Covid-19: New variant 'raises R number by up to 0.7'

https://www.bbc.co.uk/news/health-55507012

by mellosouls • 6 years ago

42 77 6 years ago

bbc.co.uk

yash_8141• 6 years ago

Is there any theory or data that more the R or transmission rate less deadly the virus is in itself?Because then this might be good news.We reach herd immunity sooner with less chaos.

rich_sasha2• 6 years ago

It is already bearing chaos in British hospitals, and it’s early days.

With 50k infections a day, say the true number is 100k, in 3 months only about 1.5% of the UK popularion get infected, not really significant for her immunity numbers.

mynegation• 6 years ago

Is that right? 100K daily infections give you 100,000 x 30 x 3 = 9,000,000 in three months which is 13% of 68M. Not anywhere close to herd immunity but not 1.5% either

baggy_trough• 6 years ago

You're off by an order of magnitude.

kolinko• 6 years ago

Well, it’s a week after x-mass so all countries see big increases because of family gatherings

sbinthree2• 6 years ago

I've read that the viral load is 10-20% higher on average, so if anything it's the opposite, but so far no one has gone on record saying it's more severe. It's more the compounding effects of higher viral load and easier transmission. Unfortunately, the UK hospital situation will probably get worse based on those two assumptions.

ComputerGuru• 6 years ago

Viral load is a poor metric. It is higher before major symptoms start (before it moves from UR to lungs), and so it goes down over time. You can be dying of COVID and test negative altogether if you’re fully past the initial stages (though you won’t be contagious, which is arguably the real point of the test). So a) a newer variant will definitely have a higher viral load on average just because people are more likely to be at an earlier stage in the infection cycle, especially if it is more transmissible, b) if a virus theoretically stays in the upper respiratory for the duration of the infection, it’ll have a higher average viral load while being less dangerous (in that sense, they are inversely correlated).

jsnell• 6 years ago

The increase in viral load is a bit more substantial than 10%... The study [0] shows a 10-100x increase for the median case.

[0] https://www.medrxiv.org/content/10.1101/2020.12.24.20248834v...

raverbashing• 6 years ago

No, not really. The letality of the new variant seems to be the same but of course, more infections will mean more causalities

u801e• 6 years ago

I don't think that herd immunity can be achieved without a vaccine. We never had herd immunity to smallpox, polio, measles, mumps, rubella, varicella, or any other virus until we had vaccines for those viral diseases.

azangru• 6 years ago

Is there any theory or data that more the R or transmission rate less deadly the virus is in itself?

There's a vague evolutionary argument that the less deadly for the host a parasite is the more widely it can spread and thus the more evolutionarily successful it will become. But there is no mechanism that guarantees the inverse — that an increase in infectiousness will be accompanied by a decrease in lethality. From the molecular biological perspective, the molecules responsible for viral spread and the molecules responsible for the damage that the virus does to its host (or that the host does to itself when attacking the virus) are likely to be quite different, so there is no reason for a change in one to be accompanied by a change in the other.

setr• 6 years ago

But there is no mechanism that guarantees the inverse — that improvements in infectiousness will be accompanied by a decrease in lethality.

I’m not clear; the argument effectively defines infectiousness as how-not-lethal the virus is. Thus, the virus cannot be made more infectious without decreasing lethality.

There is however an interim period, as evolutionary arguments are long-term arguments, where the virus can be both more infectious and more deadly, before settling into its stationary state.

The molecular perspective isn’t too useful against an evolutionary argument as well — evolution is always a sum-of-the-parts system. The question is simply: is the virus ultimately more capable of spreading? And at least in the extreme, an instantly killed host is unlikely to do an real spreading, no matter how trivially the virus could spread (had the host persisted). And in the other extreme, a completely non-lethal virus can survive and spread forever, especially in dense populations, especially if it doesn’t incapacitate the host significantly (acting as a simple parasite), allowing it to continue meeting new hosts.

Of course, a virus that doesn’t need the victim to be the host is a different story; eg malaria persists and spreads through mosquitos, so it could instantly kill humans and yet receive no evolutionary pressure against it.

x86_64Ubuntu• 6 years ago

The herd immunity thing is still a pipe dream. No one has mentioned or even hinted at it being less lethal so I'm not sure why that would even enter the discussion.

Trasmatta3• 6 years ago

Yeah, the only way we're getting to herd immunity without the current disaster becoming exponentially worse is with the vaccines.

numpad0• 6 years ago

Mortality is said to reduce because less severe virus keep the hosts more mobile and increase chances of transmission, outnumbering more severe variants.

