Medical Assessment for Fitness to Dive after Covid-19 Infection

To date over 21 million people in the UK have had proven Covid-19 infection. The true number is thought to be much higher due to a variety of reasons including testing not being easily available in the early months of the pandemic, those with no or minor symptoms not testing and those that did failing to report their positive result to the NHS.

This could mean that well over half of the UK population have so far been infected with Covid-19.

Significance of Covid-19 infection for divers

It is now well known that Covid-19 can seriously damage the lungs, heart, and other organs in the body. For those that survive Covid-19 (probably 98% of those infected) we do not know how many will have significant permanent damage and how many will only have temporary damage, but for an unknown length of time. The number of patients diagnosed with Long Covid is increasing. Even those with ‘mild’ symptoms have been identified as having lung damage on chest x-rays and CT scans.

Lung damage in divers is a significant risk factor for pulmonary barotrauma (causing e.g. a pneumothorax or CAGE) on ascent in the water. The lung damage may also increase the risk of developing a right-to-left shunt leading to decompression illness in a similar manner to those with a Patent Foramen Ovale (PFO.)

Heart damage, which may go unnoticed on dry land, may decrease exercise tolerance, increase the risk of developing cardiac arrhythmias and myocardial infarction underwater. It may also lead to a decompensation with exercise causing hypoxia. An inadequately functioning heart will increase the risk of Immersion Pulmonary Oedema, which is thought to be the largest cause of cardiac diving fatalities, even before the Covid pandemic.

Covid-19 infection is constantly changing. The early variants often led to severe symptoms and a relatively high fatality rate along with a significant risk of developing Long Covid. In the last 3-6 months the predominant variant has been Omicron, which whilst being highly contagious has a much lower risk of severe illness and causing lung / heart damage.

Research suggests that 40-80% of people who have not had any Covid-19 related symptoms may have actually had a mild form of the illness without realising it. Recently in the UK freely available lateral flow tests have identified many people with asymptomatic Covid-19 infection, especially with the omicron variant. Therefore, there is a case to argue that everyone should be considered to have had Covid-19 infection and should seek medical assessment for fitness to dive.

Reasons for needing a medical assessment

There is little regulation in recreational diving and often qualified divers are free to dive without any approval systems. However, there are several times when some form of medical assessment will be required:

1.       All training agencies, when commencing a course, insist on the student completing a medical health declaration form. If this form indicates that a medical assessment and a physician’s clearance to dive is required, then this must be obtained before any in water activity.

2.       Recreational dive providers may also require a health declaration to be completed and a medical certificate provided if indicated, for their clients.

3.       Travel & Diving insurance companies may require a medical certificate if the diver has, or had, any medical problems.

4.       Professional level divers e.g. instructors / divemasters on commercial recreational diving instruction courses in the UK must have an annual HSE diving medical assessment.

5.       Personal choice for the diver’s own wellbeing.

Health declaration forms

When learning to dive or taking diving courses the training agency usually requires a health declaration form to be completed. For commercially organised courses e.g. PADI, RAID, SSI, SDI the form used is the (World) Recreational Scuba Training Council (RSTC) medical declaration.

 Diver_Medical_Participant_Questionnaire_10346_EN_English_2022-02-01.pdf (uhms.org)

This form was updated in 2020 and the first question was about being diagnosed with Covid-19. A positive response then required a doctor’s sign off before any in water activity. Due to the standards of many training agencies this would then require an annual medical assessment, even if no damage from the Covid-19 infection had been identified. In January 2022 a revised form was issued which stated that after a satisfactory medical assessment following Covid-19 infection, then no further annual reviews would be required. Several weeks later in February 2022 a further updated form was published. This removed the reference to having had a Covid-19 infection and the only question that may apply is now “Symptoms affecting my lungs, breathing, heart and/or blood in the last 30 days that impair my physical or mental performance”. The implication being that 1 month after any Covid-19 infection the person will always be back to normal. This is contrary to experience to date!

Searching recreational diving websites reveals that all four of the RSTC medical declaration forms are currently being used, so divers may be required to complete any of these forms with or without reference to having had Covid-19. The prudent diver will need to clarify with their chosen dive provider before arriving for the diving session, or disappointment may result when diving is refused.

In the UK there are dive clubs e.g. BSAC, SSA that also provide recreational diving tuition. They use the UKDMC medical declaration form. Again, there is a specific question regarding having had Covid-19. If the answer is positive, then the diver must be assessed by a UKDMC medical referee to be approved to dive.

This medical certificate does have a facility to indicate that medical issues may be cleared for an extended period or even indefinitely without needing further annual approval by the medical referee. These extended certificates may not be recognised by other diving providers or may not comply with local laws where everyone is required to have an annual medical certificate.

