UNICEF India lauded Uttar Pradesh for a campaign against encephalitis. A researcher says the government has taken steps to control the disease ahead of the monsoon.

In what was seen as a significant achievement for the Uttar Pradesh government, UNICEF's India chapter on 25 April congratulated the state "for immunising every child" against Japanese Encephalitis (JE) and Acute Encephalitis Syndrome (AES). This comes just months after reports of over 1,300 deaths in the state-run BRD Medical College in Gorakhpur alone in 2017, with most deaths linked to encephalitis.

The Uttar Pradesh government's Dastak campaign was launched by Chief Minister Yogi Adityanath on 2 April, where government officials went door-to-door in 38 districts affected by the disease to spread awareness and ensure timely vaccination. The programme ended on 16 April. Senior BJP leaders such as Sunil Deodhar took to Twitter to congratulate the state government "for successfully immunising all children" against the diseases.

Weeks before UNICEF's recognition, a report published in the Journal of Medical Entomology, titled "Acute Encephalitis Syndrome in eastern Uttar Pradesh, India: Changing Etiological Understanding", conducted a detailed review of academic studies done on the seasonal outbreaks of AES in Gorakhpur over three decades, and possible causes behind them. Among several other things, the report talked in detail about the efficiency of vaccination drives undertaken in the state in recent years.

Manoj Murhekar, corresponding author of the report and scientist at National Institute of Epidemiology under the Indian Council of Medical Research (ICMR), said the paper is "a compilation of etiologies until now", and what academic papers have found in Gorakhpur to explain the current health situation. "ICMR has already issued necessary guidelines and instructions to the government to form policy. The point of this report was to help form future studies based on what we know so far," he said.

Vaccination and the slow decline in cases of JE

The report — compiled by Murhekar, Jeromie Wesley Vivian Thangaraj, Mahima Mittal, and Nivedita Gupta from various institutes across India — says that it was after the 2005 outbreak that the government introduced vaccines against JE in Gorakhpur, as part of a mass vaccination campaign targeting children between ages 1 and 15 years. Even though the reported coverage of this initial campaign was well above 95 percent, the report says that the evaluated or "true" coverage was only 52 percent.

In order to ensure higher protective efficacy of the vaccine, the single-dose strategy was replaced by a two-dose strategy in 2013. The coverage of the Japanese Encephalitis Virus (JEV) vaccine soon increased in the region, with a survey in 2015 revealing that 75 percent of children had received at least one of the two doses. The coverage of the second dose was still low, the report revealed, with only 42.3 percent children receiving both doses.

The report blamed a "misconception among health workers about simultaneous administration of vaccines" as the main reason for the low numbers. The incidence of JE, it said, declined over the years, from 1.9 per 1,00,000 in 2010 to 0.5 per 1,00,000 in 2012. The incidence of JEV-negative cases, however, remained relatively stable over the years.

About the current Dastak campaign, Murhekar says it is not surprising that vaccination drives have now reached every child. "Our surveys in 2015 showed that three in four children received at least one dose of vaccination against JE. Now if UNICEF says every child has been immunised, it is quite possible that it is the case; it is the result of several special campaigns to increase the coverage of the vaccination drives," he said.

When vaccination was introduced in Gorakhpur after the 2005 outbreak, Murhekar explained that "around 50 percent of the cases were due to JEV". In contrast, less than 7 or 8 percent of the cases are attributed to JEV now. "This decrease could have only been realised through vaccination. Although the government says it is doing many things to control AES, it is primarily because of vaccination that JEV cases have come down. In non-JEV etiology, nothing really has been done, so the cases remain stable," he said.

UP's history of AES

AES is an umbrella term for all symptoms which lead to inflammatory brain diseases — the syndrome can be caused by bacteria, fungi or virus of different strains which are difficult to identify individually. The World Health Organisation (WHO) defined AES as follows: An acute onset of fever and change in mental status (including symptoms such as confusion, disorientation, coma, or inability to talk) and/or new onset of seizures among a person of any age, at any time of year.

A total of 12,578 people were affected by AES across the country in 2017, a rise of over 243 percent since 2010, data procured through RTI from the National Vector Borne Disease Control Programme (NVBDCP) showed. The RTI response also said that a total of 74,535 cases of AES have been recorded in India since 2010. As another Firstpost report pointed out last year, over 26,000 of these cases were observed in Uttar Pradesh alone.

NVBDCP, which is an agency under the Ministry of Health and Family Welfare, added in its reply that this year too, Uttar Pradesh carried the largest AES burden in India at 4,515 cases, followed by Assam and West Bengal.

Cases of encephalitis are reported mostly in the monsoon season — they start around July and continue to be reported in high numbers till end of October. So, with the monsoon fast approaching, is the government taking measures to reduce the number of cases this year? Murhekar replies in the affirmative.

"This year, fever-management will be critical — to detect cases at an early stage and treat the fever accordingly. The WHO will also get involved in the fever-management efforts of the government. The government's communication strategy has also changed — this year, UNICEF is preparing communication material to spread awareness among the public. We should see positive results," he said.

The Japanese Encephalitis Virus

For a long time, JEV was considered to be the "leading and consistent cause" of AES outbreaks in Gorakhpur between 1978 and 2010. A declining trend observed in the decade between 1988 and 1997 was followed by a sharp increase in JE cases between 1997 and 2007, the paper quoted above said. Later, between 2008 and 2012, only 8.4 percent of all AES cases registered were due to JEV, with a case-fatality ratio of 20 percent.

JE is caused by rice field breeding mosquitoes (primarily the Culex tritaeniorhynchus group) that become infected with the virus. The mosquitoes, in turn, are infected by the virus by feeding on domestic pigs and wild birds which are infected.

Pigs are one of the most commonly domesticated animals in rural areas of Gorakhpur, the paper said. The presence of a large number of pigs coupled with abundant mosquito populations contribute to play a vital role in peridomestic JEV transmission. Eastern UP's topography may also be a factor causing the spread of this disease. A BBC report pointed out that this region, which is at the foothills of the Himalayas, is prone to flooding, which helps make it a breeding ground for mosquitoes.

While investigations conducted during the 2014 and 2015 outbreaks indicated that Orientia tsutsugamushi is the leading case of AES, accounting for over 60 percent of all cases, JEV accounted for only about 10 percent of AES cases. "Dengue accounts for about 5 percent of AES cases. The etiology of the remaining cases is still unknown," Murhekar said.