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The global prevalence of myopia has surged from 22.9% in 2000 to an estimated 34% in 2020 and is expected to reach 50% by 2050, affecting nearly 5 billion people — making it one of the most pressing public health challenges of the 21st century. Once regarded as a benign, correctable refractive error, myopia is now recognised as a progressive, potentially sight-threatening condition with significant socioeconomic consequences.

What is Myopia?

• Myopia — commonly known as nearsightedness — is a refractive error in which close objects appear clear while distant objects appear blurry.
• It occurs when the eyeball is elongated from front to back, causing incoming light to focus in front of the retina rather than directly on it. The longer the eyeball, the more severe the nearsightedness.
• Eye experts attribute myopia to a combination of hereditary and environmental factors. It typically begins in childhood or adolescence, worsening progressively until adulthood when it may stabilise.

The Scale of the Crisis

• Researchers predict that by 2050, 4,758 million people (49.8% of the world population) will be myopic, and 938 million will have high myopia — a severe form carrying significantly elevated risks of permanent vision loss.
• High myopia raises the risk of serious ocular diseases such as myopic macular degeneration (MMD), retinal detachment, glaucoma, and cataract — conditions that can cause irreversible blindness.
• Myopia's prevalence has dramatically increased in recent decades, now affecting as much as 88% of the population in some Asian countries — though its growing prevalence is by no means an exclusively regional trend.

Why is it Rising so fast? The "Changing Childhood" Factor

The sharp rise in myopia prevalence is strongly linked to urbanisation-driven lifestyle changes — particularly among children:

• Increased near-work activity: Prolonged screen time, reading, and digital device use force the eye to focus at short distances for extended periods — a key risk factor for axial elongation of the eyeball.
• Reduced outdoor time: Health officials increasingly highlight that children need more outdoor time as a countermeasure — natural light exposure and distant vision are believed to stimulate dopamine release in the retina, which inhibits excessive eye elongation.
• Earlier onset: As the number of people with myopia increases, the age of onset is decreasing — a critical concern since earlier onset leads to greater lifetime myopic progression and higher risk of complications.
• In South Asia, urban children show a 2–3 fold higher prevalence of myopia compared to rural children, predominantly due to increased near-work activity in urban school environments.

India's Burden

South Asia — comprising India, Pakistan, Bangladesh, and six other countries — hosts 23% of the world's population but bears a disproportionately large 30% share of global visual impairment. Uncorrected refractive errors, predominantly myopia, account for as much as 63% of visual impairment in the region — far exceeding the global average of 50%. India's rapid urbanisation, competitive education culture, and explosive growth in screen time among children are accelerating this trajectory.

Treatment and Prevention

• Corrective options: Glasses and contact lenses remain the primary correction tools. Negative (minus) powered lenses diverge light before it enters the eye, compensating for the elongated eyeball. Refractive surgeries (LASIK, PRK) are available for adults.
• Myopia control strategies — aimed at slowing progression rather than merely correcting existing refractive error — include orthokeratology (overnight contact lenses), low-dose atropine eye drops, and multifocal lenses. However, access to these therapies remains highly unequal globally.

The most cost-effective intervention remains behavioural: increasing children's daily outdoor exposure to at least 90–120 minutes and reducing near-screen time — a public health message with direct policy implications for India's school education and digital learning frameworks.