Elimination of “river epilepsy” has started in South Sudan

Robert Colebunders, Global Health Institute, University of Antwerp. March 2020.

In November 2013, I visited Mvolo, in South Sudan, in an effort to identify the cause of nodding syndrome, at that time a mysterious form of epilepsy of unknown aetiology. The situation in Mvolo was catastrophic. A rapid assessment showed that one in six children had epilepsy and one in two families had at least one child with epilepsy. I felt very uncomfortable because I had nothing to offer them to reduce the suffering in this village: no advice to give on how to protect children from developing develop epilepsy and no treatment to provide. However I promised the local community that I would do my best to come back with a solution.

We are now nearly seven years later. In the mean time we have been able to carry out a lot of research on epilepsy in many onchocerciasis (river blindness) endemic regions in Africa. Onchocerciasis is a tropical disease caused by a worm and transmitted by blackflies, well known to cause skin and eye disease but was until recently not considered to result in epilepsy.

Here is what we, in collaboration with many others including AMREF have discovered so far:

• Nodding syndrome is only one of the types of epilepsy induced by onchocerciasis.
• This form of epilepsy is a major public health problem in onchocerciasis-endemic regions where onchocerciasis was or still is poorly controlled such as in parts of South Sudan, Cameroon, the Democratic Republic of Congo, Uganda, Tanzania and the Central African Republic.
• This form of epilepsy is observed in villages close to rapidly flowing rivers where blackflies put their eggs.
• Therefore in analogy with river blindness this form of epilepsy could be called river epilepsy.
• River epilepsy can be prevented by strengthening onchocerciasis elimination efforts: by increasing the coverage of mass distribution of ivermectin (the drug that kills the worms), and by distributing this drug twice a year instead of once.
• The mechanism of how the worm causes the epilepsy) still needs to be discovered; but we showed in Uganda that if onchocerciasis is eliminated, river epilepsy disappears.

It has been a great struggle to convince the scientific world that onchocerciasis is able to induce epilepsy, and that this major public health problem urgently needs to be addressed. It was even more difficult to convince funders to finance interventions to stop this form of epilepsy.

Only recently we obtained funding from the Italian Agency for Development Cooperation, through Amref Health Africa and from R2HC-Elrha (Welcome Trust, NIHR and DFID funding) to establish and evaluate a community-based comprehensive epilepsy prevention and treatment programme in onchocerciasis endemic villages in South Sudan. This programme has now started in Maridi and Mundri and will later also be implemented in Mvolo.

Thanks to an onchocerciasis and epilepsy awareness campaign the coverage of ivermectin increased from 40.8 to 79.4%. Moreover a community based vector control using the “Slash and clear method” has started.

Villagers are removing all vegetation at the level of the Kazana dam in Maridi, a blackfly breeding site. This is expected to eliminate the blackfly breeding sites possibility and therefore will limit the spread of onchocerciasis and stop river epilepsy in Maridi.

In addition anti-epileptic drugs have been ordered, and training of health care workers to diagnose and treat epilepsy will start soon In Maridi and Mundri. Funding for scaling-up the programme is urgently needed.