Shortage of vaccines stirs concern for children

(CNN) -- A limited supply of tetanus and several other vaccines in the United States is stirring concern that more children could begin contracting otherwise preventable diseases.

In addition to the tetanus vaccine, the shortages are affecting vaccines for diphtheria and pertussis -- also known as whooping cough -- along with the new pneumococcal vaccine that helps protect children against meningitis, pneumonia and some other diseases, health officials said.

In some pediatricians' offices, parents expecting to get scheduled shots for their children are being told to come back later. But if parents don't bring them back, officials said they fear more children will start coming down with the diseases.

It's unclear exactly how many children haven't been receiving the vaccines because of the shortages, which officials have attributed to fewer companies making the vaccines and some recent manufacturing problems.

U.S. Sen. Jack Reed, D-Rhode Island, said the nation's immunization program for children has been a victim of its own success.

"We tend to take it for granted," Reed said Tuesday. "We haven't invested some money at the federal level, or most particularly, the state level, to have the infrastructure to deliver these vaccines."

The senator, who has asked the General Accounting Office to look into the problem, said he wants the federal government and states to pay more attention to the problem.

"We have to strengthen the system because immunization is the best weapon we have against disease," he said, "and it's been remarkably successful, and we have to reinforce the success with real resources."

Dr. Ed Thompson, Mississippi's chief health officer, noted that while the United States isn't seeing outbreaks of vaccine-preventable diseases yet, they could happen.

"We don't see children die of diphtheria and pertussis anymore," Thompson said, "but we could begin seeing that again if we don't heed the early warning signs of something being badly wrong with our public immunization system and our private immunization system."

He urged parents to make sure children get their shots.

"Be tenacious, be stubborn, make sure you know whether your child is due for any immunization or not," he said. "If your child is, seek out those immunizations."

-- CNN Medical Correspondent Elizabeth Cohen contributed to this report.