Covid vs the Flu

 

Elderly and people with significant health conditions should be extra careful, but the rest of us can take reasonable social distancing and hygienic precautions and not expect to have greater risk than the Flu.

 Covid is New

 A key point to understand before looking at the risk related to Covid and comparing it to the Flu is that the the US population has, essentially, a naïve immune system when exposed to Covid.  While there is some possibility that there is some limited immune system memory due to previous corona cold virus exposures, there has been no exposure to Sars Cov2.  This is different from the Flu, where there is essentially a primed immune system from the combination of vaccinations and previous exposures to somewhat similar viruses.  As shown below, in 2019 54% of the population received the Flu vaccine and more vulnerable populations have a higher incidence of vaccination (0-17y 50.4%, 18-49y 34.2%, 50-64y 46.8%, 65+y 68.7%).

Covid has Similar Mortality Rates as the Flu (but because it is new we need to be more careful)

 To determine the fatality rate of Covid experts first estimate how many people had Covid based on seroprevalence data (measures of antibodies in random samples of population).  This number is often greater than the number of persons testing positive as there are many asymptomatic cases that never suspect they are ill and never get tested but never the less they still formed antibodies.  These number of cases are then used with the number of Covid deaths to determine the fatility rate.  The CDC estimates the following fatality rates: 0-17y 0.003%, 20-49y 0.02%, 50-69y 0.5%, 70+y 5.4%.  The WHO estimates the overall facility rate is ~0.14%.  While for some reason the CDC uses somewhat different age brackets for the Flu, the CDC has very similar fatality rates of the Flu: 0-17 0.006%, 20-49 0.02%, 50-69y 0.5%, 70+ 5.4%; and has an average fatality rate of 0.14%.   Covid does appear to be more dangerous to the elderly, but it is possible that there may be some selection bias as older people with significant health conditions are more likely to get Flu vaccinations but there was no vaccine available for Covid.