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How Do COVID-19 Vaccines Work?

 

As of May 28, 2021, the CDC has recommended that fully vaccinated people resume their normal activities without wearing a mask or physical distancing. This draws from more individuals getting inoculated across the country, which reduces the chances of infection from fully vaccinated individuals to those who are unvaccinated. Other states are following suit with fewer statewide orders on mask mandates. While this may bring us closer to the life we knew before the pandemic, other areas are still exercising caution. Connecticut is still requiring indoor mask-wearing for people over 2 years old. Hawaii only lifted the outdoor mask-wearing last May 25 but residents 5 years and older still need to wear a face-covering indoors and businesses can refuse admission to mask-less visitors.  

Only 42.6% of the total US population has been fully vaccinated. For the country to achieve herd immunity and thrive while we return to normal, Dr. Fauci estimates it may take 90% of the population to be vaccinated. The larger estimate emphasizes how much longer it may take before cases lower significantly. Unfortunately, a poll found that despite lower vaccine hesitancy, many working-age adults are more unsure about getting their shot more than older individuals. Side effects are their primary concern, while about one-third think they don’t need the vaccination. Others don’t trust the COVID-19 vaccine, while some respondents said they’d prefer to see if the available shots are safe. These sentiments may stem from the misinformation on COVID-19 vaccines we see online. To prevent the spread of fake news, businesses can do their part in sharing fact-checked, accurate information that encourages their employees to receive complete COVID-19 vaccine doses. If you need an easy reference to share, print, and show in your establishment, check out the fact lists and summaries below. We hope the science-based information and benefits listed will encourage your staff and customers to get us closer to achieving herd immunity.  

Vaccine Primer: Pfizer-BioNTech, Moderna, and Johnson & Johnson 

 

Pfizer-BioNTech 

Moderna 

Johnson & Johnson 

 How do they work? 

mRNA that carries a section of the COVID-19’s genetic code 

Encases the genetic sequence of COVID-19 inside a harmless adenovirus 

 

 Number of Doses 

2 

1 

 Side Effects 

Pain on the injection site, fatigue, chills, body aches, headaches, and fever.  

 Storage requirements  

-94oF for up to 6 months 

-4oF for up to 6 months 

36-46oF for up to 6 months 

 Effectivity 

95% 

95%  

72% 

 

 

 

 

 

 

 

 

 

 

 

Coronavirus Explained 

Before we get into how each vaccine works, it’s important to know what the SARS-CoV-2 virus is like. The virus’s surface is studded with spike proteins that latch onto the human’s body cell and cause the infection. The vaccines can identify and destroy these spike proteins. Here’s how the different vaccine platforms do this:  

 

mRNA Vaccines Explained 

The Pfizer-BioNTech and Moderna vaccines use the messenger (mRNA) platform to familiarize your body with the COVID-19 virus and build the necessary defenses against it. 

                        1. If mRNA is injected into your body, our natural enzymes will end up degrading it. Pfizer-BioNTech and Modern protect the mRNA in lipid nanoparticles to prevent this from happening. 
                        2. The vaccine particles collide and fuse into your cells to release the encased mRNA. The cell will read the mRNA’s sequence and start building spike proteins based on this. Your cell destroys the mRNA, so in no way does it get to your DNA and alter it.  
                        3. The formed spike proteins move to the vaccinated cell’s surface. Some of the proteins are broken into fragments through the vaccinated cells. The coronavirus spike proteins and their fragments alert your immune system.  
                        4. The immune system uses the following cells to identify and attach the spike protein fragments latching onto vaccinated cells and any coronavirus-infected cells: 
                        5. The antigen-presenting cell takes up the debris with the coronavirus spike proteins and protein fragments. The debris comes from a dead vaccinated cell. 
                        6. The helper T cells recognize the spike proteins from a vaccinated cell and inform other immune cells about the infection.  
                        7. Immune cells called the B cells to bump into the vaccinated cells or floating spike proteins. Thanks to their activation from the helper T cells, the B cells proliferate and start targeting the spike proteins with antibodies. 
                        8. The produced antibodies lock onto the coronavirus spike proteins and destroy them before they can infect other cells. 
                        9. Another immune cell, the killer T-cell, goes out to destroy the spike protein fragments that have latched onto any coronavirus-infected cells.  

