All respiratory viruses follow a bell-shaped pattern

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By Larry Quick

Sixth in a series

The previous article is at thevoice.us/variations-may-make-it-difficult-to-assess-covid-19-deaths

Risk is the possibility or probability of an occurrence. Human beings confront the risk of death every day. The CDC (Centers for Disease Control and Prevention) has calculated that the risk of dying from the influenza for an infected individual is .01%. It represents an influenza infection lethality rate of 1/1000 cases. How does this compare to the lethality rate of COVID-19?

In the flu season, October 2019 through April 2020, the U.S. was hit by three respiratory viral epidemics. The first epidemic was Influenza B which peaked in December 2019. The second epidemic was Influenza A which peaked in February this year. The third epidemic was the SARS-CoV-2 virus which peaked in March this year. The progress and decline of these three respiratory viral epidemics has been charted by the CDC and can be viewed at bit.ly/2Rt8T6c. Influenza B, Influenza A, and SARS-CoV-2 are all considered respiratory viruses because they infect our respiratory system, the parts of our body that we use to breath.

All respiratory viruses follow a bell-shaped pattern of introduction to a population, a rise in new daily infections, a peak in new daily infections and a decline in new daily infections. That all viruses follow a natural bell curve, with slopes roughly equal on the way up and down, was discovered by Dr. William Farr more than 100 years ago, and it’s known as Farr’s Law.

A viral infection typically takes three to five weeks to build to its peak daily infection level, and about three to five weeks to diminish in its impact on a population. This doesn’t mean that the virus disappears from the face of the earth. What it does mean is that the infected population has developed sufficient immunity to the virus. The virus has run out of individuals susceptible to infection and thus capable of transmitting the virus to others.

To provide a graphic picture of the flu season, as it progresses from its start in October, through its end in April (and beyond), the CDC has created the ILI Activity Map. ILI stands for influenza-like-illness and tracks Influenza A, Influenza B, SARS-Cov-2 and any other influenza-like-illnesses. To use the ILI Activity Map go to gis.cdc.gov/grasp/fluview/main.html.

For the past 16 weeks, ending August 29th, Illinois has been Dark Green on the ILI Activity Level Map. On the 13-level scale, Dark Green represents the lowest possible level of influenza-like-illnesses for a seven day period. Yet each week the IDPH (Illinois Department of Public Health posts approximately 10,000 newly-confirmed COVID-19 cases. Where are all of the sick and infectious COVID-19 patients in Kane County and the rest of Illinois?

For the 2019/2020 flu season, the U.S. population fatality rate is approximately .02% (2/10,000). How does that compare to COVID-19? Below are U.S. COVID-19 population mortality rates by age group:

• 65+ (.04%) = 4/10,000

• Under 65 (.01%) = 1/10,000

• Under 49 (.003%) = 3/100,000

• Under 29 (.0003%) = 3/1,000,000

• Under 17 (.00003%) = 3/10,000,000

Source from the CDC: bit.ly/32rz43x.

Per the IDPH, the COVID-19 mortality rate for Kane County is approximately .06% (6/10,000), from www.dph.illinois.gov/covid19

Given the above COVID-19 mortality rates, and that the ILI activity map has shown minimal influenza-like illness in Illinois for the past three-and-a-half months, it may be possible for State residents to contemplate a return to the old normal.

Continued at thevoice.us/vitamins-c-and-d-safe-drugs-can-help-avoid-covid-19

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