I understand how it is calculated from the studies. My question is does it translate to each vaccinated person is protected 90% of the time (I'm just using 90% as an example) or 90% of vaccinated people are protected 100% of the time. The discussion early yesterday was saying that if you are vaccinated, the more exposure you get, the higher likelihood that you get infected and/or get a severe case. I'm not sure if that is true and am thinking that if you are an individual that the vaccine "works" on, it won't matter how much you are exposed, you either won't get infected or your case will not be severe.
That's not how it works with other viruses. Even when your immune system knows what to do, like via vaccination or previous infection, if the viral exposure is high enough it can still overwhelm your body's ability to put up a sufficient response. Additionally, if your immune system is off its game (fighting off another infections/injuries, autoimmune conditions, medications, stress, insufficient rest, etc) then the threshold for a sufficiently high exposure changes. At the boundary, you can end up on either side of the line; given the right conditions. As someone with an autoimmune condition, I have seen this first hand with other viruses. If I am having a flare, I can get sicker with colds than when I am not. Recovery is different.
IMO, this is one of those factors that, in the rush to reassure people about the benefits of vaccination, is not being explained well enough. Virologists, I think assume it's general knowledge and they are focusing on other things. Not realizing how much people are eager to subject themselves to many exposures. People will get infected, test positive, and others will wonder why it's so many. It won't be because the vaccine didn't work, but because of the frequency and intensity of the exposures. It is mentioned in these NY Times articles, but not really explained.
Sorry about the paywall, if you quickly switch to airplane mode you can read the articles.
"Being fully vaccinated remains the strongest protection against Covid-19, but risk is cumulative. The more opportunities you give the virus to challenge the antibodies you’ve built up from your vaccine, the higher your risk of coming into contact with a large enough exposure that the virus will break through the protective barrier generated by your vaccine."
With daily reports of breakthrough infections and the rise of the Delta variant, vaccinated people may need to take a few more precautions. Here’s what you need to know.
www.nytimes.com
"Dose also matters: A vaccinated person exposed to a low dose of the coronavirus may never become infected, or not noticeably so. A vaccinated person exposed to extremely high viral loads of the Delta variant is more likely to find his or her immune defenses overwhelmed. The problem grows worse as community transmission rates rise, because exposures in dose and number will increase. "
The vaccines are effective at preventing serious illness and death, but they are not a golden shield against the coronavirus.
www.nytimes.com