[lnanek2]

It wouldn't. Their immune system already has a sample of the virus. Giving them a vaccine would give them nothing they don't already have.

The idea behind a vaccine is the give the immune system a sample before it encounters the real virus, which allows it to respond quicker when the real virus arrives, which allows it to prevent the virus to replicate sufficiently to make the person sick.

For someone who already has the virus, the vaccine won't do anything.

[dagmx]

This is somewhat incorrect. Not all vaccines include a sample of the virus they're protecting against (see the mRNA vaccines for covid-19).

Also for some viruses (again see covid-19), it's still advisable to get a vaccine even if you've already been infected. The protection rate and longevity of the vaccines can outweigh infection based antibodies dramatically.

In the case of HIV, it's potentially quite different, because HIV is such a unique disease, that yeah, a vaccine might not help anyway. But otherwise, your comment doesn't apply to vaccines in general (and it didn't seem like you were replying towards any specifics of HIV)

[da_big_ghey]

Vaccine for coronavirus recommended for its immune-building benefit even in persons who had infection, this is to reduce likelihood for more infection in the future. I am doubting that this applys on the HIV since nobody is getting it then beating the infection, just supressing it.

[jonplackett]

Also some evidence that vaccines are helping with long covid https://www.theguardian.com/society/2021/may/18/long-covid-s...

The difference with mRNA vaccines is they let your body build antibodies without it even knowing the virus itself

[whimsicalism]

Long covid is not sufficiently studied to indicate whether vaccines help.

Many of the patterns associated with long covid suggest that is a mix of one condition that has a mechanism probably similar to chronic fatigue syndrome and the other is the manifestation of long term sequelae that is common with other respiratory viruses.

My guess is that the vaccine might help with the CFS-like symptoms.

[Unklejoe]

> Also some evidence that vaccines are helping with long covid

By what possible mechanism? Does this imply that long COVID is a result of some small amount of lingering virus?

I was under the impression that long COVID was a result of damage caused by the initial infection - not some continuous infection of the actual virus.

[Vecr]

It probably is not really doing anything, I would think replacing the nocebo of being infected (or supposedly being infected) by SARS-CoV-2 in the past with the placebo of getting vaccinated (more recently, so you get a recency bias boost) makes up most of the "helping". If not that exactly a similar psychological re-targeting effect is probable.

[nicoburns]

It's still unknown what causes long covid. Lingering virus is one hypothesis that's still plausible. Indeed some people believe it precisely because the vaccines seem to be helping significant numbers of people (but not everyone, they can also make it worse for some people).

[whimsicalism]

A substantial proportion of long covid cases share similarities (particularly demographics) with other syndromes of unknown mechanism, particularly chronic fatigue syndrome.

[markenqualitaet]

I don't think it works this way with HIV. As you stated having immunity to a specific HIV presentation does not prevent infection. Any vaccine effective would need to make the body see a pattern it cannot find on it's own. Something universal to HIV, which cannot be evolved around.

This is different from other disease where the immune system doesn't have enough time to response before the disease kills/damages the body.

If the vaccine can prevent HIV signature evasion, it may very well help control/treat the disease, I think.

[Uberphallus]

Some vaccines are effective after infection; it's called post-exposure prophylaxis. Some examples are tetanus and rabies.

[amluto]

Depends on the vaccine. There are research programs to develop vaccines that induce people to make broadly neutralizing HIV antibodies. Most people don’t naturally produce these. Such a vaccine could plausibly help people who are already infected.

[koheripbal]

This is true for many vaccines, but given the unique mechanism HIV uses to attack the immune system, it might actually work in actively infected HIV patients.

[hfkrjfjfj]

> It wouldn't. Their immune system already has a sample of the virus. Giving them a vaccine would give them nothing they don't already have.

What you said applies to most viruses (flu, corona, ...), but not to HIV.

There is a reason we failed to create a HIV vaccine for 30 years, and that reason is that simply presenting the virus just doesn't work.

So this vaccine uses a new quite amazing methodology, instead of presenting the virus, it presents something else designed to trigger the 1 in the million B cell from our bodies which are actually capable of producing a neutralizing antibody. Regular vaccine trigger randomly the other 999999 B cells which produce useless antibodies.

Typically that process takes 10 years for a HIV infected person, after which they produce the proper antibodies.

This approach is called germ-line targeting, and tries to accelerate that 10 year process in 2-3 shots.