The answer to your question is in the article. This is not an attenuated virus, nor is it variolation, it's a modified other virus (common cold) with some proteins added and does not cause an infection, it just stimulates antibodies.

It has been heavily modified, first so it cannot cause infections in people and also to make it "look" more like coronavirus. Scientists did this by transferring the genetic instructions for the coronavirus's "spike protein" - the crucial tool it uses to invade our cells - to the vaccine they were developing.

The problem is not the vaccine, it is when you actual contract COVID-19 later on. If the vaccine sufficiently suppresses the symptoms, but doesn't actual prevent infection, there is a change you can spread the virus asymptomatically.

I see how that's important. On the other hand, it's not as big of a deal to spread the virus if everyone has protection from the symptomatic risks. We should still shelter in place, but even turning active cases into carries would reduce loss of life (presuming we continue regular testing so people can KNOW if they are a carrier)

> On the other hand, it's not as big of a deal to spread the virus if everyone has protection from the symptomatic risks

Assuming everybody got the vaccine in the same instant, which they would not.

> We should still shelter in place, but even turning active cases into carries would reduce loss of life (presuming we continue regular testing so people can KNOW if they are a carrier)

We've all seen how people are behaving right now: "Oh I'm young, forget about grandma". How do you think they'd behave knowing that they've been vaccinated? It's important to consider the sociological conditions in which an intervention is deployed. Unfortunately, our present society has a very large number of self-centred individuals.

This is a great way to turn the anti-vaxxers, hahah.

The more people take the vaccine, the less society bothers to social distance and other low-tech things, the more dangerous not taking the vaccine becomes.

> It has been heavily modified, first so it cannot cause infections

Amusingly, lives would probably be saved if they had kept the base virus used for vaccination infectious. It's just the common cold, and the side effects are currently only a headache and fever, so getting the vaccination virus secondhand would be better than getting coronavirus, and you'd be protected after.

Common colds can occasionally be serious for people who are severely immunocompromised in other ways.

If everyone gets the vaccine then does the distinction matter? Genuine question not rhetorical.

Even if it's made mandatory, which may not happen, manufacturing and distributing enough vaccines for everyone to get one will take years. Ideally we want to get everything back to normal once we have enough vaccines stocked up to strategically deploy in hot spots, but if the vaccine doesn't severely reduce the disease's spread that strategy won't be effective.

a) It would take months not years. b) you don't need to have _everybody_ vaccinated.

If vaccinated persons still transmit the virus, I would think herd immunity is irrelevant. Am I incorrect there?

How can you transmit a virus which is not able to use your body to replicate itself?

I suppose technically, if you were actually just as contageous as a sick person for as long. Hard to believe that would be the case though.

Logistically you can't give everyone the vaccine at the same time. If immunity is only temporary (few months) front line hospital staff are likely going to get vaccinated before the rest of society.

It would matter for those who can’t be vaccinated (the immuno compromised, very young children) or for those whom the vaccine might not be effective (very elderly with weak immune responses)

It would also matter for eradicating the virus. If it keeps circulating, and vaccines only provide protection for less than a lifetime, then we will have to keep vaccinating just about everyone in the world indefinitely. Any place that falls into civil strife could also expect a virus outbreak eventually.

It would still be great to have vaccine that merely made the virus without effect! But eradication would be better.

> then we will have to keep vaccinating just about everyone in the world indefinitely.

Which is to say, it'll be like the seasonal flu and not a pandemic. Yeah, we can tolerate that.

Well, it really depends on the timeframe. If we need a new one every two years, no problem. If every six months, that’s worse.

Current flu vaccine coverage is 24-50% depending on jurisdiction, once per year. So, aiming at, say, 80% coverage twice per year would be 3-6x the current level of flu vaccination effort.

Not awful, but tiresome.

You don't need 80% coverage though. Influenza would be a pandemic too (and has been!) but is well controlled by the existing regimes. There's nothing all that notable about covid really, beyond its novelty. Once the bulk of the population has some immunity, even if incomplete and even if it needs a regular refresh, we hit herd immunity: R0 drops below 1 and the disease stops spreading. There's no reason to expect this to work any differently.

There are a lot of diseases that everybody gets vaccinated for routinely and regularly. I thought the assumption was this was going to be one of those, it is just a (currently unknown) matter of how frequently you'd need to get it.

Are any epidemiologists talking about possibly eliminating it completely? Seems like the toothpaste is out of the tube for that.

Yes. Devi Sridhar has mentioned it as a goal, fairly sure I have seen others.

We have only eliminated one virus globally (smallpox) but plenty of others have been eliminated nationally. Then to travel to those countries from a country where the disease is endemic you generally need proof of vaccination.

There are also many countries that have basically eliminated the virus at present. They’re not going to want to import the virus just because other countries failed.

Once you have two things the probable future becomes clear: a vaccine, and very fast tests. Combined, they will make it fairly easy for a well governed country to eliminate the virus.

Then, any entering traveler from an endemic country would require proof of vaccination and a quick test at customs to confirm. That would keep the virus out of eliminated countries.

After that it would be a global effort to eradicate the virus country by country, just like we’ve been doing with other diseases such as polio.

A key feature of sars-cov-2 is that it is not like the flu. Coronavirus spreads in clusters and this is containable.

and also, how much time one people will be imune, and if new doses will be needed to reinforce the response of the imune system. People are saying September as a date for the vaccine to be avaliable, but it seens to be still many questions to answer before that.