If you’ve been watching Fox News and the Casey Anthony trial as many people have, you know that the defense has put forth the theory of accidental drowning to cover poor Caylee’s untimely demise two months before her third birthday.

You’ve seen world class forensics expert, Dr. Michael Baden, talk about the “diatom test for drowning,” where a substance in a victim’s bone marrow can be tested and compared to the same substance in the water at the time of death.

Most media observers of the Anthony trial, and the numbers are surely now in the hundreds of millions, do not find the accidental drowning defense particularly credible, even after they see photos of the poor child ascending the ladder to the pool. But curiously, there is a new study just published in the reputable journal Pediatrics, that reveals that accidental drownings of infants are much more common than most people thought. The prevalence of this kind of accident isn’t evidence in itself, but it is certainly curious.

The study, published in the July edition of Pediatrics, looks at injury and fatality data complied by the U.S. Consumer Product Safety Commission from 2001 to 2009 regarding drownings and near drownings in above ground portable pools. The results are shocking. 209 deaths and 35 near deaths were reported, and 94 percent involved children younger than 5 years. The study concludes that “the use of portable pools in residential settings poses a significant risk of submersion-related mortality to children, especially in the < 5-year-old age group.”

Clearly, the study concludes, protective devices including fencing, pool alarms, safety covers and consumer education are necessary. It's obvious that the problem is much greater than the study reports, and parents are not paying enough attention, falling asleep and leaving kids unobserved. Accidents involving portable pools kill a child once every five days in the summer.

It takes very little water or immersion for a child to drown. Most drowning victims have so-called “wet drowning” meaning their larynxes (voice boxes) relax allowing water to enter the lungs. But very little water is needed to cause drowning. For an infant under 50 pounds, less than 3 ounces of water is generally found on autopsy. Babies panic in the water, suck in water, and drown quickly and silently. Drowning can occur in mere seconds.

Watching the over-hyped Casey Anthony case with all its media fascination, I’ve been looking for a medical moral. Something I can use to warn my patients. A take-home message that we can all learn from. Now I’ve found one -- watch your infants very closely at all times and institute the greatest caution and precaution around your swimming pools. This is not the likeliest end for poor Caylee Anthony's life, but it could be for your child -- or mine.

Marc Siegel MD is a professor of medicine and Medical Director of Doctor Radio at NYU Langone Medical Center. He is a Fox News Medical Contributor and the author of "The Inner Pulse: Unlocking the Secret Code of Sickness and Health."