For the COVID though, IIUC there’s 4-day asymptomatic phase where most of transmission occurs, followed by 2-week symptomatic phase, and it is thought to be unique. So it’s not clear if normal rules of thumbs apply to it.

tejohnso• 6 years ago

Further research is needed to understand why the variant is spreading so quickly. But early indications are that vaccines should be effective against it.

Pyramus3• 6 years ago

I will for the life of me not understand why (many) reputable media sources do not link the primary research. Make it a small link at the end of the article. That's it.

https://www.imperial.ac.uk/mrc-global-infectious-disease-ana...

the-dude• 6 years ago

Obviously, you are not a publisher.

They don't want you to leave their premises. That's why.

kossTKR3• 6 years ago

Interesting. I've thought about why journalism in general today never links to anything, sources or even mentions any competing media of any kind.

Often you think why don't they just mention the book, the theory, the article.

A pretty sad state of affairs and against everything that makes the "web" great.

oliwarner• 6 years ago

BBC doesn't make money from it's pageviews from it's main audience though.

erentz• 6 years ago

An interesting thread here on this topic. That 0.7 increase can have devastating impacts. Also worth noting this variant is now spreading in SoCal, CO, and most recently found in FL too. So the post holiday surge that’s already underway could get compounded by this variant.

https://mobile.twitter.com/dgurdasani1/status/13447745557185...

CydeWeys• 6 years ago

People have been saying since early 2020 that this winter was going to be the absolute worst of it (based on historical experience with e.g. the 1918 flu pandemic), and they were right. They didn't anticipate how quickly we'd develop a vaccine, but they also didn't anticipate such a more contagious variant. And the vaccine unfortunately won't roll out fast enough this winter to really put a damper on it.

I fear that by February most cities will be going through what we here in NYC faced last April.

kossTKR3• 6 years ago

I agree, but i also find it quite weird that the "seasonal angle" has been almost non existent, so why are people surprised?

Most regions of the world have been following the regular flu intensity almost to a T. Especially in northern Europe after a summer with almost open societies and no grave surges.

With this in mind we will peak when regular flu used to peak, ie. we are only now at the very start of some very bad months (for the latitudes with winter now).

Also while this new variant may be the culprit, the regular flu probably also mutates in a similar pattern - though it could be that this variant is a heavy factor, but for me we are still pretty much following the seasons.

dm3193• 6 years ago

Had a quick look at the figures for the UK today - it looks really bad, we've just overtaken the US on daily caserate at around 750 new daily cases / million. Germany were previously increasing fairly alarmingly in November, but seem to have been able to slow the increase down, if not get it heading down again. France had a large spike in November, got it under control in December, but are on the rise again (though under a new lockdown/curfew as of today).

The problem now in the UK is the winter pressures are at their worst, we haven't even seen the impact of Christmas relaxation yet, and we've just exceeded the peak number of covid inpatients seen in the first wave. We're going to start seeing hospitals closing to new admissions soon (diverting to other nearby hospitals) as they hit full capacity.

lumberingjack• 6 years ago

Meanwhile in the "hardest hit" county in Ohio. The county commissioner is explaining to everyone this morning why the official covid numbers don't actually matter don't make any sense. And that that little map they have is totally bogus.

selimthegrim• 6 years ago

Franklin? Cuyahoga?

ed25519FUUU2• 6 years ago

I’m interesting the research going into “excess death” statistics, which I think will be the only “true” death rate from the pandemic[1].

So how do we get this bigger picture? That’s where what researchers call “excess death” data come in. Simply put, excess deaths are the difference between the number of deaths that were expected to occur during a given time period and the number of deaths that actually occurred.

I suspect some deaths are being mis-attributed to C19 (for example that gunshot story). While other things are probably being undercounted.

1. https://www.cdc.gov/coronavirus/2019-ncov/cdcresponse/accomp...

choward2• 6 years ago

Excess deaths aren't entirely useful since they also include deaths caused by the covid mandates. Those deaths will also be occurring over the next several years which will make it more interesting.

mrfusion5• 6 years ago

Anyone else think this will never end? How many years will you stay home?

brundolf• 6 years ago

People are literally getting vaccinated as we speak.

mrfusion5• 6 years ago

https://www.cnbc.com/2020/11/16/fauci-why-still-need-masks-s...

Feels like another goal post being moved.

(FWIW I’d love to be wrong, so please share any optimism.)

oxfordmale5• 6 years ago

Pandemics like this last two years. It will be over in 2022. Even without vaccine herd immunity would set in at some point. The vaccine roll out is going to speed this up, although it will take until the summer before it starts having a major impact on the number of cases

mrfusion5• 6 years ago

Interesting. What makes you say two years?

spideymans• 6 years ago

Even without vaccine herd immunity would set in at some point.

Doesn't immunity only last a few months?

dm3193• 6 years ago

I understand that this is how it feels. But the natural history of pandemics is that they end.

mrfusion5• 6 years ago

This one will end but how do you fell about these kind of articles?

https://www.vice.com/en/article/k7q9x9/humans-living-in-age-...

williamstein• 6 years ago

HIV/AIDS is the other pandemic right now.

a-dub2• 6 years ago

yikes... if it still spreads like crazy in commerce/public space shutdown conditions, i wonder if this variant is more conducive to fomite spread.

i also wonder what can and should be done now to prepare and lighten the load on frontline nurses and medical staff. maybe it's time to train up and bring in an army of techs to mind the machines?

ed25519FUUU2• 6 years ago

I believe the vaccine is what “lightens the load” so to speak.

hedora2• 6 years ago

In the US, we decided not to train up more people to help. In fact, over 1,000,000 doctors have been laid off or stopped working during the pandemic.

The time to build up our response capacity was this summer. We spent trillions of dollars to buy time, but didn’t spend a comparably small amount of money to actually prepare for this winter.

In short, it’s too late. Current shortages of health care were completely predictable and avoidable.

choward2• 6 years ago

Exactly, there's two ways to make sure hospitals aren't overrun. Decrease the number of patients or increase capacity. For some reason everyone is only focused on the former.

a-dub2• 6 years ago

there is still more time now than there will be in a few weeks to take steps. they literally built hospitals in 10 days in china, i think we could relax some regs and allow health systems/med schools to train up a few thousand technicians.

this whole "oh welp we fucked up let's just let the healthcare system deal with it" attitude is terrible. there are steps that can be taken now.

nmca5• 6 years ago

Can anyone point to an explanation of how much the 60% Oxford vaccine will help things, both in the old case and in light of the new variant? I have approximately 0% intuition for how much a 60% vaccine helps.

oxfordmale5• 6 years ago

The Oxford vaccine might only be 60% effective preventing COVID infections, howver, it is much more effective in reducing hospitalisation and deaths. Contracting flu is a bummer, but a minor inconvenience when compared to dying.

nmca5• 6 years ago

Can you provide citations for this (first sentence)? My understanding is that there were no deaths in the treatment arm of the trial. But deaths are much rarer than infections so naively our uncertainty on this effect should be much larger than uncertainty about 60% infection rate reduction. Secondly, even if true, does this mean full restrictions until all are vaccinated?

jey• 6 years ago

The underlying question is how much of the population has to be immune for "herd immunity" to take effect. The pandemic will burn out once enough people (let's say X% of the population) are immune to the virus, and this is called "herd immunity".

Let's take the UK as our population. If a vaccine is 60% effective and we administer it to everyone in the UK, then about 60% of the UK's population will gain immunity to COVID. Another Y% of the population will have immunity to COVID already, even if the vaccine didn't work for them. Then the question is, is Y + 60 > X, thereby achieving herd immunity?

You can see that if a vaccine is 95% effective, it's more likely to be above the herd immunity threshold of X%. Current estimates for X are about 70%.

nmca5• 6 years ago

Ignoring herd immunity, there is also a reduction in mortality rate as older people are vaccinated. Do you have any sense which of the two effects dominates, and any citation for the 70% number? Thanks for the response :)

hedora2• 6 years ago

Oxford measured differently than the 90% mRNA vaccines. In particular, the 60% was based on testing for asymptomatic cases, and 90% was not. The three vaccines work on similar principles. I’ll assume they are all the same.

So, expect them to cut symptomatic cases by 90% among people that get the vaccine, and to add up to (60% * the percentage of people that get the vaccine) to the herd immunity progress bar.

The vaccines will likely cut total deaths by less than 90%, because vaccines tend to be less effective on more vulnerable people, and of course, less than 100% of the population will get it on time.

We could get lucky, and they could cut deaths of immunized people by more than 90%; no one knows yet. However the dosing screw up in the Oxford study inadvertently showed it is much less effective on old people.

