There's some mention of the virus possibility losing out on it's lethality, which is certainly possible but as other posters pointed out, there are different strains around the globe and the statement if indeed true shouldn't be taken as a blanket statement for the entire world.
What's interesting that I'd like to point out, particularly in the context of rising numbers in some states, is the conversation I had with a friend of mine a few days ago. He is a critical care pulmonologist in Long Island, NY where I live (just outside of NYC). Essentially he is on the front lines of the front lines. When I picked his brain over his experiences in the ICU with Covid patients and specifically his thoughts on why some younger individuals succumbed to the disease he mentioned the following points that to me, at least, sound logical:
1) The vast majority (not all) of younger people who succumbed to the disease had at least one of the following pre-dispositions: Obesity, diabetes or history of Vapping. They were essentially, relatively speaking, unhealthy to a degree. Individuals suffering from diabetes in particular are inherently prone to health related complications that non-diabetics typically don't experience or overcome much more easily without complications. Same with Obesity as obesity typically goes hand in hand with diabetes and are inherently linked. There is no need to explain why Vaping (or any type of smoking for that matter) should be considered a predisposing risk factor to increase mortality rate of a respiratory infection of any kind. But he did say that, although rare, there were some younger individuals with absolutely no predisposing medical conditions whatsoever that succumbed to the disease. This bring me to point #2
2) To put it simply, he stated that during the height of the pandemic in March and April, they literally just didn't know how to manage the severe version of the disease. Meaning they aggressively placed patients on ventilators too quickly once their O2 saturation started to drop. In hindsight, after essentially what can be considered trial and error, it is now accepted medical knowledge that people placed on the ventilator have a much higher mortality rate as compared to those who can avoid the ventilator. As a result, he stated they now "take their time" with patients and only place them on a ventilator once a very critical 02 saturation level is reached. Because of this change in treatment protocol, we now see the death rate dramatically dropping in NY state (as of yesterday we had our first day of no Covid related deaths).
As with any newly discovered disease, there will be unfortunately deaths related to mismanagement and the novel nature of the disease in question. Studies are now further confirming (and I believe the CDC also corroborated) that the mortality rate is considerably lower than initially predicted (about 0.3% for those over the age of 65 and much less for younger individuals). We are getting a better understanding and handle on this disease, which BTW is part of the family of the common cold, and things perhaps may not be as doom and gloom as previously thought.
For me personally, when I see the number of cases continuing to increase but there isn't much chatter of the death rate, I'm going to interpret that as a great sign. The question still remains how society, politics, the media and public health deals with the potential 2nd wave in the fall. Logic points to the fact that there will be a 2nd wave. Did we learn enough these past 3 months to now understand which strategies and protocols need to be put in place to properly control this virus? I personally think so, and while I anticipate the number of cases to start rising come around November/ December, I think we will see much less death and chaos. What happens late 2020 will tell us everything we need to know moving forward (especially after November 3rd, when the election is over
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