A Government Technology Agency (GovTech) staff demonstrates Singapore's new contact-tracing smarthphone app called TraceTogether, as a preventive measure against the COVID-19 coronavirus in Singapore on March 20, 2020. - The mobile app using Bluetooth technology developed by GovTech in collaboration with the Ministry of Health informs user who had close contacts to confirmed coronavirus cases was launched in Singapore on 20. (Photo by Catherine LAI / AFP) (Photo by CATHERINE LAI/AFP via Getty Images)
How contact tracing could fight the coronavirus
01:33 - Source: CNN
CNN  — 

With much of the globe now under coronavirus-related restrictions, we have never been so tethered to our screens – for work, to connect with friends, to unwind or to distract ourselves.

One new estimate suggested that adults are spending more than 13 hours a day using screens, a spike up from 10 hours a day a year ago.

With children cut off from physically attending school, they are more reliant on laptops and tablets for online lessons and entertainment.

And with our new routines likely to have a lot more screen time for the foreseeable future, experts say it’s important to learn how to protect our eyes from suffering as a result.

While there is no evidence of long-term eye damage from extended use of smartphones, computer screens or other devices, prolonged use can sometimes lead to blurred vision, eye fatigue, dry or irritated eyes and headaches, according to Moorfield Eye Hospital in London.

Dr. Raj Maturi, the clinical spokesperson for the American Academy of Ophthalmology and a retina specialist, called these symptoms “digital vision syndrome.”

He, along with the doctors at the Moorfield Eye Hospital, recommended a 20-20-20 approach – for every 20 minutes spent at a screen you must take a break and look 20 feet in front of you for 20 seconds.

“When you are looking at a close target, your eyes are just training that one muscle at all time, and looking into the distance can relieve it,” he said.

While it’s close work, rather than screen use per se, that strains our eyes. Dr Maturi said that looking at bright devices can make us blink less, which leaves our eyes feeling dry.

“When things are bright, we blink less. It’s behavioral. So we can train ourselves to blink more often and blink fully,” he said.

If you’re already suffering from dry eyes, he recommended the use of artificial tears. Moorfields Eye Hospital also suggested using a humidifier, as well as making sure your work station is set up correctly.

The top of your computer screen should be in line with your eyes and about 18 to 30 inches from where you’re sitting and tilted back slightly, the hospital said in a blog post in April.

Dr. Rachel Bishop, a spokesperson for the National Eye Institute, agreed that where your screen is positioned is important.

“If you are looking down, then your eyelid is shut a bit and you’re not having as much evaporation – which can help prevent dry eyes. If you’re looking up high, your eye dries much quicker,” she said.

Other steps you can take include dimming the surrounding lights so that the screen is brighter in comparison and cleaning your computer screen regularly to avoid dust buildup, which can obscure the screen and cause eye irritation.

If you or your children continue to have vision problems after making these fixes, experts recommended seeking advice from an ophthalmologist or optician as it could be a sign of an uncorrected eye problem like long-sightedness or astigmatism.

If you’re older than your late 30s and unable to see an eye care professional because of lockdown restrictions, there would be no harm in buying a cheap pair of drugstore reading glasses and seeing if they help, said Bishop.

“The focusing muscle in your eye changes as you age. You can focus up close when you’re 20 for hours at a time and have no problems. But that ability declines as you age,” said Dr Bishop.

“For people who aren’t eager to have a medical appointment, the first thing is to try on some low-strength, over-the-counter reading glasses. Hold up something to read and pick the lowest number you can comfortably read at the distance you like to work,” she said.

Blue light

Another potential concern is the “blue light” that digital devices emit, but Dr. Maturi said this affects our body clock, rather than our vision. But it’s something worth paying attention to – especially for kids who can get overstimulated easily.

“When we go outside we look at a blue sky, that’s blue light,” he said. “The issue with blue light is at night. It can delay your ability to sleep quickly,” he said.

He suggested that people turn their devices to night mode or use e-readers with screens that more closely resemble a physical book. The key was to look at how many nits a display had – a measurement of luminance or brightness, he added.

To protect kids’ eyes, parents should encourage them to spend as much time outside as possible – within restrictions that are in place where you live to prevent the spread of Covid-19.

The past two decades have seen a massive increase in myopia or short-sightedness among children – and while scientists can’t agree on exactly what has caused this rise and whether there’s any link to screen use, they do know that spending time outdoors, especially in early childhood, can slow its progression.

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“We should know more in a few years when research comes up with more answers, but for parents they have a dilemma because the school is now brought into the screen and kids social engagement are now brought into the screen and kids are playing their games on a screen,” said Bishop.