COVID-19 and Diving: March 2021 Update

For more than a year, the entire world, including the medical community, has been focused on the COVID-19 pandemic. Significant advancements, including effective vaccines, have been made in prevention and treatment. In addition, an ever-growing body of sound scientific information has been discovered — at great human cost — since the pandemic began.

Alarming speculation has given way to compelling scientific studies. Well-conducted studies unfortunately take time to conduct. Disseminating the data can be even harder, especially if the results do not proclaim sensational doom. For instance, initially there were calls to permanently disqualify anyone who had COVID-19 from diving and even military service. Fortunately, good science intervened, and these recommendations were discounted and removed.

There is still much more to be learned, especially about the effects of the disease post-infection. The receptor sites necessary for the virus to enter the cells are found in a variety of different locations throughout the body, and therefore effects have been reported in most organ systems with a variety of findings related to that organ system. In addition to the results of this direct cellular infection, many early reports included complications not directly related to the infection but secondary problems that complicate severe illness. Prolonged hospital stays, underlying medical conditions, mechanical ventilation, secondary bacterial infections, and others each have their own problems and their own negative impacts on recovery. With regard to diving, we are particularly concerned about the pulmonary and cardiovascular aspects. There are also concerning neuro-psychological problems that will need to be studied further to determine the cause and the implications for full recovery.

Consequently, there is no one-size-fits-all approach for a medical assessment of dive fitness after COVID-19; each case must be addressed individually by the patient and the physician team. Formal networks of medical care are doing an amazing job of identifying and treating patients at home and hospitalising only those who are quite ill. Successful care has evolved as caregivers have gained experience. It is tailored to the patient’s actual needs rather than a simple one-size-fits-all protocol. Most patients have remained with their primary care team through recovery and return to work and exercise with amazing success. The patient’s condition should be dynamically monitored by the physician team, as there are real concerns with recovery involving the heart, lungs and vascular system. As with recovery from any serious condition, a doctor should be consulted before returning to diving; do not assume a recovered patient is medically fit to dive without evaluation by a physician.

DAN recommends the following:

1. If you suspect or know you are infected with COVID-19, immediately establish contact with your primary care physician (PCP); knowledge of diving medicine is not crucial at this point. The critical phases are diagnosis, quarantine, treatment, recovery, and return to full exercise capacity. Return to full exercise capacity means being free of all complications, including chest pain, fatigue, and shortness of breath.
2. The severity of the infection can range from asymptomatic to ICU admission with mechanical ventilation. Various specialist may be involved in various stages of your care. This may include additional evaluation and testing even after the acute illness should you continue to have complaints after your recovery.
3. Upon full recovery without any complaints, a return to your baseline exercise capacity, discontinuation of further follow-up care by your physician team, and freedom from restrictions on prolonged strenuous exercise, a return to diving evaluation can be considered.
4. It is recommended that you see a physician trained in dive medicine to confirm your safe return to diving. However, that determination can be obtained from your physician team for those divers described in #3 (i.e., fully recovered, asymptomatic, at full exercise capability and without abnormalities). A discussion with a dive medicine physician or a call to DAN would be advised in the event of any persistent complaints or abnormalities.
5. It is important to understand that various diving organisations will have their own requirements for the return to diving after COVID-19 infection, and these must be followed if you wish to be part of that organisation’s diving operations. You must contact that organisation for its specific guidance.
6. There are several algorithms, including one specific to divers by Sadler et al., that have been developed to help your physician team make a sound evaluation. As more is known, these recommendations may require modification.
7. It has probably been some time since you have been diving. Thus, it is highly recommended that once cleared to do so you check your gear and perform shallow dives in confined water to review skills and ensure you have no problems. Remember not to let a long delay steal your successful return to diving. Remember the mnemonic THEFT:

• Training
• Health
• Equipment
• Fitness
• Travel

The diving environment is unique, and problems that occur at depth have more severe consequence than problems on the surface. Returning to diving prior to a complete recovery may cause injury or psychological trauma. DAN continues to evaluate the current recommendations for the best information. We are always updating the DAN website with new information about how COVID-19 impacts diving and advising divers about how to mitigate the risks associated with this pandemic. Be sure to check back often at DAN.org/COVID-19, and please share these resources with your doctor. DAN’s most recent webinar about COVID-19 and diving can be seen here.

If your physician is unfamiliar with diving medicine, these resources can offer guidance about how certain conditions that may not be concerning for the general population might be worth special consideration in divers.

Here are some additional resources to explore:

• Guidelines for Lifelong Medical Fitness to Dive
• Undersea & Hyperbaric Medical Society (UHMS) Recreational Diver Medical Screening System
• UHMS Diving Medical Guidance for the Physician
• UC San Diego Guidelines for Evaluation of Divers During the COVID-19 Pandemic
• Diving after SARS-CoV-2 (COVID-19) infection: Fitness to dive assessment and medical guidance. Diving and Hyperbaric Medicine Journal, Volume 50 No. 3 September 2020 (Sadler et al.)

DAN is conducting a large study to investigate diving after COVID-19, and we are currently seeking divers who have had COVID-19 and wish to share their experience. Learn more here.

Please do not hesitate to contact us if you or your doctor have any additional questions or concerns. The DAN Medical Information Line at +27 82 810 6010 or via email at danmedic@dansa.org.