Stgermainparis

Thanks. I did make a preemptive appointment actually. Was wondering if pharmacy could turn away if FDA and CDC have approved. Not sure why they would though. Sounds like they will honor the appointment. It’s concerning to me that so few people are interested in vaccinating their children.

nk15

So, approximately 1 in 10k is the breakthrough infection rate.

ajGoes

In the first few weeks after vaccination, yes. It will presumably go up over time, but it's encouraging that it's starting so low.

GUWonder

Reported breakthrough infections rates are going to be changing for quite some time during this year, although they should become much more static and even more telling in ways if (and/or after) a very high proportion of the public ends up having completed a highly effective vaccination regimen.

GadgetFreak

Yes, but don't forget most of those millions of people were never exposed to the virus so wouldn't have been infected even if they hadn't been vaccinated. The clinical trials showed the vaccines to be 95% to 97% or so effective by doing this type of analysis in comparison to people that weren't vaccinated as a control group. A control group is needed for a meaningful number.

nk15

Good point, I think many vaccinated people are also likely to be more careful as well, compared to unvaccinated ones (which may sound paradoxical, but likely true for at least many of them).

In other breaking news, Covid spreads through the air, CDC admits....

Airborne Coronavirus Is a Threat, the C.D.C. Acknowledges (msn.com)

Loren Pechtel

In the US the issue now is more a matter of the availability of arms rather than shots. If someone isn't vaccinated it probably means they don't consider the virus a threat to them. Thus why would they be all that cautious about it? Thus I don't find this remotely paradoxical.

Duh! It's been obvious for a while.

GadgetFreak

Yes, that too. That’s why the clinical trials used a placebo injection for the unvaccinated controls so that the vaccinated people wouldn’t behave differently than the unvaccinated ones.

Although as an aside, there is a conversation I had with a psychiatry professor years ago. We were at a bar during the evening of a class and I asked him if he wasn’t concerned about a placebo effect from some class of drugs. He said, “I’m a psychiatrist, I’ll take all the placebo effect I can get. It’s not like I’m an oncologist and if my patients have a placebo effect they might still die. If my patients feel better, they are better”.

PanAmWT

A real world test of the Sinovac vaccine against the P1 variant:
https://www.wsj.com/articles/brazili...0392401?page=1

The article may be behind paywall. I am copying a few paragraphs below

A Small Brazilian Town Is Beating Covid-19 Through a Unique Experiment WSJ (5/7/21)

SERRANA, Brazil—This town of 45,000 people in southeastern Brazil has been at the center of a unique experiment for the past three months: vaccinate nearly every adult against Covid-19 and see what happens.

In recent weeks, after most of the adults here got their second dose, Covid-19 cases and deaths plunged and life has started to return to normal as the pandemic continues to rage across Brazil.

In the heart of Serrana, children squealed with laughter as they chased each other across the main square, while groups of friends—many unmasked —stopped to chat and bask in the afternoon sun.

“We feel free,” said Homero Cavalheri, 68 years old, a retired architect who said he no longer spends his afternoons cooped up at home. He was strolling with his wife, Irene, and their 1-year-old grandson. “Everything is new to him,” said Mr. Cavalheri, clutching the boy. “He keeps pointing at all the trees and the birds.”

The experiment in Serrana, a town in Brazil’s sugar-cane-producing savanna, provides hope for countries around the world still battling with coronavirus outbreaks that mass vaccination works. It also offers new evidence of the efficacy of Sinovac’s Covid-19 vaccine, which is being rolled out in dozens of developing nations from Egypt to the Philippines.

All of Serrana’s adults were offered CoronaVac between February and April as part of the experiment, known as Project S. It is the first mass trial of its kind in which an entire town is vaccinated for Covid-19 before the rest of the country.

Not everyone in the town was eligible, including minors under 18, adult women who are pregnant or nursing, and others with serious health problems. Of the roughly 27,700 eligible adults, 27,150, or 98%, were vaccinated, according to town officials.

Town officials and residents said they are thrilled with the results so far. Infections are down 75% from a March peak in Serrana, while there have been no deaths from Covid-19 among the people who were fully vaccinated, suggesting CoronaVac is also effective against the aggressive P.1 variant sweeping the region.

“The numbers speak for themselves,” said Serrana’s mayor, Léo Capitelli. “It worked!”

In the waiting room of the town’s intensive-care unit, the effects of CoronaVac are already visible. “Only three weeks ago, this was so full, people had to stand,” said Lucia Elaine Caldano, the unit’s administrator, pointing to rows of empty chairs. In the past three weeks, only one person has been put on a ventilator—a woman who had refused to take the vaccine.

invisible

Posting here this reply in another thread, have couple of follow up questions below:

Based on observation it seems (please correct me if wrong) that number of cases in US is in range of 40k, while deaths is continuing to decline.

