Why Water Safety Holds Hands With Pool Culture & Risk Assessment As Swimming Plans Revival

The Covid-19 Swimming Pool Study of Prof. Spica offers valuable guidance for programs planning a return to water - Images Courtesy: Myrtha Pools

Our helicopter over a comparison of water safety in 2019 and 2020 conducted with Professor Vincenzo Spica yesterday veers off and comes to rest on an outcrop affording us other angles on the issues swimming has to consider as it plans its revival in a season of postponement, cancellation and closure due to the COVID-19 pandemic.

So, Prof. Spica, with a nod to what we discussed yesterday, let’s pick up with this thought today in the second part of our talk: the sport of swimming around the world has taken the general view that elite athletes will be first back in the water in controlled environments. 

They have a job to do and, for Olympic teamsters and hopefuls, there are deadlines to meet after what for most has been the biggest layoff of their speedy swimming lives. The dates for championships, trials and other qualifying moments on the way to the purpose of it all, the Tokyo 2020 Olympic Games in 2021, are now largely known, at least tentatively.

The elite revival process has begun. While many elite athletes are back in the pool, others await news that their hopes of a June return to the water will be fulfilled.

covid19Siren cries of “open up! … it’s just a ‘flu; no danger here!” can be heard in the fray and spray of debate but the overwhelming message from swimming is this: pools can be model-safety places when it comes to elite sport. 

If certain controls – including numbers of athletes, distancing, disinfecting of equipment and related issues – are adopted to strengthen systems of hygiene and good pool practice that already make swimming one of the healthiest environments in sport, then the argument for keeping pools shut appears weak.

Junior, development and club-level swimmers face a steady, staged return that places pool and water safety first at a time when the pandemic is very much ‘live’. The timing of their return will depend on how effectively the controls and rules imposed on the few can be applied to the many; and on the direction of the pandemic.

Plans made public by several nations – the United States, Australia, Canada and several European nations in the mix – put a return to standard, mass swim-club/program practice at the back of the queue on a schedule of returns. 

Does that make sense? Says Prof. Spica:

“Yes, that would definitely be the correct approach but in some regards it depends on the facilities and programs. If they have a lot of space, they can manage with more people, so why would they need to reduce activity only to a specific group? “

He mentions elsewhere in our talk, the balance of budgets and the significance of funds available for extra cleaning and heightened safety measures at a time when revenue is likely to be challenging for many, to say the least. Prof Spica adds:

“So, all of this depends on circumstances. The professional athletes and coaches should be the ones who get to return first, of course. It is their job.

“We have to look at any situation involving high numbers as If it were a disco or a party without water. The same issues and views should be considered for pools.

Prof. Spica emphasises the need to regard “indoor and outdoor spaces” differently, while saying that “even in an outdoor space, distancing is an important aspect” of water safety and pool safety. He says: “If you have an outdoor space, probably you can allow a little bit higher number of people in the [venue] but still you must respect the social distancing. Whether more or less people can be added to pools in July, in August, now and so on, that depends on the situation of the pandemic in the country in question and prevailing regulations set there and with regard to the specific facility and event we’re looking at.”

We return to the key elements of the scene we saw from up in the helicopter:

Water Safety, The Pool & The Infrastructure & Practices Around It

The water, we’ll come back to. On the general environment, Prof Spica says:

“After the numbers and distancing, next is the area that includes things like the bar, meeting and gathering places, the spa and so on: these are actually even more risky than the area of the water. And the basic point is that the microorganism, from what we know so far, largely transmits through the air person to person and not through other ways, even if (those other ways) are possible, they haven’t really been described (with scientific accuracy). “

Transmission and other issues are discussed in this “Answering 20 Questions about COVID-19” session with Jay Butler, MD, Deputy Director if Infectious Diseases at the Centers for Disease Control and Prevention (CDC) – in April:

The “droplets” much spoken about when describing how COVID-19 is spread are not of the regular kind we associate with water but they are related to water safety and the pool environment. Whatever kind of droplet we’re talking about, none of them are new to the world.

Prof. Spica recalls the work of German bacteriologist Carl Flügge in 1899: he was the first to show that microorganisms in droplets expelled from the respiratory tract are a means of disease transmission. 

