mRNA Technology and the COVID-19 Vaccine
May 2021
In December 2019, a novel virus in China started making headlines and health officials around the world began warning and preparing for what could be a devastating global pandemic. By March 2020, the world shut down, and panic and fear took over the lives of humans everywhere. Among many discussions, one question was the most prominent: when will we get a vaccine to protect ourselves from this virus? This was a complicated question as traditionally, vaccines take years to decades to be developed and approved, but researchers were trying something new with this one. Using mRNA technology, a COVID vaccine was able to be produced in record time and is paving the way for a new future of vaccines. However, there has been a lot of conflicting information and misunderstandings in the general public as to the safety, efficacy, and overall nature of this mRNA vaccine technology. So, let’s start with the basics:
What is mRNA?
Most people are familiar with DNA. It carries our genetic code and is essentially what makes each person unique. DNA is a double stranded molecule that carries genetic information to and from cells. In order for these cells to function properly, they need proteins. This is where RNA and mRNA come into play. RNA is a single stranded molecule complementary to DNA and is directly involved in the making of proteins for our cells. mRNA is a type of RNA which carries information to the parts of the cell that make proteins, called ribosomes, on exactly what types of proteins to make and how to make them. It may be helpful to think of the cell as a restaurant, where the ribosomes are the kitchen making proteins and the mRNA is the cookbook.
Image Credit: https://theconversation.com/coronavirus-a-new-type-of-vaccine-using-rna-could-help-defeat-covid-19-133217
How do viruses work?
Viruses cannot survive without a host as they lack the ability to reproduce on their own. If a virus is left alone for too long, it will die. But, put it inside a viable host, it will get to work to hijack their cells to turn them into virus making factories. Eventually, the cell becomes overwhelmed with the amount of viral particles it has created, and it will burst releasing thousands of new viruses into the body to continue infecting healthy cells. Normally, the immune system will recognize this and get to work to kill the virus in its tracks. Sometimes it takes a while to produce the antibodies necessary to kill them, especially if the body has never encountered the virus before and has not built up an immunity. Vaccines work to help the immune system recognize a virus before a person is infected so that if they ever do contract the real virus, they will be better prepared to fight it off. Traditionally, vaccines have been made with weakened versions of the virus in question but growing a virus in a lab is a lengthy process, which can take decades. This process introduces the viral antigen into the body without harming the host so that the immune system can start producing antibodies. But, researchers have found a way to reprogram our cells so that they make the viral antigen themselves and the immune system can start producing the antibodies without ever seeing the virus. Enter the mRNA vaccine.
Antigen: The part of a virus, usually a protein, that is capable of producing an immune response
Antibody: A protein produced within our bodies that recognizes and binds to the antigen, destroying it
mRNA Vaccine Technology
One of the biggest advantages to mRNA vaccines is that it does not require a sample of the virus, which as stated above can take years to safely grow in a lab. It only requires a genetic sequence of the virus, which technology now allows us to get fairly easily. Using this genetic sequence, it is much easier to reproduce the necessary portion of the viral mRNA for the body to produce antigens. Once this strand of mRNA is produced, it can be introduced to the body and integrated into the cells to trigger the immune response of creating antibodies. The antigen by itself is harmless but will train the immune system on how to fight off the real thing. Essentially, mRNA technology cuts out the middle man of needing the actual virus. This is how the COVID-19 vaccine was able to be produced in such record time because the longest part of the development process is no longer necessary to create an effective vaccine.
Now all this sounds great, but because of the quick development and approval and relatively unknown technology, a lot of people have been asking how do we know this is safe and why am I just now hearing about this groundbreaking technology? Well, the truth is that this technology is not actually new. Researchers have been studying mRNA and its uses in vaccines for nearly 3 decades. The biggest obstacle with this type of vaccine, is that mRNA is unstable and is rapidly broken down by the body. Injecting just the mRNA into the body would be ineffective as it would be destroyed before it could even get into the cells. Figuring out how to deliver mRNA has been the biggest challenge in creating this technology. Eventually, by the early 2010’s, researchers found that protecting the mRNA by a specialized layer of lipid, or fat, it can safely arrive at the cell and enter. Once inside, the fat is deteriorated and the mRNA can deliver its message and the cell can start making the necessary proteins to build immunity.
What are some misconceptions about the COVID-19 vaccines?
Image Credit: https://www.cnn.com/2020/12/14/us/coronavirus-vaccine-first-shot/index.html
With these technological advances, it allowed the development of the COVID-19 vaccine in record time. Just barely a year after the virus started making headlines, not one, but two vaccines were authorized by the FDA and the CDC using mRNA technology. Pfizer and Moderna’s vaccines are both about 95%
effective, meaning that in a vaccinated population, there is a 95% reduction in new cases. A vaccinated person is much less likely to contract the virus but is also much better equipped to fight it off and almost guarantees that the person will not have to be hospitalized if infected, thus reducing the strain on the medical forces. mRNA technology and its use in the development of the COVID-19 vaccine has drastically changed the healthcare landscape and will save countless lives down the road.
However, while vaccines are the biggest part on the road back to normalcy from this pandemic, we are not out of the woods yet. It is vital that those who are eligible to be vaccinated do so in order to build herd immunity and protect the general population. You can read more on general vaccines and their importance to a healthy society here.
Going forward, there are some common hesistancies and misconceptions people have about getting vaccinated:
Misconception: The vaccine was rushed through development and is not safe nor effective.
The truth: While the vaccine was produced in record time, it went through all the necessary phases and guidelines required by the FDA and the CDC to be approved. The FDA and CDC also continue to closely monitor the vaccine as more people become vaccinated for safety and efficacy.
Misconception: The vaccine will make you sick.
The truth: The vaccine contains no part of the COVID-19 virus and therefore makes it impossible to get COVID-19 from the vaccine. Common side effects may include fever, chills, aches and pains, and nausea, these are simply the result of your immune system building immunity and is completely normal.
Misconception: I only need one dose for the vaccine to be effective.
The truth: Both the Pfizer and Moderna vaccine require two doses several weeks apart to be effective. The first dose primes the immune system to recognize the virus while the second dose strengthens the immune response. Certain vaccines like Johnson & Johnson, which use a different technology, only require one dose. Make sure to check which vaccine you receive and make a follow-up appointment for the second dose if needed. Vaccines are not interchangeable.
Misconception: I already had COVID and do not need to be vaccinated.
The truth: Even if you have already recovered from COVID, the CDC recommends getting vaccinated as it is unknown how long natural immunity lasts, and it is possible to get reinfected and infect others.
As of May 2021, everyone 12 years and older are eligible to be vaccinated. Visit vaccines.gov to find a vaccination site near you.