Preventing Infectious Disease With Immunizations

Immunizations make a vast contribution to global health. According to the World Health Organization, vaccines prevented at least 10 million deaths between 2010 and 2015. Dr. Stephen Threlkeld, infectious disease consultant and epidemiologist for the Baptist Heart Transplant program, discusses what you need to know about vaccinations, including why vaccines are safe and when to get them.

Who do vaccines help protect?

“Vaccines protect us all,” said Threlkeld. “While we’re used to thinking of vaccines as protection for children, they protect adults from serious illness, too. They prevent you from transmitting an infectious disease to other people—particularly people who might have weak immune systems, such as infants, people with vaccine allergies and people with an immune-suppressing disease.”

Immunizations typically start in infancy. Early childhood vaccinations are one of the best ways to protect children and others from life-threatening diseases. Children who do not finish the recommended number of vaccine doses or do not receive immunizations face serious risks.

For example, in 2017 the Centers for Disease Control and Prevention documented the first reported case of a child contracting tetanus in Oregon in more than 30 years. The case involved an unvaccinated 6-year-old boy who cut his forehead while playing outside. As a result, this child spent 57 days in the hospital, could not open his mouth and developed severe muscle spasms and hypertension.

Thanks to vaccinations, cases like this are rare.

When should people get vaccines?

The need for vaccines varies throughout a person’s life. Dr. Threlkeld suggests parents and adults consult their doctors for a vaccination schedule, or visit CDC’s website for a list of vaccines organized by age and population or condition. The site includes vaccine schedules for infants and children, adults, health care workers, travelers, pregnant women and others.

How do people with weak immune systems benefit from others’ immunity?

“Herd immunity is a term used to describe indirect protection from infectious diseases,” said Threlkeld. “It occurs when a large percentage of a population is immunized.”

Herd immunity makes it difficult for certain infectious diseases to spread from one person to another and provides a level of protection for adults and children who are not immune.

“The more vaccinated people you have around a person with a poorly functioning immune system, the more protected they are going to be,” said Threlkeld. “However, when parents don’t vaccinate their children, we lose some of that herd immunity. An unvaccinated child is a risk to themselves and others. When people aren’t protected, more people are potentially exposed to infectious diseases.”

Are vaccines safe?

Vaccines are rigorously tested and evaluated in safety trials for years before receiving approval for infants, children and adults. The Food and Drug Administration licenses vaccines for public use only if they are safe and effective.

“When you look at the measles vaccine and the fear of autism, those data have been extensively studied,” said Threlkeld. “There is no link between autism and vaccines. Many parents are afraid because the age at which children receive vaccinations is the age at which some children show signs of autism. It’s natural for parents to look for a link. However, it’s been extensively studied and there’s no evidence that vaccines cause autism.”

Serious side effects from vaccines are extremely rare. For example, vaccine allergies may occur in 1 or 2 people out of 1 million doses of a vaccine. Common vaccine side effects include fever, shivering, headache and muscle or joint pain.

“If you compare these side effects to the enormous protection that vaccines afford you, your family and the community, it’s a statistical no brainer,” said Threlkeld. “Immunizations are designed to protect us.”

Learn more about the importance of vaccination, or find a doctor by visiting our Find a Doctor page.