The ‘Flügge droplet’ was sometimes used for particles that are large enough to not completely dry out, roughly those larger than 100 μm.

Flügge’s concept of droplets as primary source and vector for respiratory transmission of diseases prevailed into the 1930s until William F. Wells differentiated between large and small droplets. He developed the Wells curve, which describes how the size of respiratory droplets influences their fate and thus their ability to transmit disease. 

Some of what is known of COVID-19 is not novel, in terms of coronaviruses in general and in the sense of the transmission traits it shares with other diseases, including ‘flu varieties. However, COVID-19 is a novel form of coronavirus, that fact among reasons why the world has been in lockdown as researchers travel a steep learning curve with a virus that has caused almost 370,000 deaths among 6 million infections worldwide since it emerged from China around the turn of the year. 

On the cusp of June, the United States now accounts for the largest numbers, not rates, at 1.8m infections (1.2m still active) and nearing 105,000 deaths since the first registered case around 10 weeks ago.

In swimming, when matters of water safety crop up, the tired mantra of “it’s just a ‘flu’ requires tired repetition of ‘no, it is not’. The good reasons include things that were pertinent in the parallel bygone world of the 1918 ‘Spanish ‘flu’ epidemic: no vaccine; no remedies; early days of research into how COVID-19 infection impacts long-term health differently in different populations.

Effectively, ‘the how, why and what do we do about it’ that are known for ‘flu and other respiratory diseases are not yet fully understood for COVID-19, that fact alone making caution the least of responses required, say experts far and wide.

Viruses spread by droplet transmission include influenza virus, rhinovirus, respiratory syncytial virus, enterovirus, and norovirus; measles morbillivirus; and coronaviruses such as SARS coronavirus (SARS-CoV-1)and SARS-CoV-2 that causes COVID-19. Bacterial and fungal infection agents may also be transmitted by respiratory droplets. By contrast, a limited number of diseases can be spread through airborne transmission after the respiratory droplet dries out. 

In addition, ambient temperature and humidity are known to affect the survivability of bioaerosols: as the droplet evaporates and becomes smaller, it provides less protection for the infectious agents it may contain. In general, viruses with a lipid envelope are more stable in dry air, while those without an envelope are more stable in moist air. Viruses are also generally more stable at low air temperatures.

The following Japanese report and film into research on transmission of COVID-19 delves deeper than the generic ‘droplet’. It discusses the probability that ‘micrometer particles’ could explain why infection appears to have taken place among people even where they did not come within a few metres of an infected person.

In one experiment, the droplets emitted from one cough in a room of 10 people survived in and spread through the air for 20 minutes, after which at least eight of those present would likely have been infected had the one person coughing been contagious:

A Warning From Bill Gates

Prof. Spica laments that “most coronaviruses have been totally neglected for years”, despite the SARS-CoV-1 (Severe Acute Respiratory Syndrome, 2003) and MERS-CoV (Middle East respiratory syndrome coronavirus, 2012) outbreaks and warnings that more would emerge, including this from Bill Gates in a 2015 TED Talk more than four years before the current pandemic unfolded:

In that talk, Gates says: “… we’ve invested very little in stopping an epidemic. We’re not ready for the next epidemic”.

How right he was. Prof. Spica picks up the theme when he notes:

“Everybody talks about these ‘droplets’. They were originally described at the end of the 1800s by Carl Flügge. So, now, with COVID-19, we ‘discovered the droplets’ but the world of public health has known about such things for more than a century. Also, the coronavirus has been around since the 1950s.

“Most coronaviruses have been totally neglected for years. I made a study in the 90s: I didn’t get 1 euro for doing the swabs related to that work. Now everybody wants to do the swabs. It is understandable in that no-one was caring too much about rhinoviruses or flu-like diseases.

“But then we got these two other forms, the SARS and the MERS and they changed the scenario. The SARS-Cov-2, which causes COVID-19, is different again and new. It has put everyone on the back foot. So, we have to be careful. That doesn’t mean that we have to be scared.”

