Coronavirus

[Danzilla31]

No one yet knows the answer. But scientists are actively looking now.

Vaccines first became available in December, but only to front-line health care workers. They became more widely available in March and April. The people in the earliest clinical trials were vaccinated as early as last August. So, we are just beginning to have some 1-year-later-data about how long immunity might last. Stay tuned.

Okay great I'll be watching and thank you!

 

[Mr._Clark]

The rapid spread of the delta variant in Florida is somewhat disconcerting because the vaccination rate in Florida is only slightly less than U.S. average (49.7% of the U.S. is fully vaccinated, whereas 48.5% of the population in Florida is fully vaccinated). 50% vaccination rate is clearly not enough to prevent a significant increase in cases.

Perhaps it's partly due to the vaccines being less effective with regards to transmitting the virus, despite being effective with regards to preventing serious illness.

>>>The Pfizer Inc (PFE.N)/BioNTech vaccine, one of the most effective against COVID-19 so far, appeared only 41% effective at halting symptomatic infections in Israel over the past month as the Delta variant spread, according to Israeli government data. Israeli experts said this information requires more analysis before conclusions can be drawn.

"Protection for the individual is very strong; protection for infecting others is significantly lower," Davidovitch said.<<<

How the Delta variant upends assumptions about the coronavirus

The Delta variant is the fastest, fittest and most formidable version of the coronavirus that causes COVID-19 the world has encountered, and it is upending assumptions about the disease even as nations loosen restrictions and open their economies, according to virologists and epidemiologists.

www.reuters.com

 

[TLS Guy]

The Pfizer vaccine has been approved in Canada and in the US since May for children aged 12 and over. I assume the UK authorities are keeping an eye on our experience to guide them with regard to approval for that age group in the UK? Is the general populace completely ignoring what is happening elsewhere?

As I've learned recently - and I'm sure you already knew - side effects from vaccines manifest relatively quickly. There should be plenty of data available to support vaccinating British kids. I haven't seen any reports of problems with this vaccine in this age group. There wouldn't be time to get them fully vaccinated before starting school, but one dose would be better than no dose.

That is true, but the UK have been doing their own trials, and there seems to be concern of the number of myocarditis cases. However catching Covid causes more cases. They do seem to be dragging their feet in this. However, there does seem to be a high level of opposition to vaccinating children in the UK for some reason.
Part of it is that the Astrazeneca vaccine has been the foundation of the vaccination program there, but it is no longer approved for females under 40 because of clotting problems.

 

[TLS Guy]

The rapid spread of the delta variant in Florida is somewhat disconcerting because the vaccination rate in Florida is only slightly less than U.S. average (49.7% of the U.S. is fully vaccinated, whereas 48.5% of the population in Florida is fully vaccinated). 50% vaccination rate is clearly not enough to prevent a significant increase in cases.

Perhaps it's partly due to the vaccines being less effective with regards to transmitting the virus, despite being effective with regards to preventing serious illness.

>>>The Pfizer Inc (PFE.N)/BioNTech vaccine, one of the most effective against COVID-19 so far, appeared only 41% effective at halting symptomatic infections in Israel over the past month as the Delta variant spread, according to Israeli government data. Israeli experts said this information requires more analysis before conclusions can be drawn.

"Protection for the individual is very strong; protection for infecting others is significantly lower," Davidovitch said.<<<

How the Delta variant upends assumptions about the coronavirus

The Delta variant is the fastest, fittest and most formidable version of the coronavirus that causes COVID-19 the world has encountered, and it is upending assumptions about the disease even as nations loosen restrictions and open their economies, according to virologists and epidemiologists.

www.reuters.com

The vaccines will be less effective in preventing transmission by vaccinated people, as the disease can now be caused by far less of a viral load. So the threshold for viral transmission is now a lower number. That is really a matter of simple math.

I should stress for the record that the Delta variant of Covid-19 is the most infectious airborne respiratory infection the world has seen to date, and by a wide margin.
So everyone needs to mask up in areas of high community transmission. I would define that as a testing positivity rate of 5% or greater. In Minnesota we are 2.5% right now, but rising quite quickly. I would suggest you all follow the data from your state health departments.

