Are you uncertain about the new Covid-19 vaccine differences (or similarities); and are trying to work out what separates them – apart from their names?
What is it about the new vaccine development methods that separate them from the traditional, older ones? And - what are the advantages of the newer methods and lastly - are they MORE EFFECTIVE??
So many questions, but in this post we highlight the key areas that will interest you about some of the new Covid-19 vaccines differences.
What's On This Page
- Developing The Covid-19 Vaccines: Methods
- Gene-based Covid-19 Vaccines Differences - How They Work
- Are Gene-based Vaccines Different from Traditional (Protein-based) ones?
- Is One Vaccine More Effective Than the Other?
At this time, we have several different companies developing Covid-19 vaccines around the globe. We explain some Covid-19 vaccine differences paying particular attention to the recently released Pfizer BioNTech, Moderna and Oxford AstraZeneca vaccines.
Developing The Covid-19 Vaccines: Methods
With the evolution of medical technology we now have a group of vaccines that are different from the traditional, older groups.
Known as Gene-based technology, there are two categories:
- Nucleic Acid chains and
- Viral Vector groups.
1. Nucleic Acid Chains
It's important to know that we all have natural mRNA in every cell of our body.
The first group of vaccines, Nucleic acid chain is created using (man-made) messenger RNA (Ribonucleic acid) technology.
Theycontain genetic material that instructs our body to create proteins for many different activities like building, repairing and maintaining things in the body.
After decades of research, scientists can now create these genetic codes; allowing your body's cells develop specific protein types.
In the case of Covid-19 vaccines, the mRNA enable us develop the same (Spike) proteins found in the Coronavirus.
mRNA technology is responsible for the Pfizer BioNTech and Moderna Vaccines.
2. Viral Vector Vaccines
Scientists' discovery of the second category of Gene-Based Vaccine also follows decades of research and is known as a Viral Vector (carrier) method.
This is the method used to develop the UK Oxford AstraZeneca Vaccine.
The Viral Vector Vaccine transports the genetic material in a weakened or less harmful virus.
The adenovirus which causes the common cold in chimpanzees is used to carry the genetic material in Oxford's vaccine.
Meanwhile, this method is not entirely new - having been used to develop the Ebola vaccine last July.
Gene-based Covid-19 Vaccines Differences - How They Work
The way they work to create an immune response also differs - but just a little.
In both gene-based vaccine types, genetic material is used to stimulate an immune response.
Briefly, here's how they work.
Oxford AstraZeneca Vaccine
When you get an injection of the Oxford vaccine, you receive a piece of the SARS2 virus sequence carried on a harmless cold-causing adenovirus.
The virus sequence is based on the SARS2 Spike protein and is bound to the adenovirus's DNA.
When this enters your cells, the virus sequence on the DNA is used to create the Spike protein.
Your body identifies the spike protein and stimulates an immune response. The result of this is that your body's immune system develops a memory and now knows how to recognize the actual virus and create the necessary immune response to kill it.
PfizerBioNTech and Moderna Vaccines
When you get the shot of the Pfizer or Moderna vaccines, you receive the mRNA gene sequence for the SARS-2 spike protein wrapped in a fat capsule.
Think of the mRNA as a blueprint for protein development.
mRNA vaccines use the RNA sequence for a piece of the spike protein of SARS2, which is then read by the cell, replicated and finally discharged from the human cell.
After your cells create the virus Spike protein using the mRNA blueprint; they trigger an immune response.
This allows our immune system to form a memory that in future helps your body recognize and kill the actual virus.
Essentially, these three vaccines work by introducing genetic information to our body. The difference is that the Pfizer and Moderna vaccines introduce the genetic codes directly into the cells. Instead, Oxford vaccine uses a harmless virus as its carrier.
Are Gene-based Vaccines Different from Traditional (Protein-based) ones?
All this now leads us to ask how these gene-based vaccines differ from our older, traditional vaccines. You know; the flu vaccines, Tetanus, Hepatitis, HPV and so on.
Traditional vaccines are protein-based vaccines.
They either contain the Microbial Protein or inactive Microbe;
The newer ones only have the genetic codes necessary to manufacture the proteins inside your body.
Some like the Flu injection, Rabies or Hepatitis vaccines contain dead or inactivated viruses. Another group is made from live, attenuated or weakened germs. Examples of live attenuated vaccines are the Flu spray, Yellow Fever vaccine and Oral Typhoid vaccine. Another group contains subunits of the germs. For instance, the inactivated toxins they produce (DPT Diphtheria, Pertussis, Tetanus Toxoid); elements of the germ's surface (Meningitis and Pneumococcal vaccine). Another group is DNA combined with yeast cells such as with Hepatitis B; HPV or Meningitis vaccines.
Therefore, the primary difference is that the older viruses contain either elements of the germ - live or killed, while the newer ones do not.
Traditional vaccines are slower to develop compared to the newer ones. This is because it's more difficult to create the right proteins in the lab, and takes more time.
The mRNA codes are faster to develop when the viral sequence is known. They are easy to produce in mass even though the molecules are quite unstable hence the need for storage at very low temperatures.
Is One Vaccine More Effective Than the Other?
These three vaccines have not been compared directly to determine which is more effective than the other.
Different outcomes (measures) have been used to assess how effective they are - against becoming infected with Covid-19 and having a very severe infection or death.
You will hear that the Pfizer vaccine is 95% effective, or the Oxford vaccine is 91% effective.
These figures refer to how well each vaccine prevents severe Covid-19 infection development in trials where one group in the trial is given the vaccine, and the other group is not.
There may be findings in the future where we compare groups of people where one has the Pfizer vaccine versus the other who has the Oxford vaccine.
Until that time, whichever vaccine you get, we know they are over 50% effective – which is above the minimum requirement for use.
These are some of the differences with the latest Covid-19 vaccines. Does this make you feel more or less comfortable about taking them? Let us know in the comments section below.
We hope this helps you make your choice about taking the vaccine without fear. Watch our video here to learn more.
- Video - mRNA vaccines video - STAT -
- UK MHRA approves Oxford vaccine -
- Oxford Vaccine - Information For Health Professionals -
Editing by AskAwayHealth Team
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