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Bright future for nuclear medicine
welcome, careful surveillance, before, during, and after its introduction is essential to detect any increase in the carriage of non-serogroup C hypervirulent meningococci—particularly those belonging to the ET-37 complex. Carriage studies should be done among the 15–17 age-group—ie, those with high rates of carriage and who are to be included in the first round of vaccination.As the vaccine is soon to be introduced, procedures to obtain prevaccination baseline samples of the meningococcal population should be implemented as a matter of urgency. Although such studies will have to be large, they are possible with current strain-characterisation technology6 and will require only a fraction of the resources necessary to implement the vaccination programme. Finally, efforts to find a comprehensive meningococcal vaccine must be maintained and, in the absence of such a vaccine, continued public-health education about the importance of early recognition and treatment of meningococcal disease should remain a priority. *Martin C J Maiden, Brian G Spratt Wellcome Trust Centre for the Epidemiology of Infectious Disease, Department of Zoology, University of Oxford, Oxford OX1 3FY, UK 1
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MacDonald NE, Halperin SA, Law BJ, Forrest B, Danzig LE, Granoff DM. Induction of immunologic memory by conjugated vs plain meningococcal C polysaccharide vaccine in toddlers: a randomized controlled trial. JAMA 1998; 280: 1685–89. Stephens DS. Uncloaking the meningococcus: dynamics of carriage and disease. Lancet 1999; 353: 941–42. Maiden MCJ, Feavers IM. Population genetics and global epidemiology of the human pathogen Neisseria meningitidis. In: Baumberg S,Young JPW, Wellington EMH, Saunders JR, eds. Population genetics of bacteri a .C a m b ri d g e :C a m b ridge University P r e s s ,1 9 9 5 :2 6 9 – 9 3 . Vedros NA. Development of meningococcal serogroups. In:Vedros N A ,e d .E volution of meningococcal disease. Boca Rat o n ,F L :C R C Press Inc, 1987:33–37. Racoosin JA,Whitney CG, Conover CS, Diaz PS. Serogroup Y meningococcal disease in Chicago, 1991–1997. JAMA 1998; 280: 2094–98. Maiden MCJ, Bygraves JA, Feil E, et al. Multilocus sequence typing: a portable approach to the identification of clones within populations of pathogenic microorganisms. Proc Natl Acad Sci USA 1998; 95: 3140–45. Caugant DA ,K ristiansen BE, Froholm LO, Bovre K, Selander RK. Clonal diversity of Neisseria meningitidis from a population of asymptomatic carriers. Infect Immun 1988; 56: 2060–68. Wang J-F, Caugant DA, Morelli G, Koumaré B, Achtman M. Antigenic and epidemiological properties of the ET-37 complex of Neisseria meningitidis. J Infect Dis 1993; 167: 1320–29. Vogel U, Morelli G, Zurth K, et al. Necessity of molecular techniques to distinguish between Neisseria meningitidis strains isolated from patients with meningococcal disease and from their healthy contacts. J Clin Microbiol 1998; 36: 2465–70. Raymond NJ, Reeves M, Ajello G, et al. Molecular epidemiology of sporadic (endemic) serogroup C meningococcal disease. J Infect Dis 1997; 176: 1277–84. Takala AK, Santosham M, Almeido-Hill J, et al. Vaccination with Haemophilus influenzae type b meningococcal protein conjugate vaccine reduces oropharyngeal carriage of Haemophilus influenzae type b among American Indian children. Pediatr Infect Dis J 1993; 12: 593–99. Slack MP, Azzopardi HJ, Hargreaves RM, Ramsay ME. Enhanced surveillance of invasive Haemophilus influenzae disease in England, 1990 to 1996: impact of conjugate vaccines. Pediatr Infect Dis J 1998; 7: S204–07. Lipsitch M. Bacterial vaccines and serotype replacement: lessons from Haemophilus influenzae and prospects for Streptococcus pneumoniae. Emerg Infect Dis 1999; 5: 336–45. Gupta S, Galvani A. The effects of host heterogeneity on pathogen population structure. Philos Trans R Soc Lond B Biol Sci 1999; 354: 711–19. Kwara A, Adegbola RA, Corrah PT, et al. Meningitis caused by a serogroup W135 clone of the ET-37 complex of Neisseria meningitidis in West Africa. Trop Med Int Health 1998; 3: 742–46. Obaro SK, Adegbola RA, Banya WA ,G r e e n wood BM. Carriage of pneumococci after pneumococcal vaccination. Lancet 1996; 348: 271–72.
