San Diego County health officials say a recent outbreak of chickenpox at a Carlsbad elementary school provides a good lesson. Four kids and one adult who became sick were not immunized.
Chickenpox is a highly contagious disease that causes an itchy rash and a fever. It's also preventable through two doses of the chickenpox vaccine.
Prior to the introduction of the vaccine, the disease would sicken about four million Americans each year.
Dr. Eric McDonald, San Diego County's deputy public health officer, said chickenpox is especially dangerous for adults.
"If you've ever taken care of somebody who is very ill from chicken pox, which I have, then you have respect for the illness, and realize that it makes sense that the entire population be immunized," Dr. McDonald said.
One of the school children who got sick in the recent outbreak had been immunized. The chickenpox vaccine is said to 98 percent effective.