AN illness which has left 231 people paralysed in just a few months has baffled doctors - and the cause remains a mystery.
Officials have declared a national health emergency in Peru after a wave of Guillain-Barré Syndrome (GBS) infected 231 people and killed four since January.
The rare condition sees the immune system attacking healthy nerve cells and it usually follows a viral or bacterial infection.
Most patients experience symptoms that start in feet and hands, before spreading to arms and legs.
People suffer from numbness, pins and needles, muscle weakness, pain and problems with balance and coordination.
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Scientists are battling to find the root cause of the sickness.
Samples analysed by health officials in Peru suggest it could have come from the bacteria Campylobacter jejuni, commonly found in contaminated food and water.
The same bacteria was responsible for a similar GBS outbreak in Peru a few years ago.
While GBS can leave patients with long-term problems it is rarely fatal and most make a full recovery.
The Peruvian government, the World Health Organization or the Pan American Health Organization have not issued any travel restrictions over the GBS outbreak.
The World Health Organisation has said: "Guillain-Barré syndrome is potentially life-threatening.
"GBS patients should be hospitalised so that they can be monitored closely.
"Supportive care includes monitoring of breathing, heartbeat and blood pressure.
"In cases where a person’s ability to breathe is impaired, he or she is usually put on a ventilator.
"All GBS patients should be monitored for complications, which can include abnormal heartbeat, infections, blood clots, and high or low blood pressure.
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"There is no known cure for GBS, but treatments can help improve symptoms of GBS and shorten its duration.
"Given the autoimmune nature of the disease, its acute phase is typically treated with immunotherapy, such as plasma exchange to remove antibodies from the blood or intravenous immunoglobulin.
"It is most often beneficial when initiated 7 to 14 days after symptoms appear.
"In cases where muscle weakness persists after the acute phase of the illness, patients may require rehabilitation services to strengthen their muscles and restore movement."
The highest number of cases was recorded in capital Lima two weeks ago, with the average patient being around 41 years old.
Experts advise those travelling to areas with GBS to focus on hand hygiene and food choices.
Peru's outbreak comes as the country is also battling a massive outbreak of Dengue fever which has affected at least 150,000 people.
