From the Desk of Co-ordinator

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  Vaccinophilia: Boon or Bane

January 1, 2003 

Success story in the Smallpox eradication by vaccination has enthusiased the Health Administrators to look towards vaccines for disease control. For various reasons smallpox model could not be repeated in other infectious diseases. After decades of use of BCG vaccine, there are conflicting reports on its effectivity. With recent genomic comparisons, existence of different BCG Strains differing from the original BCG first used in 1921 was reported. Cholera vaccine is being used for short-term protection. The range of possible use of active immunization is rapidly expanding to include the vaccines against infectious diseases that require cellular responses to provide protection (e.g. TB, Leprosy) therapeutic vaccines for chronic infections (e.g. HIV, Hepatitis B and C) and vaccines against non-infectious conditions (e.g. Cancer). Vaccine use is being justified in terms of societal and parental “costs” (mandays lost) rather than in straightforward morbidity and mortality costs. Paediatric immunization schedule is becoming crowded. The National Immunization schedule includes BCG, DPT, Oral Polio and Measles vaccine besides DT and TT. Many more vaccines such as Typhoid, Hepatitis A, influenza viral vaccine are freely available in the country. However there is no clarity about who should exercise the option. In this confusion, the marketing strategy of drug firms is creating undue panic about certain diseases and promoting vaccine sales by giving incentives to prescribing clinicians. Thus hepatitis B is included in India’s Immunization programme. Efforts are to promote Hepatitis C and other Vaccines. Multinational drug firms are advertising number of vaccines as next best to a mother’s protection. Use of recombinant peptide vaccine without extensive evaluation and monitoring, is adding to the complexity of the problem. Relatively little is known about the immune pathogenesis of even best characterized vaccine-associated adverse events (VAAE) causing considerable concern regarding indiscriminate use of vaccines. Report from BBC News provided a timely warning that “weak vaccines strengthen disease”. In case of chronic diseases such as malaria, vaccines that are less effective have the potential to do more harm than good in creating more virulent forms of the disease. There is a feeling that not every infection need to be prevented by vaccination.
          Each living organism is endowed with survival instinct when it comes into universe. It is empowered to survive against odds and unhelpful environment. It is important not to disturb the immune balance. We have to be exposed to certain number of infections in our life time and particularly during infancy. Systemic prevention of these exposures may not benefit the individuals or the species in long  run.All this brings us to sit and objectively think about the use of the vaccine in cool mind before we are driven by market forces and made helpless.
          Leaving vaccines to commercial interests will not serve the interest of humanity. WHO study has reported how industry sponsors can influence clinical trials to produce desired results. There is an urgent need for the extensive study on the identification of vaccines which are essential for prevention or therapy, long term monitoring on effectivity, adverse vaccine reactions and quality control. Vaccine for each organism, strain and sub strain is not justified. Attempts should be made to develop a vaccine to produce broad protection against number of infective organisms.

January 1, 2003                                                                                                                                  

Dr. B.C. Harinath  
Director JB Tropical Disease Research Centre &
 Coordinator Bioinformatics Centre

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  April 1, 2003

Manipulation of Gene – Boon or Bane

                Genetically modified organisms (GMOS), in particular microbes are being routinely used in the production of therapeutics. Recombinant bacterial products such as human insulin, plasminogen activator, interleukins, interferons are finding different clinical uses. Similar to bacteria, GM crops are also coming up very fast in agriculture with several genes available for designer crops. These crops are supposed to be endowed with higher yields, nutritional quality and resistance to insects and pests. Herbicide-resistant sugarbeet, insect-resistant cotton and tomato are in commercial use. In animal husbandry too, GM animals are on their way with designer eggs, salmon fish with human growth hormone, fast growing catfish, oysters subject to regulatory approval for human consumption. People are concerned with MNC controlled high-technology and commerce driven GM food for its safety and long term effects on human health and on the ecological environment. The merits of gene-tech insulin verses natural insulin are being debated.   Dr. Teuscher, Founder President of the Swiss association for the preservation of natural insulin and other experts say as many as 10 to 20% of gene-tech insulin users can encounter a variety of such side effects, collectively termed as ‘hypoglycemia unawareness’ leading to death in diabetics during sleep due to severe blood sugar drop. (U.S. FDA rules require a warning about  hypoglycemia to be printed on package). As production of natural insulin is more expensive, insulin producers are switching to gene-tech variety. Another example is that of genetically modified crop, the BT cotton. The first crop’s indifferent performance in Maharashtra, Gujrat, Karnataka and Andhra Pradesh has been disappointing, possibly due to lack of field studies in real field situation compared to optimal conditions in experimental fields. The BT cotton seed is costlier compared to good hybrid seeds and caused heavy losses to the farmers. Suman Sahai, President, Gene compaign, questions the clearance and introduction of the GM crop by Mahyco-Monsanto without thorough study on its suitability to Indian conditions and long term implications. These experiences teach us to tread cautiously while working with manipulation of genes and introducing GM foods into normal diets, without surrendering to aggressive marketing strategies of MNCs.

April 1, 2003                                                   

Dr. B.C. Harinath  
Director JB Tropical Disease Research Centre &
 Coordinator Bioinformatics Centre

July 1, 2003  

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Human Genome Sequencing and After

Human Genome Sequencing is complete – announcement was made by the leaders of a Public Consortium of academic centres at the National Institutes of Health in April, 2003. The project initiated in 1990 was expected to take 15 yrs. It has been completed two years ahead of schedule, thanks to automation and bioinformatics. The announcement was timed to coincide with the 50^th anniversary of the discovery of the structure of DNA by Watson and Crick. The unfolding of human genome with about 3 billion base pairs arrayed in 23 chromosomes costing about $800 million, is exciting enough to push biology into Biotechnology with great expectations in diagnostics, vaccines, new drugs, gene therapy and cloning. It is interesting to note that only less than 5% of DNA with 30000 genes codes for proteins. More than 95% of DNA is non coding and possibly involved in regulation of gene expression during development, differentiation and adaptation to environment.  All humans have the same DNA to the extent of 99.9 percent, the 0.1% making the difference between the female and male, young and old, intelligent and dullard, aggressive and mild, normal and disabled thus emphasising the  importance of understanding of DNA organization, regulation of expression, suppression and environmental adaptation. Comparative Genomics have shown that humans share 98% of their genetic sequence with monkeys and 57% with cabbage. The humble weed plant, Thale cross (Arabidopsis thaliana) has 30% of genes with notable similarities to humans. A long and difficult path is ahead.  The genetic polymorphism, function of non coding DNA, regulation by biomolecules, proteomics are the challenging areas in the coming years to understand the nature and explain growth, differentiation, behavior and environmental adaptation.