More good news. It seems that each day, the results of another study of the actual extent of Covid 19 infection show that the actual number of people infected is much greater than we expected.
As always, this is good news.
Until now, Miami-Dade county in Florida has reported 10,600 cases of Covid 19. However today, a University of Miami reported on a study designed to determine the actual extent of infection by selecting a wide range of patients with and without symptoms for antibody testing.
They found that 6% of those tested were positive for the antibody. Assuming that their study group was representative of the Miami Dade county, this would mean that 165,000 were infected with Covid 19 instead of the 10,600 reported. About 50% of the people tested reported having no symptoms for 14 days before being tested.
This data is consistent with the data reported for Santa Clara (2-5 %) and Los Angeles County (4%) in California and New York (up to 21%) as well as testing in Robbi Italy (10%) and Gangelt Germany (14%). Although each study tested only a few thousand representative people, in all cases, the number of people tested ranged from 4 to 21% of the population- representing 10 to 80X the number of cases that have been reported.
This means that the ‘curve’ that we have been trying to flatten is NOT representative of the actual number of infections that have occurred. Taking an average of 5% infection for discussion sake, this would mean that in the US alone, there have been 18,750,00 infections, not 953,851. This would also make the fatality rate .28%. If it turns out that 10% of the population was infected, the fatality rate would be .14%. Recall that New York city reported an infection rate of 21%.
Caveat: All of these studies represent cross sections of different areas of the US, Italy and Germany. More data is necessary from many more places with wider demographic of study subjects until the actual infection rate is known.
However, even as we watch the daily count of new cases increase, it is certainly the case that the cases being measured are 10 to 80 times less than the actual number of people being infected. Again, this is good news. It means that 50-80% of the people who get infected have no or minor symptoms and that the fatality rate gets closer and closer to the values we associate with seasonal flu. This is especially good news as the seasonal flu numbers are WITH a flu vaccine. To date, there is no proven vaccine for Covid 19. The numbers for Covid 19 can only improve with more antibody testing and the introduction of a vaccine.
This also has implications on reopening businesses as sheltering in place may have been effective, but perhaps not nearly as effective as it was thought to be.