What you need to know about nodding syndrome

It is being bitten only by blackflies infected by the worm that causes River blindness that you may develop nodding syndrome and other forms of epilepsy. You develop this disease between the age of 5 and 15 years because you need to have been exposed for several years and be very heavily infected with the worm before you develop the disease. To develop blindness, it takes many more years of exposure. Therefore, epilepsy appears at a young age and blindness at older ages.

Epilepsy caused by River blindness existed also before the war in the Kitgum and Pader districts but the numbers were low. During the war, an epidemic of infection with the worm that causes River blindness appeared because there was increased contact with the rivers. This epidemic of worm infection was followed by an epidemic of epilepsy.

I was misquoted about the grazing cows. It is indeed not contact with grazing that may favour the developing nodding syndrome. It is probably the reverse. It is possible that the disappearance of the cows from the sub-region during the war may have played a role in causing the epidemic. Indeed being bitten by blackflies that also bite cows may provide a degree of resistance against River blindness. Therefore in the absence of the cows, children, particularly malnourished children, may be more susceptible to develop the disease. One of the main arguments that the worm that causes River blindness causes nodding syndrome and other forms of epilepsy is that the drug ivermectin (Mectizan) that kills the worms, protects against developing epilepsy and can stop a nodding syndrome epidemic.
Robert Colebunders,
bcoleb@itg.be