It’s every parent’s worst nightmare. It only takes seconds for a child to drown, often so silently no one notices before it’s too late. Drowning is one of the leading causes of death in children, leading to nearly 1,000 deaths in the U.S. each year.

That’s why the American Academy of Pediatrics is putting the spotlight on prevention with some updated advice for parents.

“When a child is in and around water, we need constant attentive supervision, touch supervision, which means they are within an arm’s length of that child when they are in the water,” Dr. Sarah Denny, an emergency physician at Nationwide Children’s Hospital in Columbus, Ohio and an author of the AAP report, told CBS News.

Kids ages 1 to 4 are at the highest risk for drowning and many deaths happen when children have unexpected access to water.

“When kids are not expected to be in the water that’s when we need those barriers. That’s the four-sided isolation fencing that separates the pool from the rest of the house and the yard,” Denny said.

The AAP stresses all children should learn to swim and children and teens should wear life jackets when near bodies of water. Studies show that swim lessons starting around age 1 can reduce a child’s risk of drowning. Experts say the lessons need to teach children basic water skills, as well as water safety.

“Floating, grasping the wall, climbing in and out of the water turning back to the wall, a lot of times children end up falling into the water and they look to the furthest point and if they just turned around they would be better off,” said Katie Lee of the Goldfish Swim School in Long Island, New York.

See CBS News