Guidelines for the medical assessment of divers post Covid-19

 Significant online reports relating to this are available at:

1)      Dr Frank Hartig’s case series - https://www.wetnotes.eu/tauchen-nach-covid-19-erkrankung/

2)      Belgium Society of Diving’s guidance on assessing divers – 12^th April 2020 http://www.eubs.org/wp-content/uploads/2020/04/2020-0412-Position-of-the-BVOOG.pdf

3)      UC San Diego Guidelines for Evaluation of Divers during COVID-19 pandemic – 8^th May 2020
https://health.ucsd.edu/coronavirus/Documents/UC%20San%20Diego%20Guidelines%20for%20Evaluation%20of%20Divers%20during%20COVID-19%20pandemic.pdf

4)      European Underwater & Baromedical Society’s guidance on assessing divers – 21^st May 2020
http://www.eubs.org/wp-content/uploads/2020/05/English-EUBS-ECHM-position-on-diving-and-COVID-19-21st-May-2020.pdf

5)     UKDMC guidance and score card for assessing risk - 30th June 2020, updated February 2022. 
http://www.ukdmc.org/medical-conditions/coronavirus-covid-19/

All recommended that the diver would need to be symptom free and have regained their pre-covid level of fitness before resuming diving and usually after medical assessment

Summary of recommendations

# after full recovery                                              * Exercise test with oxygen saturation monitoring

The UKDMC took a different approach by designing a scorecard for divers to use, to assess their likely risk of having ongoing lung or heart damage. Points are issued for various symptoms, tests, hospitalisation, and assistance required for breathing, to give an overall score.

For those that only had mild symptoms for less than 7 days or asymptomatic disease they also have a points system to indicate who needs a Post Covid medical assessment, by one of their referees in their February 2022 update.

What might a medical assessment consist of?

Most diving doctors would recommend the following as a minimum:

·         Medical history questionnaire to identify significant medical problems

·         Review of any symptoms and duration

·         Clarification that full fitness has returned

·         Risk assessment of the type of diving planned e.g. holiday diving only, technical diving, remote locations

·         Review of GP / hospital records where appropriate

·         Annual blood pressure

·         Lung function tests

·         Exercise test with oxygen saturation monitoring

·         Those that required hospital treatment will probably need a chest CT scan and an echocardiogram as well

Fitness to participate in recreational activities may not be a local NHS priority and any tests required to establish fitness to scuba dive may have to be done, and paid for, in the private medical sector. They are likely to cost several hundreds of pounds.

HSE Guidance on validity of HSE diving medical certificates (MA2) for UK professional divers

In the UK instructors, divemasters & rescue divers working on commercial recreational diving courses must comply with certain legal requirements:

All divers must have a full medical in accordance with the requirements of MA1.

Additionally, under the Diving at Work Regulations 1997:

• divers must not dive in a diving project if they know of anything, including any illness or medical condition, which makes them unfit to dive; and
• under certain circumstances following illness or injury, divers must be re-examined by an approved medical examiner of divers (AMED) to assess their fitness to return to work.

Specific guidance (updated 9th May 2022) in relation to COVID-19 infection is provided below: 

So those who were truly asymptomatic or only had mild symptoms for less than 7 days can self-certify themselves as fit to return to diving after 7 days of being symptom free, all others will need an assessment by an AMED.

Further infection with Covid-19

A second or further infection with Covid-19 is very possible due to the mutation of the virus producing different strains. Although often this further infection is symptomatically mild, it cannot be guaranteed not to produce ongoing lung or heart damage, just because the prior infection did not do so. Therefore, further episodes of infection will need medical reassessment for fitness to dive.

Covid-19 vaccinations

Whilst there is no doubt that completion of vaccination courses does offer protection against severe illness, this is not guaranteed to protect against further infections. Therefore, vaccination status does not influence the advice on the need for medical assessment post Covid-19.

Summary

Covid-19 infection is common, potentially life threatening, risks ongoing ill health and increases the risk for scuba diving. Sadly, the consequences of a Covid-19 induced problem whilst diving are likely to be extremely serious and probably life threatening. Caution is required before divers return to diving, which should certainly not happen until completely symptom free and back to pre-covid levels of fitness. Thorough medical assessment is advised for the diver’s wellbeing. As diving health declarations may specifically ask about Covid-19 infection, many divers in the UK are likely to require medical sign off before diving. Failure to declare Covid-19 infection may invalidate insurance claims.

Medical services in the UK are likely to be very busy for the foreseeable future and less doctors are prepared to undertake sport diving medical assessments. This will inevitably result in delays in accessing fitness to dive medicals, so it is essential that the diver allows plenty of time to get medically assessed, before resuming diving, or booking a diving holiday.

Safe Diving.

Mark Downs. HSE AMED 01-13-09.                                                                                                                         Updated: March 2022