COVID Learning Curve Not In Its Infancy & Must Be Travelled With Risk Assessment

covid19As Swimming World has noted, the SARS outbreak of 2003 did lead to significant research into coronaviruses: in 2008 a team at the University of Arizona raised questions about coronavirus survival rates in water, treated and untreated, while in 2009, a research paper from the University of North Carolina at Chapel Hill provides insight to the potential risks to open water swimmers and reasons why the sport’s authorities have needed to seek expert guidance on the way back to the water after lockdown.

In relation to the 2003 outbreak of coronavirus SARS-CoV, the paper states:

“The persistence of coronaviruses in water observed in this study suggests that if SARS-CoV should reemerge in human populations, water contaminated with these viruses may continue to pose an exposure risk even after infected individuals are no longer present.”

The learning curve now being travelled on water safety and the pool environment, however, suggests that such research efforts were never taken, in the decade since, to a place that the sport of swimming, for example, could now tap into for guidance during a coronavirus pandemic, albeit one involving a novel strain.

Could it be said that such research was “in its infancy”? Says Prof. Spica:

“Things changed a lot in the last weeks. So these papers are from years ago. Things have changed. Your question is not actually a scientific question in terms of peer review. It’s an operational question on an economic and political issue.

“It concerns regulations. The regulations start from the scientific evidence available but then they have to comply with actual reality. What I mean is that if I do an experiment in my lab here and I see that there is still one virus swimming around in there [the sample], I will say ‘it was not completely destroyed’. But if I have ‘one virus in I don’t know how many’ cubic metres of water, the point of view is not a point of view of science but is a point of view of assessing the risk.

“Assessing the risk that ‘that virus’ can arrive in the nose of ‘that person’. I’m over-simplifying but what we can say is that those research papers are useful but couldn’t be used [to form policy] because we didn’t have and we do not have even today a specific information on the specific and the strangest form of all the coronaviruses.”

Even so, that did not add up to research on water safety, viruses and risks being in its “infancy”, said Prof. Spica, because “we have some information from epidemiology”. He explains:

“We know this coronavirus can stay in the water and that it can resist in some conditions but we also know that we do not have, at least so far, any outbreak related to water. So, if water was a conduit for transmission, we would see something [a result of that. There is a good example from swimming pools. There is another virus that the W.H.O. allied two conditions too (for testing): non-faecal and faecal. This virus is called adenovirus.

“It can be transmitted through air or it can be transmitted through faeces. This is very important for pools because that is the agent for the transmission of conjunctivitis in swimming pools.”

The condition is also known as “Pink Eye” and “swimming pool conjunctivitis” because the infection is often spread in swimming pools. Chlorine in swimming pool water does not effectively kill the virus nor does it prevent the spread of infection.

“It is a more resistant virus,” says prof. Spica.

“It is a DNA virus and it can be transmitted both by speaking (in close contact) and through faecal contact. So for the COVID-19, we only have the hypothesis because we know that it can be released in the faeces. But we also know that it is a much more sensitive virus because it is an envelope virus … and should be less resistant.”

Couple to that the position taken on COVID-19 by health authorities, says Prof. Spica:

“In Italy, as in other European countries, and in USA the CDC, made some assessment on the risks and added the laboratory literature and research findings together with the risk when taking into account inter-personal (physical) distancing and [lockdown] measures and that, recently, made a big change to the circumstances we are in.

“We are not talking anymore just to about pure science or lab experiments; we are talking about decisions taken on regulations, based on science but considering the rules made taking into account the problem we face. A risk assessment has been made and can be applied to the situation.”

Water, water, every where, Nor any drop to drink – and best keep it that way

covid19And so we arrive at the water and hear cries of “Chlorine kills everything” in support of “Open Up! There is no danger in a pool!” Such attitudes seem to treat safety with the respect the Ancient Mariner showed the albatross in Coleridge’s classic, only to lament for ever more.

What’s wrong with those ‘Open Up!” statements, Prof. Spica? He cuts to the chase:

“From one point of view, it’s true that ‘chlorine kills everything’: related products were even used in war!”

