The National Institutes of Health (NIH) has awarded a grant to a Baylor College of Medicine-led study team working to research and develop a vaccine for onchocerciasis, or river blindness.
Transmitted by the parasitic worm Onchocerca volvulus
through bites from blackflies, river blindness
is the world’s second leading infectious cause of blindness. The disease is endemic to 31 countries in sub-Saharan Africa
and has also been transmitted in Yemen as well as in parts of Latin America. The blackfly that carries the parasite breeds in the fast-flowing waters of rivers and streams, and once a female adult worm enters a human body, it produces larval worms that travel to the skin and eyes. According to the Centers for Disease Control and Prevention
(CDC), an adult O. volvulus
worm can live inside a human for up to 15 years, and female worms can produce thousands of larvae each day. While some infected individuals do not experience symptoms, those who do may develop itchy skin rashes, nodules under the skin, vision changes, and eventually blindness.
River blindness is typically treated with the anti-parasite medication ivermectin
, and the World Health Organization
(WHO) notes that in the absence of a vaccine to prevent these infections, the disease has been largely mitigated or eliminated through insecticide spraying and other methods. From 1974 to 2002, the Onchocerciasis Control Programme in West Africa used insect spraying and ivermectin distribution to relieve 40 million cases of river blindness, prevent blindness in 600,000 individuals, and protect 18 million children from being born into the threat of the disease.
In a sign that a vaccine may soon be in the pipeline, Baylor College of Medicine recently announced
that researchers at the college’s National School of Tropical Medicine are part of a team that has received a 5-year, $3.6 million grant from the NIH’s National Institute of Allergies and Infectious diseases (NIAID) to research and develop an onchocerciasis vaccine. The team also includes researchers from the Texas Children’s Hospital’s Center for Vaccine Development, New York Blood Center, University of Liverpool, and Thomas Jefferson University.