A mysterious epidemic in Africa can be caused by worms-parasites

Frequent cases of strange epilepsy that turns children into invalids attracted the attention of physicians around the world. No one was able to figure out the exact cause of the disease, but scientists believe that the fault lies on dangerous parasites.

In the period from 1990 to 2013, in war-torn southern Sudan and Northern Uganda in thousands of children suddenly developed a severe and complex form of epilepsy. Under the influence of low temperatures and during the meal, susceptible to the disease children began uncontrollably shaking the head. Over time, the seizures worsen, leaving children with disabilities. Many eventually died from malnutrition, accidents, or secondary infection.

In some communities, about 50% of families had at least one child with the "nodding syndrome", so by 2013 about 1,600 children suffered from this syndrome. The reason for this strange epidemic remained a mystery for physicians. A new study showed that the parasitic worm frequently found in children, can cause the body's defense systems to attack its own neurons.

The study doesn't prove directly that it is all the fault of the he worm, but in the first place demonstrates that "such a connection is quite likely," as Herman Feldmeier says, parasitologist of the Clinical Centr Ccharité in Berlin, who was not involved in the work.

A new outbreak of the disease in Uganda and southern Sudan has led to an intense activity of the specialists, but at the end they just shrug shoulders: viruses, bacteria, environmental toxins, genetics and even shortage of food, all this, apparently, neither here nor there. One of the key clues turned out to be another disease: areas where manifested "nodding syndrome", were characterized by a high incidence of Onchocerca volvulus — a disease which is caused by parasitic worms onchocercosis They move from one carrier to another by the bites of black flies, and by blood flow often fall into the eyes, causing infection commonly known as " river blindness". According to WHO estimates, about 18 million people are infected today in African countries

In the 60-ies the researchers suggested that outbreaks of epilepsy in Tanzania are also linked to Onchocerca volvulus. However, there was no evidence that the worm enters the brain and cramps. The scientists put forward the hypothesis that the parasite just causes an autoimmune response, which damages the nervous system. Initially search of antibodies gave no result, however, the neuroimmunologists Avindra Nathan and Tori Johnson from the National Institute of Health in Maryland decided to repeat the test, using an improved protein chip, which allows the screening of antibodies against thousands of proteins simultaneously.

The device proved its suitability. The patients’ blood reacted to 4 of protein, but to one of them, laomedon-1, the reaction was 33000 (!) times stronger than that of healthy people. According to the scientist’s article published in Science Translational Medicine, antibodies to the protein were detected in 29 of the 55 patients. Johnson’s team even found a key to what may cause an autoimmune reaction to the protein: some proteins it is all about Onchocerca volvulus.

If the hypothesis of scientists is correct, then the disease would be finished in no time. Unfortunately, those who have already suffered from it, there is almost no help: their body is too badly damaged from the infection. Researchers still wonder, why every here or there happen outbreaks of "nodding syndrome" if Onchocerca volvulus in this region is a frequent phenomenon and does not have the character of mass epidemics.