The UK infections rate dropped again today, that is now 7 days in a row. So that gives some hope. Deaths and hospitalizations are riding, but they are lagging indicators, especially deaths. The UK recorded 107 deaths in the last 24 hour period. They were at zero deaths for a while before this fourth wave.

 

[Swerd]

I should stress for the record that the Delta variant of Covid-19 is the most infectious airborne respiratory infection the world has seen to date, and by a wide margin.
So everyone needs to mask up in areas of high community transmission.

Agreed about the need for wearing masks by people in those areas with higher Covid-19 rates.

The Delta variant of SARS-CoV-2 is quite a lot more infectious than the original virus strain (wild type) from December 2019, or the Alpha variant. But it's infectiousness is still less than that of measles, chicken pox, mumps, or rubella. I found this table on the Wikipedia page on Herd Immunity. (See the link to find the references.)

EDIT: See post #5552 for a revised table that shows the Delta variant is more infectious than previously thought.

The table clearly shows how much more infectious corona virus has become over a little more than a year. There is no question that the virus is evolving into more infectious forms. We don't know if Delta will be surpassed by other yet-to-be noticed variants in the future.

R0 (R zero) is the average number of new infections caused by each case. HIT is the estimated herd immunity threshold. R0 functions as a measure of contagiousness, so low R0 values are associated with lower HITs, and higher R0s result in higher HITs.

 

[GO-NAD!]

Agreed about the need for wearing masks by people in those areas with higher Covid-19 rates.

The Delta variant of SARS-CoV-2 is quite a lot more infectious than the original virus strain (wild type) from December 2019, or the Alpha variant. But it's infectiousness is still less than that of measles, chicken pox, mumps, or rubella. I found this table on the Wikipedia page on Herd Immunity. (See the link to find the references.)

The table clearly shows how much more infectious corona virus has become over a little more than a year. There is no question that the virus is evolving into more infectious forms. We don't know if Delta will be surpassed by other yet-to-be noticed variants in the future.

R0 (R zero) is the average number of new infections caused by each case. HIT is the estimated herd immunity threshold. R0 functions as a measure of contagiousness, so low R0 values are associated with lower HITs, and higher R0s result in higher HITs.
View attachment 49478

I'm curious as to how they calculate the R0 stats. I would think that the number would vary in place and time with different population densities, demographics and public health protocols. So, with the other factors being "fixed" could the R0 for the Delta variant be partially influenced by the relaxing of public health protocols as 3rd wave cases diminished?

 

[Swerd]

I'm curious as to how they calculate the R0 stats. I would think that the number would vary in place and time with different population densities, demographics and public health protocols.

Estimating R0 is an ongoing effort in a constantly changing epidemic. It's not a simple calculation. Welcome to Epidemiology 101.

Here's a taste as to why (quoted from the Wiki link in my previous post):

The critical value, or threshold, in a given population, is the point where the disease reaches an endemic steady state, which means that the infection level is neither growing nor declining exponentially. This threshold can be calculated from the effective reproduction number Re, which is obtained by taking the product of the basic reproduction number R0, the average number of new infections caused by each case in an entirely susceptible population that is homogeneous, or well-mixed, meaning each individual is equally likely to come into contact with any other susceptible individual in the population,[11][32][45]

For further insight (or confusion) read more: https://en.wikipedia.org/wiki/Basic_reproduction_number

So, with the other factors being "fixed" could the R0 for the Delta variant be partially influenced by the relaxing of public health protocols as 3rd wave cases diminished?

A good question, but I don't know the answer.

 

[GO-NAD!]

A good question, but I don't know the answer.

You disappointment me.

 

[Mr._Clark]

You disappointment me.

If you're in the mood for more disappointment, I present the following article in Quanta magazine, which further muddies the math modeling due to the generational interval, which makes it difficult to know how to interpret the observed data for purposes of calculating R0:

>>>To bridge the gap between what’s observable — the rate at which the epidemic is growing or shrinking, or what Dushoff calls its “speed” — and the desired value R0, or “strength,” another important quantity is needed. That’s the generation interval: the amount of time between when one person is infected and when they infect the next person. (Since that value can vary greatly, researchers might represent the generation interval as a single number, like the mean, or as a distribution.)

