Coronavirus Pandemic (COVID-19) (SARS-CoV-2) [2020]

Preprint of study out of Los Angeles shows presence of antibodies in oral and nasal mucosal fluid, i.e. the upper respiratory tract:

To test that hypothesis, we enrolled 114 participants within 3-7 days of receiving the first dose of the Moderna mRNA COVID-19 vaccine and collected oral mucosal fluid samples on days 5, 10, 15, and 20 after each vaccine dose. Of participants naive to SARS-CoV-2 (n = 89), 79 (85.4%) tested positive for SARS-CoV-2 IgG antibodies by time point 2 (10 days +/-2 days after first vaccine dose), and 100% tested positive for SARS-CoV-2 IgG by time point 3 (15 days +/-2 days after first vaccine dose). Additionally, we collected paired oral mucosal fluid and anterior nares samples from 10 participants who had received both vaccine doses. We found that participants had an average SARS-CoV-2 IgG antibody concentration of 2496.0 +/-2698.0ng/mL in nasal mucosal fluid versus 153.4 +/-141.0ng/mL in oral mucosal fluid. Here, we demonstrate detection and longitudinal persistence of SARS-CoV-2 IgG antibodies in upper respiratory tract specimens following COVID-19 mRNA vaccination.


https://www.medrxiv.org/content/10.1101/2021.05.06.21256403v1

In the text of the study itself, the authors issue these caveats:

High antibody concentration at the sites of the primary infection may play a direct role in
preventing viral transmission. Additional in-vitro experiments to study the effects of treating
SARS-CoV-2 viral cultures with oral mucosal samples from vaccinated individuals would be
required to test this hypothesis.

Also the age of the group studied skewed young and relied on their ability to collect samples:

This study had several limitations. Due to our enrollment of health care workers, the average
age of participants was low, with only 8 participants over the age of 50 years and only 1
participant over the age of 65 years.
Participants were not monitored during specimen collection
after the first time point, but the ability of participants to follow instructions for unobserved
collection was validated internally prior to sample collection.

https://www.medrxiv.org/content/10.1101/2021.05.06.21256403v1.full.pdf

But still a very hopeful sign that mRNA vaccines may produce upper respiratory tract protection, though I believe there was also a concern that antibodies in the mucosal linings tended to wane much faster than antibodies elsewhere.
 
Public Health England analysis indicates that one dose of the AZ vaccine provides an 80% protection in the risk of death. One dose of the Pfizer vaccine provides a similar 80% protection with 2 doses providing a 97% protection.

Further analysis also indicates an 93% reduction in the risk of hospitalisation in the over-80s after 2 doses of the Pfizer vaccine.

I'd imagine more data (albeit with wider confidence bars) will be available for the AZ vaccine before too long now that a lot more people have received 2 doses of this vaccine. I'd imagine the great reduction in the number of cases in the UK will make the data less certain, however. Will be interesting to see if it can get anywhere near the 97% number indicated for the Pfizer vaccine.

Good news all round. Here's the press release with links to the data, if anyone is interested:

https://www.gov.uk/government/news/covid-19-vaccines-further-evidence-of-success
 
Well the UK is patting themselves on the back for the gamble they took.

In any event, the EU has made a deal for 1.8 billion more doses of Pfizer and declined to buy more doses of the AZ.

There is a belief that AZ could provide better T cell response, which might lead to longer protection, while the Pfizer generates more antibodies, which would be why it's shown in studies to have higher efficacy vs. the variants.
 
Pfizer are certainly doing incredibly well to be able to increase production levels so well. I've read that they didn't have time to develop a production-level piece of equipment (something to do with lipid blending, I think) so have instead simply mass-produced the small development prototype!

I see Inovio have announced further positive results from the Phase 2 trials of their DNA vaccine:

https://www.prnewswire.com/news-rel...-4800-its-covid-19-dna-vaccine-301287416.html

A fancy intradermal injection is used for this one. Let's hope the Phase 3 trials go well and it proves effective.

Unfortunately, it looks as though Novavax have kicked the can down the road again. Probably won't be applying for an EUA until the 3rd quarter. Though they have announced positive preclinical data for a combined Covid/Flu vaccine. That would certainly be a good idea, reducing visits, saving staff time and saving scarce resources such as the needles and vials.

All we need now are some cheap and effective treatments and we'll be well on the way to dealing with the pandemic. Too late for many in developing countries, however. I fear the surges we're seeing on the Indian subcontinent could be replicated elsewhere, with many African countries particularly at risk.
 
Delaying a COVID vaccine’s second dose boosts immune response
Older people who waited 11–12 weeks for their second jab had higher peak antibody levels than did those who waited only 3 weeks.

https://www.nature.com/articles/d41586-021-01299-y

And Lower Saxony will throttle assignment of appointments for the first jabs in favour of the second jabs. And starting next week I can register for my first jab...
 
Only problem is you may be more vulnerable during those 3-12 weeks when you otherwise would have the second shot.

If boosters are inevitable as some experts believe, then maybe waiting longer for the second shot doesn't make as much sense.
 
I suppose it depends on how much it affects the other parts of the immune response, not just the antibodies. The study mentions that the T-cell levels were lower with the extended dosing period, but how much will this affect immune response?

