Welcome to the South African Society of Travel Medicine (SASTM) website.

The SASTM’s Mission is to guide the profession in all aspects relating to the practice of travel medicine, liaise with the travel industry, consult with relevant authorities, advise the public and collaborate nationally and internationally on all aspects relating to Travel Medicine. Click here to learn more.

SASTM Newsflash - Japanese encephalitis and other - India


Group Email






Poor surveillance, incomplete diagnosis and unsubstantiated scientific claims have stymied India's efforts to control the mystery encephalitis that has killed 3000 children in eastern India over the past 3 years, health researchers have said.


A new study has warned that low-quality surveillance appears to be obstructing attempts to understand the cause of the acute encephalitis syndrome (AES) observed mainly in Assam, Bengal, Bihar and Uttar Pradesh with sporadic cases in other states.


The Union health ministry documented more than 21 600 patients with AES, including 3171 deaths, most of them in the eastern states, between 2010 and 2012. A central government programme that tracks encephalitis, or brain inflammation, has claimed that waterborne enteroviruses have replaced the Japanese encephalitis virus as the main cause of encephalitis. But many scientists believe the identity of the viruses still remains hazy.


"In this time and age, there can be no excuse for failing to identify an unknown virus," said a senior government scientist who requested not to be named. "Technology exists today to sequence a virus in less than 6 hours," the scientist told The Telegraph.


The study on the quality of surveillance and diagnosis examined the case records of patients from Kushinagar district in Uttar Pradesh and suggested that assertions that waterborne enteroviruses are the dominant cause of encephalitis are not backed by adequate scientific evidence.


"Without reliable scientific evidence, it is very easy to shift the hypothesis (of the cause of the encephalitis)," said Manish Kakkar, a microbiologist and faculty member at the Public Health Foundation of India, New Delhi, a research and training institution.


Kushinagar has been among hubs of encephalitis in eastern India where the Japanese encephalitis virus picked up through mosquito bites had been considered the primary cause of encephalitis from the 1970s until about 2010.


The Union health ministry had introduced a mass vaccination campaign against the Japanese encephalitis virus in the affected states in eastern India in 2006 with a fresh campaign in 2010, but both Japanese encephalitis and AES have persisted.


Health ministry figures suggest that AES has outnumbered Japanese encephalitis (JE) [cases] over the past 3 years. During 2012, for instance, India had 745 cases of JE and 8344 cases of AES, with 140 deaths from JE and 1256 deaths from AES.


Kakkar and his colleagues have found that the results of diagnostic tests on samples or blood or cerebrospinal fluid from 590 (82 per cent) out of 721 encephalitis patients registered at a district hospital during 2011 were still awaited in July 2012, after virtually all the children had been discharged or died. In 80 per cent of the cases, health authorities had no idea whether patients had been vaccinated.


"These findings are shocking; with such gaps in information, it's hard to estimate the effect of the vaccination or to determine what might be causing the illness," said Kakkar, lead author of the study published in the journal Emerging Infectious Diseases [see below].


The National Institute of Virology (NIV), Pune, under the Indian Council of Medical Research has set up a surveillance centre in eastern Uttar Pradesh to help analyse samples from patients and try to identify the cause of the AES.


The NIV has said it has detected in samples of cerebrospinal fluid of patients with encephalitis genetic material resembling that of enterovirus 89 and enterovirus 76, and throat swabs of patients have turned up signatures of the coxsackievirus and 2 types of echovirus. "Enteroviruses are known to cause encephalitis, and our evidence is strong," a senior NIV scientist said.


But Kakkar and his colleagues say the focus of health authorities has shifted to enteroviruses even though the studies that found enteroviruses in patient samples have not demonstrated that waterborne pathogens are the main cause of the encephalitis.


"What Kushinagar shows is India's failure to establish a reliable public health surveillance network," said T. Jacob John, a senior virologist formerly with the Christian Medical College, Vellore.


"We don't need to pinpoint the cause to treat children with encephalitis, for the medical management of the illness," John said. "But to prevent new infections, we have to understand what's causing them."




In India, quality surveillance for acute encephalitis syndrome (AES), including laboratory testing, is necessary for understanding the epidemiology and etiology of AES, planning interventions, and developing policy. We reviewed AES surveillance data for January 2011-June 2012 from Kushinagar District, Uttar Pradesh, India. Data were cleaned, incidence was determined, and demographic characteristics of cases and data quality were analyzed. A total of 812 AES case records were identified, of which 23 per cent had illogical entries. AES incidence was highest among boys under 6 years of age, and cases peaked during monsoon season. Records for laboratory results (available for Japanese encephalitis but not AES) and vaccination history were largely incomplete, so inferences about the epidemiology and etiology of AES could not be made. The low-quality AES/Japanese encephalitis surveillance data in this area provide little evidence to support development of prevention and control measures, estimate the effect of interventions, and avoid the waste of public health resources.



The current AES/JE surveillance system has a complicated specimen referral and reporting system at the district level, and the available line lists suggest that data are of low quality. Without evidence to estimate the effect of interventions, AES prevention and control measures may be ineffective, and public health resources may be wasted. In 2011, AES and JE were highlighted in the national media, leading to a declaration for several policy initiatives, including formation of a multi-sectorial and inter-ministerial National Encephalitis Control Programme. Despite the high profile of AES, the importance of surveillance data for guiding these initiatives has not been realized or translated to action. Gaps in surveillance capacity that were identified in this study indicate the need for a systematic evaluation of the AES/JE surveillance system in Kushinagar District and constitute key lessons that need to be incorporated as strategic planning is undertaken for this new initiative.


Communicated by: ProMED-mail




South African Society of Travel Medicine (SASTM)

Phone: +27 (011) 025 3297
Fax: +27 087 9411350 / 1
E-mail: admin@sastm.org.za
Website: www.sastm.org.za
Postal address: SASTM, PO Box 8216, Greenstone, 1616, South Africa
Physical address: SASTM, 27 Linksfield Road Block 2 a Dunvegan Edenvale
Registered as a Nonprofit Organisation 063-296-NPO


The content and opinions are neither pre-screened nor endorsed by the SASTM. The content should neither be interpreted nor quoted as inherently accurate or authoritative.

The information provided in SASTM Newsflashes is collected from various news sources, health agencies and government agencies. Although the information is believed to be accurate, any express or implied warranty as to its suitability for any purpose is categorically disclaimed. In particular, this information should not be construed to serve as medical advice for any individual. The health information provided is general in nature, and may not be appropriate for all persons. Medical advice may vary because of individual differences in such factors as health risks, current medical conditions and treatment, allergies, pregnancy and breast feeding, etc. In addition, global health risks are constantly evolving and changing. International travelers should consult a qualified physician for medical advice prior to departure.

Scroll to Top