Review on Japanese Encephalitis Outbreak Cases in Nepal During the Year 2011

Nepal is one of the richest countries in the world in terms of bio-diversity due to its unique geographical position and altitudinal variation. The elevation of the country ranges from 60 m above sea level to the highest point on earth, Mr. Everest at 8,848 m, all within a distance of 150 km resulting into climatic conditions from subtropical to artic mentioned by Nepal Tourism Board, 2006. JE cases are observed mostly in Terai area (The lowland plains of the Terai lie at an altitude of between 67 and 300 m (220 and 980 ft tropical climate) (Joshi, 1983). In Southeast Asia it is thought to cause up to 50000 clinical cases and 10000 deaths per year (WHO/SEARO, 1979). The earlier reports have shown that the case fatality rate (CFR) is high in Nepal, and nationwide it has ranged from 15% to 46% for the years 1978 to 1994. There are 75 districts, 14 zones and five development regions in Nepal. Out of 75 districts 36 dis‐ tricts are affected by Japanese encephalitis.


Introduction
Nepal is one of the richest countries in the world in terms of bio-diversity due to its unique geographical position and altitudinal variation. The elevation of the country ranges from 60 m above sea level to the highest point on earth, Mr. Everest at 8,848 m, all within a distance of 150 km resulting into climatic conditions from subtropical to artic mentioned by Nepal Tourism Board, 2006. JE cases are observed mostly in Terai area (The lowland plains of the Terai lie at an altitude of between 67 and 300 m (220 and 980 ft tropical climate) (Joshi, 1983). In Southeast Asia it is thought to cause up to 50000 clinical cases and 10000 deaths per year (WHO/SEARO, 1979). The earlier reports have shown that the case fatality rate (CFR) is high in Nepal, and nationwide it has ranged from 15% to 46% for the years 1978 to 1994. There are 75 districts, 14 zones and five development regions in Nepal. Out of 75 districts 36 districts are affected by Japanese encephalitis.
Japanese encephalitis (JE) has been occurring in the South-East Asia and Western Pacific Regions for a long time. In Nepal, it has occurred first time in Rupandehi district then in Sunsari, Morang and latter in all 23 districts of Terai and inner Terai (Joshi, 1983). Incidence of this disease has been recorded first time in different years in the following countries. Japan, China and Republic of Korea have reduced the incidence of this disease now (WHO/SEARO, 1979).
These mosquitoes can breed in sub-urban and peri-urban area provided the ecological conditions similar to rural area are present (Pradhan, 1981, Khatri et al., 1981, 1983. These mosquitoes can breed same environment wherever it is favourable. In Nepal JE has been recorded and reported as a seasonal disease in Nepal. "Shrawan" (July and August) appears to have been the deadliest month for the Nepalese as far as human casualties from JE are concerned.

Japanese encephalitis distribution in Nepal
This JE virus is transmitted through a series of bites -when the mosquito bites a pig, for instance, it transmits the virus to the pig which acts as a host to the virus. The virus is further transmitted to humans when bitten by mosquitoes who have already bitten the pig.
The virus attacks the central nervous system of human, causing encephalitis-an infection of the brain. The patients starts vomiting, suffers severe headache and fever gradually becomes unconscious and nears death due to brain swelling. Even if the patients survive they remain with a lot of deflect-both physical and intellectual. Such a deadly disease, so wide spread in Nepal and without a cure. Preventing mosquito bite is thus so very important. But unlike for dengue virus, there is a vaccine for Japanese B virus which the government is trying to make available in mass. Japanese encephalitis virus also called Japanese B virus.
The mosquitoes that transmit this disease breed in and around dirty, stagnant water and in areas where the pigs are farmed. We all know that there are many places in and around Kathmandu that fits into this description, so I would urge you to hurry and get vaccinated. Another disease Filarisis-is also transmitted through the disease vector that is the female Culex mosquito. Filariasis is spread from infected persons to uninfected persons by mosquitoes that release large numbers of very small worm larvae, which circulate in an affected

Epidemiological cycle of Japanese encephalitis
Japanese encephalitis (JE) is caused by a Flavivirus that, in a human case, causes severe encephalitis leading to death or permanent disablement. It is a zoonotic disease, transferred from animals (commonly domestic pigs but wild boars and migratory birds may also be important amplifier hosts and reservoirs) by a mosquito vector to humans. Important social factors may also play an important role in JE transmissions with the poorest sectors of the population most often affected (e.g. people sleep outside during hot humid months where the vector density is at peak, and often sleep close to pigs). JE has been occurring in the South-East Asia and Western Pacific Regions for a long time. In Southeast Asia it is thought to cause up to 50000 clinical cases and 10000 deaths per year (WHO, 1979). Japan, China and Republic of Korea have reduced the incidence of this disease now (WHO/SEARO 1979). These countries had very well developed long term plan to control the epidemicity of JE by regular vaccination in children and pigs they had also improved pig husbandry system and also vector control by draining the water from the rice field on a regular interval period.
JE cases are observed mostly in Terai region of Nepal (Joshi, 1983). The earlier reports have shown that the case fatality rate (CFR) is high in Nepal, and nationwide it has ranged from 15% to 46% for the years 1978 to 1994 (Joshi, 1983, 1986, 1987, Joshi et al., 1994. In Nepal, JE occurred first time during the year 1978 in Rupandehi district then in Sunsari, Morang and has since become endemic in all 24 districts of Terai and Inner Terai (Joshi, 1983

District (province) wise JE cases recorded during the year 2011:
Bhaktapur District

Bhaktapur hospital sees surge in Japanese encephalitis (viral fever) patients
The number of viral fever patients has increased in most of the hospitals in Bhaktapur district coinciding with the change in weather. Many people suffering from viral fever have been coming to the hospitals and health centre in the district. Along with the upsurge in the number of viral fever patients, the number of people suffering from typhoid and jaundice has also increased according to the District Public Health Office, Bhaktapur.
Superintendent at the Bhakatapur Hospital, Dr. Indra Prajapati said the diseases might take epidemic proportion if timely measures are not taken. Health Official in the district say the spread of viral fever is also because patients in the rural areas of the district have the habit of only taking paracetamol tablets that they buy at local drug stores instead of visiting the doctors for a thorough check-up. As many as 100 people suffering from fever come to the Bhaktapur Hospital daily for treatment, and many of them only after advanced stage of the INFLUENZA AH3 virus has been linked with a viral fever outbreak in Chitwan, health officials said. Blood samples collected from various parts of the district tested positive for the Influenza AH3. Ram Kumar KC of the vector control programme of District Public Heath Office (DPHO) said apart from influenza AH3, Japanese encephalitis was also detected in some patients.
"We didn't have any encephalitis case last year," he said. According to the DPHO, over 1,500 people suffering from viral fever visited major hospitals in Chitwan in the last three weeks.
Most of the patients were in the 16-50 years age bracket. Health officials warned that the number of patients could rise in the coming days.

Japanese encephalitis (viral fever) grips Pokhara
The pressure of patients at Western Regional Hospital and health posts in Pokhara is alarmingly increasing owing to flu of typhoid and viral fever for past few days. Among the total number of the patients visiting the health posts, 35-40 per cent of them are suffering from typhoid and viral fever, said the hospital.
Buddhi Bahadur Thapa, Medical Superintendent of the hospital said the number of typhoid and viral fever patients increased during the change of season. Most of the patients are suffering from fever, cough and common cold, he added.
As the infection of common cold and fever increasing across the district, the number of patients visiting the private hospitals and taking medicine from pharmacies are increasing from the past few days. Informing that some patients who suffer from the viral fever also picked up asthma, diabetes and heart related problems. Thapa said that the people who got infected the immediate medical treatment.
Doctors informed that Padam Nursing Home, Charak Hospital and Fewa City Hospital registered the large number of patients. Thapa said that as the viral fever was a communicable disease, many persons were easily infected with the flu. Since last few days the people of Syangja, Tanahu, Parbat, Lamjung and other adjoining districts have been suffering from the viral fever and typhoid and the flu is developing into the pandemic.
When the local hospitals of these districts couldn't stand the pressure of the patients, they rec-

