Blog post

Blindness: an opportunity for effective giving?

6 min read
Sep 1, 2014
This article is a summarised form of an upcoming report by Josh Goldenberg on the topic of blindness. Keep an eye out for when the report is published for further details of this area.

Blindness and visual impairment are significant issues worldwide, causing loss of employment, self-esteem and productivity. The most recent estimates from PwC state that 32.4 million people worldwide are blind, and 190.6 million suffer from low vision. Out of these, 1.4 million children are blind, and 19 million visually impaired. This is down from the 37-38 million people living with blindness in 1990, suggesting progress, and a rapid decline in blindness rates.

90% of visually impaired people live in the developing world, in large part their blindness caused by easily preventable conditions such as trachoma-induced cataracts and river blindness caused by blackflies. An astonishing 80% of visual impairment in the world could be prevented by good hygiene and basic medical care. This makes blindness an attractive candidate when looking for a particularly effective charity.

PwC estimated that it would take $392bn (on top of the current $5.9tn) from 2011-2020 to eliminate avoidable blindness entirely, though only $128.2bn to eliminate avoidable blindness in the low and middle income countries. As we know, for the cost of one guide dog, over a thousand surgical treatments for trachoma could be provided. But does this yield any specific steps we can take to make an impact on blindness? Below is what you need to know.

Types of blindness

Cataract

Cataract is responsible for at least 33% of global visual impairment and at least 51% of global blindness, according to the WHO. It is clouding of the lens of the eye which prevents clear vision. Overall, the cost-effectiveness of surgery in the South Asia region has been estimated at about $60 per disability adjusted life year, and an analysis of the current literature on cataract prevention suggests that the most likely figure is somewhere around $40-150, with $90/DALY around the median of each of the estimates, a figure promising enough to be worth investigating further.

Despite the very promising numbers, cataract treatment requires a lot of factors to be in place before it can start to be effective. A lot of training is required for the surgeons who carry out the treatments, as well as assistance from health providers, and education if the community to dispel fears of surgical treatments. Compared to deworming, it requires a much greater investment of time and money, but fewer people are needed, and surgeries need only be administered once, rather than yearly.

Although we can’t be confident that donating to combat cataracts is as effective as donating to our top charities, it is likely that it will be a very effective investment.

Trachoma

Trachoma is the result of infection of the eye with Chlamydia trachomatis. If the infection is left untreated and the eye is re-infected, it can cause the eyelid to turn inwards, meaning that eyelashes come into contact with the eye, causing scarring, immense pain and eventually irreversible blindness. The WHO recommended strategy for combatting trachoma is ‘SAFE’ – surgery, antibiotics, facial cleanliness and environmental changes.

Despite the multifactorial approach recommended by the WHO, surgery is the best investment for donors at the moment, as it is not subject to the same limitations as the other factors: Antibiotics are mass-distributed, facial hygiene interventions involve mass education, and environmental change involves large projects, such as improving sanitation. Funding surgeries has the potential to make way for many future operations (such as hospital building) and it is also a necessary part of an eradication programme.

A 2012 WHO article on the situation of trachoma paints a positive picture on the current state of affairs regarding this disease. From the 53 countries that are endemic in blinding trachoma:

  • 28 reported data on implementing the SAFE strategy.
  • 6 countries reported that trachoma was no longer a public health problem in 2012 (<0.1% suffer from trichiasis, <5% of 1-9 year olds suffer from active trachoma).
  • The number of people living in trachoma endemic districts reduced from 317m in 2010 to 241m in 2012 – almost a 25% decrease in just two years.
  • 48.8 million people received antibiotics.
  • 169,000 trachoma surgeries were carried out.

A 2006 estimate also stated that the number of people affected by trichiasis fell from 360m in 1985 to just 80m in 2006. So great progress is being made.

Onchocerciasis

Onchocerciasis is responsible for 0.8% of global visual impairment (1.5 million) and 4% of blindness (0.6 million). It is also regarded as particularly painful and debilitating. To quote the WHO’s pleasant description:

“Onchocerciasis is a parasitic disease caused by the filarial worm Onchocerca volvulus. It is transmitted through the bites of infected blackflies of Simulium species, which carry immature larval forms of the parasite from human to human. In the human body, the larvae form nodules in the subcutaneous tissue, where they mature to adult worms. After mating, the female adult worm can release up to 1000 microfilariae a day. These move through the body, and when they die they cause a variety of conditions, including blindness, skin rashes, lesions, intense itching and skin depigmentation.”

Cost effectiveness estimates range from 4 to 130 $/DALY. More work is needed to come to a more confident conclusion about the effectiveness of interventions in this area.

Other forms of blindness include corneal opacities, glaucoma, diabetic retinopathy, age related macular degeneration, and childhood blindness.

Charities

The charities investigated are ones which are partners of the WHO or International Trachoma Initiative, and which are working in the developing world on cataract, trachoma or onchocerciasis (and not working on a range of other causes that seem less effective). There are some more, though the ones below likely include most of the major charities.

Fred Hollows Foundation

The Fred Hollows Foundation works in a very broad range of areas, including cataract surgeries, trachoma fighting, antibiotic provision, and eye screenings. Out of a total of A$41.5m on program expenses, the Fred Hollows Foundation likely spent between A$10 and A$20 million on the most effective interventions. The $/DALY figure of FHF is around 180-450 (taking cataract surgery at $90/DALY).

Helen Keller International

In 2013, Helen Keller International received $77,876,062 of in-kind medical supplies and medicine – very close to the figure for the distribution of in-kind medicines. As a result, it seems likely that additional donations will go towards the other programs. A significant proportion of other expenditure seems to be spent very effectively – a combination of effective interventions. The focus is on nutrition, which it is outside the scope of the report to consider, but seems promising. As such, HKI should be investigated further, though predominantly from the perspective of nutrition.

SightSavers

Unfortunately, SightSavers do not publicly provide data on the amount spent on areas within eye health. On their page on cataract, they put screening above provision of surgery, suggesting surgery is not their focus. In their financial reports, under surgery they specified the causes of blindness in brackets –“cataract, glaucoma, diabetic retinopathy, trichiasis in that order – suggesting that their focus is not exclusively on the most effective causes. We have emailed them to find out more but have not currently received a response.

From the above, the charity that seems most effective is Helen Keller International because of the high proportion spent on effective programs. However, to be sure of this, one will need to research their nutrition interventions in greater depth. SightSavers’ lack of transparency on the distribution of expenditure on eye care is surprising given the amount of other financial information they provide, but it seems likely that a significant proportion will not be spent on effective interventions. The Fred Hollows Foundation similarly seems to spend a significant proportion on less effective interventions.

While blindness is a promising area, donors should look elsewhere to have confidence in finding effective donation targets. It will be worth re-evaluating in a few years whether more can be done by charities to increase cataract surgery provision, and whether trachoma and onchocerciasis continue moving towards eradication.

Image taken from World Health Organization.