  • In extremis: Chlorine is a toxic gas that attacks the respiratory system, eyes, and skin. Chlorine used in war required a concentration of 1,000 parts per million to be fatal. More than a million people were victims of gas attacks, not all of those using chlorine, in World War I. Many thousands of soldiers lost their lives from gas – chlorine and mustard gas the most commonly used – poisoning, while among those who survived, long-term health effects included chronic fatigue, memory loss, skin cancers, respiratory conditions, leukemia, several eye conditions, bone marrow depression and subsequent immunosuppression. Psychological disorders and sexual dysfunction were also factors, while chemicals used in the production of chemical weapons that found their way into the soil have been proven to cause cancer and have a deleterious effect on the brain, blood, liver, kidneys and skin.
  • In the swimming world we know: Chlorine is king of water safety. It is usually used, in the form of hypochlorous acid, to kill bacteria and other microbes in drinking water supplies and public swimming pools. In most private swimming pools, chlorine itself is not used, but rather sodium hypochlorite, formed from chlorine and sodium hydroxide, or solid tablets of chlorinated isocyanurates.

Chlorine reacts with the proteins in human hair and skin, the distinctive whiff associated with swimming pools not the result of chlorine itself, but of chloramine, a chemical compound produced by the reaction of free dissolved chlorine with amines in organic substances. As a disinfectant in water, chlorine is more effective than bromine and iodine in killing certain microbes.

Says Prof. Spica, with a nod to the extreme above and the water safety we all enjoy, as well as the nature of the bulk of applied research that has nothing to do with swimming pools: 

“It is really effective. But! Most of the studies have been done in a laboratory or in a process aimed at destroying a particular contaminant in, for example waste water or materials from a hospital. We can say that it is effective, definitely, but the concentrations in those cases are very different to those that we can have in a pool where there are people swimming.

“Chlorine’s effectiveness is also in the pool in the conditions (treatment protocols) that have been established (internationally) but even in those conditions, we cannot say that there are no risks. In the United States there have been outbreaks – and there still are – of Cryptosporidium (a parasite also know as “Crypto”).”

As CDC guidance notes: “The parasite is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it very tolerant to chlorine disinfection.”

“These are protozoa and there are some forms that are very resistant to chlorine. We know that a simple “one answer covers all” approach is wrong because nature doesn’t make the rules like that,” says Prof. Spica.

“So, regarding the coronavirus, we know we have disinfectant activity in the water and, as with cryptosporidium, if the pool is well managed, we consider the water to be safe.”

At the hysterical end of clamour to open up pools for summer season, there have been suggestions that if pool operators are in any doubt, they can just up the chlorine level to the upper end or beyond on the scale of accepted standards. Why, the context of water safety and health in general, would that be a bad idea? Says Prof. Spica:

“Whenever you use chlorine, it is effective because it reacts with other molecules. When it reacts will other molecules, it will make other compounds: hundreds of compounds. Some of these can be toxic. When we hear talk of increasing chlorine in the pool, we talk about small units but we are not talking about a huge range of units.”

Water Safety – A Success Story


Water, where awareness counts – Photo Courtesy: Craig Lord

Water safety treatment levels in pools already have a buffer built in. As Prof. Spica puts it: “… a balance in which you can have a healthy enough space but a safe space for the swimmer to be in”. That buffer is a compromise that reflects a play of ‘science meets risk assessment’; and accounts for the fact that treatment levels and related safety standards are, with a given range, slightly different the world over. 

Cultural and epidemiological conditions (for example, places where the risk of specific infections is higher than it would be elsewhere) contribute to differences between nations but “we are all within this same kind of larger range of portfolios”.

He notes, too, that drinking water has low levels of chlorine in it but describes pool water as “not what you would want to drink”. There is also chlorine sensitivity to take into account, some swimmers affected by normal levels of pool treatments, skin irritation and red eyes, while compounds that can result in getting the balance of chemicals in a pool wrong can be volatile. While some volatile compounds are detectable through smell, others are not, the potential harm hidden.

Prof. Spica agrees that water safety measures, including pool treatment standards, are a success story all around the world:

“An example of how much of a success story it is is that no-one is afraid of getting cholera or typhus in a pool these days. We cannot even imagine that but even that is a ‘possible risk’. It means that what we learnt works.”

And why more knowledge about the nature of COVID-19 is being chased down on an hourly basis somewhere in the world each day in the midst of the current pandemic.

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