Thursday, February 26 2015 3:21

Keeping the Faith in Vaccines

Written by Dr. Kristen A. Feemster, CHOP

The recent measles outbreak brings this issue back in the spotlight.

With our current immunization schedule, kids get 24 injections against 14 different diseases before they’re 2 years old—sometimes involving 5 injections in one visit. At a time when many vaccine-preventable diseases are rarely seen, this schedule may give some parents pause. Is it safe to give so many injections to young children? If no one gets these diseases anymore, are vaccines necessary? Are there other ways to protect our kids?

All excellent questions. As a pediatrician, I view immunizations as one of the most important public health interventions of our time. Unfortunately, vaccines may be a victim of their own success since most parents have never seen a case of measles, mumps, whooping cough or bacterial meningitis.

When the risk of these diseases feels distant, concerns about vaccine safety rise, making delaying or refusing vaccination seem a prudent decision to protect our children’s health. However, as the recent measles outbreak shows us, vaccines continue to be needed.

The Diseases Are Still Here

The risk of vaccine-preventable diseases still exists. Measles recently struck over a hundred people throughout the country after an outbreak at Disneyland. And, we’ve had more cases of whooping cough in the U.S. over the past few years than over the past 50 years.

A reason for these outbreaks is that the barriers created by vaccination are eroding as more parents delay or refuse vaccination. We also live in a global society, so diseases, like people, can travel. Given recent events, it’s important to know what the choice of not vaccinating can mean, not only for our children, but for our neighbors.

Protecting Ourselves and Our Neighbors

Vaccines work in two ways: they protect you from getting infected and from spreading the infection to others—if a virus or bacteria can’t get to me, I can’t spread it to you, which is especially important for those who are unable to be vaccinated because of age or a compromised immune system. That dual effect—or herd immunity— is why vaccines have had such a significant impact on eliminating certain childhood diseases. Vaccinating kids protects adults, too.

The current vaccination schedule is based on years of safety and effectiveness data, plus research about each disease. Vaccines are recommended at certain ages to ensure a good immune response and protection when children are most vulnerable to vaccine-preventable diseases.

Easily Spread and Serious Infections

For example, pertussis, or whooping cough, is a bacterial respiratory infection that can cause a prolonged, persistent cough in older children and even adults. In infants, it causes a severe cough that affects breathing—most infants with pertussis are hospitalized and one in 100 die. Measles is a febrile viral illness with a rash that may self-resolve. However, serious illness also occurs, even in healthy children, including pneumonia or swelling of the brain. And one in 1,000 infected children die.

Both measles and pertussis start out with runny nose and mild cough, resembling the common cold. Unfortunately, the risk of transmission is highest during this time, so you can spread infection before you know you’re sick. Pertussis and measles are also two of the most contagious infections, with 9 out of 10 susceptible people (no immunity from vaccination or history of previous infection) exposed becoming infected. These consequences make vaccination especially important to prevent infection.

Teen Vaccines

Vaccination is also important for adolescents, who should get TdaP (tetanus, diphtheria and pertussis), MCV4 (meningococcal conjugate) and Human PapillomaVirus vaccines (HPV). Teens are better able to fight off many infections that affected them as children, but their risks change over time. These additional vaccines help adolescents protect their health as they transition to adulthood.

Some parents have questions about HPV vaccines, the most recent addition for adolescents. HPV is the most common sexually transmitted infection (almost everyone has been infected by adulthood). While many of us can fight off infection, some will develop persistent infection that can lead to a wide range of cancers, including cervical cancer. That makes the HPV vaccine one of the only cancer-prevention vaccines we have—and it’s extremely effective.

Why give the HPV vaccine to teens? It’s important to be vaccinated before exposure and the vaccine is especially effective in young adolescents. Despite some news stories, this vaccine is very safe. Fainting is the most significant side effect, but this can happen after any vaccine.

Safety First

Vaccine safety is constantly monitored and extensively reviewed. Side effects can occur, but they’re generally mild—fever, arm pain and swelling. Serious adverse reactions like anaphylaxis are extremely rare (one in a million). Many parents worry about long-term side effects.

The Institute of Medicine (IOM), a nonprofit, independent, non-governmental research organization, recently conducted a review concluding that the current vaccine schedule is safe and doesn’t increase risks for autoimmune diseases, asthma, seizures, developmental disorders including autism, hypersensitivity or attention deficit disorders.

We’re fortunate to live in a world where we no longer worry about many vaccine-preventable diseases. But we can’t let our guards down. As a pediatrician and parent, I consider recommending—and accepting—immunizations as one of the most important things I can do to support the health of my patients, my children and my community.

The recommended immunization sche-dule was developed by scientists, epidemiologists and health care providers, many of whom are also parents. We all want the best and healthiest environment for our children. Vaccines continue to be an important and healthy choice.

Kristen Feemster, M.D., MPH, MSHP, is a pediatric infectious diseases physician and Director of Research for the Vaccine Education Center at the Children’s Hospital of Philadelphia (CHOP). Trained at Yale and Columbia Universities, she’s also an advisory board member for Parents with Kids of Infectious Diseases (PKIDS) and serves on the Advisory Commission for the National Vaccine Injury Compensation Program. Find out more at


Vaccine Resources

It can be challenging to find comprehensive, reliable information about vaccines. Here are some resources we share with families: