Encephalitis is in the spotlight again, thanks to the high number of child deaths in Bihar. But what does data say about the prevalence and control of Encephalitis?
The discussion about Encephalitis, child deaths, malnutrition etc. has again come to the forefront with the deaths of more than 100 children in Bihar as per official figures, with a high number of child deaths being recorded in the district of Muzaffarpur. Many of these deaths are attributed to Acute Encephalitis Syndrome (AES).
Many of the deaths in India are attributed to Japanese Encephalitis Virus (JEV)
One of the earliest cases of Acute Encephalitis (AEC) in India is the Japanese Encephalitis Virus (JEV), recorded in 1955 from Vellore, Tamil Nadu. The earliest major outbreak of the disease was in the year 1973, in Bankura district of West Bengal. There were 700 reported cases with nearly 300 deaths in that year. One of the worst outbreaks of JEV was observed in Gorakhpur, Uttar Pradesh in the year 2005 when around 5737 cases of JEV were reported resulting in 1344 deaths. Even as per government figures, there were a large number of deaths due to JEV in the year 2005.
Viruses are the main cause of Acute Encephalitis Syndrome (AES) as per Government assessment
Acute Encephalitis Syndrome (AES) is considered to be one of the serious health problems in India. Onset of fever results in inflammation of the brain and effecting the mental status causing delirium, disorientation, mental confusion and coma.
Linking the effects to a specific cause has always been a problem, while recording the cases. A note on the National Health Portal (NHP), attributes virus to be one of the major causes for AES related cases in India, with Japanese Encephalitis Virus being responsible for cases ranging from 5%-35% of the total cases every year.
Since the time JEV was recorded as the first case in 1955, most of the cases have been traditionally recorded as JEV. However, there have been multiple other reasons which are now being attributed for Acute Encephalitis. Currently, cases with these symptoms are being recoded as AES (Acute Encephalitis Syndrome). As per the note on the NHP, Bacteria, fungus, parasites, toxins, chemicals etc. are considered as few of the other main causes for AES in India.
Unlike the earlier outbreaks of AES, which were caused due to JE Virus, the recent outbreak in Bihar is considered to be a result of Hypoglycemia, a condition with low levels of blood sugar as well as imbalance in electrolytes.
Uttar Pradesh, West Bengal, Bihar & Assam among the most AES affected states
As per the data provided by National Vector Borne Disease Control Programme (NVBDCP), UP, Bengal, Assam, Tamil Nadu are among the states which have recorded the highest number of AES cases between January 2013 & April 2019.
A brief analysis of the data reveals that
- Uttar Pradesh accounts for nearly 32% of the total AES cases recorded in the country during this period
- West Bengal and Assam together account for another 33% of the total AES cases in the country during January 2013 & April 2019
Case Fatality Rate (CFR) for some states is alarming
Acute Encephalitis has been a recurring feature in these states every year, with many cases being recorded during May-June (summer season) of every year. The rapid deterioration of health in AES cases results in high CFR (Case Fatality Rate) if timely medical assistance is not provided. CFR is the number of deaths recorded per number of cases recorded.
While the number of AES cases recorded in these states in itself a matter of concern, CFR for few of the sates is alarming.
For instance, Bihar which ranks 6th in the number of AES cases (2697) during the period, has the highest CFR with 28.81% of the cases resulting in deaths i.e. 771 deaths.
States like Uttar Pradesh, Assam and West Bengal which report a high number of AES cases, also have high CFR with 15.07%, 13.95% and 12.96% of cases reported between January 2013 & April 2019 having resulted in deaths. Over this period, these three states have recorded a combined 6,174 deaths of which 3221 are from UP, 1512 from Bengal and 1441 deaths from Assam.
The four states of UP, West Bengal, Assam & Bihar account for 95.82% of the total deaths caused due to AES during this period.
Across India, a total of 7254 deaths were recorded since 2013 (till April 2019) out of 66,926 AES cases (i.e. CFR of 10.84%).
Tamil Nadu, Karnataka & Tripura among states to have better response to AES
The number of AES cases recorded in Tamil Nadu is the 5th highest in India during this period. As highlighted earlier, the first case of AES was recorded in Vellore district of Tamil Nadu.
However, the AES-CFR in Tamil Nadu is only 0.44 % with 22 deaths out of the 4964 recorded cases between January 2013 & April 2019.
Karnataka and Tripura are the other states with lesser CFR of 0.45% and 0.24% respectively. The number of AES cases recorded in these two states during this period are, 1784 and 2007 respectively.
Odisha, Manipur, Meghalaya and Jharkhand are among the states which also have less CFR in-spite of higher number of AES cases. Orissa has a bad year in 2015, with 115 of the 142 deaths recorded, occurring during that year.
Better response and facilities can reduce fatality
As per government’s note, there are multiple causes for AES in India. Research of various cases have revealed the reasons to be more complex and not limited to a single source. While Japanese Encephalitis Virus is considered to be one of the common causes, other virus like Influenza A, Herpes Simplex, West Nile, Chandipura etc. have also been identified as causes for AES.
There are also cases of the virus being transmitted through mosquitoes and other vectors. Few research reports, even point to toxins through food intake, which aggravate the situation for undernourished children.
The exact reasons for the outbreak of AEC around May-June every year are still not ascertained. However, it can be agreed that the prevalence is due to:
- Unhygienic conditions
While medical research can be carried out for identifying the reasons in each of the cases, efforts towards addressing the issues of Hygiene & nourishment can help to contain the impact and spread of AES outbreak.
As observed in the case of Tamil Nadu and other states, better responsive systems could help in reducing the number of deaths.
Featured Image: Acute Encephalitis Syndrome