Japanese encephalitis (viral fever) and Pneumonia outbreak
Arghakhanchi, District hospital was fully occupied due to large number of viral fever and pneumonia cases. Due to large number cases and lack of beds, patients are being treated on floor.
Patients have admitted forty to fifty within one week of time. There are only 15 beds but 40 to 50 patients are sick, hospital informed that more than 30 patients are being treated on the floor. Children are sicker than other age group; this age groups belong to 1 to 2 yrs. According to Chief, Acting District Hospital Dr. Ram Prasad Sapkota, viral pneumonia patients are more in hospital. He told that it has been difficult to doctor and medical people because of full of patients in hospital. He added that more than 100 patients are being treated in OPD on Sunday. Patients complained that lack of bed, more patients treated and patients are brought for hospital for treatment and they have to stay in hotel. 25 pneumonia patients are admitted in hospital daily. Patients are coming from not only headquarter but also from urban areas for treatment. CMA told that patient flow rate is increased more in health and sub-health post in VDC. Four doctors complained that they are faced problem due to outbreak of disease. Dr. Sapkota told that lack of bed, pneumonia patients are treated lying on the floor. He added more that patients are increasing day by day and most of the patients are seriously due to form pneumonia and viral fever, they came to hospital for treatment. (Source: Kantipur, September 26, 2011) Dang District

Pig farming ban in Dang
Pig farming has been banned inside the Tribhuvannagar Municipality area. The ban was levied by the municipality in wake of the spreading out of the Japanese encephalitis in the Terai region. The ban is effective within Chbhaisota in the north, Ratnapur-Bharatpur road in the South, Runway-Bharatpur in the east and Sewar River in the west. The municipality has also begun killing the stray pigs and ducks that are left unclaimed even after repeated request to the owners to get rid of them, said Mayor Amar BahadurDangi. The Nepal Bank Ltd., Agriculture Development Bank and other financial institutions have also been requested not to issue loans for pig farming in the region, adds Dangi. The municipality has so far killed 40 pigs and two ducks found unclaimed in various wards of the municipality, it is learnt (Source: Rising Nepal, July 5, 2002).

JE stalks mid-western Terai district
Japanese encephalitis, a mosquito-borne viral disease, has stalked the mid-western Terai districts lately, claiming one life and taking scores others ill. Gumi Rana of Chaulahi from Dang district died of Japanese encephalitis on Monday while undergoing treatment at Nepalgunj based Bheri Zonal Hospital. The hospital sources said the flow of encephalitis patients is surging in recent days. According to Dr. Bimal Dhakal, the chief at the hospital, 11 Japanese encephalitis patients have been admitted to the hospital in the past one month and some of them are still receiving treatment. The hospital data shows that most of the patients are form Dang, Banke and Bardiya districts. Mid-western Terai districts come under the grip of fatal Japanese encephalitis during the monsoon every year. Last year, 105 Japanese encephalitis patients were admitted to Bheri Zonal Hospital and 23 of them died of the disease. Dr. Dhakal is of the opinion that the fatal disease is beyond control due to the lack of public health awareness. Ram Bahadur Chand of District Public Health Office Banke, however, claimed the office has been working to prevent the spread of the disease. Please use Adobe Acrobat Reader to read this book chapter for free.
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across Rapti river areas. Insecticides could not be sprayed due to heavy rains, he agreed. Insecticide will be sprayed after cease of rain. According the public health office, JE regular vaccine is giving under one year child to control the JE. JE is controlled due to vaccine. Doctor advised that, people have to use bed net regularly, clean and cut unnecessary bushy and make tidy filling water ditch to save from JE disease. Altogether 105 JE patients were admitted out of which 23 patients were died in Bheri Zonal Hospital last year.

