World Sight Day
Did you know that every minute, a child goes blind? Or that 80 percent of global blindness is preventable? This October 13 is World Sight Day, a day established to shed light on the impact of blindness and to raise awareness around the steps we can take to prevent it.
The Sabin Vaccine Institute has long worked to combat blindness through its efforts to control, treat and prevent vaccine-preventable and neglected tropical diseases (NTDs), two of which are trachoma and onchocerciasis (commonly known as river blindness). Together, these two diseases are the leading infectious causes of preventable blindness worldwide. Substantial progress has been made to eliminate trachoma and onchocerciasis, but over 200 million people are still at risk. What’s holding up progress?
When it comes to onchocerciasis, there is only one medicine that treats the infectious agent of the disease, a parasitic worm called Onchocerca volvulus that is spread by the black fly. The pharmaceutical company Merck & Co. has donated this safe and effective medicine, ivermectin, and has been recognized for its role in one of the most successful public-private partnerships in public health. While ivermectin can help reduce the prevalence of onchocerciasis, serious obstacles still remain in the effort to eliminate onchocerciasis.
Ivermectin only kills the larvae of O. volvulus, not the adult parasites. Consequently, communities require 10-20 years of annual treatment with ivermectin to ensure elimination. Furthermore, not all communities are eligible. Ivermectin can have contraindications for people who are infected with loiasis, another parasite, so it cannot be used with the 12 million people at co-risk for onchocerciasis and loiasis. To exacerbate the issue, symptoms of resistance to ivermectin are beginning to appear in some regions.
Some experts now predict that ivermectin alone will not be able to eradicate onchocerciasis. Other experts predict it may take another half century. That’s a long time for public health workers to stay in regular contact with secluded communities; it’s a long time for drug companies to have to donate billions of treatments; and it’s too long for communities to have to deal with such a disabling disease, even at a controlled level.
Here at Sabin, we’ve partnered with The Onchocerciasis Vaccine for Africa (TOVA) Initiative to develop an onchocerciasis vaccine. If successful, such a vaccine could break transmission more quickly, meaning that the elimination of onchocerciasis could be brought within sight.
Trachoma, the other leading cause of preventable blindness, is a bacteria often spread between mothers and children. Its elimination also faces hurdles, but progress is accelerating. A 2016 report by the WHO Alliance for the Global Elimination of Trachoma by 2020 stated that approximately $1 billion is needed in order to eliminate trachoma. While daunting, it is important to consider that $8 billion is lost in economic productivity due to the debilitating side effects of trachoma. Stakeholders have already committed $300 million, and just within the last five years the number of individuals at risk has dropped by a third. These are encouraging signs that the elimination of trachoma is achievable.
If either of these NTDs could be eliminated, the risk of blindness would be lifted for millions of people. Losing the ability to see is a devastating and life-changing event. This year, as we recognize World Sight Day on October 13, join us in renewing our fight to reduce the needless human suffering from trachoma and river blindness.