Why would we need that? I think a lot of people will get immunity the natural way, even now a lot of people are having covid w/o any symptoms at all, and they will have immunity.
> A vaccine is also an attenuated version of the virus so if becoming immune from the virus doesn't last long it won't last long from a vaccine.
A vaccine can be an attenuated virus, or a piece of mRNA or DNA, or a distinctive viral protein. Which type of vaccine you use+the adjuvants that go with it can result in very different immune responses and efficacy over time.
> This is false, immunity is strong and long-lasting.
Immunity to COVID-19 varies a lot person to person and is poorly understood. It does however appear that many people can be reinfected (especially people who had mild symptoms the first time.)
A well documented one: https://www.news-medical.net/news/20200720/Doctor-in-Israel-...
I looked at the sources for that article you posted and not one of them supported your claim. Not one. I even went several articles in because news medical dot net was using itself as a source.
There's no consensus at all, even remotely. I have no idea where you got that other than fear based news reporting.
I'm not going explain immunology to you but 99.9999% of viruses on the planet build long-term immunity if you survive. Coronavirus is the same way.
To put it another way..vaccine immunity operates the same way as infectious immunity.... do you think they are going to invest billions of dollars into a vaccine if immunity only lasts for a few months?
>mRNA is part of a pathway that creates a protein that is on the virus which the immune system reacts to.
>Please post your source saying that people can be re-infected.
And let's say everybody get vaccine in 2 weeks period of time, if the immunity doesn't last at least few years what's the point of this mass vaccination then.
Nothing has this kind of success rates. Vaccine, if effective, reduces risk of vulnerable groups and transmission from their caretakers. Exactly like flu vaccination.
Heck, we have failed to eradicate polio in all countries, a level 1 virus much easier to control. I predict zero chance we can eradicate a level 2 virus right now.
Having COVID without symptoms (asymptomatic) does not mean that you are immune and you are still infectious.
Edit:
> even now a lot of people are having covid w/o any symptoms at all
The last estimate I saw (last week I think) for Stockholm was that only roughly ten percent of the local population had COVID,
It is just mild enough. There's another one alphacoronavirus in about 5% of colds that is much worse. (Not counting SARS group.) Mind you parallel infection with multiple viruses is common.
It's hard to estimate prevalance because PCR testing has a large false negative rate. It depends highly on which day of the infection you're tested and even then the peak rate is still quite miserable for trying to find it.
Serorevalence is also tricky as we trade off false positive for false negative and the antibodies decline after a few months. That's not to say that memory B cells can't spin up production on demand though. Then there's the whole t-cell response which may play a bigger role in asymptomatic cases. All in all, its understood that antibody testing is underestimating infection rates.
Regardless of what values we think herd immunity should have, it's pretty clear that places like Sweden have seen the death peak and then tail off without any major change in distancing policies. If anything, people are relaxing more with time.
edit: I should mention that since march, we do have better treatment options and we have stepped up our game protecting care homes all over the world including Sweden which saw a majority of deaths from those facilities. This is why it's important to look at trends in other countries as well.
So at best it will be a perpetual game of cat and mouse, like it is with flu, but with higher stakes.
And even if everybody did recover, there's the economic cost of an infection. Productivity missed because workers are sick at home, or worse in a hospital being cared for.
I'm not sure what the dollar figures are, but I would not be surprised if vaccinating a large population turns out to be significantly cheaper than having a small percentage of that large population in ICUs for weeks on end.
Because best case 0.1% death rate times best case 50% required for herd immunity times 7.8 billion people is 3.9 million dead people. And that's pretty bad.
Sweden Italy and New Zealand have already hit herd immunity. They're done with the virus and didn't have 50 percent.
And before you post that they have a few cases recently... understand herd immunity doesn't mean the virus is gone...it just means the virus has nowhere to jump to... so there will always be a smattering of cases.