Future Covids and Vaccines

Summary

The rapid availability of vaccines for Covid19 shows how far the technology has progressed. Previously, mainly due to red tape for approval, it took about 10 years. Most successful are the mRNA (messenger RNA – synthetic and genetically engineered) types from Pfizer and Moderna.

But Pfizer’s vaccine needs to be stored at –70^∘C and Moderna’s at -15^∘C, both with expiry times of 6 months.

AstraZeneca, a more conventional vaccine can be stored from 2^∘C to 8^∘C for 8 months. It is made from a weak version of the cold virus from chimpanzees, plus genetic material from Covid19. There are others, such as Novavax, an mRNA type that is good but got approval a bit late, Johnson and Johnson, etc. However, this blog is about future versions to combat variants, like Delta. There are about 240 new vaccines in development!

The video below explains the effectiveness of the ones we have now. Variants such as the Delta strain are more transmissible which means vaccines need to be modified quickly just as ‘flu vaccines are. AstraZeneca has recently been found to be more effective against the Delta strain – Click Here

Video: Testing and Efficacy or Effectiveness:

New Vaccines In Development

Only novel types with seemingly big advantages are described below. The incentive is there. Pfizer’s income for the Covid 19 vaccine is expected to be about US$26 Bn, just to the end of 2021.

Tablet Vaccines

This is a pill, stored at room temperature and easily modified for new strains. It is too early to tell whether these different vaccines like the pill and the nasal spray below will be effective. However, the aim is to make vaccines simpler, enabling easy distribution and ingestion. More people will get vaccinated, as no needles are involved and trained people are not needed for injecting. They are easily stored, transported and low cost, so suitable for poorer countries such as Africa, South America and Indonesia. No data is available yet as to expiry times for these simpler vaccines.

Nasal Spray Vaccines

While needle vaccinations into the bloodstream are quite effective in stopping hospitalisation and death, new research shows there may be better methods and types. Initial nasal spray vaccines in animal trials show 100% protection and can be self-administered, with no negative side effects. Some are also sprayed orally. To be safe, it seems logical both nasal and oral spraying is required.

Vaccines that are injected into the arm, including the ones for Covid19, do a great job of producing antibodies in the bloodstream. But they don’t generate high levels of antibodies in the nasal passages, which is where Covid19 is most likely to enter the body.

There’s already a nasal spray flu vaccine called Flumist, which is used now.

“When you get an infection, you get it in your mucosal surfaces in your nasal cavity, and you prime your T cells and your entire immune system in your upper respiratory tract, which means these cells are going to stay there, become resident, and act as a sentinel defence,” says Marcus Buggert, an immunologist and T cell researcher at the Karolinska Institute in Sweden. “If you vaccinate yourself in the arm, you won’t induce that type of T cell response.” Apparently, there are T cells in the nasal cavity skin.

At present nasal spray vaccines are conventional like Astra Zeneca, but a nasally delivered mRNA-based vaccine is possible. It likely would require tweaks as is done in injectable Covid19 vaccines.

Unanswered Questions

 Concerning the new non-injection vaccines, Google doesn’t say why:

• These vaccines weren’t researched earlier or is there some problem yet to be discovered?
• Room temperature storage is fine, but not for some of the injectionable ones?
• How many ‘shots’ will be needed and how long they last?

Perhaps future research will tell all. I am no expert in this field, so If you know any of the answers, please comment below.

 References

• Scientific American
• ABC
• Health NSW Gov
• Pfizer
• BioPharma
• National Geographic