“There’s often a conflation,” said Joshua Weitz, a biologist at the Georgia Institute of Technology, in thinking “a faster growth rate must mean a higher R0.” But that growth rate really needs to be viewed through the lens of generation intervals, and how quickly one infection leads to another.

Consider a situation in which one initial case of a disease is followed, three weeks later, by the appearance of eight new cases. If the disease has a generation interval of one week, then that initial case would have led to two new cases after the first week, four the next, then eight. Each infection would have produced two others, for an R0 of 2. But if the disease instead has a generation interval of three weeks, then the first case directly produced the eight new ones, for an R0 of 8.<<<

Chasing the Elusive Numbers That Define Epidemics

Most modeling efforts during the COVID-19 pandemic have sought to address urgent practical concerns. But some groups aim to bolster the theoretical underpinnings of that work instead.

www.quantamagazine.org

 

[Mr._Clark]

The following paragraph from the Quanta article made me wonder about other aspects of asymptomatic transmission:

>>>This work has led Weitz and others to reinterpret some aspects of the disease’s propagation. Over the summer, for instance, “there was a narrative that cases were spreading in young people, and that their [irresponsible] behavior was driving that spread,” Weitz said. But behavioral factors alone might not be to blame: If younger people were biologically more likely to transmit the virus asymptomatically, they might have had an outsize impact on the rate of spread, simply because asymptomatic transmission has a longer generation interval.<<<

It seems to me that symptomatic people may be more transmissible compared to asymptomatic people than the statistics suggest. For example, if a typical infected person works with the same 10 coworkers every day and goes home to the same 3.2 carbon-based life firms (AKA family members) every day, most of these people may already be infected by the time the person becomes symptomatic and stays home from work. This would make it appear as if the person was more likely to spread the virus while asymptomatic, but this would only be true under these facts, not in general.

Simplifying, if the infected person must be in close proximity to another person for 10 hours while asymptomatic to transfer the virus, but only 1 hour is required once the person becomes symptomatic, in the example above all of the person's coworkers and family members would already be infected before the person became symptomatic.

Determining the infectiousness of asymptomatic vs symptomatic people would require a way to eliminate the effects of other variables, but I suspect most news reports touching on the topic are not based on studies that do this. If someone else has better information, please feel free to correct me concerning my suspicions (I don't have a horse in this race, it's just a matter of curiosity).

 

[Mr._Clark]

I ran across this paper about a vaccinated miners in French Guiana being infected by the gamma variant. The results seem odd given that the vaccine antibodies seem to be effective against the Gamma variant. Perhaps there's some other factor at play that the researchers were unable to identify.

>>>The attack rate was 15/25 (60.0%) in fully vaccinated miners, 6/15 (40.0%) in those partially vaccinated or with a history of COVID-19, and 3/4 (75%) in those not vaccinated. Attack rate was 0/6 among persons with a previous history of COVID-19 versus 63.2% among those with no previous history (Table). No other factors were found to be associated with the risk for infection. . . . Such a low vaccine efficiency against infection by the Gamma variant was not expected because in vitro studies have shown a similar reduction of neutralization for Beta or Gamma variants by BNT162b2-elicited antibodies (5) and a conserved CD4+ T-cell response against spike proteins from the Beta variant (6). . . . Given the surprisingly high attack rate, we hypothesized potential dysfunctions of conservation or administration of vaccines, but the absence of traceable cold-chain interruption and the use of different batches seemed to refute this hypothesis. The relative isolation of the mining site and careful contact tracing suggested limited numbers of viral introductions inside this community. The low Ct of positive PCR for SARS-CoV-2 despite prior vaccination suggested that a complete vaccination scheme with BNT162b2 vaccine was not sufficient to prevent symptomatic SARS-CoV-2 infection and its transmission in this context of communal life without masks.<<<

Breakthrough Infections of SARS-CoV-2 Gamma Variant in Fully Vaccinated Gold Miners, French Guiana, 2021

Breakthrough Infections of SARS-CoV-2 Gamma Variant

wwwnc.cdc.gov

 

[Swerd]

The Delta variant of SARS-CoV-2 is quite a lot more infectious than the original virus strain (wild type) from December 2019, or the Alpha variant. But it's infectiousness is still less than that of measles, chicken pox, mumps, or rubella. I found this table on the Wikipedia page on Herd Immunity. (See the link to find the references.)

