mekka okereke Jul 11, 2023

Sharing in case this helps someone.

The last time someone in our household got Covid, we were able to keep it from spreading to anyone else. ♥️🙏🏿 This time we were not so lucky. My Covid high score streak is finally broken! Rona got me y'all!

Completely unscientific observations of how this thing looks to have beat our mitigations:

Day 0: Contagious. No symptoms. Negative tests.

Day 1: Contagious. Slight symptoms. Negative test.

Day 2: Contagious. More severe symptoms. Positive tests.

Show threadmekka okereke Jul 11, 2023

Our family doesn't eat indoors, doesn't go into buildings unmasked, wears masks in dense outdoor situations, wears a full elastomeric mask when flying.

For the past few weeks, even when outdoors, I've seen a few friends coughing, and I immediately put my mask on. They then say, "No dude, relax, it's not Covid, I tested this morning!" And I said, "🙅🏿‍♂️ Sure! That's what 'Rona *wants* me to think! 😷" 4 friends this happened with, and all 4 tested positive the day after their little coughs.

Show threadEarthling
@mekkaokereke Thank you for making the point that people are contagious *before* testing positive for Covid. I hope your recovery is full and fast.
Jul 11, 2023 at 11:15pmWeb
Show threadThe Animal and the MachineJul 12, 2023

@earthlingusa Thanks.

People like simple stories but life isn’t simple. Covid was thought by science to not be contagious before a positive test. This was probably correct.

Unsurprisingly however evolution, a logic process hasn’t stopped, and a strain that IS contagious before positive signs has spread faster and is now dominant. Science was best efforts correct and still is best efforts correct but things have literally evolved.

The only plus side going for us is that we do have an immune response so one strain has an inoculation effect against similar strains. What this means is that evolution pressures for virulence over severity. So a faster spreading less damaging version takes over the opposite. This is how we move to endemic.

However, you are not a statistical average and you CAN do things that help. Listening to @mekkaokereke is one of those things.

Show threadGwynJul 12, 2023

@taatm @earthlingusa @mekkaokereke We knew from the start that COVID had a long incubation period (<= 14 days) during which others could be infected. Which is why anyone who was paying attention knew what was coming - terrible set of parameters for a virus.

There is also no guarantee that COVID will become more "mild" - evolution is random and all it needs to successfully mutate is to infect more people. As long as they infect lots of people before they die, it can quite easily get worse.

Show threadThe Animal and the MachineJul 12, 2023

@nikclayton
@earthlingusa @mekkaokereke

Specifically, I was referring the UK tests available in 2020 that was believed would find you as positive when you become contagious, regardless of symptoms of which there may not be any. I.e. negative test is probably safe. This may have been found to be untrue, I don’t know.

We are now fairly sure in the UK today that you will be contagious before you test positive. Again, not taking about symptoms. 😷 You might not even show symptoms.

@GwynHannay does make an excellent point about the future being unknown. Entirely correct. Endemic is what usually happens but no guarantees. None.

Show threadNikJul 12, 2023
@taatm we had a good idea it was contagious before symptoms appeared back in April 2020. https://www.sciencenews.org/article/coronavirus-covid-19-infection-contagious-days-before-symptoms-appear
COVID-19 may be most contagious one to two days before symptoms appear

The coronavirus probably spreads the most before symptoms appear, making containing viral transmission harder.

Science News
Show threadTJ RadcliffeJul 12, 2023
@nikclayton @taatm Also,
there is no selection against severity. More virulent strains may be less severe, or they may be more severe. Equal probability, or so close as to make no difference. And immunity wanes in a month or three, even to the strain you were infected with. There is no lasting immunity to covid, from vaccines or infection. Clean air is the only thing that will get us out of it, and masking cleans our personal air. https://worldofwonders.substack.com/p/what-can-a-seirs-model-tell-us-about
What Can a SEIRS Model Tell Us About Covid?

the parameters of the pandemic

World of Wonders
Show threadThe Animal and the MachineJul 12, 2023

@tjradcliffe @nikclayton
I’m happy to be wrong but as I understand it, the main selection is on virulence, but the ones that spreads the most are the ones where the host is asymptomatic, which by definition is less severe. Additionally, severe infections remove the human from the pool, especially in death.

So yes the driver is virulence but with a secondary pressure to severity being reduced.

Totally agree about the 50/50 random on the mutation, but a new strain that puts the most ardent anti-masker in bed will not spread as well as the new strain that makes them feel ok enough to get on a plane and cough a lot.

Show threadTJ RadcliffeJul 12, 2023
@taatm @nikclayton Timing is everything, and there are many dimensions at work. For example, a new strain that is twice as virulent, asymptomatic for a week, and then kills the host 10% of the time will be selected for over a strain that is 10% more virulent but has nasty symptoms on day 1. Sure, there are *possible* scenarios where severity is selected against, but they are a tiny fraction of the total range of possibilities. Not worth focusing on, in my view.
Show threadThe Animal and the MachineJul 12, 2023
@nikclayton
I need a quote tweet. I don’t quite agree with @tjradcliffe about evolutionary severity pressure but I do think there is a good chance he knows better than me so please read the reference material he shared.