The story of MRNA COVID-19 Vaccines

Tips for Health Workers to answer COVID-19 questions right

Nurse is vaccinating a patient amidst COVID-19 in one of the polyclinics of Aragatsotn region.
UNICEF / Arevik Grigoryan
28 December 2021

mRNA stands for messenger ribonucleic acid (mRNA) molecule that provides cells with instructions for making proteins.

The human body produces mRNA naturally and requires it in order to make vital proteins.

Unlike most vaccines containing a weakened or killed bacteria or virus, mRNA vaccines use the mRNA molecule instead of an actual bacteria or virus.

The mRNA contained in the COVID-19 vaccine provides the body with information from the COVID-19 virus, thus allowing the body to make the SARS-CoV-2 spike protein.

These proteins will then trigger the immune response, preparing the body to fight off the virus if it is affected by an actual infection.


mRNA vaccine is injected into arm muscle.

It releases mRNA into the cell. mRNA does not enter the nucleus of the cell where DNA resides. mRNA from the vaccine neither interacts with DNA nor alters it.

The mRNA will provide the cells with instructions on how to produce the spike proteins that is found on the surface of the COVID-19 virus.

The spike protein is not infectious in any way on its own.

These harmless spikes stimulate the immune system to produce protective antibodies.

If the COVID-19 virus enters the body in the future, these antibodies attach themselves to the spikes of the virus, blocking its replication.

It prevents the virus from causing the disease and protects the body.


COVID-19 mRNA vaccines are held to the same high standards for safety, effectiveness and quality as all other COVID-19 vaccines.

Though mRNA is a new way of developing vaccines, scientists have been studying and working on mRNA vaccines for decades.

It has been studied for the development of vaccines for influenza, Zika and rabies.

With the basic mRNA technology already in place, experts could quickly adapt that technology to develop vaccines aimed at COVID-19 as soon as the necessary information about the coronavirus had been gathered.


How is mRNA vaccine differs from viral vector vaccines?

mRNA vaccines use programmed and synthesized mRNA that teaches the body’s immune cells to create antibodies that can fight the COVID-19 virus.

The Pfizer- BioNTech and the Moderna COVID-19 vaccines use mRNA.

Viral vector vaccines use harmless/weakened viruses to make specific SARS-CoV-2 (COVID-19) protein and teach the body to make a protein that will trigger an immune response when the COVID-19 virus enters your body.

The Johnson & Johnson and the AstraZeneca-Oxford COVID-19 vaccines are vector vaccines.

Do mRNA vaccines change DNA?

No. The COVID-19 vaccines made with messenger RNA or mRNA do not interact with the DNA at all.

When the mRNA vaccine is introduced into the body, it engages with the cells to produce proteins.

It does not enter the nucleus – the control centre of a cell – which houses the genetic material, DNA.

Once the immune cells have used the instructions, they break down mRNA and it exits the body in a few weeks.

Are the mRNA vaccines more efficacious than the viral vector vaccines?

All COVID-19 vaccines approved by the WHO are safe and effective.

None of the COVID-19 vaccines has been directly compared in the same population and so the vaccine efficacy for the mRNA vaccines and viral vector vaccines cannot be directly compared with each other.

However, mRNA vaccines have shown a high level of efficacy across all populations - The Pfizer BioNTech vaccine against COVID-19 has an efficacy of 95% while the Moderna vaccine has shown to have an efficacy of approximately 94.1%.

Can mRNA vaccines infect a person with the COVID-19 virus?

No. mRNA vaccines do not actually contain the virus that causes COVID-19 and so they cannot infect a person with the COVID-19 virus.

After vaccination, it is not uncommon to experience body aches or low-grade fever.

These are the signs that the body is launching a protective immune response and the vaccine is doing its job.

The vast majority of COVID-19 vaccine recipients said that the side effects went away in a day or two.

Are there any contraindications to mRNA vaccines?

Although rare, it has been reported that a few people experienced anaphylaxis (allergic reaction) after getting mRNA vaccines.

If the allergic reaction occurs after the first dose of the mRNA vaccine, a second dose of the vaccine should not be administered.

In this case, you should discuss with your patient to understand which vaccine would be suitable for the second dose to complete the vaccine series.

A history of anaphylaxis to any component of the vaccine is a contraindication to vaccination.

Who can take mRNA vaccines?

The vaccine has been found to be safe and effective across all populations, including people at increased risk of severe diseases such as hypertension, diabetes, asthma, pulmonary, liver or kidney disease as well as chronic infections that are stable and controlled.

Vaccine effectiveness is expected to be similar in pregnant and lactating women as in other adults. mRNA vaccines are administered for adolescents from 12-18 years of age.

However, there have been very rare reports of myocarditis (inflammation of heart muscle) following vaccination with the mRNA vaccines.

It occurred more often among young males, aged between 12 and 29 and typically within a few days after a second dose.

The condition is usually mild to moderate and most patients who received proper medical care and treatment and were quickly recovered.

Studies are in progress to assess any further risks.

The vaccines work with the body’s natural defences to develop immunity to disease.


The decision to get vaccinated is personal choice.

Studies show that people trust their own health practitioners for information about COVID-19 and vaccines.

They want facts about the safety and effectiveness of the vaccines and understand whether vaccination is the right choice for them.

Start with empathy and understanding

"Let me know all your questions and concerns, so we can discuss about them."

Make it personal and discuss vaccination plan

"My family and I have been vaccinated safely against COVID-19.

That's the best way to return to normal life.

How about you and your family?"

Address concerns about the rapid development and new type of vaccines

"The COVID vaccines have gone through rigorous standards for safety and effectiveness as other vaccines.

When it comes to mRNA vaccines, it is a new type.

But researchers have been studying and working with mRNA for decades.

So, it is absolutely safe to take the COVID-19 mRNA vaccine."

Address misinformation

"The COVID-19 mRNA vaccines do not affect or interact with your DNA in any way, and it does not give you COVID-19".

Encourage them to take the vaccine

"This vaccine will significantly decrease your risks of getting severely ill or die.

It will give you peace of mind as it will protect you and your loved ones.

How about we book your vaccination appointment?"


The Pfizer/BioNTech and Moderna COVID-19 vaccines use messenger RNA (mRNA) to prompt the body to make an immune response against COVID-19. mRNA vaccines do not alter DNA.

The evidence says that mRNA vaccines are safe and effective and is approved by the WHO.

One common myth about mRNA vaccines is that it alters DNA.

There is a crucial difference between mRNA and DNA.

Our genetic code, DNA, is large and double-stranded while the mRNA is single- stranded and programmed to deliver instructions to parts of the cell.

DNA resides in the protected centre of the cell, the nucleus.

The mRNA from the vaccine does not enter the nucleus and never interacts with the genetic material, DNA.

There is absolutely no way that the mRNA vaccine changes DNA.

The mRNA vaccine technology has been studied for decades, including in the context of vaccines against the Zika virus, rabies and influenza. mRNA vaccines are not live viral vaccines and do not interfere with human DNA.