I recently posted (post #5545) a table of various virus diseases that compares the R zero values of three different strains of corona viruses. It was just revised to show a bigger R zero value for the Delta strain. Delta is now thought to be more infectious than rubella and nearly as infectious as chickenpox and mumps. See the revised table below.

The original corona virus strain (wild type in the table) has an R zero estimated at 2.9 – enough to require that 65% of the population be immunized to achieve herd immunity. Delta, with an R zero in the range of 5-9.5, now requires immunizing 80-89% of the population before we can hope for herd immunity. Here is the link:

Herd immunity - Wikipedia

en.wikipedia.org

Because there are enough morons in this nation who refuse vaccination, we now have a more infectious form of Covid-19 endangering us all. Even worse are the politicians (and other leaders), who publicly urge others to refuse vaccination, while they hide their own secret vaccinations.

 

[mtrycrafts]

...

Because there are enough morons in this nation who refuse vaccination, we now have a more infectious form of Covid-19 endangering us all. Even worse are the politicians (and other leaders), who publicly urge others to refuse vaccination, while they hide their own secret vaccinations.

...

Too band we cannot isolate us or them to be done with the PURG. Cleansing the gene pool from time to time and now is a good time.

 

[Darenwh]

I am really having a hard time feeling bad for antivaxxers who get this disease. It is hard to care for somebody who refuses a way to prevent or greatly lessen the severity of an infection because of fears of unproven and extremely rare side affects. It is sad though for their children. As for lawmakers and media personnel who have pushed against vaccines, masks, etc…. Are they truly so dumb as to not realize that every time somebody dies who took their advice they not only lose that persons vote or viewership but likely many or even all the votes and viewership of those people who may have cared for that individual And could be blaming the politician or media personnel/outlets For the persons death. I have actually given up watching Fox programming of all types due to Fox News…

 

[Mr._Clark]

The latest risk levels map shows that the virus is spreading in the south and up through Missouri and Arkansas. Texas had almost no "red" counties until a few days ago. This pattern is somewhat similar to the pattern last year.

Risk Levels - Global Epidemics

RISK LEVELS First published in July 2020, our COVID-19 risk levels dashboard served as a tool for the public to track the pandemic in real time. As the pandemic has evolved and testing and reporting data have changed significantly, we have retired the dashboard as of December 2022. To explore...

globalepidemics.org

 

[Mr._Clark]

I am really having a hard time feeling bad for antivaxxers who get this disease. It is hard to care for somebody who refuses a way to prevent or greatly lessen the severity of an infection because of fears of unproven and extremely rare side affects. It is sad though for their children. As for lawmakers and media personnel who have pushed against vaccines, masks, etc…. Are they truly so dumb as to not realize that every time somebody dies who took their advice they not only lose that persons vote or viewership but likely many or even all the votes and viewership of those people who may have cared for that individual And could be blaming the politician or media personnel/outlets For the persons death. I have actually given up watching Fox programming of all types due to Fox News…

The abject stupidity of some people is almost incomprehensible:

>>>Known for its Cajun cuisine, Shorty Pants was brimming with customers on a recent weeknight. . . . Inside, McNay sat along with a half a dozen other customers who likewise lamented, what they viewed as, a breathless push for vaccines. Two bartenders floated in and out of the conversation, dropping comments like “what’s Covid?” to laughter. Just recently, a beloved cook at the restaurant had died from the virus, they said. But that hadn’t changed the thinking around vaccinations. . . .

