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Microbial Contamination and Contact Lenses: Reducing Risks for Swimmers

2 CPD in Australia | 0.25G in New Zealand | 5 October 2017

By David Stephensen

This is Australia. Summer is coming… This season, 60 per cent of contact lens wearers will jump into the pool or ocean without removing their contact lenses and without wearing any form of barrier between their lenses and the water.1,2,3 How can you, as a practitioner, identify those patients and provide the education they need?

The warm air wafted gently across his face as he stepped off the concrete, bracing himself for the shock of the hot, dry sand on the soles of his feet. The sand hadn’t bothered him as much when he was younger and lived by the beach, but now that he was living the inner-city dream of twelve-hour work days he didn’t venture into the great outdoors as often as he used to do.

Pushed onwards by the smell of salt air and the sound of waves rolling onto the shore, he danced his way forward over the dune and onto the beach proper. Pausing only as long as he could tolerate the heat, he looked up and down the beach. The crowds had not yet arrived for the day, the surf was a clear, radiant aqua in colour, with just the right amount of swell for a good swim. He hadn’t had a holiday in a long, long time and he was looking forward to the reward of diving into the cool, clear ocean and tasting the salt on his lips. He stepped forward, walked down to the cooler, wet sand and dropped his towel along the high tide mark. Looking out at the water, he was pleased to see he could read the surf conditions easily. The new contact lenses his optometrist had prescribed for him really were a lot clearer and more comfortable than his previous contact lenses. Full of the flush of youthful reminiscence he ran towards the water’s edge.

Throwing Caution to the Wind

She looked carefully up and down each leg, then each arm. Shaking her head, she saw she had missed some patches and reached across the picnic table to grab the sunscreen bottle. She checked her shoulders and realised she had forgotten to put sunscreen there as well. It was so much easier to check these areas with her contact lenses on.

The glasses she wore at home to get ready were so old these days that they were barely enough to allow her to see to get to the bathroom from her bedroom. Obviously, the spectacles were now also not sufficient to see as far as her feet when putting sunscreen on.. She sighed, thinking she really should update her spectacles at some stage, then winced as the cold sunscreen hit her sun warmed skin. Once she was certain she had covered her fair skin completely with sunscreen, she put the bottle back down and looked up from the picnic table. This was only her second time water skiing with her new boyfriend, but she had enjoyed the first time so much that she had readily agreed to try again. Her concerns about falling and injuring herself had become secondary to the exhilaration of the speed and thrill of achievement.

The view across the lake blurred and she blinked several times to clear her vision. She had just opened a new pair of contact lenses and didn’t want to risk losing them so she had kept the last pair after the end of the thirty days in some disinfecting solution. She would use them today and discard them tonight. She recalled her optometrist advising her to get some daily disposable contact lenses to use water skiing, but the cost of buying those on top of her monthly disposable contact lenses was too much for one pay period. Maybe, before the next water skiing session, she would buy a couple of boxes of the daily disposable contact lenses – her optometrist had seemed quite concerned about her eyes and the monthly disposable contact lenses while water skiing. She couldn’t quite recall why as her thoughts were broken by the sound of her boyfriend calling her down to the water’s edge. She stepped ahead, looking forward to the day on the water.

Seeking the Competitive Advantage

Chlorine wafted across from the cool aqua water of the swimming pool, the sunlight glistening off the surface and striking him right in the centre of his vision as he pulled off his sunglasses. He winced and blinked a few times to acclimatise himself to the light. The only problem now was that he couldn’t see a thing without wearing his prescription sunglasses.

He sighed and sank down onto the brightly painted wooden bench a few rows back from the pool deck. Tucking his prescription sunglasses carefully into their case, he reached into his bag and pulled out some alcohol based hand sanitiser and a pair of contact lenses. He hadn’t played water polo often since he was a kid, and now, in his early thirties, he was a lot more shortsighted than he was back then. That meant trying to play without vision correction was not an option.

