially deliberately misleading and downright scary. So let’s take a look at the latest report by the World Health Organization and the Centers for Disease Control and Prevention to really understand what it means for your individual risk of infection -- in normal language.
There are two types of risk. The first is called case fatality rate. That is simply the number of deaths of those infected with coronavirus divided by the number of infected. In China, according to Thursday’s WHO situation report, there is a 3.5 percent case fatality rate meaning if you are infected in China, there is a 3.5 percent chance you will die. As for the rest of the world, the case fatality rate is currently about 1.5 percent.
However, this does not necessarily mean that the actual fatality rate of coronavirus is 3.5 percent. Here’s why. Very mild cases of the coronavirus in which the patient only exhibits low-grade fever, cough or even no symptoms at all, may not have been reported. This means that the number of infected cases could be a lot higher, making the actual fatality rate a lot lower. Statistical modeling out of the WHO is currently predicting the actual fatality rate at somewhere between 0.3 percent and 1.0 percent (much lower than the current fatality rate). This means if you are infected there is between a 0.3 percent and 1.0 percent chance you will die. While there are experts that agree and disagree with the WHO’s prediction, this is the best guess we have right now.
But that isn’t even the end of the story. The newest data shows that there may be a different fatality rate depending on your health, age, or sex. Like the flu, the fatality rate seems to jumps drastically for those who are older and in poorer health.
So how does this fatality rate compare to other diseases we have seen? The seasonal flu, for example, has a fatality rate of below one percent -- relatively in line with what the WHO predicts the coronavirus fatality rate to actually be.
If this is the case then, why are we all so scared?
There are two very important reasons. The first is that we are pretty confident that the seasonal flu’s mortality rate is directly correlated with your individual health meaning the only way you die from the seasonal flu is if your health is already very compromised. While the newest research indicates that coronavirus tends to follow relatively the same pattern, we have heard of cases of coronavirus where this is not the case.
Second, coronavirus appears to be more highly transmissible. For example, if you have two people, one infected with seasonal flu and one infected with coronavirus, the person with the seasonal flu will infect just one person for every (almost) three people the coronavirus infected person will transmit the disease to. Coronavirus could be almost three times more transmissible.
But here is the real deal -- all of these numbers are based on predictive models from very, very limited data. And a significant amount of the data that came out of China is highly suspect.
So what does this all mean? It means that coronavirus is serious and that while you should take precautions we really don’t have any idea of the real impact of coronavirus. As with anything, the unknown is by far the scariest part.