SARS-CoV-2 Coronavirus (COVID-19)

Infection-enhancing anti-SARS-CoV-2 antibodies recognize both the original Wuhan/D614G strain and Delta variants. A potential risk for mass vaccination ?

https://www.journalofinfection.com/article/S0163-4453(21)00392-3/fulltext

 

Abstract
Could some vaccines drive the evolution of more virulent pathogens? Conventional wisdom is that natural selection will remove highly lethal pathogens if host death greatly reduces transmission. Vaccines that keep hosts alive but still allow transmission could thus allow very virulent strains to circulate in a population. Here we show experimentally that immunization of chickens against Marek's disease virus enhances the fitness of more virulent strains, making it possible for hyperpathogenic strains to transmit. Immunity elicited by direct vaccination or by maternal vaccination prolongs host survival but does not prevent infection, viral replication or transmission, thus extending the infectious periods of strains otherwise too lethal to persist. Our data show that anti-disease vaccines that do not prevent transmission can create conditions that promote the emergence of pathogen strains that cause more severe disease in unvaccinated hosts.


Not sure if this is applicable in a disease that struggles to break into the 1-percent club......

 

Above my pay grade

 

Abstract

Antibody dependent enhancement (ADE) of infection is a safety concern for vaccine strategies. In a recent publication, Li et al. (Cell 184 :1-17, 2021) have reported that infection-enhancing antibodies directed against the N-terminal domain (NTD) of the SARS-CoV-2 spike protein facilitate virus infection in vitro, but not in vivo. However, this study was performed with the original Wuhan/D614G strain. Since the Covid-19 pandemic is now dominated with Delta variants, we analyzed the interaction of facilitating antibodies with the NTD of these variants. Using molecular modelling approaches, we show that enhancing antibodies have a higher affinity for Delta variants than for Wuhan/D614G NTDs. We show that enhancing antibodies reinforce the binding of the spike trimer to the host cell membrane by clamping the NTD to lipid raft microdomains. This stabilizing mechanism may facilitate the conformational change that induces the demasking of the receptor binding domain. As the NTD is also targeted by neutralizing antibodies, our data suggest that the balance between neutralizing and facilitating antibodies in vaccinated individuals is in favor of neutralization for the original Wuhan/D614G strain. However, in the case of the Delta variant, neutralizing antibodies have a decreased affinity for the spike protein, whereas facilitating antibodies display a strikingly increased affinity. Thus, ADE may be a concern for people receiving vaccines based on the original Wuhan strain spike sequence (either mRNA or viral vectors). Under these circumstances, second generation vaccines with spike protein formulations lacking structurally-conserved ADE-related epitopes should be considered.

 

that didn't help, much

but i'm not on the vaccine development team, and a good thing too

 

Six Month Safety and Efficacy of the BNT162b2 mRNA COVID-19 Vaccine | medRxiv

Six Month Safety and Efficacy of the BNT162b2 mRNA COVID-19 Vaccine

 

No wonder you are confused. The "flatten the curve" was specifically so that we could "keep ERs from overflowing into the parking lot". We did a good job in the SF bay area the first time. As I recall, we had a few periods of time where individual hospitals had to divert patients to other nearby hospitals but on a county by county basis we did OK.

I'm hoping that we can do that well as we move forward. There are many cities that are buying into the idea that proof of vaccination might reduce the spread of the disease. I guess that death is not enough of a deterrent to convince some folks to get vaccinated and use a mask. There is some evidence that being blocked from karaoke night at the local bar will convince them that it's time to do what's right.

 

That's for sure. I haven't heard of one person in that condition getting vaccinated or using a mask.

 

'louisiana shipping covid patients to texas'

 

Since making that post (image from worldometers.com), I've now learned that Florida's daily reporting has recently become 'chunky'. Both worldometers, and your github/NYT sources, betray multiple consecutive days of no reports at all from Florida, then a burst of increases for several days. JHU shows what appear to be just once-a-week updates:


and includes this under Notes:

"August 7, 2021

• The data for August 5, 2021, includes the past week's worth of data from Florida. Florida only reports COVID-19 data once per week via their COVID-19 Weekly Situation Report, and does not provide a daily back-distribution of Case or Death data. While not all of Floridas Cases/Deaths were diagnosed/occurred on August 5, we are unable to break them out to dates within the week."

