Scuba Diving Can Be Hazardous to Your Health

Competitive free diver Julia Wheeler, 31 was recently training off the coast of Bali when fellow diver, Trista Fontana, spotted tons of plastic garbage drifting toward them. When the video got posted on the internet, social media went wild. And so it should.

Besides the hazard to marine animals that mistake discarded plastic items for food, much of the plastic will contain the dregs of previous contents: not just human food, but even blood, urine, and chemical contaminants.

People have been discarding their unwanted garbage in the sea for centuries. If you were to dive among the antiquities being discovered in Alexandria harbor by Frank Goddio, you'd be well advised to wear a drysuit and a full-face scuba mask, such is the level of pollution.

The same can be said of much of the ocean, thanks to the growing world population. Last month, Undercurrent noted the risk of infection while diving Indonesia's Lembeh Strait, but this is not a problem unique to Lembeh, and in many tropical areas, the various pathogens encountered can be more virulent.

In 2015, one of Undercurrent's travel writers wrote of a trip in the Philippines, "Not everything goes well for everyone on a dive trip, unfortunately. A serious and skilled photographer in my group lost several diving days when his wife inadvertently poked him in his (one good) eye. It became infected, and after seeing a local doctor, he stayed in his darkened cottage for the next three days."

Paul Duxfield (Yorkshire, UK), a one-time dive guide and now teaching underwater photography, was less lucky. He cut his finger trying to break a stray thread from the stitching on his wetsuit. It became infected, and eventually, he had it amputated.

Way back in 2009, Ernest Campbell, MD, writing as "Scubadoc" (www.scuba-doc.com), raised awareness of the variety of bacterial hazards we divers should be aware of: enterobacteria, dysentery inducing shigella, salmonella, klebsiella responsible for rhinitis and respiratory infections and actinomycetes (leading to sepsis and liver damage). The list goes on and includes viruses, parasites and noxious chemicals from the thousands of spills each year.

The opportunity for infection can be insidious. In September 2008, Undercurrent published an article regarding pathogens in freshwater rinse tanks. When 13 people suffered conjunctivitis the same week in Fiji, the cause was tracked down to one infected local individual who had rinsed his mask in the rinse tanks of both the boats they were using. As for staying clear of the likes of conjunctivitis, the best thing to do is to rinse your mask separately and avoid communal buckets.

This March, GMA News reported that the Philippines Department of the Environment and Natural Resources had found that Coron Bay, a major tourist attraction in Palawan, was "swarming with a high amount of bacteria found in human feces and other forms of coliform due to wastewater being discharged directly from hotels and restaurants."

In April, President Duterte of the Philippines closed the island of Boracay to tourism completely for six months, saying it was turning into a cesspool. The island is home to 500 tourism-related businesses, but the shut-down follows growing concern over the island's environmental health. Duterte accused hotels and restaurants of dumping sewage directly into the surrounding waters.

In a comprehensive paper1, James H. Diaz, MD, states, "Many species of bacteria, especially Staphylococcus aureus and Streptococcus species, have been isolated from marine wounds and commonly cause impetigo, pyodermas, and erysipelas.

"Travelers with well-known risk factors for the increasing severity of marine infections, including those with open wounds, suppressed immune systems, liver disease, alcoholism, hemochromatosis, hematological disease, diabetes, chronic renal disease, acquired immunodeficiency syndrome, and cancer, should be cautioned about the risks of marine infections through exposures to marine animals, seawater, -- and the accidental ingestion of seawater."

Traveling with a single broad-spectrum antibiotic may not be sufficient, and one may need a specific antibiotic to treat a specific infection. So, should you develop an infection, seek out a skilled medical practitioner. Meanwhile, keep your regulator in your mouth, your mask on your face and treat any skin abrasions with antiseptic.

So, if you're diving in tropical water, what should you do?

Peter J. Denoble, Vice President Mission, DAN, offered the following advice: "External ear infections are a hazard in warm tropical waters worldwide, infection of cuts and scrapes, or eye-pokes are also widespread. Walking on the beach and wading the shallow waters carries risk of infection, not only abroad, but also on USA mainland beaches. The hazard of infections increases with the denser population as well as with a lack of sanitation. The main message should be that protection from cuts and scrapes, as well as protection of eyes and all mucosa, ingestion or inhalation of water, should be a second nature of divers (and swimmers)."

Also keep up to date on vaccinations: Hepatitis A and B, cholera, polio, typhoid, smallpox Diphtheria, and Tetanus. If the water looks polluted or full of trash, avoid entering. Avoid taking out your regulator or removing your mask until you can rinse them -- and yourself -- in clean, fresh water. The same goes for all your life-support gear. If you get ill, the symptoms can take time to appear; be sure the medics understand that you may have been submerged in polluted water.

(1 Diaz, J. H. (2014), Skin and Soft Tissue Infections Following Marine Injuries and Exposures in Travelers. J Travel Med, 21: 207-213. doi:10.1111/jtm.12115)