Nodding syndrome is a rare and poorly understood disease in which children become afflicted with characteristic head-bobbing seizures (hence the name), stunted growth and mental and physical disability. The condition was first identified in Tanzania in the 1960s, but the cause of this debilitating and distressing disease has remained a mystery. Researchers have long suspected that the parasitic worm Onchocerca volvulus(pictured), which also causes river blindness, might be involved because most nodding syndrome sufferers also have O. volvulus infections. New studies reveal that while the worm does not cause nodding syndrome directly, the body’s reaction to the parasite leads inadvertently to brain damage. Antibodies created by the immune system against proteins in the worm cross-react with host proteins in the brain causing cell death. The findings suggest that patients with this parasite-triggered disease may benefit from immunosuppressive therapies.
Written by Ruth Williams
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences (the new name for the MRC Clinical Sciences Centre) the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.