Welcome to another MedCram COVID-19 update. And while the numbers are staggering as to the number of global cases and global deaths, it seems as though the numbers are starting to come down. In the United States, daily new cases have dropped precipitously, as have the daily new deaths. You can see, for instance, in California, daily new cases continue to fall. Daily new deaths in California continue to tick down overall. In fact, in San Bernardino county, where I work here in southern California, there's been a sharp decline in hospitalizations from COVID-19.
The UK has also seen a drop in new cases, as well as a drop in daily deaths in Spain. Daily new cases also continue to drop, as do daily new deaths in Spain. But there are spots around the world, where this is not happening as precipitously. For instance, daily new cases in Brazil seem to have leveled off and are not coming down. The same can be said for daily new deaths in Brazil. In Germany, where cases have fallen, there seems to be a leveling off or plateauing of the daily new cases.
This is while daily new deaths in Germany continue to fall. Is there more information behind this trend? Well, as it turns out, there is some information. Authorities are noticing that COVID infections are rising again in Germany, just as schools are planning on reopening in 10 of 16 states in Germany, and experts believe that what's driving this is more infectious variants of SARS-CoV-2. And specifically, in this story by DW, the concern is that it's the UK variant spreading in Germany that's causing this increase in cases.
Now, at a press conference, the German Health Minister, Jens Spahn, told reporters that 22 percent of all the new infections in Germany was related to the B117 coronavirus variant. And realize that just two weeks ago, this variant was only six percent of new infections in Germany, so they've got to assume, according to the Health Minister, that this variant is soon going to become the dominant variant in Germany and perhaps around the world, as well as potentially other variants --for instance, the one from South Africa. And as a result of this, Germany is currently banning travel from Austria and Czech Republic regions, and remember that all this is happening amongst the push for elementary schools in germany to reopen.
Guess a possible answer is going to be to accelerate vaccination of teachers to keep schools open. And of course that is the same question that we have here in the United States, and here you can see a map showing the 50 states, whereas you can see in gray there is no state order either way to open or close the schools. And so it's left up to the counties and the school districts. Notably the squares that are colored either show in green that they've been ordered to be reopened, orange that there's a partial closure in effect, red shows full closure in effect, or the lighter orange in West Virginia, for instance, where some grades have been ordered open.
The big question right now is whether or not this decrease in the numbers is going to stick around for a while or if it's just a pivot point and we're going to go back up again with the variants. And this Medical News Today article actually went a long way in looking at the current data and telling us how well the vaccines are going to hold up against these variants. So there are currently three different variants that we're concerned about. There is the B.1.1.7 variant, there is the B.1.351 variant, and then there is the P.1 variant. Now the B.1.1.7 variant is from the UK, the B.1.351 variant is from South Africa, and the P.. variant is from Brazil. And of course the two vaccines that we currently have available in this country.
The United States is the Pfizer vaccine and the Moderna vaccine. Now there is some emerging evidence that these current vaccines have efficacy against these variants, so here's a paper that was published on the 29th of January 2021, looking specifically at that B117 UK variant and the Pfizer vaccine, and if you look at the abstract, it calls out this B117 variant. And what they do here in this study is they tested the SARS-CoV-2-S pseudoviruses that have this strain or the B.1.1.7 lineage spike protein with the serum of 40 participants who were vaccinated in a previously reported trial with the Pfizer vaccine, and they showed that the immune sera had slightly reduced, but overall largely preserved neutralizing titers against the B.1.1.7 lineage pseudovirus, concluding them to say that these data indicate that the B.1.1.7 lineage will not escape the Pfizer-mediated protection.
Here you can see a graph of the pVNT50, which is basically a way of quantifying neutralizing antibodies. And as you can see here, the reference between the initial Wuhan reference virus and the B.1.1.7 variant, the difference is very, very small. Here's another paper that was published, this time in Cell titled "Reduced neutralization of SARS-CoV-2 B.1.1.7 variant by convalescent and vaccine sera," and even though the B.1.1.7 was harder to neutralize than the parental virus, they did not notice widespread escape from monoclonal antibodies or antibody responses generated by natural infection or vaccination.
So if we go back to our chart, it looks like we're okay here in this situation, meaning that the Pfizer vaccine seems to be able to take care of the B.1.1.7 variant. Well, what about Moderna? How does it fare against these variants? Now, there is a paper that has not been peer reviewed or published, but is on the MedRx server titled "mRNA-1273 [which of course is the Moderna vaccine] induces neutralizing antibodies against spike mutants from global SARS-CoV-2 variants." And in this study, what they did was they assessed the neutralizing capacity of sera from human subjects and non-human primates that received the Moderna vaccine, and what they found was that there was no significant impact on neutralization against the B.1.1.7 variant.
They did notice that there was an impact on neutralization somewhat on the B.1.351 variant, but taken together, they said these data demonstrate reduced but still significant neutralization against the full B.1.351 following the Moderna vaccination. And of course this preprint led them to release a press release titled "Moderna COVID-19 Vaccine Retains Neutralizing Activity Against Emerging Variants First Identified in the U.K. and the Republic of South Africa." And in this release, they're pretty confident that the Moderna vaccine is going to be very good still against the B.1.1.7 variant.
They also make that somewhat against the B.1.351 variant -- the one from South Africa -- however, they did notice that there was an antibody titer that was approximately six-fold lower relative to prior variance. And they say here that these lower titers may suggest the potential risk of earlier waning of immunity to the new B.1.351 strain. So if we look at the B.1.1.7 from the UK, it looks as though we're good for the Moderna and plus- minus on the South African B.1.351 variant. But, remember that something that both Pfizer and Moderna would want you to remember, of course, is here we're just looking at b cells in terms of antibody titers. What this does not take into consideration is T cell response, and remember there is a T cell response to these vaccinations.
Currently, we don't have data on the P.1 variant, so time will tell whether or not the vaccines that we currently have are going to be effective enough against these variants. Wut what are the vaccine manufacturers doing just in case? In fact, what they're doing is they are taking another look at those variants and coming up with a quote "copy and paste" way of producing a booster that will be effective against those variants.
In fact, both companies, Pfizer and Moderna are looking at doing that in about six to nine weeks by sequencing the RNA of the portion of the genome in the SARS-CoV-2 that makes the spike protein in a modified variant way. We can now engineer the appropriate vaccine so that the response against that vaccine is more robust than the current vaccine model. For more information subscribe my blog.
No comments:
Post a Comment
wgdyrj@gmail.com