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Vaccines: The Myths and the Facts

Vaccines: The Myths and the FactsFact: Vaccines are an effective means of preventing life-threatening illnesses by boosting the body’s natural immune response to diseases caused by viruses and bacteria. Vaccine programs throughout the world have led to improved overall health of our population by reducing the transmission of disease, permanent and temporary disability, and infant mortality. Although vaccines have been proven to be both safe and effective based on sound scientific evidence, several myths have been spread, keeping vaccines at the center of controversy. The COVID-19 pandemic has caused significant illness and disease for the world’s population. With the approval of vaccinations against SARS-CoV-2 to prevent COVID-19 illness, there are also myths that are circulating about the production, effectiveness and risks of these vaccines. Here we provide the top five general vaccine myths and the top five COVID-19 vaccine myths in an effort to emphasize the safety and necessity of this important healthcare intervention.  

Myth 1: Vaccines contain many harmful ingredients.
Vaccines contain ingredients that allow the product to be safely administered. Any substance can be harmful in significantly high doses, even water. Vaccines contain ingredients at a dose that is even lower than the dose we are naturally exposed to in our environment. Thimerosal, a mercury-containing compound, is a widely-used preservative for vaccines that are manufactured in multi-dose vials. We are naturally exposed to mercury in milk, seafood, and contact lens solutions. There is no evidence to suggest that the amount of thimerosal used in vaccines poses a health risk. Many vaccines are now produced in single-dose vials, which has greatly decreased the use of thimerosal in vaccine production. Formaldehyde, another vaccine ingredient, is in automobile exhaust, household products and furnishings, such as carpets, upholstery, cosmetics, paint and felt-tip markers, and in health products, such as antihistamines, cough drops and mouthwash. The dose in vaccines is much lower than the amount we are exposed to in our daily life. Another example of an ingredient in vaccines is aluminum, which is added in order to boost and build a stronger immunity to the vaccine. Not all vaccines contain aluminum, but those that do typically contain aluminum in amounts that is much less than what the average person consumes in a day from foods, drinking water and medicines.

Myth 2: Vaccines cause autism and sudden infant death syndrome (SIDS).
Vaccines are very safe. Most vaccine reactions are usually temporary and minor, such as a fever or sore arm. It is rare to experience a very serious health event following a vaccination, but these events are carefully monitored and investigated. You are far more likely to be seriously injured by a vaccine-preventable disease than by a vaccine. For example, polio can cause paralysis, measles can cause encephalitis (inflammation of the brain) and blindness, and some vaccine-preventable diseases can even result in death. The benefits of vaccination greatly outweigh the risk, and without vaccines many more injuries and deaths would occur. Science has not yet determined the cause of autism and SIDS. These diagnoses are made, though, during the same age range that children are receiving their routine immunizations. The 1998 study that raised concerns about a possible link between measles-mumps-rubella (MMR) vaccine and autism was retracted by the journal that published it because it was significantly flawed by bad science. There is no evidence to link vaccines as the cause of autism or SIDS.

Myth 3: Vaccine-preventable diseases are just part of childhood. It is better to have the disease than become immune through vaccines.
Vaccine-preventable diseases have many serious complications that can be avoided through immunization. For example, more than 226,000 people are hospitalized from influenza complications including 20,000 children. About 36,000 people die from influenza each year. Vaccines stimulate the immune system to produce an immune response similar to natural infection, but they do not cause the disease or put the immunized person at risk of its potential complications.

Myth 4: I don’t need to vaccinate my child because all the other children around them are already immune.
Herd immunity occurs when a large portion of a community is immunized against a contagious disease, reducing the chance of an outbreak. Infants, pregnant women and immunocompromised people who cannot receive vaccines depend on this type of protection. However, if enough people rely on herd immunity as the method of preventing infection from vaccine-preventable diseases, herd immunity will soon disappear.