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Bright future for nuclear medicine See page 661 It was my good fortune to meet one of the founders of nuclear medicine, the late Glenn Seaborg, at the annual meeting of the Society of Nuclear Medicine in June,1996. He was keen as ever to discuss the future of nuclear medicine and was particularly interested in contacting the Commission on Nomenclature of Inorganic Chemistry, and not without reason. Glenn Seaborg was involved in the discovery of iron-59, iodine-131, cobalt-60, and technetium-99m. Element 106 is now named Seaborgium. In 1951, he, with Edwin McMillan, was awarded the Nobel Prize in chemistry. Several eminent scientists who applied the radioactive-tracer principle have also been Nobel laureates: Becquerel and the Curies (Physics, 1903); von Hevesy (Chemistry, 1943, for the first radiotracer study in animals); and Yalow (Medicine, 1977) for her work with Berson on the radioimmunoassay. Development in nuclear medicine has always been along two lines—clinical service, for diagnosis and therapy, and basic research, aimed at unravelling disease mechanisms, pathways of drug interaction, and early assessment of individual organ function. The large variation in practice worldwide reflects this duality and, naturally, the funding of the specialty. In the bigger medical institutions, large teams branch out into the different areas of application and research. In smaller centres, a simple but effective clinical service emerges. There is a world of difference between the complexity of a bone scan and tomographic maps of receptors, and between treatment of thyroid diseases with radioiodine and specific treatment of a lymphoma with a labelled, monoclonal antibody. The availability of nuclear medicine is hence non-uniform; some European countries do more than 50 000 procedures per million population whereas the frequency in others is about 10 000 per million. The attraction of nuclear medicine is strong. The detection of biological signals at the picomolar level, associated with specificity of the ligand in question, explains the interest and the potential. The methods are uniquely suited to tissue characterisation, to early assessment of the extent and severity of disease, and finally to treatment of disease with specific ligands. And yet over-regulation is posing possibly the biggest threat to its expansion. The estimation of risks involved is not proportional to the vast body of legislature that begins to impact on progress. The cost of registration of new radiopharmaceuticals is clearly deterring industry and sponsors alike. A tracer delivered once or twice to an individual in quantities of less than a milligram (often in the nano or picomolar range) will require, for registration purposes, the imprimatur of a body of legislation basically designed to monitor the side-effects of drugs, given commonly daily in doses of hundreds of milligrams. The series of six articles on nuclear medicine that The Lancet begins today describe the wide clinical applications, potential, and future developments. Nuclear medicine has offered new insights in the understanding of the dementias, the spread of cancer, and the early detection of coronary-artery disease. Not all potential applications could be covered in this series. There is, however, ample food for thought. Peter J Ell Institute of Nuclear Medicine,University College London Medical School, Mortimer Street,London W1N 8AA,UK
THE LANCET • Vol 354 • August 21, 1999
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MacDonald NE, Halperin SA, Law BJ, Forrest B, Danzig LE, Granoff DM. Induction of immunologic memory by conjugated vs plain meningococcal C polysaccharide vaccine in toddlers: a randomized controlled trial. JAMA 1998; 280: 1685–89. Stephens DS. Uncloaking the meningococcus: dynamics of carriage and disease. Lancet 1999; 353: 941–42. Maiden MCJ, Feavers IM. Population genetics and global epidemiology of the human pathogen Neisseria meningitidis. In: Baumberg S,Young JPW, Wellington EMH, Saunders JR, eds. Population genetics of bacteri a .C a m b ri d g e :C a m b ridge University P r e s s ,1 9 9 5 :2 6 9 – 9 3 . Vedros NA. Development of meningococcal serogroups. In:Vedros N A ,e d .E volution of meningococcal disease. Boca Rat o n ,F L :C R C Press Inc, 1987:33–37. Racoosin JA,Whitney CG, Conover CS, Diaz PS. Serogroup Y meningococcal disease in Chicago, 1991–1997. JAMA 1998; 280: 2094–98. Maiden MCJ, Bygraves JA, Feil E, et al. Multilocus sequence typing: a portable approach to the identification of clones within populations of pathogenic microorganisms. Proc Natl Acad Sci USA 1998; 95: 3140–45. Caugant DA ,K ristiansen BE, Froholm LO, Bovre K, Selander RK. Clonal diversity of Neisseria meningitidis from a population of asymptomatic carriers. Infect Immun 1988; 56: 2060–68. Wang J-F, Caugant DA, Morelli G, Koumaré B, Achtman M. Antigenic and epidemiological properties of the ET-37 complex of Neisseria meningitidis. J Infect Dis 1993; 