Epidemiological situation of Japanese encephalitis in Nepal.

A human Japanese encephalitis (JE) case is considered to have elevated temperature (over 380 C) along with altered consciousness or unconsciousness and is generally confirmed serologically by finding of specific anti-JE IgM in the cerebro spinal fluid. No specific treatment for JE is available. Only supportive treatment like meticulous nursing care, introduction of Ryle's tube if the patient is unconscious, dextrose solution if dehydration is present, manitol injection in case of raised cranial temperature and diazepam in case of convulsion. Intra venous fluids, indwelling catheter in conscious patient and corticosteroids unless indicated should be avoided. Pigs, wading birds and ducks have been incriminated as important vertebrate amplifying hosts for JE virus due to viremia in them. Man along with bovines, ovines and caprines is involved in transmission cycle as accidental hosts and plays no role in perpetuating the virus due to the lack of viremia in them. The species Cx tritaeniorhyncus is suspected to be the principal vector of JE in Nepal as the species is abundantly found in the rice-field ecosystem of the endemic areas during the transmission season and JE virus isolates have been obtained from a pool of Cx tritaeniorhyncus females. Mosquito vector become infective 14 days after acquiring the JR virus from the viremic host. The disease was first recorded in Nepal in 1978 as an epidemic in Rupandehi district of the Western Development Region (WDR) and Morang of the Eastern Region (EDR). At present the disease is endemic in 24 districts. Although JE as found endemic mainly in tropical climate areas, existence and proliferation of encephalitis causing viruses in temperate and cold climates of hills and valleys are possible. Total of 26,667 cases and 5,381 deaths have been reported with average case fatality rate of 20.2% in an aggregate since 1978. More than 50% of morbidity and 60% mortality occur in the age group below 15 years. Upsurge of cases take place after the rainy season (monsoon). Cases start to appear in the month of April - May and reach its peak during late August to early September and start to decline from October. There are four designated referral laboratories, namely National Public Health Laboratory (Teku), Vector Borne Diseases Research and Training Center (Hetauda), B.P. Koirala Institute of Medical Sciences (Dharan) and JE Laboratory (Nepalgunj), for confirmatory diagnosis of JE. For prevention of JE infection; chemical and biological control of vectors including environmental management at breeding sites are necessary. Segregate pigs from humans habitation. Wear long sleeved clothes and trousers and use repellent and bed net to avoid exposure to mosquitos. For the prevention of the disease in humans, safe and efficacious vaccines are available. Therefore immunize population at risk against JE. Immunize pigs at the surroundings against JE. 225,000 doses of live attenuated SA-14-14.2 JE vaccine were received in donation from Boran Pharmaceuticals, South Korea for the first time in Nepal. Altogether 224,000 children aged between 1 to 15 years were vaccinated in Banke, Bardiya and Kailali districts during 1999. From China also, 2,000,000 doses of inactivated vaccine were received in 2000 and a total of 481,421 children aged between 6m to 10 yrs were protected from JE during 2001/2002. Ministry of Agriculture, Department of Livestock Services has vaccinated around 200,000 pigs against JE in terai zone during February 2001.

Tonsillar microbial flora: a comparison of infected and non-infected tonsils.

OBJECTIVE: The main objective of this study was to find out the most common organism affecting the tonsils in recurrent tonsillitis. METHODOLOGY: This was a prospective study consisting of total number of 50 patients, conducted in the ENT department of Dhulikhel Hospital, KUTH, Dhulikhel, Nepal. The study period was one year and three months (March 2004 to April 2005). RESULTS: Total numbers of 50 patients were selected, of which 32 were of acute tonsillitis and 18 were taken as control. Among these males were 32 and females were 18. The age group was from 3 years to 64 years. Throat swabs of patients were taken by aseptic method and were sent to the laboratory immediately. Among the infected tonsils the most common organism was Streptococcus viridans followed by Streptococcus pneumoniae and Moraxella catarrhalis. The third most common was Beta haemolytic streptococci whereas Micrococcus was not isolated in any of the infected samples. Likewise in non-infected tonsils, the most common organism isolated was again Streptococcus viridans followed by Micrococcus and Diptheroids. In these specimen no Beta haemolytic streptococci was isolated from the control group. CONCLUSION: Thus, the study is able to put forward the fact that most common organism affecting the tonsils in infected as well as non- infected state is Streptococcus viridans. Where as Beta haemolytic streptococci was not found in non-infected tonsils, likewise Micrococcus was not found in infected tonsils.