National Institute of Cholera and Enteric Diseases.
Keywords: Academies and Institutes, organization &administration,Cholera, epidemiology,therapy,Gastrointestinal Diseases, epidemiology,therapy,Human, India, epidemiology,
Eastern India, notably the Gangetic belt is considered as the “homeland” of cholera and a focal point of many of the epidemics and some of the pandemics. A great deal of work had already been done but there were many unturned chapters on cholera that motivated the Indian Council of Medical Research (ICMR) to establish a renewable temporary set up of “Cholera Research Centre” (CRC) at Calcutta in 1962. The Centre has been given the status of “International Reference Centre for Vibrio Phage Typing” by the WHO in 1968 and later on redesignated as the “WHO Collaborative Centre for Reference and Research in Vibrios” in 1978 for providing referral services to the member countries. With continuing advancement of the centre the ICMR changed this temporary research Centre into “National Institute” and renamed as “National Institute of Cholera and Enteric Diseases” (NICED) in 1979. The WHO recognised this Institute as “WHO Collaborative Centre for Research and Training on Diarrhoeal Diseases” in 1980.
NICED deals with diarrhoeal diseases of diverge aetiologies, typhoid fever, infective hepatitis and AIDS. Aims of this Institute are to conduct research on those diseases on both basic and applied aspects. Institute aims to train the professionals for better management and prevention of diarrhoeal diseases and also for rapid and correct diagnosis. Epidemiological investigations of epidemics of diarrhoeal diseases are being carried out in different parts of India from time to time. Antisera of Vibrio cholerae is raised in this Institute and supplied to national and International laboratories. Specific monoclonal antiserum for detection of Vibrio cholerae O139 strains was developed at NICED which has been supplied to WHO (SEARO), New Delhi for distribution to various national and International laboratories. As WHO Phage Reference Centre, Institute receives a large number of Vibrio cholerae strains from all over the world for Phage typing.
Though this Institute is principally financed by the ICMR, New Delhi, other funding agencies are also financing the Institute for collaborative research work.
The Japanese International Co-operative Agencies (JICA) has established a collaborative research establishment in this Institute to work on in-depth molecular aspects of different enteropathogens with special emphasis to Vibrio cholerae O1 and O139. Department of Biotechnology (DBT), Government of India supports different projects on basic research. The WHO and UNICEF also support the projects on applied research.
Several workshops on management and preventive aspects of diarrhoeal diseases and on rapid screening methodology of different enteropathogens have been sponsored by WHO, UNICEF, DBT and Ministry of Health and Family Welfare, Govt. of India.
Each year 4-5 post-graduate students of this Institute receive PhD degree from the different Universities of the State. Post-graduate medical students also attend the Institute for training on diarrhoeal diseases and also to get scientific assistance from the scientists who work as co-guides for their MD thesis. WHO and JICA send their international fellows to receive training on diarrhoeal diseases.
Studies on cholera
• Epidemiological differences between El Tor and classical varieties of cholera.
• Studies showed a lower incidence of cholera carriers among contacts of cholera affected houses provided with narrow necked pitchers and demonstrated the effectiveness of simple measures like hand washing with soap and water, coupled with health education.
• Studies showed that chemoprophylaxis has little role in the control of cholera carriers in endemic areas.
• Controlled field trials of conventional cholera vaccine and aluminium adjuvant cholera toxoid vaccine were carried out by this Institute which revealed limited protection.
• A new phage typing scheme for Vibrio cholerae biotype El Tor strains has been developed at NICED, which is useful as an epidemic marker for tracing the sources of infection.
• Studies showed for the first time that ORS if given in small quantity and at regular frequent intervals, vomiting can be avoided. Further studies demonstrated that ORS of WHO formula is safe and effective in the treatment of dehydrating acute diarrhoea in neonates and severely malnourished children.
• Studies on newer forms of ORS: Glycine fortified ORS showed no added advantage over standard ORS. Cereal based ORS showed reduction of stool volume and duration of diarrhoea. Presently studies are continuing with “hypo-osmolar ORS” in cholera and non-cholera diarrhoea.
• Scientists at NICED showed that single dose of doxycycline (300 mg) is effective alternative to tetracycline for the treatment of adult El Tor cholera. It was documented that norfloxacin is as effective as tetracycline for the treatment of cholera in adults. The WHO has recommended doxycycline for adult cholera.
• Purification and molecular characterisation of Vibrio cholerae lectins was done. A cell free hemagglutinin (HA) was isolated and purified. The cell associated HA has also been characterised biochemically, morphologically and antigenically.
• During 1992-93, when a new toxigenic non-O1 cholera strains, designated as Vibrio cholerae O139 Bengal appeared, scientists of NICED have the credit of bringing this information to the notice of global scientific community. The NICED has done substantial research related to Vibrio cholerae O139 in the areas of microbiology, clinical medicine and epidemiology.
Studies on Shigella
• The NICED has done epidemiological research during epidemics of shigellosis in different parts of the country and has also shown the efiicacy of various antimicrobials in the treatment of shigellosis.
• The humoral immune response of patients convalescing from shigellosis, against bacterial components like lipopolysaccharide (LPS) and outer membrane proteins has been analysed.
Studies on Rotavirus
• Studies conducted at NICED documented that Rotavirus was detected as sole pathogen in 22% of hospitalized children suffering from diarrhoea in Calcutta. However, in Manipur, the detection rate of Rotavirus was as high as 90% in the winter months. Long electropherotype but subgroup 1 Rotavirus was detected from cases which suggested the zoonotic transmission of Rotavirus in Manipur. Genetically this strain was related to the human VP 7G serotype 2 strain but antigenically reacted to bovine VP 7G serotypes 6 and 10 but not with any known major human VP 7G serotypes 1 to 4. This study suggested that the strain might have developed by in vivo reassortment between human and bovine Rotavirus.
• Recently, a human group B Rotavirus, CAL strain was detected for the first time outside China by the scientists of NICED.
Apart from these the NICED has conducted large number of studies dealing with epidemiology, clinical aspects and microbiology including the molecular basis of diarrhoeal diseases due to Vibrio parahaemolyticus, E.coli , intestinal parasites and other enteropathogens and enteric fever.
For discovery of a novel epidemic strain of Vibrio cholerae serogroup O139, synonym Bengal and non-membrane damaging cytotoxin (NMDCY) among Vibrio cholerae strains, Dr. G. Balakrish Nair, Deputy Director of this Institute was awarded the prestigious Shanti Swarup Bhatnagar Award for excellence in Medical Sciences for the year 1998 by the Council of Scientific and Industrial Research (CSIR).