​​​​​​My question #1 - assuming that three vaccines in US cut not only serious complications/death, but transmission as well, as CDC indicated - with the current >40% fully vaccinated adults in US, what the vaccination rate needs to reach to significantly cut cases and deaths (like less than 10k cases daily and less than 100 dead daily)?

Question #2 - how it can be explained that UK cut cases/deaths significantly compared to US while having less numbers for fully vaccinated population and using slightly less effective vaccines?

DaveS

I can offer my own view on your second question at least. Most of the protection from the vaccines comes from the first shot. Only considering fully vaccinated people (with 2 shots) is not useful in comparisons. There has even been some debate on whether it is worth bothering with the second shot for much of the population. The UK was very early with its first jabs. The vaccines used in the UK are proving to be extremely effective in the real world. Saying they are not the most effective compared to others is not born out by the experience here.

corporate-wage-slave

Before answering these very relevant questions, there is one context point that needs to get across. On a big population basis, it's the over 50s that get really bad outcomes with Covid, a lot of transmission is from other people in the same household, and that it's meet-ups between households that transmit - friends, family, social groups such as church meetings and weddings. Randoms in the supermarket? Not so much. So you get a huge bang for your buck if you can (a) vaccinate those over 50 AND (b) the percentage coverage of that particular cohort is high, ideally well over 90% - in the UK just under 97% of those 50 plus have now had at least one vaccine. Why is this important? Because people like to spend time with people their own age, and so does the virus.

1) So the USA 40% adult rate for completed vaccines - compared to 34% in the UK - is great news but vaccinating 30 year olds isn't your current focus. It will be by the autumn, so it's still good overall, but not right now. In the UK we originally thought we could just about get 85% coverage, taking into account vaccine hesitancy and male laziness to their own health in the UK, so getting 97% coverage in the over 50s made a game changing difference. The USA has about 55% adult coverage for 1 dose (UK is 67%) so if you're going the blanket route - which to my mind is a slower and more economically damaging approach - you need to get that from 55% to about 70%, and that's a figure you will have heard from the White House, and it's not a coincidence. So late June is the short answer to your question, but I think from early June will start to be good for the USA, which is about to fall below 200 cases per 100k per 14 days - I think some great data is coming up.

2) The UK did well due to targetting the older population first, as shown above. If we look at real world data AZ is as effective as Pfizer - the differences between vaccine X versus Y come from trials which were done somewhat differently to each other. Any minor differences between vaccines (and I doubt this exists at the T cell level) is easily drowned out by getting the right people vaccinated sooner with at least one dose. That single dose alone is good enough for the current context, and we are so incredibly fortunate to have such powerful vaccines available to us. Longer term we need everyone vaccinated, not just the 50+ year olds, and perhaps boosters too, so at least the USA is going in the right direction for the autumn of 2021.

The UK also does a lot more testing than the USA, proportionately, and is still in Lockdown until next Monday, at least in main impact terms.

8420PR

I think the simple answer is the reduced social contacts in UK (also called lockdown), compared to the US. You can either reduce COVID cases through vaccination or reduced social contacts, and the UK has done both - which has proved very effective.

Source: https://ourworldindata.org/covid-google-mobility-trends

invisible

Thanks for answering. Let’s see how prognosis will play with the reality in 1-2 months.

BTW, latest figures show that in US, in the population of >= 65 y/o 84% got single doze and 72% is fully vaccinated.
https://covid.cdc.gov/covid-data-tracker/#vaccinations

I don’t know how much more effort will it require to get there numbers to 90% or even if it is possible at all. There is a saying in IT industry that it take 90% of effort to have 90% of a development done and remaining 10% also takes 90%.

In terms of tests - what are statistical relationships between positivity rate and number of tests? In US number of tests are declining but positively rate declines as well, currently at 4%. At what point you stop administering more tests?

ryman554

Mathematically, you know full well the relationship between positivity and # of tests, since (positivity = positive tests / # of tests.) As tests go down, positivity goes up. However, to a first approximation, when you are testing large # of people and have a low-ish rate, the rate of positive tests seems to go down at roughly the same rate as all tests, which, in the real-world, means that positivity is invariant to small changes in the # of tests, over a short range. Over sudden changes in testing, you'll see the mathematical definition, above. Barring that, importantly, changes in positivity rate seem to track (not match!) the infection rate well. So, changes in positivity are a great indicator -- much better in the short term, actually -- of changing infection rates than a total number of cases.

Test positivity is down in the lower 3.x%'s. Not great, but finally respectable. I'd rather have it below 2%.

Why do you say the number of test are declining? I see the test count as virtually flat since the end of the winter surge (mid February or so) I suppose one could look at the last couple of weeks and identify a very small negative slope, but in the grand scheme of things, test count is flat. source