167: 1320–29. Vogel U, Morelli G, Zurth K, et al. Necessity of molecular techniques to distinguish between Neisseria meningitidis strains isolated from patients with meningococcal disease and from their healthy contacts. J Clin Microbiol 1998; 36: 2465–70. Raymond NJ, Reeves M, Ajello G, et al. Molecular epidemiology of sporadic (endemic) serogroup C meningococcal disease. J Infect Dis 1997; 176: 1277–84. Takala AK, Santosham M, Almeido-Hill J, et al. Vaccination with Haemophilus influenzae type b meningococcal protein conjugate vaccine reduces oropharyngeal carriage of Haemophilus influenzae type b among American Indian children. Pediatr Infect Dis J 1993; 12: 593–99. Slack MP, Azzopardi HJ, Hargreaves RM, Ramsay ME. Enhanced surveillance of invasive Haemophilus influenzae disease in England, 1990 to 1996: impact of conjugate vaccines. Pediatr Infect Dis J 1998; 7: S204–07. Lipsitch M. Bacterial vaccines and serotype replacement: lessons from Haemophilus influenzae and prospects for Streptococcus pneumoniae. Emerg Infect Dis 1999; 5: 336–45. Gupta S, Galvani A. The effects of host heterogeneity on pathogen population structure. Philos Trans R Soc Lond B Biol Sci 1999; 354: 711–19. Kwara A, Adegbola RA, Corrah PT, et al. Meningitis caused by a serogroup W135 clone of the ET-37 complex of Neisseria meningitidis in West Africa. Trop Med Int Health 1998; 3: 742–46. Obaro SK, Adegbola RA, Banya WA ,G r e e n wood BM. Carriage of pneumococci after pneumococcal vaccination. Lancet 1996; 348: 271–72.
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Bright future for nuclear medicine See page 661 It was my good fortune to meet one of the founders of nuclear medicine, the late Glenn Seaborg, at the annual meeting of the Society of Nuclear Medicine in June,1996. He was keen as ever to discuss the future of nuclear medicine and was particularly interested in contacting the Commission on Nomenclature of Inorganic Chemistry, and not without reason. Glenn Seaborg was involved in the discovery of iron-59, iodine-131, cobalt-60, and technetium-99m. Element 106 is now named Seaborgium. In 1951, he, with Edwin McMillan, was awarded the Nobel Prize in chemistry. Several eminent scientists who applied the radioactive-tracer principle have also been Nobel laureates: Becquerel and the Curies (Physics, 1903); von Hevesy (Chemistry, 1943, for the first radiotracer study in animals); and Yalow (Medicine, 1977) for her work with Berson on the radioimmunoassay. Development in nuclear medicine has always been along two lines—clinical service, for diagnosis and therapy, and basic research, aimed at unravelling disease mechanisms, pathways of drug interaction, and early assessment of individual organ function. The large variation in practice worldwide reflects this duality and, naturally, the funding of the specialty. In the bigger medical institutions, large teams branch out into the different areas of application and research. In smaller centres, a simple but effective clinical service emerges. There is a world of difference between the complexity of a bone scan and tomographic maps of receptors, and between treatment of thyroid diseases with radioiodine and specific treatment of a lymphoma with a labelled, monoclonal antibody. The availability of nuclear medicine is hence non-uniform; some European countries do more than 50 000 procedures per million population whereas the frequency in others is about 10 000 per million. The attraction of nuclear medicine is strong. The detection of biological signals at the picomolar level, associated with specificity of the ligand in question, explains the interest and the potential. The methods are uniquely suited to tissue characterisation, to early assessment of the extent and severity of disease, and finally to treatment of disease with specific ligands. And yet over-regulation is posing possibly the biggest threat to its expansion. The estimation of risks involved is not proportional to the vast body of legislature that begins to impact on progress. The cost of registration of new radiopharmaceuticals is clearly deterring industry and sponsors alike. A tracer delivered once or twice to an individual in quantities of less than a milligram (often in the nano or picomolar range) will require, for registration purposes, the imprimatur of a body of legislation basically designed to monitor the side-effects of drugs, given commonly daily in doses of hundreds of milligrams. The series of six articles on nuclear medicine that The Lancet begins today describe the wide clinical applications, potential, and future developments. Nuclear medicine has offered new insights in the understanding of the dementias, the spread of cancer, and the early detection of coronary-artery disease. Not all potential applications could be covered in this series. There is, however, ample food for thought. Peter J Ell Institute of Nuclear Medicine,University College London Medical School, Mortimer Street,London W1N 8AA,UK
THE LANCET • Vol 354 • August 21, 1999