Less frequent updates will make comparisons and trend watching more difficult.

 

Perhaps less difficult watching may return:

Miami Herald: DeSantis says reporting local COVID data on daily basis ‘may not be a bad idea’

I suppose we could do some de-chunking just by comparing in multiples of seven days.

US 8/6 to 8/13: 616257 to 620813, increase of 4556

FL 8/6 to 8/13: 39695 to 40766, increase of 1071

So not 35% as the 'chunky' version suggested, but about 24% of the US increase for the week.

A two-week window:

US 7/30 to 8/13: 612775 to 620813, increase of 8038

FL 7/30 to 8/13: 39079 to 40766, increase of 1687

FL's proportion of US total new deaths over the longer two-week window is a little lower, about 21%, compared to 24% over just the most recent week, as would be expected as their rate continues to outpace the overall one.

 

cdc allowed regeneron for immunosuppressed last week. they have a link to storage sites.

seem to be reserving them for the sickest otherwise. too costly?

 

ma stopped weekend reporting in the spring, knowing that delta was on the rise. they also stopped individual hospitalizations/icu/vent reporting and just report totals for the state.

penny pinching in hopes it will just go away?

meanwhile, my own hospital system started allowing 2 visitors a week ago, then reversed back to 1 today.
i had a scheduled colonoscopy yesterday with covid test required prior to. they changed it to no covid test required, but i expect that will change again as well.
i think there is still a lot of confusion, even among professionals.

pre colonoscopy, the nurse is asking me about covid symptoms or contact. i told her the most dangerous place i've been is there.
she said it was completely safe, and they were all vaccinated (they are not)
i said what about all the patients? she said, 'oh yeah', and shrugged.

 

It is typical of times COVID and pre-COVID for 50-100% of patients in an ICU to be on a ventilator. Mechanical ventilation is a last ditch effort, but that is where a certain percent of hospitalized COVID patients ultimately progress to despite best treatment practices.

Most COVID patients can be managed in the hospital out of the ICU with low to high flow oxygen from nasal cannula or face mask. But if/when things get bad enough, it's time for a pressure mask fitted to the nose/mouth called CPAP or BiPAP that can also deliver 100% O2. If things turn around after a few hours on CPAP/BIPAP, great. But often patients still tire with this mode and can't keep their O2 sats up, then mechanical ventilation is the last option left.

 

I showed figures for Aug. 8, which apparently was still bulloxed by this incident:

"Earlier this week, DeSantis signaled he may be willing to directly report Florida’s case numbers to the public after the CDC incorrectly reported Florida’s case data for the weekend of Aug. 7 and 8. The figures have since been corrected."

 

Apparently the latest not-yet-released data suggests that immunities are indeed waning quickly. That led to yesterday's announcement that booster shots are expected to start late next month. Supporting data to be released later this week. From Politico:

Troubling CDC vaccine data convinced Biden team to back booster shots
The evidence showed a decline in the initial round of protection against Covid-19 infection that's coincided with a resurgence in cases driven by the more contagious Delta variant.

"Top Biden administration health officials concluded that most Americans will soon need coronavirus booster shots after reviewing a raft of new data from the Centers for Disease Control that showed a worrying drop in vaccine efficacy over time, four administration officials told POLITICO.

The evidence, compiled by federal scientists over the past several months, showed a decline in the initial round of protection against Covid-19 infection that's coincided with a resurgence in cases driven by the more contagious Delta variant. The data looked at vaccine effectiveness in individuals across age groups, with varying medical conditions and who received the shot at different times. It was presented to White House Covid-19 task force officials at a meeting Sunday.

“This is what moved the needle,” one senior administration official said, describing the CDC data and the decision to urge boosters.

That data — which is set to be made public later this week — brought a swift end to a debate over when to administer boosters that has raged within the administration for months, and spurred the buildout of a plan for distributing the additional shots in a matter of weeks. ..."

 

Sounds good to 71 year old me.

Bob Wilson

 

Wow.
Good look USA!!

"Low income" nations are clamoring for their FIRST dose, and now Americans are lining up for their third.......