(AP) -- Pfizer says the Food and Drug Administration has approved an updated version of its best-selling infection vaccine for children.

Prevnar 13 is intended to reduce the risk of infection by 13 varieties of pneumococcal disease, which causes ear infections, meningitis and . The new vaccine adds protection against six additional varieties of bacterial infection compared with the current vaccine.

The vaccine, developed by Wyeth, is the first product to win FDA approval since Pfizer acquired Wyeth last year.

With sales of $2.7 billion in 2008, Prevnar was considered a key product in Pfizer's decision to purchase Wyeth for $68 billion.