This commentary is by Melissa Volansky, M.D., chief medical officer of Lamoille Health Partners.
As a physician at Stowe Family Practice, I hear many patients express fear about receiving one of the authorized Covid-19 vaccines. People wonder how the vaccine works. Is it safe? Was the approval process rushed? What is a nanoparticle?
A nanoparticle is not a nanite! Nanites are tiny robots being developed to help with molecular scale problems. The nanoparticle in the PfizerBioNTech and Moderna vaccines is completely different.
The vaccine is called a nanoparticle because of its size. “Nano” means that the size of the particle is about a billionth of a meter, which is extremely small. The particle consists of a piece of messenger RNA (mRNA) that serves as a recipe for the Covid-19 spike protein, sandwiched between two layers of lipid molecules. There are no robotics involved.
The lipid bilayer resembles our own cell membranes, enabling the nanoparticle to fuse with our cells and deliver the mRNA. Once inside the cell, the mRNA is used to produce many copies of the Covid-19 spike protein, which go out to the cell surface to be shown to the immune system. Once the mRNA has done its job, it is rapidly degraded. The mRNA never goes to the cell’s nucleus, and never mixes with the cell’s DNA.
Sentry cells from the immune system see the spike protein on the outside of the cell as foreign. They ingest the foreign protein and carry it to the lymph nodes. Once there, more immune cells learn to recognize the spike protein and produce antibody- and cytokine-producing cells that can rapidly destroy any coronavirus they encounter in the future, thus preventing coronavirus infection.
Cells use mRNA to make proteins they need to respond rapidly to changes in the environment. Thus, mRNA is not built to last. Cells routinely break down mRNA to make way for new mRNA. This makes mRNA vaccines hard to store. Unless perfect conditions are maintained, the vaccines can degrade rapidly. But, given the short-lived nature of these vaccines, you would expect them to be very safe and, in fact, this seems to be the case.
While mild side effects often occur after vaccination, serious problems are extremely rare. During the testing phase, Pfizer BioNTech and Moderna vaccines were given to about 37,000 subjects with no serious adverse events. Once the vaccine started to be given to the public, a few people had serious allergic reactions. Everyone is now being watched after they receive their shot, even though such reactions happened in only one out of every 100,000 people. For comparison, reactions to penicillin occur 20 times more often, in one out of every 5,000 recipients.
These vaccines are over 90% effective in preventing symptomatic Covid-19 infection. Among those 37,000 people who received the vaccine in the trials, only one serious case of Covid-19 infection occurred.
Operation Warp Speed brought us two Covid-19 vaccines in just eight months, which is an accomplishment on par with the Apollo space missions or the Manhattan Project. This is our generation’s moon launch! How did they do this so quickly?
This was a highly coordinated global program partnering government and private entities in a race to achieve a very specific goal. The program narrowed its focus to four different vaccine mechanisms thought likely to be successful. Efforts were funded immediately. Rather than guarding proprietary secrets, teams collaborated and shared information.
All the traditional steps for testing safety and efficacy were conducted. To be more agile, those steps were performed in parallel instead of sequentially, and manufacturing of the vaccine was started at the same time. This way, vaccines that received approval could be available immediately. At a cost of $18 billion, two vaccines were authorized in just eight months, and two more vaccines are expected to be authorized soon.
These vaccines will save lives. If enough people are vaccinated, we can reopen schools and businesses to resume normal society. The immunity provided by the vaccines may last longer than that from natural infection. There are very few medical reasons a person cannot receive the vaccine. If you have questions, please contact your primary care provider. We want to address your concerns so you can make the right decision for you and your family.
References:
https://www.cdc.gov/vaccines/covid-19/index.html
https://www.nejm.org/covid-vaccine
https://www.nejm.org/doi/full/10.1056/NEJMoa2034577
