Current research shows that the previously infected’s antibodies are equal-to or better than the vaccine. So previously infected should be sufficient, yet I expect these companies not to care about that
So that is not the case in US and you still have to get a vaccine? Or is it simply because there is no "proof" that you have been previously infected?
Most EU countries (that I checked - Austria is an exception) don’t even recognise the presence of antibodies as proof of past infection.
In other words, there's strong evidence that you get a stronger immune response, for longer, that is more effective against variants with the vaccine than with a natural infection. The paper I think you're referring to (https://www.medrxiv.org/content/10.1101/2021.06.01.21258176v...) states "It is not known how well these results will hold if or when some of the newer variants of concern become prominent. However, if prior infection does not afford protection against some of the newer variants of concern, there is little reason to suppose that the currently available vaccines would either. Vaccine breakthrough infections with variants have indeed been reported [17]", but this is directly contradicted by some of the other studies I cited, that to show better protection against variant re-infection.
> previously infected’s antibodies are equal-to or better than the vaccine
Better how? If they still get reinfected (and they do) then how is this quantified?
The simple reason being that the vaccines have the spike protein as a marker - the part of the virus that we expect is least likely to change significantly.
What we do know is that the current Delta variant, which is a fitness escape but also partly an immune escape, has infected a number of people that had the vanilla variant.
[1] https://twitter.com/ENirenberg/status/1412865782862725125
There is this study: https://www.nature.com/articles/s41591-021-01377-8 saying that natural immunity seems to be slightly worse than Pfizer or Moderna vaccine, but better than AstraZeneca or Johnson vaccine.
Vaccines and prior infection train the adaptive immune system to recognize pathogens so that the body can begin fighting the infection sooner. Some people's immune systems work less well than others, or due to situational factors, a person is more susceptible to infection and they become sick. People with immunity generally do far better at fighting the infection, being less ill and recovering faster.
Nothing is perfect. Vaccines are better than getting sick or doing nothing.
Time between infections and mutations.
At worst it does nothing, at best it helps. I don’t see why google should bother with an exception here.
For a big chunk of the population vaccinating is very safe because the virus is very dangerous. A vaccine doesn’t have to be very safe for a disease that kills on the order of one in a thousand off otherwise healthy adults.
Being very young or already having contracted the virus significantly alters it’s risk profile. With a virus several orders of magnitude less deadly you have to start being much more careful that the vaccine is provably considerably safer than doing nothing. That’s not hard when you’re trying to beat 1 in 1000. It is very hard when you’re trying to beat a one in millions risk.
There have been concerns and side effects. Much less amplitude in signal compared to the virus, but still big enough to halt briefly a few of the vaccines, still enough that small children don’t get emergency authorization, still enough for a few warnings about immune reactions.
It is very rational to take a one in a million risk to prevent a one in a thousand risk. It is very rational to pause before taking a one in a million risk that could very well prevent nothing.
From my experience, the immune reaction to the vaccine after having had the infection is an order magnitude worse than what the brochures and previously uninfected people say.