Diving after a Corona Infection
technical Science 20.05.2020Preface
While in some countries the Covid-19 pandemic has only recently start to spread and making its victims, there are also countries that believ that they have passed the top of the crisis and take the first steps to easy the lock down measures back to normal life.
What does that mean for the healthy sport diver and special what does that mean for the sport diver who has been infected by the Sars-Covid-19 virus. Different hyperbaric medical societies and diving federations have issued advices and statements about diving after a Corona infection. At the end of the text we will provide some links to these different statements.
There are similarities among those advices and of course also differences. The Corona virus is a new virus and a lot about its behavior is yet unknown. In the beginning it was called ‘just a normal common cold virus’ but that proved to be wrong. Although most infected people have just minor symptoms, it is now known that it also can cause serious medical problems, sometimes with a fatal effect. It can also cause longer lasting symptoms. Long after the primary infection has gone.
That means that the advices give, can only be an advice for this moment. Research, experience, discoveries and more understanding in the nearby future may change the advice.
When your national diving federation issues their own statement, we advise you to follow those regulations. This also is the case when the government of your country give other regulations.
Highlights previous CMAS statements
- All recreational diving and all national and international sport activities and competitions are postponed until further notice
- All non-essential medical examinations for divers to gain a fit-to-dive assessment are postponed. Diving federations requiring a diving medical examination should consider providing interim guidance e.g. by prolonging the validity of the current medical certificate.
These measures are all subject to revision in accordance with the epidemiological situation in each country.
Diving after infection
Normally sport divers, after a viral infection, resume their activity without further investigation. They consider themselves fit to dive. In the case of a Corona infection, for the time being, you have to consider yourself not naturally fit to dive. Consider the next advices
- When you have had a proven Covid-19 infection but with no symptoms at all, you have to wait at least for one month before going to dive again.
- Divers with a Covid-19 infection with symptoms, have to wait three months before resuming their diving activities.
- Divers infected by Covid-19 who have had serious symptoms and who have been hospitalized (with or without ventilation) should at least wait for a period of three to six months without any complaints. After that period, they had to be examined by a physician familiar with diving medicine.
What about divers that have not been tested?
Divers who have never had symptoms and have not been tested (who either have not been infected or have had the infection completely asymptomatic) may not have developed immunity against the disease (currently, serological tests are not widely available and do not confirm with 100% certainty a sufficient level of immunity). Therefore, they may still be infected by other divers and would need to observe a waiting period after the release of the confinement period. The duration of this waiting period may be variable depending on the local situation (type of diving, location and local organisation).
Specific remarks
Lung
Risk for pulmonary overpressure syndrome (lung barotrauma)
A person who has had COVID-19 infection with severe pulmonary symptoms may suffer from prolonged or even permanent pulmonary damage, even if the lung function seems to have returned to (near) normal. This damage may give a higher risk for lung barotrauma, even after dives without a rapid or uncontrolled ascent. Therefore, it is recommended that a diver who has been hospitalised with or because of pulmonary symptoms in relation to COVID-19, should, after the (at least) three-month waiting period (as indicated above), undergo complete pulmonary function testing as well as a high-resolution CT scanning of the lungs. Pulmonary function testing should include FVC, FEV1, PEF25-50-75, RV and FEV1/FVC), and the CT scan should show a return to normal, before resuming diving. It is important that these tests should be interpreted and validated by a medical officer with specific knowledge of diving medicine. If major pulmonary symptoms have been present, even if not requiring hospitalisation, pulmonary damage may have occurred and a pulmonary function testing and CT-scan are useful tests. (SBMHS quote)
Heart
Risk for cardiac events: in the context of general illness and severe pulmonary infection, a COVID-19 cardiomyopathy may not a prominent symptom and may even go unnoticed during the acute phase of the disease. This however may be the cause of heart muscle damage and subsequent scarring. Cardiomyopathy or cardiac scar tissue may be an important factor in the occurrence of sudden cardiac failure and sudden death during diving immersion. Therefore, it is recommended that a diver who has been hospitalised with or because of cardiac or pulmonary symptoms in relation to COVID-19, should, after the three-month waiting period (as indicated above), undergo cardiac evaluation with echocardiography and exercise test (exercise electrocardiography) to ascertain normal cardiac function. If major pulmonary symptoms or extreme fatigue/exhaustion have been present, even if not requiring hospitalisation, this may indicate a possible cardiomyopathy and cardiac testing is useful. (SBMHS quote)
Links
EUBS & ECHM statement - European Underwater and Biomedical Society and European Committee for Hyperbaric Medicine
Tauchen nach COVID19-Erkrankung - DLRG Deutschen Lebens-Rettungs-Gesellschaft
UHMS statement - Undersea & Hyperbaric Medical Society
SMMHS-BVOOG statement (E) - Belgian Society for Diving and Hyperbaric Medicine
SMMHC-BVOOG position (F) – Société Belge de Médicine Hyperbare et Subaquatique