This is one of the most critical issues facing parents: Are shots a personal choice or a civic duty?

As a pediatrician, I recommend all vaccines, but I admit that the shot schedule is constantly evolving. Doctors have repeatedly tweaked this schedule to make it safer and more effective (for example, over the past 30 years, the measles vaccine was pushed from 9 months to 12 months…and now is recommended to be given as late as 15 months of age).

I think of shots as falling into 2 different groups: 1) those given primarily to protect your child, 2) those protecting your child and your neighbors’ children.

The first group of shots stops infections like, rotavirus, hepatitis A, chicken pox and hepatitis B. They help your child but don’t give great protection to the community. That is either because the illnesses are very common (spread quickly through your neighborhood even if your child gets the shot) or hard to spread (difficult for your child to give it to others). (Note: Older kids, teens and adults are at risk for hepatitis B. It has caused thousands of cases of liver failure and cancer and so all citizens should eventually get this vaccine.)

The second group of shots stops infections that threaten your child and your community (your neighbor’s baby, the elderly, chronic disease sufferers, etc.). These shots include, whooping cough, influenza (flu), meningitis (Hib), pneumococcus (Prevnar) and measles. They miraculously halt diseases that are so contagious just one cough, one airplane flight or one germy doorknob can spread them like wildfire through your town.

I believe giving the first group of shots is a parent’s personal choice because the suffering you risk is mostly limited to your child and family.

However, giving the second group of shots is an important civic responsibility because delaying them creates a serious public health risk. By immunizing at least 95% of children with these shots we create “herd immunity” that can totally halt the spread of deadly epidemics in our communities. Herd immunity stymies the spread of disease the way that frequent rain keeps lightening strikes from starting raging forest fires.

Some doctors may fairly argue which vaccines should go into which groups. Some might say that the flu shot should be a personal choice. Skipping the flu shot, for example, may cause your child to be one of the 36,000 Americans who die from influenza this year, but it probably won’t stop a flu outbreak. While other’s would argue that the more kids vaccinated the less likely an epidemic can spread…and it would also help protect your vulnerable neighbors (those with cancer, on cortisone for asthma or arthritis or the very young or over 60-group). But, the important point is that the second group of vaccines is crucial if we are to protect children in our communities who are too young to get their own shots. Parents who skip these shots may not mean to harm others, but their action significantly increases the risk of avoidable suffering and death to innocent children.