Coronavirus
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The Mayor of London. But unfortunately not official.
The situation is broadly the same now, as it ws in the beginning apart from the advent of accines the same vulnerable groups are exposed.
Other scientists said it was increasingly clear that the virus would be here for the long term and that the government needed to change strategy. “Having 20 million people vaccinated is likely to help reduce numbers of cases but we must not forget that this is a highly transmissible virus and if we do not continue with social measures, it will soon whip round communities again and cause havoc,” said Liam Smeeth, professor of clinical epidemiology at the London School of Hygiene & Tropical Medicine.
UK supermarkets to enforce mask-wearing on customers. What to expect as where i stay it has been policy for several months and technology has been introduced to enforce it.
Automated swing-gates have been installed at supermarket such as Tesco entrances with cameras and thermometers. It guages if you have a high temperature by raising your wrist to it and the camera recognises if you have a mask in place before they swing open.
The recent shopping mall i mentioned failed to install such technology and it is where what seems now to be an isolated case was found.
Useful reminder that everybody not living Oop North is well off living in leafy suburbs surrounded by golf courses. There’s deprivation in the South too. In fact everywhere. This article suggests that this is why the new variant started there:
29 post-vaccination deaths in Norway.
I had the Pfizer jab on Wednesday and I am still alive.
Before the Covidiots and the anti-vaxxers jump to their prejudged conclusion wait for the facts to emerge:
ALB, i thought you said you were going to postpone receiving the vaccine until you were sure it had no unwelcomed side-effects.
No word here about the vaccine roll-out.
But it does seem like the vaccine is the type that will require boosters each year or so. Guaranteed income for the pharmaceutical industry despite the pledge that they will be non-profit…only for this years initial shot.
It seems the Chinese vaccine being sent to the poorer nations works only 50% of cases …that seems a very low figure to me
Although they say it is still effective against the mutations, will it be in the future.
Is there a statisticians in the house? What does it mean to say that a vaccine is 50 (or whatever) percent effective? Does it mean that it “works in only 50% of cases”?
Does it means that 50 of those who have the vaccine jab will get the virus? Or that anyone who has the jab is only 50% protected (ie has a 50/50 chance of getting it)? Or are these the same?
According to this,
“When we talk ‘vaccine effectiveness,’ what we’re talking about is, ‘How effective was the vaccine at preventing actual disease?’ ” explains scientist L.J. Tan, chief strategist of the nonprofit Immunization Action Coalition.
In other words, Tan says, “If you vaccinate 100 people, 50 people will not get disease.””
But does that mean that 50 of those vaccinated will get the disease or just that they could get it? And how do you know which group of 50 you fall into?
Still, it seems that you increase your chances of not getting it even if the effectiveness is 50% (or less, for that matter).
But, as I said, is there a statistician in the house?
Does it means that 50 of those who have the vaccine jab will get the virus? Or that anyone who has the jab is only 50% protected (ie has a 50/50 chance of getting it)? Or are these the same?
It means at least a 50% reduction in cases of COVID-19 in those who are vaccinated. A bit of a lottery. 🙁
I am not a statistician, but use theoretical probabilities in efficacy of social assistance.
There is a theoretical probability (1 in 2 chances expressed as a percentile is 50%). This is theoretically probable with very large number with 2 possible outcomes. Mass populations, or numbers can arrive at an efficacy of 50:50
However in experimental probability of efficacy, it looks at the actual n or numbers in the control group. I think it is way too early in the roll out and trials to get a theoretical prob- sorry I am use to using p(x) values… so forgive me.
If efficacy stands at 50% in the observable trials- then 50% it is at the moment, could adjust over time.
Control group, sample sizes, are usually equate to the populations and its numbers to capture it, but the error margins will always occur.
This may help or complicate further- but worth a trying challenge!Vaccination efficacy
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50% vaccination efficacy = risk of infection after vaccination = 50%
- = 50 cases after vaccination for every 100 before (i.e. no inoculation)
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70% vaccination efficacy = risk of infection after vaccination = 30%
- = 30 cases after vaccination for every 100 before (i.e. no inoculation)
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90% vaccination efficacy = risk of infection after vaccination = 10%
- = 10 cases after vaccination for every 100 before (i.e. no inoculation)
Immunity is not guaranteed. Herd immunity is a way off.
Allied states point the finger at enemy states given the slightest excuse, the slightest evidence of failure or inferiority, remember.
Thanks. That seems clear. So, if there is 70 percent efficacy that means there will be a reduction by that amount among those vaccinated. The trouble is, from an inoculated individual’s point of view, that you can’t know whether you are going to be in that 70 percent who won’t get it. A lottery, as you say, but presumably the chances of not getting it are more than if you don’t get vaccinated at all.
If you get to the stage of 100% inoculation, then the 70% of the population who are vaccinated and have immunity is usually enough to stop widespread community transmission. However the two vaccines currently being administered have different efficacies, one around the 90-95% and one around 70%. The level of cover will then depend upon the proportion of each given and also to which age groups they are given to (younger people and care staff would be more likely to transmit than older people in care homes because of their social pattern). This all also depends upon whether or not the immunity given by the jab also stops transmission.
The immunity from infection that the vaccine provides is not like a force field to the virus, the virus does enter the body as it usually would, however the immune system kills it off before it can establish itself. It may be that during this process of killing it off the virus is still infectious. Even if this was the case it is likely that the amount of time an infected person who has had the virus is infectious to others would be much reduced.
Taking this further from the original stage three trial of the Oxford vaccine, even of those who tested positive after the vaccine, non progressed to the level of needing hospital treatment and none died. The implication of this is that the vaccine boosts the immune system enough to deal with the infection eventually, although the virus does gain some foothold
Going back to ALBs point about the 50% effectiveness, this comes from the trials and relates to the difference between the vaccinated group and the non vaccinated group. You create two matched cohorts (matched for age, health conditions, etc.) if you had say 10,000 in each group you would measure the infection rate across both groups you would measure the infection rate from the control group who were given a placebo and the vaccinated group. In the case of a 50% effective vaccine, half as many in the second group would have test positive for the virus over a specified time than in the control group. It does not therefore measure the other effects of suppressing the virus to a manageable condition in the vaccinated subjects who were infected, but that is also an important factor.
I was amazed to get asked last week to make a jab appointment for this week. I’m having it on Wednesday. I’m only just 70. Also it’s at a local GP practice, though not the one I’m registered with.
Could this mean that a lot of older or vulnerable people have decided not to have it and they’ve moved down early to the people in group 4?
I was also surprised by a stat that said nearly half a million people have had their second jabs. How can this be? Hardly a month has passed since they started the rollout, let alone 12 weeks.
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