Better Health: Smart Health Commentary Better Health (TM): smart health commentary

Article Comments

How To Reduce Your Risk Of A Shark Attack

First, about sharks and shark attacks:

Sharks are found in oceans, tropical rivers and lakes. They range in size from 10 centimeters to over 15 meters (whale sharks). Approximately 30 out of 350 species have been implicated in human attacks. On average, there are fewer than 100 attacks reported each year worldwide, and less than 10% of these attacks are fatal. Sharks are superbly equipped predators, and can detect motion, chemicals, electrical signals, and vibration in the water, with a sensitivity that enables them to easily hone in on prey. The most dangerous sharks from a frequency-of-attack perspective are the white (“great white”, “white pointer”), tiger, bull, blue, dusky, hammerhead, and grey reef sharks. However, it is important to note that any shark, including the seemingly docile nurse shark, will bite a human if sufficiently provoked.

Sharks appear to have two major feeding patterns – the solitary pattern, in which a single shark attacks, and the “frenzied” pattern, in which a school of sharks become stimulated and from that group emerges an attacker(s). Some sharks can swim at speeds of up to 40 miles per hour underwater in bursts of motion. More than 70% of human victims are bitten only once or twice. Aggression seems to often be directed at a wounded or splashing (on the surface) victim.

The clinical aspects of shark bites include massive tissue loss, bleeding up to and including shock, and subsequent infection. Bites to the limbs are most common. The propensity for infection is great because of contamination with seawater, sand, plant debris, shark teeth, and the bacteria that reside within the mouths of sharks.

The general first aid principles are the same as those for other forms of trauma. These are to control the airway, support breathing, maintain the circulation, clean-trim-rinse wounds, apply appropriate dressings to the wounds, and administer antibiotics when indicated. In the field, depending on the degree of bleeding and remoteness from advanced medical care, bleeding control takes priority. Because the marine environment hosts a number of bacteria and other microorganisms that are not commonly a problem on land. The most important of these, from a human health perspective, are Vibrio vulnificus and Aeromonas hydrophila. In situations where an aquatic-acquired wound is sufficiently severe (particularly in a person who suffers immunosuppression) to necessitate the administration of an antibiotic(s), this knowledge must be taken into consideration. Antibiotics that usually are effective against Vibrio and Aeromonas species include the fluoroquinolones (e.g., ciprofloxacin), tetracyclines (e.g., doxycycline), and trimethoprim-sulfamethoxazole.

The odds of shark attack along the North American coastline have been estimated to be 1 in 5-7 million. The danger appears to be greatest during summer months, in recreational areas, during late afternoon and evening, in murky and warm water, in deep water and drop-offs, and upon surface swimmers. All of these factors relate to the intersection of humans and sharks in the water and shark feeding and attack behavior.

Shark attack prevention is obviously quite important. Here are some important risk mitigation recommendations:

1. Avoid shark-infested water, particularly at dusk and at night.
2. Do not swim with domestic animals in shark waters.
3. Swim in groups; pay attention to your companions.
4. Avoid turbid water, drop-offs, deep channels, and sanitation waste outlets.
5. Do not bleed in the water.
6. Avoid wearing shiny metal adornments that might mimic fishing lures. (This is particularly important to avoid barracuda bites.)
7. Do not carry tethered (dead or injured) fish.
8. Be alert for sharks when other fish in the vicinity act erratically.
9. Do not tease or corner a shark. (This is important for any wild animal, and is particularly important to avoid moray eel bites.)
10. Do not panic or splash at the surface of the water.

This post, How To Reduce Your Risk Of A Shark Attack, was originally published on Healthine.com by Paul Auerbach, M.D..


You may also like these posts

Read comments »


Comments are closed.

Return to article »

Latest Interviews

IDEA Labs: Medical Students Take The Lead In Healthcare Innovation

It’s no secret that doctors are disappointed with the way that the U.S. healthcare system is evolving. Most feel helpless about improving their work conditions or solving technical problems in patient care. Fortunately one young medical student was undeterred by the mountain of disappointment carried by his senior clinician mentors…

Read more »

How To Be A Successful Patient: Young Doctors Offer Some Advice

I am proud to be a part of the American Resident Project an initiative that promotes the writing of medical students residents and new physicians as they explore ideas for transforming American health care delivery. I recently had the opportunity to interview three of the writing fellows about how to…

Read more »

See all interviews »

Latest Cartoon

See all cartoons »

Latest Book Reviews

Book Review: Is Empathy Learned By Faking It Till It’s Real?

I m often asked to do book reviews on my blog and I rarely agree to them. This is because it takes me a long time to read a book and then if I don t enjoy it I figure the author would rather me remain silent than publish my…

Read more »

The Spirit Of The Place: Samuel Shem’s New Book May Depress You

When I was in medical school I read Samuel Shem s House Of God as a right of passage. At the time I found it to be a cynical yet eerily accurate portrayal of the underbelly of academic medicine. I gained comfort from its gallows humor and it made me…

Read more »

Eat To Save Your Life: Another Half-True Diet Book

I am hesitant to review diet books because they are so often a tangled mess of fact and fiction. Teasing out their truth from falsehood is about as exhausting as delousing a long-haired elementary school student. However after being approached by the authors’ PR agency with the promise of a…

Read more »

See all book reviews »