Kolkata: Blood samples of victims of a purported viral infection in West Bengal`s Malda district that left seven children dead in a week are being sent for tests to ascertain if these are linked to deaths in Bihar, official sources said Wednesday.
The sources said the samples are being sent to Pune`s National Institute of Virologyto determine the causative organism whose "exact identity" has eluded researchers so far and is being associated with the consumption of the litchi exotic fruit.
The children, aged between two and four years, died due to swelling of brain (encephalitis), according to doctors at the Malda Medical College and Hospital (MMCH) in West Bengal.
They exhibited a sudden onset of fever, convulsions and succumbed within five to six hours of the appearance of the symptoms.
In Bihar, 44 deaths due to acute encephalitis syndrome (AES) have been reported from six districts over the past fortnight.
A team of experts from Calcutta School of Tropical Medicine (CSTM) here visited the area in Bengal recently to collect samples.
Dubbed as the "Litchi syndrome" by the local health workers, the "unknown strain" is thought to spread from litchi fruits, though there is no concrete proof yet, according to a member of the inspecting team.
So far, the collected samples have tested negative for Japanese encephalitis (JE), chikungunya and dengue virus. Additional tests for other strains will be done at Pune.
"We think it is a virus because it spreads in a small area. However, we can say for sure after the final tests. Once we get the results in the next seven to 10 days from Pune, we can determine if at all it spread from litchi," Rahman, assistant professor at CSTM`s Tropical Medicine unit, told IANS.
"Most importantly, the attempt will be to identify any links with the Bihar children deaths," he said.
Meanwhile, residents in Malda have been advised to refrain from consuming the juicy fruit and have been cautioned to wash fruits thoroughly before eating them, according to M. A. Rashid, the hospital`s vice principal cum superintending officer.
What is more intriguing is that the victims were hypoglycemic, that is, they had an abnormally low blood glucose content.
This condition in under-nourished children could have been triggered by a toxic substance called methylenecyclopropyl-glycine (MCPG) found in litchi fruits, according to the experts.
A hypothesis "Acute encephalitis syndrome in children in Muzaffarpur: hypothesis of toxic origin" published in May in Current Science journal states the Muzaffarpur AES is caused by MCPG in litchi.
"We have advised parents to keep the children well-fed as they were eating after long intervals and the chemical linked to litchi may have triggered some reaction," he said, adding the incidences need to be taken seriously.
Concerned about the large number of suspected encephalitis deaths in the country, Health Minister Harsh Vardhan Tuesday asked officials to target 100 percent immunization of children.
The health minister said the drive to eradicate encephalitis should replicate the Pulse Polio campaign.