Back then, diagnosis was based on signs and symptoms. Today diagnosis is based on a diagnostic test, which is even given to people showing no symptoms.
During the Spanish Flu, there was an initial peak in the spring, and then a huge peak in the fall of 2018. Another peak formed in the spring of 1919.
I posted excerpts from my Grandmother’s 1918 “Spanish Flu” diary entries. which makes for interesting reading. The “innoculations” she discussed were then based on the erroneous idea that the flu was caused by bacteria and thus the innoculations were ineffective. The Spanish Flu pandemic ended on its own, just as many pandemics have done. Vaccines, if deployed fast enough, can also bring a pandemic to an end without as much illness and mortality.
With Covid-19 so widespread and prevalent it seems Covid-19 may run out of steam due to natural causes and before vaccines are widely deployed (by the last half of 2021).
Here is the epicurve for the U.S., from today’s CDC update:
With so many daily new cases (and estimates that several times more cases are not tested), it appears we are, in some sense, approaching herd immunity (HI) effects. Dr. Scott Gottlieb suggested 30% might have had Covid-19 by end of 2020.
With additional cases every day in January (probably a million or more every day) plus the early phases of vaccinations, by February, 40-50% of the population might be immune. Past research suggests 30% of the population might have immunity to SARS-CoV-2 before the pandemic, for as yet undetermined reasons. If true, then we are potentially nearing a mostly natural HI in the next few months.
I am optimistic we are seeing HI effects in selected regions already. HI does not mean that the disease vanishes, but that as more and more have immunity the disease has a harder time transferring to another person, so the new cases gradually diminish.
But remember, I am idiot with no health care background. I make observations and ask stupid questions. My comments are for entertainment only.