French drugmaker Sanofi said Monday the Food and Drug Administration approved a new version of its flu vaccine Fluzone that is designed to prevent four types of the virus.

Sanofi said Fluzone Quadrivalent is designed to protect against two types of influenza A and two types of influenza B. Fluzone is the only flu shot recommended in the U.S. for infants and very young children, and Fluzone Quadrivalent is approved for children as young as six months. Sanofi also makes Fluzone HD, a high-dose vaccine intended for people over 65, whose immune systems tend not to respond as strongly.

Seasonal flu vaccines typically protect against only three strains of the flu.

The new vaccine will be available for the current flu season, Sanofi said. Flu season runs from October to May and usually peaks in late January and early February.

The U.S. Centers for Disease Control and Prevention recommends that everyone six months and older get a seasonal flu shot every year unless they have severe allergic reactions to past flu shots or to eggs, which are used in growing the vaccine, or Guillain-Barre Syndrome, a rare condition that is sometimes linked to vaccines.

Sanofi shares fell 9 cents to $53.28 in afternoon trading.