Washington: A major US insurance company found itself on the defensive Monday after its sobering Super Bowl ad about children who die in preventable accidents triggered a social media backlash. Nationwide said it wanted to raise awareness about accidental childhood deaths, which experts say occur about once every hour in the United States.

"I couldn't grow up because I died from an accident," says a young boy in the ad, after regretting he will never be able to ride a bike, get married or travel the world. Haunting images follow -- of an overflowing bathtub, cleaning solvents under a kitchen sink, and a large flat-screen television set that fell onto the floor. "The number one cause of childhood death is preventable accidents," stated the 45-second ad that promoted the Twitter hashtag #makesafehappen.