More one dead due to JE
Banke: more one kid dead due to JE, 7 -Sorhawa, Bardiya 7 -years old AsmitaChaudhari was dead during treatment period and 3 were dead due to JE before. JE cases are raised and 33 persons are admitted in Bheri Zonal Hospital till Tuesday. According to hospital source, patients are also admitted in Nepalgunj and Kohalpur.
According to Director Bimal Dhakal, patients flow like encephalitis disease is raising. Child ward is fully occupied. According to hospital source, most of patients have come from Bardiya districts. Nine patients from Berdiya, 7 from Banke, 7 dang, 1 Jajarkot, 8 Kailali, 1 Salyan and 1 from Surkhet are admitted.

Discussion
The earlier reports have shown that the case fatality rate (CFR) is high in Nepal, and nationwide it has ranged from 15% to 46% for the years 1978 to 1994 . It has been proved that JE virus causes encephalitis in humans and abortion in pigs while no symptoms in other animals and birds. Mostly children aged five to fifteen is victimized than adults. About fifty percent of the JE survivors are left with neurological syndrome and damage to the organs (Joshi, 1983, Pradhan, Khatri et al., 1981, 1983.
The people in the districts are dying due to Japanese encephalitis, and it threatens to assume epidemic proportions. The government has just started its second round of vaccination under mass vaccination program for the disease, which should have been completed by 2006. Because of the delay in vaccination, the number of patients suffering from Japanese Encephalitis may increase and take an epidemic form.
The vaccine "anti JESA-14-14-2 live attenuated" is produced in China and that it was found to be above 98 percent effective in Chinese children (RSS, 2006). In Nepal, some two million people live in the Terai regions considered to be highly affected areas. In order to prevent the epidemic, more than three million doses of vaccines had been arranged during the year 2005.
Vaccination campaign against Japanese encephalitis has been started in Banke district from 26 July 2006. It is said that all 422,000 people above one year of age from Banke district were vaccinated in the campaign, which would continue until August 18, 2006. The full doze vaccine has been provided by the district public Health office. According to the schedule, the campaign would remain until July 17, 2006 in Nepalgunj municipality and from July 27 to August 18, 2006 in 46 VDCs of the districts (JE vaccination report of Banke, 2006).
The reduction in case incidence of Japanese encephalitis, in some countries like China, Japan and Korea has been achieved by applying certain measures such as:

i.
Mass vaccination of susceptible group of population,

ii.
Vaccination of piglets of endemic areas,

iii.
Anti-mosquito campaign, i.e. vector control measure both larva and adult.

Encephalitis 68
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Conclusion
For the reduction of JE cases in Nepal mass vaccination programme should be carried out every year for children in high risk districts of JE. Except symptomatic treatment there is no specific treatment for Japanese encephalitis. There is a Japanese encephalitis vaccine prepared in Japan, China and Rusia. There are two types of vaccines one liquid and other freeze dried. Vaccination can be done subcutaneously two doses of 1 ml each above 3 years of age and 0.5 ml. For children upto 3 years of age at an interval of 7-14 days. Third doses should be given before one year. This will protect for 3 years in the endemic zone. One more booster dose after 3 years has been recommended which will give life long immunity to an individual (Joshi et al., 2003).
To conclude, mosquito borne disease is on the rise. There are many methods for mosquito control and depending the situation, source reduction (e.g., removing stagnant water) biocontrol (e.g. importing natural predators such as dragonflies), trapping, using nets and using pesticides can be helpful. In endemic areas, there should be spraying of insecticides every day. People should stay inside between dusk and dark if possible. When outdoors, wearing pants and long-sleeved shirts is a must. Exposed skin should be sprayed with mosquito repellants (Neopane Arpana, 2011).