Are there any examples of successful non-vaccine led herd immunity?

[Enrico]

Just that really. Are there any diseases whose circulation has dramatically reduced just by lots of people catching them, as opposed to by lots of people being vaccinated against them?

But if there were it would have to be an illness that having caught it once you can't get it again, which isn't true of Covid-19.

Absolutely. But I'm just wondering if it's ever happened at all.

To some extent chicken pox, in this country most kids don't have the vaccine, so get immunity by getting the disease, and are then protected from shingles as adults.

But that only works because the virus doesn't mutate, and even then it's not 100% effective.

Chicken pox in the U.K. when we get outbreaks in the school nursery setting it doesn’t spread through the wider population because of herd immunity through natural infection in a substantial part of the adult population (so when my ds got it, six other kids at his nursery did but no adults, parents or people in the wider community did and it has a very Hugh natural r number).

We don’t vaccine routinely so basically we control through herd immunity through natural infection which limits out breaks.

Not there is no suggestion here this would work for cv for a lot of reasons relating to things like a higher death rate, uncertainty about lasting immunity but yes when a large proportion of the population has been previously exposed to natural infection it is sometimes possible for this to act as a buffer against large scale community spread.

To some extent chicken pox, in this country most kids don't have the vaccine, so get immunity by getting the disease, and are then protected from shingles as adults.

^ this isn't true, you can only get shingles if you've previously had chickenpox. The virus sits in your body then come out when you are run down or stressed.

I've had both chickenpox as a child and shingles as an adult.

I thought you only got shingles if you'd previously had chicken pox?

Ok, so looks like chicken pox is contained somewhat because lots of people in the UK have had it. Unlikely to kill you though (but shingles down the line can be nasty).

Tbh I think we should vaccinate for chicken pox anyway as lots of countries do.

Spanish Flu - that ended because people had either died or developed immunity.. and/or it mutated.

I suppose the common cold is subject to a kind of herd immunity thing... It's still around, and people still come down with it, but it is generally a very mild illness unless it develops into a respiratory infection or similar, particularly in people with impaired immune systems (when it can be fatal). As there are so many different strains, and they are caused by different types of viruses, we aren't immune to every single one, but past infections have led our body to recognise the "type" of thing that is invading, so mount the immune response with antibodies and t-cells, so it doesn't progress to a more serious disease in most people and goes away pretty quickly.

I've heard that the common cold is thought to have killed people from remote tribes, brought in by missionaries/ explorers etc, when they hadn't been exposed to it previously. Can't find any convincing references to that having definitely happened, though... only to flu having done that, which is generally more likely to be fatal, even with vaccines.

Surely, though, things that we recognise as "serious" diseases wouldn't have herd immunity (apart from through vaccination) or we wouldn't consider them serious... and therefore worth of developing a vaccine. So, yes, as pp have said, it's "only" chicken pox (though that still kills around 20 people a year even though there is a vaccination) but if there wasn't some herd immunity going on it may well be more serious.

@ForeverBubblegum

To some extent chicken pox, in this country most kids don't have the vaccine, so get immunity by getting the disease, and are then protected from shingles as adults.

But that only works because the virus doesn't mutate, and even then it's not 100% effective.

You can only get shingles if you’ve had chickenpox.

@ForeverBubblegum

To some extent chicken pox, in this country most kids don't have the vaccine, so get immunity by getting the disease, and are then protected from shingles as adults.

But that only works because the virus doesn't mutate, and even then it's not 100% effective.

You can only get shingles if you have had chicken pox first, so it most definitely does not protect against shingles.

However what i think you're mixing it up with, is that children who had the vaccine rather than the illness seem to be more likely to get shingles.

I know teenagers aged 15+ and adults in their 20s who have got chickenpox as they didn't get it as kids. They bloody all suffered and one of the adults was hospitalised.

I think the shingles link is that one of the reasons we dont vaccinate in the uk is the children getting chickenpox exposes the adults to the virus again and this sort if keeps the immunity topped up like a booster shot but i think the jury is out on how true it is.

@MillieEpple

I think the shingles link is that one of the reasons we dont vaccinate in the uk is the children getting chickenpox exposes the adults to the virus again and this sort if keeps the immunity topped up like a booster shot but i think the jury is out on how true it is.

I read that as well.

Oh and incidentally after the Spanish flu pandemic, there was a rise in the incident of Parkinsons disease amongst the population. Just heard an epidemiologist wittering on, on the radio. So due to no-one knowing the long term side effects of this new disease this is another reason why the herd immunity theory of getting everyone to catch it is a no-go.

Chickenpox isn’t ‘contained’ at all though. Most children get it.

I think people are confusing herd immunity with immunity with chickenpox.

www.thelancet.com/journals/lancet/article/PIIS0140-67362031924-3/fulltext

Pretty much every disease was controlled in way this prior to vaccinations. Herd immunity isn't a set point though. Firstly we have other measures (eg isolation, hygiene), secondly immunity in the herd will fall after a while, leaving the population vulnerable to new outbreaks.

The Common Cold is in fact dozens of viruses that each give immunity for a few years
hence why there are still enough going round for people to catch two or three a year.

Flu (and the other coronaviruses) mutate readily - hence why there is flu season

Many viruses cause minor illness so go round without people fully realising

Serious diseases are either mass killers / disablers or vaccinated against or both

Diseases that kill too many people go extinct themselves

I've had chicken pox 4 times. Maybe 5. The last time was quite recent but a 20 year gap since my last chicken pox.

SciFi
I've had chicken pox 4 times. Maybe 5.
Wow, the doctors must find you fascinating as everybody else in the world only has it once with symptoms
www.cdc.gov/chickenpox/about/prevention-treatment.html

@ListeningQuietly I remember going to see the Doctor about it (I was 20) he literally pushed his chair away from me when he saw the spots!

He had records of previous pox dates on screen.

I only ever get it in patches now. The time in my 20s was under an arm. The time recently was just on my back. I caught it from my DD when it was going round the school.

It's definitely not shingles and I'm never unwell with it. I stay at home though (self isolating before that was a phrase!) the time in my 20s I had to phone loads of families as I'd been babysitting.

I was only unwell the first time. My friend don't believe me until I sent her the picture of the spots (she's a senior nurse)

Ive seen a child where i work with chicken pox in year R, then again in year 3.

Measles. When I was a child there was no vaccine so most kids had it very young. I had it at 5. Once you've had it you don't get it again, or it's very, very rare to do so.