A vaccine that has dramatically curbed pneumonia and other serious illnesses in children is also having an unfortunate effect: promoting new superbugs that cause ear infections
On Monday, doctors reported discovering the first such germ that is resistant to all drugs approved to treat childhood ear infections. Nine toddlers in Rochester, N.Y., have had the bug and researchers say it may be turning up elsewhere, too.
Wyeth anticipated this and is testing a second-generation vaccine. But it is at least two years from reaching the market, and the new strains could become a public health problem in the meantime if they spread hard-to-treat infections through day care centers and schools.
It is a strain of strep bacteria not included in the pneumococcal vaccine, Wyeth’s Prevnar, which came on the market in 2000. It is recommended for children under age 2.
Prevnar, however, is losing its punch because strains not covered by the vaccine are filling the biological niche that the vaccine strains used to occupy, and they are causing disease.
One strain in particular, called 19A, is big trouble. A new subtype of it caused ear infections in the nine Rochester children, ages 6 months to 18 months, that were resistant to all pediatric medications, said Dr. Michael Pichichero, a microbiologist at the University of Rochester Medical Center.
The children had been unsuccessfully treated with two or more antibiotics, including high-dose amoxicillin and multiple shots of another drug. Many needed surgery to place ear tubes to drain the infection, and some recovered only after treatment with a newer, powerful antibiotic whose safety in children has not been established.
–Scientists from a drug company and two labs analyzed more than 21,000 bacterial samples from around the nation and found 19A increasing. Among children 2 and under, the portion of samples that were this strain rose to 15 percent in 2005-2006, from 4 percent in the previous three years.
–A British lab tracking respiratory infections in U.S. kids found that the 19A strain accounted for 40 percent of drug-resistant cases.
–University of Iowa researchers found 19A accounted for 35 percent of penicillin-resistant infections in 2004-05, compared with less than 2 percent the year before the new vaccine came out.
Categories: . Vaccine-induced pathogen strain replacement