The Proven Safety and Effectiveness of Vaccines


The Proven Safety and Effectiveness of Vaccines

Vaccinations are among the most important advances of modern medicine. In addition to eliminating diseases like smallpox and reducing other severe illnesses such as polio, vaccines have dramatically reduced the occurrence of more common illnesses like the flu and measles.

The Centers for Disease Control and Prevention (CDC) found that vaccines effectively produced immunity in 85-95 percent of patients. The chances of getting the flu after being vaccinated are reduced by nearly 60 percent while a vaccine against measles decreases the chance of illness by 98 percent.

What are Vaccines?

Today, vaccines, often called immunizations, are commonly used for preventing flu, chickenpox, measles, and more harmful diseases like Hepatitis A and B. They can be administered by a family doctor or a pharmacy.

A vaccine is a biological agent designed to build immunity against an infectious disease. They contain a weakened or killed microbe resembling that of a disease and is delivered to the body in such a way that the patient’s immune system recognizes the agent as foreign. After the agent is killed off by the immune system, the patient is said to be “immune” to the disease.

Vaccine History: Smallpox

Smallpox was once among the most highly feared and deadly diseases known to mankind. During the 18th century, it claimed the lives of 60 million people in Europe alone, and 300 to 500 million worldwide in the 20th century.

In the 1960s, the World Health Organization (WHO) launched a campaign to eradicate smallpox, focusing on immunization research and mass smallpox vaccinations. By 1979, WHO had achieved its goal through the creation of an effective vaccine, making smallpox the only disease in history to ever be fully eradicated.

The Health Concerns of Vaccines

Despite the proven effectiveness of vaccines, many people are concerned about their safety and side effects. The Internet is full of rumors and stories of vaccines leading to brain damage or autism, or even causing the disease they are supposed to prevent.

Additionally, many blogs and forums discuss concerns over the use of mercury as a vaccine preservative, blaming it for many health side effects. These concerns are not without merit, yet many of the facts have been skewed or ignored by critics. Some of the latest research effectively refutes these claims.

Are Vaccines Linked to Autism?

One of the most serious accusations against vaccine safety is that it is linked to autism in children. Much of the debate on this issue can be traced to a study published in 1998 by Andrew Wakefield, a former British surgeon. The study claimed that there was a link between the administration of the measles, mumps, and rubella (MMR) vaccine and acquired autism in children. Many researchers attempted to duplicate Wakefield’s results, all without success.

In 2010, the British General Medical council conducted an investigation that found the study to be fraudulent, hinting at financial conflicts of interest on Wakefield’s part and confirming 36 other incidents of fraud within the study.

More recent research from the CDC, the Journal of the American Medical Association, the Institute of Medicine, and the World Health Organization confirms that there is no link between the MMR vaccine and autism or any other major health issue. Many people, however, still cite the autism issue as a major concern when debating the safety of vaccines.

Vaccines do not Contain Elemental Mercury

There are also major concerns about vaccines containing mercury or aluminum preservatives. First, it is worth noting that mercury was removed from all vaccines except the flu vaccine in 1999. Not all flu shots contain mercury, though, and many doctors give their patients the option of choosing flu shots without mercury.

Second, the mercury (known as thimerosal) once contained in vaccines is considered safe. The CDC states that, “there is no convincing evidence of harm caused by the low doses of thimerosal in vaccines, except for minor reactions like redness and swelling at the injection site.”

Vaccines Containing Aluminum

Aluminum has also been a source of concern due to its use in various vaccines. Aluminum causes a person’s immune system to respond more aggressively to vaccines. It is the only safe element known to produce this effect.

While aluminum can be toxic in large doses, the amount present in vaccines is miniscule, and most of it is immediately eliminated by the body. Many critics are also not aware that aluminum is not used in the most common vaccines like flu shots, MMR, and chickenpox.


Vaccination has a solid track record of success, both for preventing many infectious diseases and eradicating smallpox. The most effective time to administer vaccines is within a year of a baby’s birth, since that is when they are most susceptible to infectious diseases.

However, there are vaccines for people of all ages, which is why our Western Washington Family Practice groups provide immunizations for your whole family. Request an appointment today with one of our family medicine providers.