Vaccinations

mRNA vaccinations

Usually vaccines come from a made safe virus, or surface protein piece of it.
The mRNA makes a code for a piece of that spike of protein, injected into the human, code into the cells, which is a blue print to make these spike proteins, provokes the normal immune response.
Antibodies, small protein molecules, produced by immune cells called B cells (live in spleen and bone marrow). B Cells secrete antibodies when exposed to virus. T cells can kill virus, two types, T Helpers, like conductors, and CDA cells actively kill the virus cells. Other cells …. All bits of immune system work together. Short lived and long lived cells, like different batteries, short sharp need and longer need.

Can it insert itself into our genome?
No only specific to this job, and specific set of instructions. Considered to be very safe.

Rolling out: Rather than having to grow a virus, this can be done in a lab, shorter simpler process. However, -80 degrees is challenging. 50 million

Risk: 90% efficacy. Case Control 45,000. Of those 94 got Covid. Of those 90% had had the placibo, only 10% had the active vaccine, and got sick. Very surprised. Usually around 40-60% efficacy. Malaria 50-60%.

How will it spread around the world?
COVAX initiative wealthy countries securing for themselves and less wealthy states.

How long will the immunity last?
Long lived B cells. What happens to them in COVID? At the moment we know they last for 6 months. Prediction bassed on other models, other virus behaviour, is that there will be some long lived B cells. However COVID goes deeper into our system than the more common Coronaviruses, deep into our bronchial. SARS COVID 2 the virus that causes the COVID19, potentially has a poor long term response.

Differences in ethnic groups? There is a lot of genetic variation in immune responses, some of those differences have geographical genetic make ups. So far no direct links to ethnic groups.

Age related? Our ability to make a completely new response does decline as you get older. We are also less good at controlling inflammation.

Is the vaccine preventing us from getting or symptoms?
Too complicated to test for this. The driver is now is to stop people dying, then we can begin to see if there is a reduction in virus transmission.

Vaccinate gaps

Delay between 2 doses from 3 to 12 weeks. Pfizer objected. We are taking a punt.
Purpose of 2 vaccines: First time your immune system meets the vaccine it gets turned on, and lays down immune memory. Second time, does fancier stuff.
Consequences of shifting 3 to 12 weeks. The Oxford original trial included gaps in dosing, which found no difference in efficacy between these gaps, but unpublished gives a longer gap gives more efficacy. With Pfizer Biotech protocol was very clear 3 week gap. There is no other data.

Oxford and Pfizer do the same, but come from very different technologies. Pathway would be different.

Argument – needs must, rather than be perfectionist. Better to vaccinate double the people rather than half with full with full protection. After one dose at least some efficacy, 86%. We do not have the data to say it wouldn’t impact the efficacy. Best on best guess. Unlikely that the response would wane dramatically in the longer time. How many lives will we save? Efficacy – what are we measuring, a limitation of symptomatic disease? a limitation of death? But long COVID community says we are still open to this long legacy.

After a few early blips, the UK has done well in vaccine roll out. Let’s hope plenty of vaccine coming through, don’t let squabble undermine. Grab any vaccine offered under any protocol. Amazing how quickly trials worked out. Hope for high uptake.

Difference between Pfizer, Moderna, Oxford, Sputnik vaccines

Oxford-AstraZeneca
Between Oxford University and AstraZeneca, a British-Swedish pharmaceutical company based in Cambridge. November announced efficacy 70.4 per cent, (90 per cent in one dosing regimen, and 62 per cent in the other). Over 24,000 participants UK, Brazil and South Africa. (Further trials will include 60,000 participants from the United States, Kenya, Japan and India.)
Design: The vaccine is a genetically altered adenovirus that usually causes the common cold in chimpanzees but has been tweaked to carry the blueprints for part of the coronavirus known as the spike protein. When the vaccine enters the body it uses this genetic code to produce the surface spike protein of the coronavirus, inducing a response that readies the immune system to fight the coronavirus if infected.
Cheapest of the big three and can be stored at a standard temperature 2-8degrees
Rollout: 68 million UK citizens, two doses. Ideally in four months around 17 million vaccinations to be administered per month.

Moderna
US Massachusetts-based company
30,000 volunteers across the US, demonstrated a 94.5 per cent efficacy
Design: Unlike the Oxford-AstraZeneca vaccine, Moderna’s is based on ribonucleic acid (RNA), a molecule similar to DNA that is naturally generated by our bodies. Quick to produce, more effective, easily reformulated if virus mutates, remains stable at 2-8 degres.
Cost: Cost between $25 (£19) and $37 (£28) per dose.

Pfizer/BioNTech
New York-based pharmaceutical corporation Pfizer and German company BioNTech were the first to announce a potential vaccine for Covid-19 after their Phase III trial.
Trial: 43,000 trial participants, gave 90 per cent effective. Since then, Pfizer announced an updated efficacy rate of 95 per cent beginning 28 days after the first dose.
Design: Similarly to Moderna, the Pfizer vaccine is mRNA-based and works well in older, more vulnerable people. The Pfizer vaccine needs to be kept at a freezing temperature of -70 degrees Celsius and will degrade in around five days at normal refrigeration temperatures.

Sputnik
The vaccine’s developers, the Russian state-run Gamaleya Center
Russia is fifth on the list of vaccine makers, just behind GlaxoSmithKline Plc and Sanofi’s candidate in the rankings and ahead of the shots developed by Moderna Inc. and Johnson & Johnson. This is notable for a vaccine that has yet to be featured in any peer-reviewed scientific journal. How do we know we can trust it? No Phase III data, only newspapers.
Efficacy at each interim analysis in the Sputnik V trial was consistently at 90% or above, with no cases of severe Covid-19 in vaccinated individuals, though definitions of disease severity are not clear.
Design: similar approach to Oxford, but instead of using adenovirus vectors from chimpanzees it is based on two human adenovirus vectors. Two-dose vaccines use adenoviral vectors — viruses based on the cause of the common cold that are engineered to deliver the genetic material coding for the Sars-Cov-2’s key “spike” protein, which in turn prompts the immune system to mount a response to protect against further infections.
Sputnik V has one key, clever difference from the Astra and J&J vaccines: It uses the same adenovirus as J&J for the first dose (adenovirus-26) and a different adenovirus (adenovirus-5) for the second dose. In this way, it avoids the possibility of immunity to the first dose impacting the ability of the second dose to work efficiently.

Sinovac Biotech Ltd. Chinese called CoronaVac / CanSino Biologics
Chinese firm CanSino Biologics
Trials in Turkey, Brazil and Indonesia. Phase III efficacy data for the CoronaVac shot has been all over the place – from 50% to more than 90% – with different numbers coming from different authorities in recent weeks. On Thursday, a Brazilian newspaper reported efficacy for the shot of 78%, adding to the confusion.