A mystery illness that has affected hundreds of children a year in northern India is caused by eating unripe lychee fruits on an empty stomach, scientists have discovered.
Since 1995, children in Muzaffarpur, Bihar have been seen to initially sustain a fever. They then have seizures and convulsions before slipping in and out of consciousness.
In Muzaffarpur, which is India's largest lychee cultivation region, the illness was branded locally as "chanki ki bimari" or "tinsel disease".
In a joint investigation conducted by scientists from May-July 2014 - which coincided with the lychee harvesting season - it was determined that 122 out of 390 children who suffered from the disease had died.
The investigation, which was reported in the British medical journal The Lancet Global Health on Tuesday (Jan 31), suggests that the deaths were caused by eating lychees on an empty stomach.
The researchers, who were from the US Centers for Disease Control and India’s National Centre for Disease Control, compared test results of children who had developed the mysterious illness, and children who had not.
Analysis of blood and spinal fluid samples showed no signs of infection or exposure to chemicals and insecticides.
However, most of the children who had fallen ill had eaten lychee fruit recently. They were also more likely to have visited a fruit orchard in the previous 24 hours, the study said.
The effect was compounded when the children skipped dinner, resulting in "night-time hypoglycaemia".
As these children already had low blood sugar levels, the impact of eating lychees that contain toxins that inhibits the body's ability to produce glucose would sometimes see the children suffer seizures and convulsions in the middle of the night as a result of acute swelling of the brain.
The toxins are found in higher quantities in unripe fruits, the report said.
The research findings has led to health officials in the region informing parents to ensure their young children ate dinner and reduce the number of lychees consumed.
According to a report by the New York Times, the number of reported cases per year has dropped to less than 50 from the hundreds affected in 2014.