Republish

We encourage you to republish this article online and in print, it’s free under our creative commons attribution license, but please follow some simple guidelines:
  1. You have to credit our authors.
  2. You have to credit SciDev.Net — where possible include our logo with a link back to the original article.
  3. You can simply run the first few lines of the article and then add: “Read the full article on SciDev.Net” containing a link back to the original article.
  4. If you want to also take images published in this story you will need to confirm with the original source if you're licensed to use them.
  5. The easiest way to get the article on your site is to embed the code below.
For more information view our media page and republishing guidelines.

The full article is available here as HTML.

Press Ctrl-C to copy

Fresh perspectives and low-cost technologies are key to tackling visual impairment, writes Gareth Willmer.

When a country is in the grip of a major epidemic or struggling to tackle life-threatening diseases, persuading them to focus on eye health may be a tough sell.

But visual impairment affects at least 2.2 billion people, according to the first ever World Report on Vision published in October 2019 by the World Health Organization (WHO), with low- and middle-income regions bearing the greatest burden.

According to the report, 1 billion or more of these cases could have been prevented or corrected, despite the fact that many of them can be solved with glasses or simple treatments.

“The problem has been looked at through a different lens. For the last 30 years we’ve been talking about blindness, but now we’re talking about vision,”

Andrew Bastawrous, co-founder and CEO, Peek Vision

Significant progress has been made in treating diseases such as trachoma, the world’s leading infectious cause of preventable blindness. However, ageing populations and urbanisation are raising the prevalence of other impairments, while a growth in diabetes is increasingly leading to sight problems or blindness in regions including Asia and Africa.

“As populations tend to grow, we’ll see more of these conditions,” says Imran Khan, chief global technology lead for policy and programme strategy at the charity Sightsavers. “And as we move away from infectious causes of blindness like trachoma to more of the non-communicable diseases [NCDs], we need to engage with a wider health agenda.”

In its Vision 2020 programme set out in 1999, the WHO targeted eliminating avoidable blindness by next year, but Stuart Keel, technical officer for blindness prevention at the WHO, admits there is a long way to go.

“The distribution of vision impairment is inequitable,” he says, despite “enormous progress” over the past 30 years in treating and reducing blindness from infectious eye conditions such as trachoma and onchocerciasis, or river blindness.

The WHO’s figures show that cases of distance vision impairment are four times higher in many low and middle-income regions than in high-income regions, while blindness in areas of sub-Saharan Africa and Asia is eight times higher.

Eye care needs to be better integrated into overall national health schemes, says Keel, pointing out that the two have often been viewed separately even though there is frequently crossover, such as between diabetes and eye disease. He cites the case of India, where there has been a marked reduction in blindness in the past decade with the inclusion of eye care packages in health insurance schemes.

Scale of the problem 

James Chen, who set up sight charities Vision for a Nation and Clearly, points to the wider definition of impairment that has emerged – which he believes has painted a truer picture of the extent of the problem.

He cites previous global estimates that claimed there were just 300 million visually impaired people, compared to the WHO’s 2.2 billion figure, adding: “Now, I think, the eye sector and the world understand the scale of the issue.”

There is a growing recognition that sight problems are not just about health, but have major social and economic implications, especially as countries seek to achieve the sustainable development goals (SDGs). “How can the world community deliver on the SDGs if one-third of the world’s population have uncorrected poor vision?” asks Chen.

In a Clearly-backed study published last year (2018) of tea pickers in Assam, India, productivity among those aged over 40 with presbyopia — age-related decline in near vision — surged 22 per cent when they were given glasses, rising to almost a third among those aged 50. The organisation hopes that evidence like this will persuade governments to boost eye care amid competing priorities.

Another initiative, by Vision for a Nation, led to Rwanda becoming the first low-income country to deliver universal eye care by early 2018. In collaboration with the Ministry of Health, more than 3,000 nurses were trained to provide simple sight tests, glasses and eye treatment, and visited all of the country’s 15,000 villages.

Better resources and tools

The solution was not 100 per cent perfect, admits Chen, with nurses trained to do a “good enough, not perfect, vision screening”, but improvements were large-scale. Similarly: “The glasses we handed out weren’t as perfect as you would get in London or Hong Kong, but functionally they allowed you to have better visual acuity.”

Now Clearly is advocating for similar projects in all developing countries. “If we do it one country at a time, we’re not going to get that far,” says Chen.

Fortunately, advances in technology are making things cheaper and easier. Through Chen’s commercial venture, Adlens, it has been possible to make glasses with lenses that can be adjusted to fit different wearers for a cost of US$1.50, he says.

The non-profit organisation Global Vision 2020 has also sought to minimise costs in low-resource settings through its simple, lightweight USee vision-screening tool and lenses that snap in and out of frames.

Kevin White, the organisation’s founder and executive director, says: “The way I approached it was that we’re never going to produce enough eye health professionals to solve all of the problems.” Instead, he said the question was: “What can we give to a lower echelon of care that’s still ethical, still efficient and still provides a good product in a way that’s sustainable?”

School focus

Integrating eye health into the school environment to target children is one way of ensuring sustainability, advocates say. Catching milder eye conditions at an early age can help prevent them spiralling into graver problems further down the line.

“By framing eye health as a larger part of a health or education agenda, you’re able to gain more traction,” says Khan at Sightsavers, which is working to combine vision screening with a deworming push in schools.

The initiative began with a pilot in 2016 in Cambodia, Ethiopia, Ghana and Senegal, before a three-year programme was launched in Liberia at the end of last year to train 2,400 teachers to provide screening and distribute deworming drops. In one county in Liberia, says Khan, 11 children with cataracts were identified through the project.

Peek Vision similarly sees the classroom as a key battleground for tackling the problem. Harnessing the growing ubiquity of smartphones, the eye care company has produced an app that teachers can use to test children’s sight. Parents then receive results by automated SMS or voice messages, and the system can track how frequently children referred for treatment turn up and whether treatment is effective. “It allows more data-driven decision-making so people can see, in real time, the effect of their decisions,” says Andrew Bastawrous, co-founder and CEO of Peek. “Our role is creating visibility around those who are falling out and being left behind.”

Other technologies also have potential. Drones have been used by the start-up Zipline to deliver emergency medical supplies to hard-to-reach areas in Rwanda and Ghana, including blood and vaccines – and Chen is exploring whether this could be used to drop in glasses too.

Artificial intelligence also shows promise, but is not yet adopted in routine clinical care, says the WHO’s Keel, adding that there are still ethical discussions to be had in adopting these technologies.

In eye care as a whole, there is still lots to do, says Bastawrous, with only really the “top of the pyramid” so far addressed. But changes in the framing of the issue can help to move things forward with a more “people-centred” approach, he says, with increasing acknowledgment of the social and economic benefits of improving vision.

“The problem has been looked at through a different lens. For the last 30 years we’ve been talking about blindness, but now we’re talking about vision,” he says.