“The irony is it’s not the dumb rubes in Missouri who don’t understand the nature of this disease,” Gregg Keller, a longtime Republican consultant in Missouri. “Missourians understand this far better than these supposed medical experts we’ve been giving tens of millions of dollars every year.” <<<

‘What’s Covid?’ Why People at America’s Hardest-Partying Lake Are Not About to Get Vaccinated

At the Lake of the Ozarks, vaccines are shunned, masks are mocked and the long-term consequences take a back seat to the time at hand.

www.politico.com

 

[Mr._Clark]

It's also interesting how contradictory a lot of it is. From the Politico article:

>>>“I think the left is trying to extend the virus for political gain,” said Rick Shiman. Shiman did get the vaccine, in part because Donald Trump was behind developing it, he said. But he doesn’t necessarily think it’s needed. “All this bullsh*t about people getting sick, look around,” he gestured over to the crowded pool, “See any masks here in Missour-ah? Not one. Is anybody getting sick? No. They’re full of sh*t on the left.”>>>

Ted Cruz last year:

>>>"If it ends up that Biden wins in November...I guarantee you, the week after the election suddenly all those Democratic governors, all those Democratic mayors, will say, 'Everything is magically better. Go back to work, go back to school.' Suddenly, the problems are solved," Cruz said in the July 22 clip.<<<

Clip of Ted Cruz Saying Dems Would Say COVID 'Magically Better' Resurfaces

"You won't even have to wait for Biden to be sworn in. All they'll need is Election Day," the GOP senator predicted in July.

www.newsweek.com

 

[mtrycrafts]

...

View attachment 49533

Do you have a link for this? Wife is very interested to know.
Thanks.

 

[TLS Guy]

Since I last posted the situation is worsening in most parts of the US fast.

When I last posted a couple of days ago the positivity rate in Dakota county where I live was 2.5% indicating relatively low community prevalence and spread. Today it 6.8% and rising fast, pretty much all Delta Variant.

So the entire metro is now asked to mask up in indoor settings and in 35 Minnesota counties in total.

Looking at the and UK data, the highest rate of infection is peaking at about 24 years of age, indicating this is an illness, mainly of the young and not the old.

Those in the ICU and hospitals are now predominantly below 50 years of age, with many between 40 and 50.

Now the number of people infected from one individual, has been found to be much higher than thought. The alpha variant, one would infect three, for the Delta variant one infected individual will infect nine. So it is easy to understand why there is just a rapid rise in cases. The case fatality rate is dropping. This is because the seriously ill population is much younger and there are fully vaccinated break through cases in the mix, which have a very low mortality and only make up 0.5% of the deaths, current data would suggest. However patients are getting infected with much higher viral loads, which is not good.

The Provincetown outbreak, has provided really important data, and has been obtained to large degree, because of citizen science, from outstanding community action and data collection.

In 833 cases 74% were fully vaccinated. Virus shedding surprisingly was as high in the vaccinated as the unvaccinated. That is very unfortunate as far as limiting spread.

The good news is that all the serious cases were in the unvaccinated. 197 were admitted to hospital, 40 are in ICU and 21 have required mechanical ventilation.
So far none have died, as far as I can tell, but there may well be some deaths in the ventilated patients over the next couple of weeks.

Now I should make one point at this time. What medical personnel call a mild case and the public call a mild case are significantly different. What medical personnel call mild, members of the public call very nasty. So it is not something you should go looking for. However it will probably be hard to escape, given that it is as infectious as chicken pox, where you only have to walk past an infected person to catch it.

Israel has data, that breakthrough cases seem to be commoner at 5 months past full vaccination. If this holds up, that is more bad news. In any event Israel are now giving boosters to people over 60 more than 5 months past full vaccination.

All the above makes it really imperative that everyone gets vaccinated. We do need to get 90% full vaccination over the next six weeks.
Everybody, yes, everybody needs to confront those not vaccinated. It is time for businesses to deny access to the unvaccinated. It is totally irresponsible now, not to be vaccinated.

Obviously in view of current data, change in behaviour is now called for.

Masks, need to warn by ALL in indoor settings out of your home. I would avoid bars, concerts cinemas, and churches, etc until cases drop significantly and certainly while cases are exploding at the current rate. I think we will go back to curbside shopping.

I watched the Minnesota Orchestra concert this evening, the second after the audience was allowed back in. I noted more empty than occupied seats, indicating people must be concerned. So economic impact still continues.

Things are certainly much more hopeful than they were are year ago, but we certainly are having an unfortunate set back. A lot of this, if not most of it, would have been avoided if vaccinations had not stalled.

 

[Swerd]

Do you have a link for this? Wife is very interested to know.
Thanks.

Herd immunity - Wikipedia

en.wikipedia.org