He supposed he should look at getting some prescription goggles, but trying to find a pair suitable for water polo that also could carry a spectacle prescription just seemed too hard a task to undertake when he already had contact lenses he could wear. He double checked that he had another two or three spare pairs and was secretly glad that he had switched to daily disposable contact lenses. It wouldn’t be a first if he had to dash out of the water to replace a lost contact lens during a game. He splashed some of the hand sanitiser on his hands and rubbed them together until it evaporated away and then inserted his contact lenses. The match before his finished and his teammates were calling him down to the pool deck. Sighing, he tucked his bag under the bench, checked his vision in each eye, then started walking down the concrete stairs to the pool deck.

Stepping In to Help

It might have been the sound of the seagulls squawking that raised her from the magical place that her book had been taking her. Reading was a great escape from the realities of life although she had to admit, as she shook her head and looked around. Life wasn’t too bad today. The added bonus was that with her new multifocal contact lenses, she was able to sit and do the things she found most pleasurable without having to wear her sunglasses over her reading glasses, as she normally did when coming to the beach.

Alone in the tent, she felt a very small twinge of guilty pleasure in realising she had been so comfortable that she hadn’t noticed her daughter had taken the grandchildren down to the water.

Easing herself up in the chair, she scanned the crowd bunched between the flags looking for her daughter and three grandchildren. Once she found them, she quickly saw her daughter was not having the same relaxing time.

The twins were splashing at the edge of the water, not old nor confident enough in the water to venture too far into the surf. Their older brother was confident enough though, and she could see her daughter’s tense posture as she tried to keep the twins from wandering too far from her feet, then turned to yell at their brother not to go too far out into the waves without her.

She recalled her optometrist emphatically telling her not to swim in her contact lenses as this increased the risk of her having an eye infection. She’d also been advised water contained parasites that could send her blind. She hadn’t been too bothered by this information as it gave her the perfect reason not to have to swim, an activity she didn’t particularly enjoy as much as a good book. She figured that standing by the water’s edge watching the twins while they splashed around would free up her daughter to enjoy a proper swim with her son. She wouldn’t be swimming, so there shouldn’t be a problem wearing her contact lenses. Standing up she grabbed her hat and made her way down to the water’s edge.

Taking the Plunge

Cold beer, hot sausages on bread and a warm summer’s day in the backyard. It couldn’t get much better. He looked down at the barbecue and smiled, satisfied that he had made it clean enough after cooking lunch for everyone. Time to relax. He closed the lid of the barbeque and put the cover on. Looking around, he saw almost everyone had made their way down to the pool. They were right, it was time for a swim. He pulled off his hat, t-shirt and sunglasses and put on a long-sleeved swim shirt for sun protection. He smiled, thinking about the way his optometrist had carried on about the UV protection in his daily disposable contact lenses. Braving the blisteringly hot pavers, he made his way to the pool gate. Slipping the latch and easing it open, he saw no-one was in the deep end at the moment. While a bomb dive would be a little anti-social he really couldn’t resist…

Identifying the Risk-Takers

These are five examples of typical activities on or around the water that patients are likely to undertake during an Australian summer. Surveys of patients’ behaviour wearing contact lenses indicate that of the five contact lens wearers described in these scenarios, three of them will actually go ahead and wear their contact lenses in the water, or 60 per cent of contact lens wearers. Some studies indicate that the majority of them will do so without wearing any form of barrier between the contact lenses and the water, such as well fitted swimming goggles or a diving mask.1,2,3 So can we as practitioners identify the patients who are most at risk or will be non-compliant?