Myth 5: A child can actually get the disease from a vaccine.
A vaccine causing complete disease would be extremely unlikely. Most vaccines are inactivated (killed) vaccines, which makes it impossible to contract the disease from the vaccine. A few vaccines contain live organisms, and when vaccinated with live vaccines, it may lead to a mild case of the disease. Chickenpox vaccine, for example, can cause a child to develop a mild rash. This isn’t harmful, and can actually show that the vaccine is working. One exception was the live oral polio vaccine, which could very rarely mutate and actually cause a case of polio. However, the oral polio vaccine is no longer administered in the United States.

Myth 6: The COVID-19 vaccines were not tested before approval.
There are basically two aspects to vaccine testing. The first test is whether or not the vaccine is safe. The second test is how effective the vaccine is at preventing disease or preventing a severe course of the disease. Many people were surprised and suspicious as to how fast vaccines for COVID-19 were developed. However, the world scientific community has had many years of experience in the development and testing of many kinds of vaccines, including those for previous coronaviruses similar to the one that causes COVID-19. Therefore, scientists had a very good idea where to begin regarding the development of the various COVID-19 vaccines currently available and even those still undergoing testing. The relatively rapid development of vaccines was no surprise to the experts in the field. All COVID-19 vaccines currently available in the United States have been thoroughly tested for safety and how effective they are at preventing disease.

Testing the safety of a vaccine is a complicated process, much of which happens well before the first person is injected. It is first tested in laboratories in tissue culture and animals (in a very humane way). Once the vaccine has been proven safe in animals, the researchers then start vaccinating human beings.  During this stage, the researchers examine how effective the vaccine is at prevention of the disease. The participants are also closely monitored for any side effects- this includes ANYTHING that happens to them from allergic reactions to tripping on a rug. Human trials are done in 3 phases. During phase 3, thousands of volunteers are tested. Once the vaccine is proven to be effective to prevent the disease and associated with none or only minor side effects, it is then approved for vaccinating larger groups of people. Side effects are monitored during all phases of testing and even after approval for the vaccine is obtained. You can obtain additional information on the vaccine development process here.

Myth 7: You can get COVID-19 from the vaccine.
We know that no vaccine is 100% effective. While all of the currently approved COVID-19 vaccines have shown effectiveness at preventing the disease, full effect and protection will take time after the vaccine is given. During this time, the body develops proteins called antibodies, which provide immunity against future infection. Exposure to the SARS-CoV-2 virus which causes COVID-19 disease prior to vaccination or during the time where full immunity has not been reached, may mean that you develop the disease and may experience symptoms of COVID-19. All of the current COVID-19 vaccines approved for use in the United States do not contain the live virus, which means you cannot contract COVID-19 from these vaccines.  

Myth 8: There are microchips in the COVID-19 vaccine.
There are no microchips in the COVID-19 vaccines currently on the market or currently being investigated. The vaccines are not tracking people or gathering their information in any way, shape or form.

Myth 9: COVID-19 vaccines will alter my DNA.
The first two COVID-19 vaccines approved in the United States were mRNA vaccines (Moderna and Pfizer). The mRNA that is used in these vaccines is a template for making virus proteins that then stimulate the body’s immune system to produce antibodies that will lead to immunity to the virus. mRNA is rapidly degraded and is not integrated into the individual’s own DNA, so it will not alter the genetic code of the individual.

Myth 10: Since I already had COVID-19 and recovered, I do not need to be vaccinated.
There is not enough information available to determine how long immunity against the SARS-CoV-2 virus will last after recovering from the infection. Studies are ongoing to determine how long natural immunity lasts, however, there is some evidence that immunity may not last long. The Centers for Disease Control and Prevention (CDC) currently recommends that you receive a COVID-19 vaccine when you are eligible regardless of whether you already had COVID-19 disease. You should schedule your vaccine after quarantine or isolation time is complete. For patients who received monoclonal antibodies or convalescent plasma to treat COVID-19 disease, you should wait 90 days before getting the vaccine.

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