The strong bump in traffic that drugstores received from a sprint-start to the flu season late last year appears to waning.

Walgreen Co. and Rite Aid Corp., two of the nation's three largest drugstore chains, both said this week that business from the flu slowed noticeably last month.

The Centers for Disease Control and Prevention had said in late January that flu cases appeared to be leveling off nationwide and declining everywhere except for the West. That appeared to play out last month with drug store sales.

Rite Aid, based in Camp Hill, Pa., said that its established stores saw a slight decrease in flu shots and flu-related prescriptions compared to February 2012. Sales of over-the-counter flu treatments were flat. Overall, the chain's revenue from stores open at least a year fell 3.6 percent last month.

The flu had a neutral impact on Rite Aid's February results after pulling strong traffic into its stores the previous month, according to Credit Suisse analyst Edward Kelly.

Walgreen, the nation's largest drugstore chain, the flu had a minor impact on prescriptions filled at stores open at least a year, compared with January. Flu shots, meanwhile, had no impact on sales from established stores. Walgreen, based in Deerfield, Ill., said this week that revenue from stores open at least a year fell 0.6 percent last month.

The country appeared to be headed for a doozy of a season early and the federal government took extraordinary steps to makes sure more flu medicines were accessible to those in need.

The season began earlier and the flu that struck was one that could make people sicker.

By mid-January, at least 29 children or teens had died from the flu-related causes, nearing the 34 pediatric deaths for all of the previous year's flu season.