Drowning is a major concern with kids at the pool or beach, but the threat isn't necessarily over when you're headed home. Breathing in just a small amount of water can cause life-threatening issues several hours after the fact.

An episode known as delayed drowning is something parents should be on the lookout for, according to experts. The secondary threat isn't very common, but it is deadly if symptoms aren't spotted in time.

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According to Dr. Sanjay Mehta, division chief of the Pediatric Emergency Department at CentraState Medical Center in Freehold, the initial drowning scare, even if it only involves a brief episode of coughing, can cause a cascade of health-related events over the next 24 hours.

"The body has a systemic reaction," Mehta said. "The blood vessels that supply the lungs essentially become leaky, and water that's supposed to be in the blood vessels ends up becoming engorged in the lungs."

Symptoms, which may take hours to present themselves, include persistent coughing or wheezing, extreme fatigue, a sore throat and change in the color of the face. Most of the symptoms point to a lack of oxygen, according to Mehta.

Delayed drowning goes beyond the summer months. Even a routine bath can result in extended submersion and fluid inhalation, especially if parents fail to keep a close eye on their children.

CentraState has not dealt with any of these cases yet this summer, according to Mehta, but several near-drowning victims have been admitted for observation to make sure no secondary symptoms arise.