hal compared to the non-viral. What is known about them?
JEV is an arbovirus, transmitted to humans by insects—typ-
ically, the culex mosquito. The Chandipura Virus (CHPV) is
a rhabdovirus, a poorly characterised new virus that is, that
mutates incessantly—making it particularly lethal. CHPV is
transmitted by sand flies and culex mosquitoes. Bats are
reservoir of many highly infectious AES pathogens: Nipah
virus and West Nile virus to Kyasanur forest disease virus.
Herpes Simplex Virus, the most common cause of AES
among children in Eastern India, spreads person-to-person.
Enteroviruses, increasingly recognised as an important
pathogen for AES, spread via water, food and soil. Rotavirus,
the prime culprit behind the daily deaths from diarrhoea
among children, can also cause hypoglycaemia (extremely
low sugar in blood) and convulsions. And, despite the 1.2 lakh
diarrhoeal deaths among children every year, Bihar is still to
introduce the free rotavirus vaccine.
Tinkering with nature
The biggest challenge lies elsewhere. As the viral theory gains
ground, AES becomes a spectrum of zoonotic diseases, where
the pathogen jumps species and is transferred from animals
to humans. In the 21st century, zoonotic diseases have caught
the world unprepared: from the Severe Acute Respiratory
8 July 2019 OutlOOk 35
Graphics by Saji C.S.
THE SPREADING TENTACLES
How Acute Encephalitis Syndrome has spread through the country
Siliguri
Nipah virus,
2001
Warangal
Chandipura virus, 2003
2003
Odisha (Bhubaneswar,
Dhenkanal, Khurda,
Malkangiri, Keonjhar,
Balasore, Kendrapara,
Jharsuguda and Debgarh)
Scrub typhus virus, 2014-17
Muzaffarppur
Enterovirus, 2017
Gaya
Chandipura virus, 2017
Champaran
1978
Lucknow
2005
Assam
2000
Dimapur
1985
Manipur
1982, 1995
Bankura*
1973
Cuttack
1989
Raipur
1980
Anantapur
1999
Kolar
1978
Tamil Nadu
1978, 1981, 1999
Goa
1982
Sangi
1997
Vadodara
2004
Haryana
1990
Chandigarh
Measles virus, 1997
1997
Sikkim
Scrub typhus, 2003–04
Darjeeling
Scrub typhus, 2007
Aizawl
Scrub typhus
virus 2017-18
Gorakhpur
Enterovirus,
scrub typhus,
2006-18
JEV,
1978-2005
Kozhikode
West Nile virus, 2018
Kochi Nipah virus, 2018
Shimoga
Kyasanur forest
disease, 2018
Nagpur
Chandipura virus,
2012-14
Eastern Gujarat
Chandipura virus
2004, 2009-12
Jodhupur and Jaipur
Herpes simplex virus, 2018
Himachal Pradesh**
Scrub typhus, 2003–2004
Old AES: Outbreak
attributed to Japanese
encephalitis virus (JEV)
New AES: Outbreak
attributed to other
* Bankura, Bardhaman: First JEV outbreak identified in 1973 pathogens
* * First non-JEV outbreak (measles) identified in Himachal Pradesh, 1997
Udaipur
West Nile virus, 1997
map not to scale