Super spreader theory or myth

[JellyYuck]

Anecdotally, do you believe that there are super spreaders? IME of recent weeks it's not a given that you get infected even after prolonged close contact but there are cluster breakouts such as in school or some families where everyone gets infected very quickly.

Is it possible that it's super spreaders driving the current surge?

I haven't seen anything that suggests enough is known about the omicron variant to be sure.

You might also be interested in this, from earlier in the pandemic, about the importance of the K number

www.theguardian.com/world/2020/jun/01/k-number-what-is-coronavirus-metric-crucial-lockdown-eases

Wasn't there a super spreader event really early on? Couple from China flew to Singapore, went to church, then loads of people came down with it. Can't remember the details!

It's quite likely, btw, that one of the features on omicron is a higher secondary attack rate (ie if you expose say 10 people to 1 infectious person, how many catch it) which means more people are going to get it, regardless of the role of superspreaders

I thought there were well documented cases even before Omicron.
Some people have also been measured as exhaling far more virus than others.

So though fomite transmission has been discredited as a major driver there have been superspreader events. Wasn't Oslo one just recently?

Yes there was a church one early on.

It's strange that many cases don't pass on within a household. I know of several families where on child had covid and no other household member caught it. I know much fewer families where it spread round the family. We've had several covid cases in Ds'a class during the pandemic and no outbreaks but 10 dc got infected last week alone. How does any of this make sense?

I think the thing is it probably won't make a lot of sense to us mere mortals. I don't have any basic knowledge of this sort of thing, I'm not sure I even did that well at science at school. So much of the last two years has relied on us making our own risk assessments (and being berated by others if their risk assessment of something is different from our own) but actually most of us don't really "get it" enough.

What has asking what we believe got to do with actual scientific facts? They might not be fully understood yet but they are still scientific facts. What we believe is irrelevant.

I didn't mean that to sound quite so curt, by the way.

@JellyYuck

It's strange that many cases don't pass on within a household. I know of several families where on child had covid and no other household member caught it. I know much fewer families where it spread round the family. We've had several covid cases in Ds'a class during the pandemic and no outbreaks but 10 dc got infected last week alone. How does any of this make sense?

It's not strange. That's what viruses do to survive. They are not consistent.

In our school, barely any cases over the two years now suddenly it’s ripped through everyone, hundred gone down in space of a few days on busy week of the year

Obese older people spread the virus more efficiently

www.pnas.org/content/118/8/e2021830118

They are the super spreaders

Same here @Cocopogo

I agree, I think there’s more natural immunity than previously thought, but not sure how you test that theory! Either immunity from a previous simile infection or having had asymptomatic Covid.

I’ve had Covid and no other family members caught it, DD has been around loads of positive cases (prior to them testing positive) and hasn’t caught it. Neither has my DS. Every friend of his has had it except him - they all were on a day out and he’s the only one who didn’t catch it!

So something doesn’t ring true.

The R number is made up from three things:

a) how long an infected person is infectious for (and whether infectious before symptoms start - ie whether they can be wandering round infecting people before they know they've even got it - something which can happen for about 48 hours with covid)

b) the secondary attack rate - how many of the people an infectious person comes into contact with who will catch it (might be higher with omicron)

c) how many people the infectious person comes into contact with, especially in circumstances favourable for transmission.

The first two are characteristics of the virus/variant itself, and we can do sod all about that. The third is the one that can be changed, and it's why measures are all based on reducing the number of people you come into contact with (limiting non-essential activities and distancing) preventing infectious and likely-to-be-infectious people from coming into contact with others at all (quarantine and isolation) and making the circumstances of contact which does occur less favourable (masks, ventilation)

It is quite likely that omicron has a much higher secondary attack rate than earlier variants, thus increasing the R number.

Plus it seems to evade previous immunity rather better, so more people are vulnerable (as the proportion of the population is immune, the effective R drops, because the secondary attack rate goes down as not all contacts will be susceptible, if immunity can be evaded then it goes back up a bit)

@hamstersarse

Obese older people spread the virus more efficiently

www.pnas.org/content/118/8/e2021830118

They are the super spreaders

I'm not at all sure you read that correctly, or completely!

It is weird!

I know several older people who tested positive with PCR tests but had absolutely no symptoms, then I know someone else who is in his forties and fit and almost died. I don't get how there is so much variation in how people react.

In the early days of Covid, a guy at a college near me managed to infect over 100 people. They traced the infection back to the canteen where I guess everyone was maskless and talking.