Mystery killer takes heavy annual toll of the young
Health experts are struggling to identify an encephalitis-style infection that has killed thousands of children in impoverished areas of northern India in the past two decades.
According to the New York Times, Indian doctors have joined forces with specialists from the US Centers for Disease Control and Prevention to track down the cause of the mystery illness that can strike down young children in a matter of hours, causing severe dehydration, convulsions and – in about a third of all cases – death.
The unidentified disease – first publicly noted in 1995 when an outbreak left 300 children dead and a further 700 seriously ill – appears every northern spring and summer, killing dozens, if not hundreds of children at a time, and striking fear into anxious parents.
This year, more than 70 deaths have been attributed to the disease in just one northern India state alone – Bihar – and authorities expect many more cases are going unreported.
The illness has been provisionally dubbed acute encephalitis syndrome, but tests for known causes of brain swelling such as meningitis and Japanese encephalitis have come back negative, according to the New York Times.
Senior Indian health officials admit they are in the dark about what the disease is, and how it is caused.
“This outbreak happens every year, and we have not been able to identify the cause, or link even a single factor responsible,” the Director of the National Centre for Disease Control in India, Dr L.S. Chauhan told the New York Times.
In an effort to lift the veil of mystery surrounding the disease, Dr Chauhan – with assistance from the US CDC – is training seven physicians to help try and track down the infection.
Working at the epicentre of the outbreak in the Muzaffarpur region, the team is investigating a wide range of potential causes and sources including viruses, bacteria, water contamination, pesticides, rats, bats, mosquitoes, sand flies and even alcoholic tree sap.
Australian virologist Dr Ian Mackay said in his blog Virology Down Under (http://www.uq.edu.au/vdu/) that it was hard to understand why it had taken so long for international collaborative efforts to identify the disease to get underway.
Dr Mackay said that, from available information, it was difficult to ascertain exactly what the Indian researchers were testing for, and what sort of facilities they had to conduct their tests.
“There are many infectious potential causes of such disease, and many, many potential sources for acquiring such pathogens, which includes a wide range of viruses,” he said. “Some of these viral culprits have only recently been discovered – the picornaviruses – klassevirus, parechovirus cosavirus and the Saffold viruses – among many better-known viruses.”
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