 

Viral Vector Vaccines Explained: Johnson & Johnson’s Janssen COVID-19 Vaccine  

                        1. The Johnson & Johnson COVID-19 vaccine uses the modified version of the adenovirus 26, which is commonly known to cause flu or colds. The modification ensures that your body won’t develop flu or colds.  
                        2. Material from the virus-causing COVID-19 is found within the modified adenovirus.  
                        3. After you’ve received the shot, the adenoviruses begin colliding into your cells. Once your cell absorbs the adenovirus in a bubble, the adenovirus will escape this bubble and move to the nucleus. 
                        4. The nucleus is where your DNA is stored. The adenovirus will inject the DNA inside the cell nucleus. Your cell will read the gene for the coronavirus spike protein and copy it onto the messenger RNA or mRNA.  
                        5. As its name implies, the mRNA carries a message or sequence that your cell will read. This message is read when the mRNA leaves the nucleus, which initiates the assembly of spike proteins.  
                        6. From here, your immune system will build the necessary defenses and offenses against the COVID-19 virus. The virus’s spike proteins will start sticking out to trigger a response in your immune system. At the same time, the adenovirus also sends an alarm to activate any nearby immune cells. 
                        7. The immune system uses three cells to identify and attach the spike protein fragments latching onto vaccinated cells and any coronavirus-infected cells: 
                        8. The antigen-presenting cell takes up the debris with the coronavirus spike proteins and protein fragments. The debris comes from a dead vaccinated cell. 
                        9. The helper T cells recognize the spike proteins from a vaccinated cell and inform other immune cells about the infection.  
                        10. Immune cells called the B cells to bump into the vaccinated cells or floating spike proteins. Thanks to their activation from the helper T cells, the B cells proliferate and start targeting the spike proteins with antibodies. 
                        11. The produced antibodies lock onto the coronavirus spike proteins and destroy them before they can infect other cells. 
                        12. Another immune cell, the killer T-cell, goes out to destroy the spike protein fragments that have latched onto any coronavirus-infected cells.  

 

The Facts on COVID-19 mRNA Vaccines 

    • These vaccines do NOT use a live virus that will cause COVID-19.  
    • The mRNA is used to transfer a message or the sequence about the virus. The cell destroys the mRNA once it’s read the message, so it will not alter your DNA. 
    • Your DNA is kept inside the nucleus of the cell. The mRNA is destroyed before it will reach this area. 
    • More evidence is showing that the “mRNA COVID-19 vaccines provide similar protection in real-life conditions as they have in-clinic trial settings,” as the CDC reports. In other words, the more people are vaccinated with Pfizer or Moderna, then we greatly reduce most individuals’ risk of contracting COVID-19 by 90 percent or more. 
    • Like other vaccines, there is still a chance that fully vaccinated individuals will get sick. But data suggests the symptoms of those with COVID-19 experience less severe symptoms, thus lowering their chances of getting hospitalized. 

 

The Facts on the Johnson & Johnson Janssen Viral Vector Vaccine 

    • These vaccines use the vector of another type of harmless virus to produce a harmless version of the one that causes COVID-19. The produced virus will not infect you with COVID-19 or the vector’s virus. 
    • The viral vectors are altered genetically so as not to cause disease in your body. The genetic material they deliver will NOT change your DNA. 
    •  Johnson & Johnson’s Janssen COVID-19 vaccine is recommended and safe for all individuals aged 18 years and older.  
    • While women younger than 50 years old may have a risk of blood clots with low platelets after vaccination, this is a rare and serious adverse event that occurs in about 7 per 1 million vaccinated women. The event is even more rare among women 50 years and older.  
    • The CDC and FDA reviewed all the available data to ensure that the benefits of the Janssen COVID-19 vaccine outweigh the risks of those who can receive it. For more information on the previous pause and resume of its use, check out this FAQ from the CDC.  