There's another study out showing that mixing vaccines leads to more frequent post-immunisation side effects:

https://www.theguardian.com/society...g-pfizer-and-oxford-covid-jabs-study-suggests

I wonder if the immune response will be improved with this mix and match approach? Too early to know as yet.

In other news, the Indian variant B.1.167.2 is surging in areas of the UK and it is belived that this indicates it is more transmissible than the B.1.1.7 'Kent' variant - potentially up to 50% more transmissible, in fact. Talk of matching it with a vaccination surge for younger adults in these areas, but it doesn't really seem worth it to me. There won't be a significant immune response for a few weeks (at least) after immunisation which would potentially give the variant the chance to really take off in any case. More localised restrictions would seem to be more sensible. Not going to happen, however.

It goes without saying that the UK has let the various Indian variants take hold in the country much too easily, just as we have done with imported infections throughout the course of the pandemic.
 
There's a surge of community transmissions in Taiwan recently. It's likely originated from an airline pilot flying cargo.
An additional complication is that many people in Taiwan didn't feel the need to get vaccinated because there's so few cases. Even high risk groups such as airline pilots were hesitant.
The fact that the government wasn't able to get enough vaccine is not helping. It's a dilemma: you have very few cases so why do you need those vaccines? You should let countries like India get them first! Now we can't get enough people to get vaccinated.
A few domestic pharmaceuticals were already developing vaccines, but it can be quite difficult to get trials when you have very few positive cases. The trials have to be done in foreign countries. It's expected to be ready as early as July, and there's still manufacturing challenges.
It's just starting and it's weekend so I don't know how worse it could be, but I guess we'll see, in a few days.
 
Yeah it's a strange attitude.

There have been hundreds of millions of people vaccinated around the world.

Some people were vaccinated about a year ago, in the early trials.

So if vaccinated people were going to grow tails, it would have happened by now.

Sure they could wait years to see if the vaccines have long-term effects. But do they want to be shut down for years? Remember, India thought it was doing great until it wasn't.

All these Asian nations which have controlled the pandemic are tempting fate by being slow with vaccinations.
 
Indonesia is back to normal
  • Tourism sites are full of people with no face mask, no social distancing
  • boats are full (one of them even capsized due to overload)
  • People visits each other due to "end of holy ramadan month" culture.
Hospitals are overloaded
 
Yeah it's a strange attitude.

There have been hundreds of millions of people vaccinated around the world.

Some people were vaccinated about a year ago, in the early trials.

So if vaccinated people were going to grow tails, it would have happened by now.

Sure they could wait years to see if the vaccines have long-term effects. But do they want to be shut down for years? Remember, India thought it was doing great until it wasn't.

All these Asian nations which have controlled the pandemic are tempting fate by being slow with vaccinations.

In Indonesia:
  • The rumour was that they became Titan, not growing tails
  • The vaccine is limited to public servants, doctors, and people older than 60yrs old.
  • Vaccine for public is scheduled to start on August.
 
There aren't enough (good) vaccines to go around and people are dead tired of restrictions. It sucks but we will probably see a lot more infected in places that were doing really until now.
 

It certainly seems as though B.1.617.2 is more transmissible than B1.1.7, but it's difficult to say just how much yet. The early analysis from UK numbers indicating it could be up to 60% more transmissible could be misleading as it turns out that the wonderful £37 billion test and trace system in the UK messed up and didn't pass information on to the local public health authorities about hundeds of those infected so no tracing of contacts was taking place. This reportedly included around 300 positive results from the Blackburn & Darwen area where we're seeing the largest surge of B.1.617.2 in the UK:

https://www.theguardian.com/world/2...-blamed-for-spread-of-indian-variant-of-covid

This could certainly have contributed to some of the surge in infections we've seen. Still, it looks like there is something else going on with this variant, that's for sure.

On a more positive note (especially for me, as I've had this one!), analysis from Public Health England indicates that 2 doses of the AZ vaccine are 89% effective at preventing symptomatic disease which is similar to the numbers for the Pfizer vaccine. Usual caveats that we don't know how long this protection will last. It also seems that protection after a single dose of the Pfizer vaccine drops off around the 10 week mark which is why they are moving up the schedule to 8 weeks for the over-50s.

The other positive is that the WHO Europe regional director has said that they believe the approved vaccines are effective against all the current known variants:

https://www.reuters.com/business/he...-against-variants-who-europe-says-2021-05-20/
 
Investigation of novel SARS-CoV-2 variant - Variant of Concern 202012/01 (publishing.service.gov.uk)

Jump to the page 41.
PHE has undertaken analysis of vaccine effectiveness against symptomatic disease with VOC21-APR-02 (B.1.617.2), using the national genomic and immunisation datasets. The full methodology and analysis will be published here. These findings suggest that while there is a reduction in vaccine effectiveness against VOC-21APR-02 (B.1.617.2) after one dose, any reduction in vaccine effectiveness after 2 doses of vaccine is likely to be small (Table 9). These data combine all vaccines, and a breakdown by vaccine is provided in the full analysis.

Got my first BNT jab on friday. And I regret it a little bit, I should wait for J&J - one shot and you are fully vaccinated.
 

Total shit show. They left it way too late until they decided to block travel from India.

Thank god I got my second Pfizer dose this week, but even then it’s unclear if I’ll be able to get around the very expensive and painful process of getting multiple tests for my trip next month.
 
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