WHY IS ENCEPHALITIS SO DEADLY FOR CHILDREN?
What killed the children at Gorakhpur? While the jury is out on whether it was callousness, negligence or disease, there’s no getting away from the fact that those children would be alive if they did not have encephalitis.
Encephalitis is the swelling in the brain that leads to sudden high fever, headache, neck stiffness, disorientation, coma, seizures, spastic paralysis and, finally, death. If the symptoms are not treated within hours of the first few appearing, 30% of those affected die.
Those who pull through rarely do so without some degree of disability. About 30% suffer permanent intellectual, behavioural or neurological problems, including partial paralysis, recurrent seizures and the inability to speak.
Encephalitis symptoms can be caused by both Japanese Encephalitis (JE) and Acute Encephalitis Syndrome (AES), with cases for both peaking in the monsoon. Children under the age of 15 are the worst hit, with AES usually affecting severely malnourished children under 5.
This past week, 63 children with encephalitis died in Gorakhpur’s BRD Medical College. This district of Uttar Pradesh is the epicentre of annual outbreaks of both JE and AES, with several hundreds of young children from eastern Uttar Pradesh, northern Bihar and parts of Nepal being treated for encephalitis at BRD Medical College, which is the largest tertiarycare hospital in the region.
Here’s all you need to know about JE and AES.
JAPANESE ENCEPHALITIS
The JE virus is a flavivirus related to dengue, yellow fever and West Nile viruses. It spreads to humans from pigs and water birds through the bite of infected mosquitoes of the Culex family.
Feeding mosquitoes cannot pick it up from humans, however, which is why the disease is limited to rural and peri-urban areas where people live in closer proximity to pigs and water birds.
Globally, JE severely sickens about 68,000 people and kills between 13,600 and 20,400 people each year. In most people, it causes a mild fever and headache that disappear on their own within days. But it causes severe clinical disease in 1 in 250 people. One in three people die, after developing a sudden high fever, headache, neck stiffness and disorientation that progress to coma, seizures and spastic paralysis.
JE largely affects children under 15; most adults living in endemic countries develop a natural immunity from repeated childhood infections, but travellers to endemic areas risk infection at any age.
In India, infections occur all year but peak in the monsoon and in the pre-harvest period in rice-cultivating regions. Diagnosis is confirmed through laboratory testing of cerebrospinal fluid.
Since 2006, mass vaccination against JE has been carried out annually in 86 endemic districts in Assam, Andhra Pradesh, Bihar, Haryana, Goa, Karnataka, Kerala, Maharashtra, Tamil Nadu, Uttar Pradesh and West Bengal.
There is no cure. Treatment is supportive and aims at relieving severe clinical signs and supporting the patient as her body fights to overcome the infection.
ACUTE ENCEPHALITIS SYNDROME
Since India started vaccinating at-risk populations against JE, AES cases and deaths have outstripped it by five times. In 2016, AES infected 11,651 and killed 1,301, against 1,676 JE cases and 283 deaths. Till August 6, 2017, India had recorded 5,413 AES cases and 369 deaths; JE cases were at 838, with 86 deaths.
AES can be caused by a range of factors, including toxins in unripe lychee fruit, viruses, bacteria, fungi, parasites and chemical poisons. While it is also marked by inflammation of the brain that causes rapidly rising fever (crossing 104 degrees C within three or four hours), headache, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis, the condition is not vaccine-preventable.
In India, AES outbreaks in north and eastern India have been linked to children eating unripe litchi fruit on empty stomachs. Unripe lychees contain the toxins hypoglycin A and methylenecyclopropylglycine (MCPG), which cause vomiting if ingested in large quantities.
Hypoglycin A is a naturally occurring amino acid found in the unripened lychee that causes severe vomiting (Jamaican vomiting sickness), while MCPG is a poisonous compound found in lychee seeds that causes a sudden drop in blood sugar, vomiting, altered mental states leading to lethargy, unconsciousness, coma and death.
These toxins cause sudden high fever and seizures serious enough to require hospitalisation in young, severely malnourished children. Giving children sugar (glucose) to normalise their rapidly plummeting blood glucose levels helps them recover from the illness, recommended a study in journal, Lancet Global Health.