 

The Truth About Side Effects in COVID-19 Vaccines 

    • Your body will experience normal side effects. These are signs that the body is building protection against COVID-19. 
    • Side effects normally last between 2 to 3 days. You can resume normal activities after this period.  
    • Other people don’t experience side effects at all. It depends on the individual. 
    • Common side effects on the arm where you got injected are pain, swelling, and redness. 
    • Common side effects for the rest of the body are:  
    • Chills 
    • Fever 
    • Nausea 
    • Tiredness
    • Headache
    • Muscle pain 

If you need an easy reference, download the CDC fact sheet on what to expect after getting a COVID-19 vaccine. It includes precautions you can take and what to do in the event they last longer than usual.

 

cdc vaccine fact sheet

 

 

COVID-19 Vaccine FAQs  

Can my kids receive a COVID-19 vaccine? 

Yes, children 12 years and older can get vaccinated against COVID-19.  Your kids may experience side effects like adults but it will only last a few days. Your child receiving the vaccine will protect your child, your family, and other individuals from the virus. 

Can a pregnant woman receive the vaccine? 

Yes, pregnant women can take the COVID-19 vaccine. The CDC recommends pregnant women talk to their healthcare provider prior to help them in their vaccination decision.  

Will the COVID-19 vaccine change my DNA? 

No, none of the COVID-19 vaccines will interact or alter your DNA. Both vaccine platforms deliver genetic materials that instruct the cells on how to protect our bodies against COVID-19. These materials do not enter the cell’s nucleus, where our DNA is located. The vaccine ensures that there is no opportunity for the vaccine to interact with your DNA.  

Can the COVID-19 vaccine infect me with the COVID-19? 

No, none of the authorized vaccines or the ones in development contain live viruses that cause COVID-19. In other words, it cannot infect or make you sick with the coronavirus. 

Will the COVID-19 vaccine make my body magnetic?  

No, COVID-19 vaccines do not contain any ingredients that generate an electromagnetic field on the injection site. They are free of metals such as cobalt, lithium, iron, nickel, and other manufactured metals like electrodes and microelectronics. It should also be noted that one dose is less than a milliliter, an amount that isn’t even enough for magnets to be drawn onto your arm.  

Are the COVID-19 vaccines available safe and effective?  

Yes, all three COVID-19 vaccines that have been authorized have been tested and found to be safe and effective in preventing severe COVID-19, according to John Hopkins Medicine 

Do individuals who’ve recovered from COVID-19 still need to get vaccinated? 

Yes, you need to get vaccinated even if you have recovered from COVID-19. Experts are still studying how long one is protected from reinfection after the recovery. Unvaccinated individuals who have recovered from the COVID-19 virus still have a rare chance of being infected again.  

I had a severe allergic reaction on the first dose, should I continue with the second? 

No, if you have a severe or immediate reaction to the first dose, you should not get the second dose or a similar vaccine platform. This means that if you had an allergic reaction to Pfizer, you cannot get Moderna. Likewise, if you have an allergic reaction to the J&J/Janssen vaccine, you cannot receive similar viral vector vaccines. 

For those who had an allergic reaction to their first mRNA vaccine, it’s best to consult your doctor about getting another type of COVID-19 vaccine.  

For more information on allergic reactions to COVID-19 vaccines, check out this page from the CDC. 

 

Article Sources and Reading References:  

CDC: Understanding mRNA COVID-19 Vaccines  

CDC: COVID-19 Vaccines Work   

New York Times: How the Pfizer-BioNTech Vaccine Works 

New York Times: How Moderna’s Vaccine Works 

New York Times: How the Johnson & Johnson Vaccine Works 

New York Times: The Coronavirus Unveiled  

CDC Recommends Use of Johnson & Johnson’s Janssen COVID-19 Vaccine Resume