In a large study of an Australian contact lens wearing population, what was also apparent was the diverse range of bodies of water into which contact lens wearers wore their contact lenses during participation in water sports. Oceans, rivers and lakes accounted for 29 per cent of water sports, public swimming pools accounted for 30 per cent of water sports, and private swimming pools accounted for 26 per cent of water sports.2 Swimming in contact lenses has been associated with an increased risk of microbial keratitis. The Centre for Disease Control (CDC) in the United States of America specifically associates wearing contact lenses during water sports with Acanthamoeba keratitis and recommends not wearing contact lenses during water sports.4

The majority of contact lens manufacturers and optical companies also specifically advise against wearing contact lenses when swimming. This advice is primarily that abstinence from wearing contact lenses during water sports is the appropriate course of action, while some do mention using swimming goggles or discarding single use contact lenses after swimming. To an extent, these manufacturer and corporate advices may be considered confusing to patients as they contain both advice for absolute abstinence, while offering alternative scenarios that allow some measure of permissiveness.5,6,7

Professional bodies provide similar public advice, although tend to discuss more the option of wearing tight fitting goggles to reduce the risk. The need to discard daily disposable contact lenses immediately after swimming, and to clean and disinfect other forms of contact lenses with fresh solution, is also presented.8.9

Understanding Non-Compliance

The tendency for patients to wear their contact lenses during water sports despite advice to the contrary from practitioners, professional organisations, manufacturers, and government health agencies represents a form of non-compliance. It is relevant then, to look at what factors may come into account when considering which patients may be more likely to be non-compliant.

Studies on this topic have demonstrated remarkably few demographic characteristics that may be associated with predicting which patients may be non-compliant. Socioeconomic status, education levels, occupation, gender and  a history of previous contact lens related complications are not predictive of non-compliance.

A patient’s health beliefs do not reflect their compliance levels with contact lenses, nor does their level of satisfaction with the care provided by their optometrist. Consequently, the practitioner should avoid pre-supposing which patients are more likely to be non-compliant and assume that any contact lens patient may wear their contact lenses during participation in water sports.3 In the earlier hypothetical case examples, it can be seen that for many people, the decision to wear contact lenses during water sports may be a result of factors that make them feel happy and they may act without regard for practitioner’s advice. So, what would happen when contact lenses are worn during water sports?

The Consequences

From investigations carried out, we know that contact lenses do attract bacterial deposition when worn during swimming. In a study undertaken in a chlorinated, filtered swimming pool that had not been used prior to the study group on the day, the swimming group of contact lens wearers demonstrated a significantly increased amount of bacterial deposition compared to a non-swimming control group.10 Additionally, swimming goggles have been shown to provide a degree of barrier protection against bacterial deposition while swimming. In a study conducted in an ocean-fed swimming pool in Australia, using swimming goggles that were sealed for one eye and open for the other, the sealed eyes showed significantly less bacterial deposition on the contact lenses than the open eye. This study also showed that there was no association between the bacterial levels in the pool water per se compared to the bacterial levels detected on the contact lenses.11

Swimming and Acanthamoeba spp Keratitis

The significant association between swimming and Acanthamoeba spp keratitis is a primary concern in contact lens wear during water sports. While Acanthamoeba keratitis is rare, at between 1-33:1,000,000 contact lens wearers per year in the USA, the consequences are significant.4 One interesting case report described the capacity for Acanthamoeba spp to colonise the bacterial biofilm in a contact lens storage case and proliferate in that environment. Consequently, it may also be the case that the onset of a serious microbial keratitis may be commenced by exposure during water sports to microorganisms, but then facilitated in the coming days or weeks by poor compliance with cleaning and disinfection regimens.12 A recently published case series of Australian episodes of Acanthamoeba keratitis managed at the Royal Victorian Eye and Ear Hospital found a high rate of contact lens wearers, with 31 out of 34 patients affected being contact lens wearers. However, in this case series, only six of the contact lens wearers admitted participation in water sports wearing their contact lenses.13 Over-wear of contact lenses was a more frequent risk factor. While Acanthamoeba keratitis is clearly associated with water sports, the incidence is very low.

