Unpacking the Mystery of South-Sudan’s ‘Nodding Disease’

Nodding syndrome is a mysterious neurological disease of unknown aetiology characterised by head nodding and complicated by a variable presence of other seizure types that primarily affect children aged 5–15 years.

Dr Stephen Jada, a Research Scientific Coordinator at Amref Health Africa in South Sudan shares his experiences as a researcher for the Nodding Syndrome, Epilepsy and Onchocerciasis. In the interview below, he gives his perspective on the gaps, challenges and opportunities for research as well as notable successes in the fight against Neglected tropical diseases (NTDs).

Read the full interview:

Nodding Syndrome is one of the Neurological diseases mainly reported in Tanzania, Uganda and the Republic of South Sudan. In South Sudan, what causes the disease?

The direct cause of the Nodding Syndrome (NS) is not yet known, but the disease is still part of ongoing research. However, research that has been done until now has found a direct link between Nodding Syndrome and Onchocerciasis commonly known as “river blindness”. More research is needed to determine the linkage with the syndrome.

According to WHO, the Mundri region in the northeast of Western Equatorial is the presumed epicentre for the disease. Why is this the case?

Cases of the NS are reported in areas hyper-endemic for onchocerciasis and in villages close to rivers where the black flies that transmit Onchocerciasis are very active and with the rivers providing breeding sites. Hence, more cases of NS are rampant in the Western Equatorial region where they are hyperactive due to the rapid flowing rivers and streams.

What are some of the economic, social and psychological effects of Nodding Syndrome on the victims and communities?

The economic effects include high cost of treatment as a result of children requiring life-long medical attention with no subsidies. The families have to buy drugs for the children on a regular basis and some families could have two to four children with the condition in the same household. In addition, the families affected have to stay for several days at home instead of going to work, creating a further financial burden on the family.

The psychological effect is that with the disease progression, most children develop intellectual impairment such as mental retardation and hence are not able to undergo productive formal education to completion.

Socially, when families within a village have children with the condition, there is less productivity related to communal activities. The situation further complicates their already existing problems, such as poverty and neglect. People with epilepsy and Nodding Syndrome, including their families, experience stigma because the communities do not understand the cause of the diseases.

What are some of the outcomes of research conducted in Western Equatorial states (Mundri, Maridi and Mvolo) on Nodding Syndrome, Onchocerciasis as well as Epilepsy? What is the correlation between the three diseases?

We have done a study to determine the association between the increasing cases of NS in these counties and the correlation to Onchocerciasis.  We found out that most of the children who developed NS also have very high levels of Onchocerciasis parasite (microfilaria) in their bodies. The research outcome also revealed that when you control Onchocerciasis, you reduce the number of children developing NS. Nevertheless, how Onchocerciasis cause NS is an area of research that needs to be established.

What are some of the control or remedial strategies, activities and interventions Amref Health Africa in South-Sudan as well as other partners are doing to support the communities affected?

Amref Health Africa in South Sudan, in partnership with Ministry of Health, and the Nodding Syndrome Alliance (NSA), has been conducting mass treatments to control and eliminate Onchocerciasis, Epilepsy, and Nodding Syndrome, through the annual distribution of Ivermectin Treatment. The organisation also conducts bi-annual distribution to prevent more children from developing Onchocerciasis, Epilepsy, and the Nodding Syndrome. The bi-annual distributions started in 2021.

Amref established a Community vector Control  Intervention in 2019 to get rid of the black flies that transmit Onchocerciasis by removing their breeding sites. The removal of the breeding sites was done through slash and clearing of vegetation, which dramatically reduced the number of black flies. We are still doing surveys to determine the impact of the drastic reduction of flies on the transmission rate.

We also provide care for those who have been affected by the condition through the provision of anti-epilepsy and anti-seizure medicines. Clinics have been established in Mundri, Maridi, and Lui to provide treatment for the affected children. There are also follow-ups to monitor their progress through the Nodding Syndrome Alliance.

Lastly, the organisation addresses the problem of exclusion and stigma by creating awareness in those communities through community epilepsy awareness programmes, radios, and community meetings.

So far, there is no cure for nodding syndrome. What are the gaps, challenges and opportunities for research in this field of NTD?

Since there is an association between NS and Onchocerciasis, medicine is currently not recommended to children below five years. Hence, there is a gap in this area to finding the treatment option for children who are exposed to this condition and are below five years  No study has been done concerning the safety of the children below five years when it comes to consuming the medicines.

Studies could be done to determine the best ways of reintegrating the communities to become more productive. Studies are still ongoing to determine the reasons for the cases being experienced in certain countries such as South Sudan, Tanzania, and Uganda

Research published by the WHO in 2016 indicated that in Uganda, the NS epidemic appears to have abated and they linked the blackfly control interventions contribution to the decrease in NS cases in northern Uganda. However, it remains to unproven. Do you think applying the same method of intervention will reduce cases in South Sudan?

Uganda implemented the Vector Control Intervention and mass treatment of the population with ivermectin and successfully managed to interrupt the epidemics of the Nodding Syndrome in the affected areas. South Sudan has also implemented the intervention programmes and hopes no more children will develop the Nodding Syndrome after the implementation period. Amref Health Africa in South Sudan aims to conduct an evaluation this year to determine the effects of the interventions.

In your view, what are the important factors or best practices that need to be taken into account in order to sustainably reduce or eliminate the nodding syndrome in the affected regions?

There is still no cause for the Nodding Syndrome. However, there is a connection between the Onchocerciasis and the Nodding Syndrome. In this regard, we need to strengthen the Onchocerciasis Elimination Programme and increase the coverage to 80 per cent of the population to reach effective coverage that could eliminate the disease.

There is also the need to effectively train community members living near the areas where the black flies breed on the community vector control intervention ‘’slash and clear’’. The intervention is less costly, hence sustainable.

Another important factor to consider is the provision of consistent direct treatment to the children through the Nodding Syndrome Alliance. Amref is trying to tackle the problem of the Nodding Syndrome with the primary health care system by ensuring a consistent flow of medicine and treatment to clinics

Do you have any parting shot/final comments that you would like to make before we end the interview?

There are remarkable efforts we are doing to address the problem of Nodding Syndrome at various regions in the Western Equatorial. However, there is more to be done, especially in the area of elevating the stigma and social isolation that is being faced in the affected regions, because the provision of the pharmacological treatment is not going to do much.

People still believe that the conditions are caused by other things which are not medically related. For example, popular beliefs are that the condition is contagious or caused by evil spirits and that when the affected children go to school, they will spread it to other children. The teachers who are supposed to fight against the diseases do not know much about the condition. They, therefore, prevent children from accessing schools because of misconceptions. Addressing stigma is as essential as pharmacological treatment. Little work has been done on that, and hopefully, more efforts will be put future for more create awareness creation.

Dr Stephen JadaMD is a Physician and researcher working for Amref Health Africa in South- Sudan. He coordinates a research project aimed at evaluating the effect of community directed interventions in reducing the incidence of Onchocerciasis associated with Epilepsy and Nodding Syndrome, as well as improving the quality of life of people living with epilepsy and their families in Onchocerciasis endemic villages in South Sudan.