Pediatric immunization also offers benefits for adults

The immunization of children helps reduce the spread of infectious diseases by breaking the chain of transmission.

Issue: August 2008

The immunization of children can have significant and wide-ranging public health benefits. These benefits often extend beyond the health of pediatric patients and are conferred to people of all ages, according to Ron Dagan, MD, professor in the department of pediatric infectious diseases at the Soroka University Medical Center of Ben-Gurion University in Beer-Sheva, Israel.

“Pediatric immunization benefits public health in several ways,” Dagan said in an interview with Infectious Disease News. “First, many vaccinations lead to lifelong benefits. For many vaccines, once a child is immunized, he or she will grow up to be an adult who carries the benefits of this vaccination through life, maintaining immunity toward that disease. Second, herd immunity plays an important role. Most vaccines we give fight against infectious diseases that are often transmitted by children. If children are immunized, this helps to reduce the spread of infections to people of all ages, even if others have not received the vaccination. By vaccinating children, we break the chain of transmission.”

Dagan said the clearest example to demonstrate the benefits of herd immunity can be seen in schoolchildren. “If we talk, for example, about influenza, the main transmitters are often young children,” Dagan said. “These children are often in close contact with one another in crowded classrooms or day care centers. If one child gets sick, many more also are likely to get sick if none of them have been vaccinated. If all children are unvaccinated, one child can infect the group. But if 95% of the children are vaccinated, the other 5% are protected because they are in an environment where the virus is not spreading.

But the benefits of herd immunity often extend to the general population and are not limited to only patients of a similar age range. “Children often go home from school and pass the disease on to other family members, including parents, grandparents and older or younger siblings,” Dagan said. “With increased pediatric immunization, even family members who have not been vaccinated will be at a lower risk for disease transmission because the chain of transmission is broken. These family members will, in turn, be less likely to pass on the disease to coworkers and friends. So if more children are vaccinated, an outbreak among children is unlikely, which protects hundreds of households.”

Dagan cited Israeli public health officials’ work in reducing the spread of hepatitis A as an example of the benefits of pediatric immunization. “Israel was the first country to introduce the hepatitis A vaccine for children; it is now given to all Israeli children aged younger than 2,” Dagan said. “Israel now has fewer than 200 cases of hepatitis A. There has been a 95% reduction of hepatitis A in all age groups since this program began.”

Dagan said this program was successful because of its focus on immunizing children. “If we target the vaccine to those who are the most likely transmitters, there will be a stronger effect across all age groups,” he said.

Antibiotic resistance

Pediatric immunization also may have a beneficial effect on reducing antibiotic resistance. When more antibiotics are provided to children, there is a greater risk for the spread of antibiotic resistant germs.

“Pediatric immunization is another way to fight antibiotic resistance because any action that will reduce diseases in children will reduce the incentive to give antibiotics,” Dagan said. “If we were able to vaccinate the entire population of children, significantly fewer would get sick and fewer would have to take antibiotics. This would help to maintain the strength of antibiotics against resistant bacteria.”

Dagan added that some vaccines may be beneficial in fighting specific serotypes of organisms that are antibiotic resistant. “More specifically, vaccines like the pneumococcal conjugate vaccines may reduce specific serotypes that are antibiotic resistant, leading not only to reduced antibiotic use but also to increased susceptibility of pneumococci to the existing antibiotics,” he said. – by Jay Lewis

For more information:

Dagan R. Why should adults care about pediatric vaccination?: The role of pneumococcal conjugate vaccine in protecting adults from disease and antibiotic resistance. Presented at: The 18th European Congress of Clinical Microbiology and Infectious Diseases; April 19-22, 2008; Barcelona, Spain.