Why Vaccination Is Safe

Knowing more about the testing and approval processes can help you understand how safe they actually are.

There is so much information about vaccines in the media. But is all of the information true? Some sources tend to steer their readers away from vaccines, despite the fact that they are crucial to healthy living. Distinguishing myths from facts will aid you and your family. Take a look at some of the facts about vaccines that will help you understand why vaccines are safe and beneficial to health.

Vaccine Ingredients

Have you ever wondered what the active ingredient in a vaccine is made of? Well to answer that question, you would need to know the two different types of vaccines: live vaccines and non-live vaccines.

Live vaccines

Live vaccines are made of viruses or bacteria that are not killed. They are simply weakened. The live vaccine replicates in the recipient’s body and creates an immune response to the disease similar to a natural infection. Those with weakened immune systems should ask a doctor before taking a live vaccine. For people with strong immune systems, it gives long-term protection against disease.

Non-live vaccine

A non-live vaccine contains bacteria or viruses that have been killed. These vaccines do not replicate and can be given to people with weakened immune systems. The immune system produces antibodies in response to a non-live vaccine. However, because these vaccines do not contain live bacteria or viruses, they do not provide long-term protection and require multiple doses over time.

Side Effects

As mentioned above, medical professionals and scientists test the vaccine for side effects during clinical trials. Most people have only mild side effects, or none, after vaccination. Side effects can include fever, fatigue, and body aches. It is also common for the vaccinated area to become a little swollen and tender where the needle passes through the skin. Typically, these mild side effects do not last long and go away on their own after a day or two.

Allergic Reactions

Some people may have allergic reactions to the ingredients in a vaccine. Although allergic reactions only impact a small number of people, they can be serious. This is why you might have been asked to wait for a 15-minute observation period after receiving a vaccine. This time allows healthcare professionals to keep an eye on you and respond quickly in the rare event you show signs or symptoms of an allergic reaction.

People with known allergies to a vaccine’s ingredients should speak with their doctor about their individual risks, benefits, and other options for protecting themselves.

Testing and Approval

A lot of time and research goes into vaccines before they are released to the public. Even with advances in technology that have shortened the process, it takes years to develop a vaccine and to conduct and evaluate clinical trials. This is true for the COVID-19 vaccines, too: development of vaccines against related SARS viruses had been underway long before the SARS-CoV-2 virus emerged in 2019.

Vaccines undergo rigorous testing. Trained scientists and medical professionals conduct clinical trials in three phases. The first phase tests the vaccine on a small group of people. Scientists observe the safety, dosage, and side effects in this group. Next, the scientists test their vaccine on a second group consisting of hundreds of volunteers. This group is monitored for short-term side effects and how strongly the immune system responds. Finally, the third phase of clinical trials compares thousands of volunteers who are given the vaccine to thousands of other volunteers who have not received the vaccine.

The vaccine is still not ready to be released to the public. After the clinical trials, an independent group of medical professionals evaluates the results. If approved, the vaccine gets to be added to the US Recommended Immunization Schedule.

In the case of an emergency outbreak, there is also an Emergency Use Authorization (or EUA) process in place. This authorization allows the federal Food and Drug Administration (FDA) to approve the use of a vaccine sooner than is possible under the normally paced approval process. The EUA gets doses to the public faster by allowing manufacturers to make millions of doses while clinical trials are still underway. The EUA process does not shorten or skip clinical trials. So, even though the process of rolling out the vaccine is faster, the vaccine still undergoes the same clinical trials and safety evaluations required by the normal process.

Herd Immunity

Herd immunity is just what the phrase suggests: it is when so many people in the community, or “herd”, have been vaccinated that the virus has a hard time spreading to new hosts. When the chain of person-to-person transmission gets broken this way, the outbreak winds down and can even stop entirely. Herd immunity can only be achieved if everyone who can get vaccinated, does gets vaccinated. This also protects people who are not able to receive vaccinations due to medical reasons. So, by getting your vaccination, you are not only protecting yourself but also your family and the community around you.

In addition, if enough people get vaccinated, some diseases can be greatly reduced or even completely eliminated. For example, smallpox was once one of the world's deadliest diseases, killing millions of people each year. Through intense national and global vaccination efforts in the 1950s and 60s, enough people were vaccinated to completely eradicate the disease.

Bottom line

Vaccination is incredibly safe and effective. Vaccines have made many diseases that once killed or disabled millions of people into diseases so rare many people have never heard of them. Talk to your doctor about which vaccines you and your loved ones need, and ask about any concerns you may have. Then, roll up your sleeve and help protect yourself, your family, and your community against a deadly foe.

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The content of this blog was reviewed and approved by Jason Smith, MD, Chief Medical Officer, St. Mary’s Health Care System.