New findings show that from 2003 to 2006, strep infections (group B streptococcus, GBS) increased among black newborns in the United States despite 2002 guidelines by the Centers for Disease Control and Prevention (CDC) to prevent them.

According to data from a surveillance system published in the CDC’s Morbidity and Morality Weekly Report, the rate of strep infection in the first week of life (early onset) for white infants remained at a little over one quarter of a case per 1,000 live births from 2003 to 2006. By contrast, the rate almost doubled in cases per 1,000 live births among black infants, climbing from 0.53 to 0.86 cases. The cause of the difference is uncertain, and the report emphasized that “continued monitoring is needed to follow trends (in this group) to determine whether additional interventions are warranted.”

The CDC has set new guidelines for pregnant women to get tested for strep infection before they go into labor, so they can start an antibiotic regimen if needed. Strep—which is passed from the mother to the baby during delivery—is the most common cause of blood infection and meningitis in newborns. It can also cause pneumonia. Between 10 and 20 percent of babies infected with strep die, and those who survive are at risk for permanent brain damage.