Nodding Syndrome(NS) is a neurological condition with a mystery. The name might sound innocuous but it is deadly. It is a form of pediatric epilepsy.
NS is a form of epilepsy which mainly attacks children between the age of 5-15 years. However, there are cases where reports have shown NS in kids less than 2 years and adults up to 32 years. NS causes progressive cognitive dysfunction, stunted growth, neurological deterioration and the characteristic “nodding off.”
Moreover, a child experiences seizure as they are being fed. The epileptic seizures weaken the head and the neck muscles. Thus their heads tend to fall forward. Although the mortality rate is not known, it is definitely big.
When Was the First Case of NS Reported?
NS was first documented in the United Republic of Tanzania in the 1960s. Later in the 1990s, other cases were reported in Southern Sudan and Northern Uganda. Until this date, only this areas have reported cases of NS. There is no definite number to showcase how many people have been affected.
However, there are feature seizures have a been reported in Liberia and Taiwan. It is believed that the parasitic disease extends much further than the three corners of East Africa. It extends in western Africa, Central and South America. Although there are no cases which have been reported in the later areas.
A lot of studies have tried to link NS with Onchocerca volvulus. Researchers believe that NS is an “autoimmune” disease which occurs when the infected persons try to fight off the worm.
Onchocerca volvulus is a tiny nematode which is spread by the bite of black flies. The black flies are known to cause river blindness which is an eye infection found in East Africa.
However, it has become a hard task for epidemiologists to prove that the worm indeed does cause NS. Researchers at the National Institutes of Health conducted researches among the people who live in this regions.
What did the Study Say?
The study found out that there were no traces of the worm in the brain nor in the cerebral spinal fluid (CSF). The team further looked at the antibodies.
It was discovered that there were high levels of antibodies which was tailored to leiomodin-1. Moreover, leiomodin-1 was also present in cerebrospinal fluid.
This was the first time researchers were discovering leiomodin-1 in the nervous system. This is because previous studies prove that it is commonly found in the muscles. It is commonly produced by nerve cells.
According to Tory Johnson, of America’s National Institutes of Health confirmed that leiomodin-1 antibody is toxic if it is isolated. This confirms the theory that NS is autoimmune meaning that the victims with NS attack their own brains.
These findings were further conducted. It was found that when healthy neurons are treated with serum from a person with NS, they did not survive. However, if they removed the antibodies against leiomodin-1, the neurons survived.
This begs the question why does the infection with O. volvulus should cause this antibody to be produced in the first place? Dr Johnson and her team have discovered that the worms produce a protein known as tropomyosin. Apparently, it has the same similar features as leiomodin-1.
However, it was not only tropomyosin which was found but a whole lot of similar proteins. The worm proteins are quite similar with human chemicals.
This explains why the antibodies which attack worm proteins lead to damage and harm in the human body. The antibodies bind with leiomodin-1 which incorrectly attacks the brain cells which contain protein. This, therefore, leads to an attack of NS.
These findings have further emphasized the efforts of getting rid of river blindness. Thus if it is eliminated then high chances are that NS will also be eliminated.
Moreover, the research raises the need to know if other parasites cause other forms epilepsy. For instance, Pinworms attacks millions of kids around the world. Thus it is possible that these infections cause this forms of epilepsy.
A Look at the Future
Studies are still being conducted to research to understand the unknown antibodies. The role of leiomodin-1 is still tantalizing especially in healthy individuals. Thus the question still begs can healthy individuals develop NS?
Whatever the details are current research has proved that NS may be caused by river blindness.