For years, a mysterious disease has been plaguing India, claiming the lives of young children in the town of Muzaffarpur in Bihar. Now, researchers finally know what's causing the disease, confirming that the lychee, or litchi, fruit may have been behind all those deaths.
It all began in 1995. Around May or June of each year, numerous young children would begin exhibiting symptoms of fever, eventually having seizures and convulsions prior to slipping in and out of consciousness. Locally, the disease is referred to as "tinsel disease," or "chamki ki bimari." Of the 390 children admitted to hospitals after showing symptoms of the disease from May 26 to July 17 in 2014, 122 died.
Studying A Mystery Illness
In a study published in the journal The Lancet Global Health, researchers detailed lychee's role in the disease, which leads to brain inflammation, a symptom resembling that of encephalitis. A team of scientists from India's National Center for Disease Control and the U.S. Centers for Disease Control and Prevention compared results between children who got sick and those who didn't.
Based on their findings, the problem was not caused by exposure to insecticides or chemicals. Additionally, they also observed that majority of the sick children had eaten lychees recently and were also six times likelier to have gone to a fruit orchard within the last 24 hours.
With lychees identified as a factor, it made sense why Bihar, in particular Muzaffarpur, had been hit by the disease: the region is India's largest litchi producer.
According to accounts from parents, affected children had spent most of their day eating the fruit from surrounding orchards before getting sick. When they returned home, they said they didn't want to eat, skipping dinner.
Unfortunately, this resulted in night-time hypoglycemia. With low blood sugar levels, the body moves to metabolizing fatty acids to achieve a glucose boost. However, a chemical called Methylene cyclopropyl-glycine found in lychee seeds, which appears in higher levels when the fruit is not ripe, prevented glucose synthesis and caused dangerously low levels of blood sugar as well as inflammation in the brain of the sick children.
Dealing With Tinsel Disease
Residents in affected areas are being advised to look after children to ensure minimized consumption of the lychee fruit. Additionally, children are to eat evening meals during the outbreak period to prevent drops in blood sugar levels associated with the mystery illness.
But while they were able to confirm lychee consumption as a factor, the researchers still have questions about the mystery illness. For instance, usually just one child in every village in the town gets sick even when the area is surrounded by orchards. This points to another factor that may have a genetic component, they said.
Similar outbreaks of tinsel disease were reported in other lychee-producing areas in India, like in West Bengal, as well as other countries like Bangladesh and Vietnam. Other factors may be at play in outbreaks in other countries but the researchers underscore the importance of using systematic methods in assessing widespread illness.
"A comprehensive investigative approach in Muzaffarpur led to timely public health recommendations," they added.