Microbial Keratitis

Having canvassed the issues associated with bacterial contamination of contact lenses during water sports, and the association between swimming and Acanthamoeba keratitis, it is then interesting to look at what place swimming has in terms of being a risk factor for microbial keratitis generally. In 2008, two prospective studies looking at the incidence and risk factors for microbial keratitis were published. One study was conducted over a twelve-month period in Australia, and the other over a two-year period in the United Kingdom. In neither study did swimming in contact lenses rank as a major risk factor for microbial keratitis.14,15 This is somewhat interesting given the level of strong advice against swimming in contact lenses provided to the contact lens wearing public. A further study looking at the development and evaluation of evidence-based guidelines regarding contact lens-related microbial keratitis, demonstrated that practitioners had a good understanding that swimming in contact lenses was a risk factor for microbial keratitis. This study reported that swimming in contact lenses carries a relative risk of 5.5 times that of not swimming in contact lenses. However, this should be taken in context of other activities that carry higher levels of risk. For example, the act of going on a holiday and wearing contact lenses has been calculated to carry a 15.1 times relative risk of microbial keratitis compared to not wearing contact lenses. Yet contact lens manufacturers, professional organisations and government bodies do not present the same advice for abstinence with respect to wearing contact lenses while on holidays than is offered for contact lens during water sports.16

Perhaps what it is that we are concerned about as practitioners, with respect to contact lens and water sports, is not that there is a significant incidence nor unusual increase in risk compared to other activities associated with contact lens related keratitis. Instead, we appear to be concerned with preventing the rare but serious consequences from infections such as Acanthamoeba keratitis. This is a justifiable concern in the mind of the practitioner, but despite the various forms of communication to the public, the rare incidence of these serious infections does not appear to outweigh the effects on quality of life that not wearing contact lenses during water sports would have in the minds of the general public. This, then, is what leads them to non-compliance in their everyday life.

The Final Word

Advocating abstinence from pleasurable activities has not had a good track record over the course of human history. Perhaps as practitioners we should, within our own professional judgement, be entertaining a more worldly-wise view with respect to the advice we give to our contact lens wearing patients.

As practitioners, we need to consider what our patients may independently decide to do when they leave the consulting room. The hypothetical cases presented at the start of this article were not offered as hollow stories, but to provide reasonable examples of situations in which the average contact lens wearer may engage in water sports.

Can we really foresee these situations when the patients are sitting in our consulting room? Could you pick which of those three of the five patients in the earlier hypothetical case examples would still enter the water instead of turning away and removing their contact lenses or abstaining?

Should we be taking the lead and providing a broad range of education, advice and options to our contact lens wearing patients?

Avoiding swimming with contact lenses is clearly the best method of avoiding an increased risk of microbial keratitis. However, in the face of the high level of non-compliance, only providing advice that recommends abstinence, may induce unwanted consequences if patients are not aware that they can reduce their risk of microbial contamination of their contact lenses through the use of barrier protection, such as swimming goggles. 



David Stephensen B.App.Sc(Hons)(Optom) B.Bus Graduate, Certificate in Ocular Therapeutics, CASA CO conducts a specialty contact lens practice with his primary practice located in the southside Brisbane suburb of Moorooka. Dr. Stephensen is a Fellow of the Cornea and Contact Lens Society of Australia and is now a Honorary Vice President of the Cornea and Contact Lens Society and the Chair of the Case Report Section for the Fellowship programme. He has interests in anterior segment eye conditions, toric intraocular lenses, contact lens correction for presbyopia, orthokeratology and in contact lens correction of abnormal corneas – particularly pellucid marginal degeneration, post graft, and keratoconus.

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15. Dart JKG, Radford CF, Minassian D, Verma S, Stapleton F, Risk Factors for Microbial Keratitis with Contemporary Contact Lenses – A Case Control Study, Ophthalmology, 2008, 115(10):1647-1654
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This article was sponsored by Basuch & Lomb. © 2017 Bausch & Lomb Incorporated. ®/TM denote trademarks of Bausch & Lomb Incorporated and its affiliates. Other product names/ brand names are trademarks of their respective owners. Bausch&Lomb (Australia) Pty Ltd. ABN 88 000 222 408. Level 2, 12 Help Street, Chatswood NSW 2067 Australia. (Ph 1800 251 150) LOTJ n: 2017-08-039

' Consequently, the practitioner should avoid pre-supposing which patients are more likely to be non-compliant and assume that any contact lens patient may wear their contact lenses during participation in water sports '