> The mRNA vaccines don't have any impact worse than a sore arm.

Lets not go too far with statements like that. People with history of allergic reactions are told to not take it, and the Pfizer–BioNTech mRNA has a rate of about eleven cases per million doses of vaccine administered.

As with any medicine, there are a risk/reward aspect to it. If you take a over-the-counter pain pill there is a small but detectable risk of getting a serious side effect. Most people still take it because the reward out weight the risk.

I would rather go with the carrot then the stick when it comes to getting people vaccinated. Getting a vaccination protects against some of the really unlucky consequences of covid, including permanent injuries like decreased lung capacity. The risk involving the vaccine is to my understanding much lower, so the math comes out in favor of the vaccine.

> People with history of allergic reactions are told to not take it

Then they should not get the vaccine and be shielded by herd immunity. There are also several other illnesses which are not compatible with vaccinations but the number of those people are small. So healthy people should partake in the vaccination as for them, the risk-reward ratio is definitely worth it.

> So healthy people should partake in the vaccination as for them, the risk-reward ratio is definitely worth it.

How can you make this decision for someone else?

Risk reward ratio is not a decision, it’s an objective measure. It’s a different question what and how can be forced on people, but the issue is clear: healthy people should get vaccinated.

> Do you know everybody’s medical condition?

Does a layperson know about how his/her condition is relevant to vaccination? No. They will ask a doctor about that - who will give them an answer whether they can or can’t get the vaccine. And I’m not even living in the US, I’m just not crazy and know that it is the only way to protect ourselves and our community.

> Does a layperson know about how his/her condition is relevant to vaccination?

Hmm, maybe this is what you do, but do you really thing everybody goes to the Dr for everything? Some people are well within the means of deciding for themselves, some not. And when you have the “top” Dr in the nation failing to build trust by opening his mouth before he’s sure then all sane people have is themselves. It’s insane to me how many people blindly trust the vaccine when we have new information nearly weekly about how it effects different cohorts differently. But we’re sure it’s safe right? No, the reality is people don’t care if someone gets the vaccine and dies, “just do your duty”. I’m good.

> The disease can and does have severe and sometimes long-lasting impacts on young healthy people.

The context that we were discussing was "achieved herd immunity, epidemic goes away". In that context the healthy young people do not get any severe and long-lasting impacts, because they don't get the disease at all, thanks to the herd immunity provided by mass vaccinations.

> And we aren't getting to a herd immunity level of vaccination if young people are unvaccinated.

This is true. If you were to say "it's your responsibility to take a vaccine, even though the risk/reward ratio is bad", then that would be an argument that I would respect. However, that's not the argument you're making. You're trying to claim that the risk/reward ratio from a personal standpoint is good, which I disagree with.

> The mRNA vaccines don't have any impact worse than a sore arm.

This is false. I personally know people who have had considerable side effects from the vaccine ("getting sick").

That said, I'm personally taking the vaccine today.

> The mRNA vaccines don't have any impact worse than a sore arm.

This is just logically untrue. The absolute most you can claim is that "these vaccines don't have any impact worse than a sore arm, that we know of, within the 18 month period that they've been available". Neither you nor anyone else can speak to long-term effects until we wait it out and see, nevermind true "unknown unknowns".

But why are we only considering vaccination with regards to herd immunity. Shouldn't we also be including natural immunity from previous covid infection?

Because, for example in Canada, there have been 1.4 million total cases of Covid over the last year which has on multiple occasions stretched particularly ICU capacity to the limit. In a much shorter time period we have administered 27.7 million doses of vaccines. We give more doses every 3 days than we had cases in 14 months. Natural immunity is almost negligible compared to vaccination. Getting to herd immunity levels with actual infection will result in hundreds of thousands of deaths and damage our health (and healthcare system) for decades.

It has been demonstrated that repeated infections are possible and may be common. And there are a large number of variants in the wild that are not hindered by immune systems previously exposed to other variants. Allowing the virus to spread in populations causes even more variants to emerge.

Even vaccines provide reduced protection from new variants. I read today that most effective vaccine only provides a ~70% chance or so of protection from the Delta variant in the UK. Hence the talk of booster shots before the initial vaccines were rolled out.

Herd immunity comes from vaccination. It's not really feasible for it to occur naturally because the virus will continue to mutate and reinfect people indefinitely.