The Truth About Vaccines


Vaccines expose the body to a weakened form of a disease, which allows the immune system to build defenses against it. “Vaccines can prevent serious illness and death from so many diseases that used to kill hundreds of thousands of children before we had vaccines, and still continue to do so in places where they don’t have vaccines. As the diseases have become less common, we have forgotten how serious and dangerous some of these illnesses can be,” says Dr. Jasjit Singh, an infectious disease specialist at CHOC.


Some parents do not vaccinate their children, believing myths that vaccines are dangerous or cause disorders like autism. Parents also cite concerns that too many vaccines are given at once. Despite much research, there is no scientific evidence that vaccines are dangerous, cause autism or overload the immune system. Every day, a healthy baby’s immune system successfully fights off millions of germs. Antigens are parts of germs that cause the body’s immune system to go to work. “What often happens is a parent talked to a friend who planted a seed of doubt in their mind. They want to look into it further, and meanwhile hold off on vaccines. I would like to remind parents that not vaccinating and delaying vaccines is dangerous,” says Dr. Singh.

“Vaccination is an ongoing, important part of your medical care. Vaccination is a lifetime preventative medicine tool that we have,” says Dr. Singh. The Centers for Disease Control and Prevention (CDC), the American Academy of Pediatrics and the American Academy of Family Physicians all recommend that children get vaccinated against chicken pox, polio, hepatitis A and B, measles, mumps, rubella, diphtheria, tetanus, influenza (the flu), and pertussis (whooping cough), among other diseases. Adults should be vaccinated against illnesses like the flu, notes Dr. Singh, and certain vaccines are encouraged for pregnant women, especially the whooping cough and flu vaccines, she adds.

Meet Dr. Singh - Expert in Infectious Diseases

Dr. Singh is the associate director of pediatric infectious diseases and the medical director of infection prevention and epidemiology at CHOC. Her research interests include vaccines and respiratory diseases of early childhood in the developing world. Dr. Singh is dedicated to vaccine education and outreach and has lectured worldwide about vaccines and infectious disease prevention. Dr. Singh received her fellowship training at Johns Hopkins University Hospital in Baltimore and she completed her residency and internship at New York Hospital-Cornell Medical Center in New York City.

Dr. Singh’s philosophy of care: “I try to stay as up-to-date as possible with practices and information but in the end, when I am taking care of a patient, I try to care for each one as if it were my own child.”

Duke University School of Medicine, Durham, NC

Pediatric Infectious Disease

Dr. health-Singh

Dr. Jasjit Singh
CHOC Infectious Disease Specialist

“Herd Immunity” Protects Everyone Against Disease

When most people in a community are vaccinated against a disease, the virus lacks a host and will eventually go away because there are so few susceptible people left to infect. This is known as “herd immunity.”

Unless society eliminates a disease, it’s important to keep immunizing people. If the protection given by a vaccination is removed, more and more people will become infected and spread diseases to others. In time, diseases that today are almost unknown and rare in the United States, such as polio, could return.

Parents at the park with small child

CHOC Radio Podcast: Childhood Vaccinations

Dr. Antonio Arrieta

To ensure maximum protection against diseases, children should receive vaccinations at the correct, recommended age, a CHOC infectious disease specialist tells Research 360,° a podcast highlighting research at the hospital.

In this segment, Dr. Antonio Arrieta discusses proper timing of vaccinations, dispels myths surrounding vaccinations, and details his current research at CHOC. Listen in to hear more about childhood vaccinations.

How To Make Shots Less Stressful

The process of going to the pediatrician and receiving shots can be a stressful, or even anxiety-producing, for young children. Follow these simple steps on how to make shots less stressful.

Kind female nurse gives a little girl patient a vaccine

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