Vaccines may open the door to other strains of illness
Wednesday, February 24, 2010
Since the pneumococcal vaccine was introduced in 2000, the incidents of pneumonia, bacterial meningitis and blood infections in children has been reduced by half.
The bad news? Other strains not covered by the vaccine are now taking center stage.
Specifically, there's been a 70 percent increase in the rate of children with empyema, according to a study in the journal Pediatrics. Empyema is a complication of pneumonia that makes breathing painful and often requires hospitalization and the use of a chest tube to treat.
Dr. Tina Tan, a physician at Children's Memorial Hospital's Division of Infectious Diseases, says she is treating empyema "all the time." Typically, she says, the children have already been diagnosed with pneumonia, but aren't improving.
"They have high fever, trouble breathing, they're vomiting, listless," she says.
There are more than 90 strains of pneumococci. Prevnar, the current vaccine, focuses on the seven strains that cause a majority of pneumonia cases in children under 5.
"But now," she says, "the other organisms that were around and had just been overshadowed before, now you're really seeing those organisms."
Soon, the Food and Drug Administration likely will approve a new vaccine that covers 13 strains of pneumococcus, including the strain most likely to cause empyema.
Specific recommendations, such as whether children who have already had Prevnar need this new vaccine as well, have not been provided yet, Tan says.