The new variant speeds up the clock, which means more people will catch COVID before receiving the vaccine. It’s an exponential curve, so if the current R value is 1 (optimistic), and with new lockdowns and the new variant it’s 1.7 (taking the doomsday “add 0.7” from the headline), then cases will increase ~1.7x every two weeks. There are 18 two-week periods between now and fall, when Fauci says we’re likely to return to normal. 1.7^18 is ~14,000x.

There have been 83M confirmed cases globally according to Johns Hopkins, 83M * 14K >> the population of the earth, so the vaccine will be rounding error if the headline and Fauci’s warnings are correct. (It will allow frontline health workers to keep working, but that’s about it, and the hospitals will still be overrun).

If we assume the roll out takes 6 months, and the new variant increases R value by 0.3 (in range according to the article), then 1.3^12 = 23x. There’s some time lag while the new virus is mostly in the UK, and more stringent measures could reduce 1.3 by a little bit. In that scenario, the vaccine will still save many people.

I suspect the second scenario is more realistic.

dm3193• 6 years ago

It's thought to be much higher than this, I think we're expecting another paper soon that shows it more comparable to pfizer/moderna. But you have to be cautious with comparisons between the trials - the control arm was different, and the follow-up was different (Oxford were swabbing weekly).

The advantage of the Oxford vaccine is it can be stored at room temp. The Pfizer vaccine is largely being rolled out at large teaching hospitals - which means we can't get to the elderly and infirm, without risking exposure to them by bringing them up to the hospital. The Oxford vaccine would allow GP surgeries to give out the vaccine, as well as do home visits.

I'll admit that I don't know the maths behind whether a 60% reduction (which I think would multiply R rate by 0.4) will completely mitigate the increase in R by the new variant (multiply R by 1.74). It's all about a tipping point and getting the R to stay under 1, but as I pointed out above - it's difficult to compare studies using different methodologies.

nmca5• 6 years ago

Pfizer is storable at dry ice temp for ~months and regular vaccine fridge temp for 5 days [0] so whilst "large teaching hospitals" is currently accurate I don't think we're married to it.

[0] https://www.pfizer.com/news/hot-topics/covid_19_vaccine_u_s_...

kossTKR3• 6 years ago

What i don't understand is that after getting Covid, you are only immune for 8-20 weeks - a few public persons have already contracted Covid twice now illustrating this.

With this new variant, and the fact that we need some pretty incredible amount of people immune at once, maybe say 80%, wouldn't this mean that we need to be vaccinated 4-5 times a year?

How is this feasible, even for the richest countries?

dehrmann3• 6 years ago

you are only immune for 8-20 weeks

Citation needed. Last I read, it's likely much longer, and the few people are outliers.

jibcage• 6 years ago

Are there any indications yet that this makes masks less effective for controlling the spread indoors? And if so, by how much?

“Raises R number” could mean any number of things - is it more infectious through touch, by breathing it in, or when viral particles reach your eyes?

Pyramus3• 6 years ago

Wikipedia has a good summary of what we know: "there were insufficient data to reach any conclusion on underlying mechanism of increased transmissibility (e.g. increased viral load, tissue distribution of virus replication, serial interval etc.)" [1]

is it more infectious through touch, by breathing it in, or when viral particles reach your eyes?

I think a better mental model of transmissibility is to think of what concentration of viral particles is needed to trigger the reproduction. It seems that there is some early indication that the new variant binds more easily to human cells (N501Y mutation) so a lower concentration of particles is needed, and also infected hosts distribute more particles (higher viral load).

An actual expert on viral transmission please chime in.

[1] https://en.wikipedia.org/wiki/Variant_of_Concern_202012/01#T...

hannob• 6 years ago

I think this is the one covid fact far too many people haven't internalized yet.

This changes everything. It means in essence for everything we do to slow down covid from spreading, we need to add additional measures on top of that to achieve the same effect.

rurban• 6 years ago

0.4 - 0.7. The original R increase was published as 0.4, and so far I believe the lower number.

The critical insight is not R being a bit higher, R could be easily brought down by 2.5 by policy measures, but the age group of <20 being dominant there. That's why R is a bit higher.

thinkingemote• 6 years ago

The range is from 0.4 to 0.7

The research found a spread, not a new stable level. The average was towards the lower end than the higher.

Covid-19: New variant 'raises R number by up to 0.7'

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