This Saturday, June 8, is World Oceans Day. On this occasion, 20 minutes offers you a series of articles, videos, reports, etc. entitled “20 Minutes Under the Sea”.
As part of this series, and as the summer season approaches during which many French men and women will go on vacation to the seaside and take advantage of the summer to swim, 20 minutes looks at the risks associated with swimming water for the eye health of contact lens wearers. Sea, ocean, swimming pool, lake, river and even tap water: if these waters come into contact with the eyes when wearing lenses, you increase your risk of developing a severe eye condition: infectious keratitis. How to protect yourself from it? And what should you do if you think you have contracted it? 20 minutes explains to you.
“A bell-bottom effect”
What is infectious keratitis? “It is an inflammation of the cornea, which is the transparent lens on the surface of the eye and which protects the iris,” replies Dr. Thierry Bour, ophthalmologist and member of the Office of the National Union of Ophthalmologists of France (SNOF). The infection is caused by a pathogen: fungus, virus or bacteria. And when we wear lenses, we are more exposed to the risk of contracting amoebic keratitis, caused by amoebae: parasites present in feces, but also in water.
Amoebic keratitis is “a rare eye infection located at the cornea and causing painful lesions,” explains the Rothschild Foundation Hospital. It appears in most cases in people who wear contact lenses and who bathe or shower with them. This disease impairs vision.
In practice, “the amoebae will reach the eye through a prolonged contact mechanism: normally, in the event of contact with the eye, they are chased away by blinking and tears,” explains Dr. Bour. On the other hand, if you wear lenses, amoebae will tend to attach themselves to the contact lens, and thus find a favorable environment for their development. After having contaminated the lens, they will find themselves in direct contact with the eye, the lens here having the effect of placing the amoebas in the eye. From then on, they will succeed in penetrating the cornea and causing a serious infection.”
Be careful even with tap water
Are contact lens wearers at risk with all bathing waters ? “The more contaminated the water, the greater the risk of developing infectious keratitis,” indicates Dr. Bour. The risks are higher in fresh water: swimming pools, in rivers, lakes and ponds. This happens less frequently in the sea or ocean due to the high salinity level and the large volume of water churned. In this case, there is above all a risk of eye irritation due to salt and sand, although infection remains possible.”
But also be careful with tap water! “Amebic keratitis mainly affects people who clean their lenses with tap water or who shower with their contact lenses on,” warns the ophthalmologist. However, in tap water, a certain level of amoebae – very low – is tolerated. Normally, at such low concentrations, it is not likely to cause eye infections, unless you wear contact lenses.”
This is precisely what happened at the beginning of 2022 to Marie-Sophie Lacarrau, presenter of the 1 p.m. news on TF1, away from the sets for almost five months due to amoebic keratitis in the right eye contracted in taking a shower with her lenses. A bad experience which pushed the journalist to communicate about this avoidable condition which severely affected her cornea.
Early treatment to avoid after-effects
However, “amoebic keratitis is rare, around a hundred cases per year,” emphasizes Dr. Bour. But what is problematic is that it can contaminate both eyes, it often affects young people and can cause serious infections that risk leaving vision damage, or even requiring a corneal transplant. The long-term impact can be significant.”
Amoebic keratitis causes “pain upon exposure to bright light (photophobia), red eyes, excessive tear production, a feeling of sand or broken glass in the eyes, before causing problems with vision. view,” explains Rothschild Foundation Hospital. “Hence the importance of consulting as soon as possible to be taken care of in time,” adds Dr Bour. If you have red eyes and discharge from your lenses, this is not normal, the first thing to do is to remove them, do not put them back in and consult. However, the diagnosis is not easy to make because the symptoms are not very suggestive: it starts with a little discomfort and pain which is not major at first.”
To make the diagnosis, “the ophthalmologist must take a tissue sample from the cornea which he will then observe under a microscope and culture,” explains the Rothschild Foundation Hospital. “The advantage of early diagnosis,” recalls Dr. Bour, “is that we have very effective disinfectant treatments against amoebae. But the treatment, which is quite heavy, must be taken very early to be effective. However, patients often delay consulting, especially since the signs are not very suggestive: discomfort, and pain which is not major at first, then it degenerates.”
Good hygiene for your lenses
Hence the importance of having perfect hygiene with your lenses to protect yourself from the risk of keratitis. “In most cases, it is linked to the use of tap water to clean the lenses,” insists the ophthalmologist. However, you really need to ensure the hygiene and maintenance of your lenses with suitable products. And it is important to rinse well and let the cups in the case dry during the day, and thus prevent it from turning into culture broth. Important detail: wash your hands with soap and water before handling your lenses, whether to put them in or take them out.
Our 20 Minutes Under the Sea file
Obviously, we no longer take a shower with our lenses. And, for those who cannot do without lenses when going bathing and swimming, “the best thing to do is to wear waterproof swimming goggles, and to wear single-use lenses for swimming to avoid all risks.