Anthony S. Fauci, M.D., Director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health in Bethesda, Maryland, issued a notice Monday urging parents to get their children vaccinated. His note follows.

Vaccines are essential for protecting children against infectious diseases such as measles, mumps, rubella and whooping cough. Many of these diseases are largely forgotten in our country.

Before vaccines became available, however, these diseases exacted a huge toll.

For example, before the measles vaccine was licensed in 1963, the virus infected at least 2 million Americans a year, causing 500 deaths and 48,000 hospitalizations.

It may be upsetting for parents to see their babies or young children receive several vaccinations during a medical visit. However, these shots are necessary for protection from multiple dangerous — and sometimes deadly — diseases.

Vaccinations typically cause only mild side effects, such as redness or swelling at the injection site; serious side effects are very rare. The public health benefits of vaccination far outweigh the possible side effects.

When children are vaccinated, their immune systems develop infection-fighting antibodies to protect them from contracting the targeted disease if they are exposed to it later in life.

The full course of recommended childhood vaccinations, largely completed for most children by age 6, not only protects the vaccinated child but also contributes to a larger umbrella of protection known as “herd immunity.”

By doing so, it helps prevent the spread of disease to those who cannot be vaccinated, including newborns who are too young to be vaccinated, and people with compromised immune systems, who cannot effectively develop antibodies to fend off disease.

Many diseases against which children in the United States are immunized are rare in this country because of mass vaccination programs. However, these diseases are still found in other parts of the world and can be reintroduced into the United States by travelers, and then spread within our communities among people who have not been vaccinated.

The current resurgence of measles, a highly contagious and potentially deadly disease that was declared eliminated in the United States in 2000, is a painful reminder of the need for vaccination.

Parents and caregivers, please vaccinate your children to protect them, as well as friends, family, and community members who cannot be vaccinated.