著者

橋本 達一郎

出版者

JAPANESE SOCIETY FOR TUBERCULOSIS

雑誌

結核 (ISSN:00229776)

巻号頁・発行日

vol.62, no.2, pp.51-60, 1987-02-15 (Released:2011-05-24)

参考文献数

35

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BCG vaccination against tuberculosis has been carried out for more than half century since the birth of BCG vaccine. The progress and problems of BCG vaccination in the world were briefly reviewed here in two aspects, protective effectiveness and complications, especially during recent 10 years.1. General status of BCG vaccination todayIn most countries, intradermal injection with freeze-dried BCG vaccine is being performed in young children, particularly new-borns and infants in developing countries. Percutaneous BCG vaccination, now being conducted in a few countries, has less complications but varied effectiveness. The BCG strain, dosage and viability of the vaccine have carefully been selected in each country, especially for young children, as these factors were found to be closely related to the effectiveness and complications of the BCG vaccination.2. Effectiveness of BCG vaccinationIt is surprising that the efficacy of BCG vaccination has extensively been disputed up to the present, because the most reliable controlled trials carried out since 1930, had shown very much disparate results of protective effectiveness from none to some 80 %. A well-designed large-scale controlled trial with the secured freeze-dried BCG vaccine was carried out recently in South Indian in order to verify the efficacy of BCG vaccination. However, the South Indian trial gave no protection against bacillary pulmonary tuberculosis in children and young adult throughout 15 years of follow up.Explanations and hypothesis have been proposed so far for the unexpected results of the South Indian trial, and vaccine dose (viability), infectious with atypical mycobacteria and weak pathogenicity of infectious tubercle bacilli in local area were taken up for the possible causes. Although until present any hypothesis has not yet been confirmed, it can be said that the BCG vaccination may not always be effective in some area of the world.As the South Indian trial gave no direct information on the efficacy of BCG vaccine in child hood type tuberculosis, a policy to continue BCG vaccinaion in young children was recommended. Also a number of the retrospective studies had shown the protective effect of BCG vaccine against childhood tuberculosis. However, the controlled BCG trial in infants was desired in the future and recently the case-control study in children was carried out to prove the efficacy of BCG vaccination in tuberculosis contacts.3. The complications of BCG vaccinationThe BCG vaccine should be highly effective with less complications. However, the stronger the BCG strain used the more the complications in terms of the suppurative lymphadenitis in young children, as shown in the comparison of vaccine strains between French and J apanese in the field study. As a result, the vaccine of stronger strain which may be more immunogenic, had to be adjusted in the dosage to expect acceptable complications.More serious complications such as disseminated BCG infectious had never been systematically determined on a world-wide scale. On behalf of IUAT, A. Lotte et al had the first time systematically calculated the incidence of serious complications of BCG vaccinaion on a world scale. The number of disseminated BCG infectious (non-fatal and fatal) and post-BCG diseases were disclosed in the comprehensive study. Although the incidence of the serious BCG complications was extremely low, this survey is very useful for decision of BCG vaccination policy in the future along with the protective effectiveness of BCG vaccination in the area.

著者

橋本 達一郎

出版者

一般社団法人 日本結核病学会

雑誌

結核 (ISSN:00229776)

巻号頁・発行日

vol.57, no.6, pp.329-334, 1982 (Released:2011-05-24)

参考文献数

52

著者

橋本 達一郎

出版者

一般社団法人 日本結核病学会

雑誌

結核 (ISSN:00229776)

巻号頁・発行日

vol.48, no.3, pp.51-59, 1973-03-15 (Released:2011-05-24)

参考文献数

91

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The tuberculin reaction, classical form of delayed type hypersensitivity, is defined as an immunologically determined inflammatory response characterized mainly by delayed onset of the reaction and by a mononuclear cell infiltration at the reaction site. These two characteristics are analysed in this review in relation to the mechanism of manifestation of the tuberculin skin reaction.Many evidences in the passive transfer of tuberculin sensitivity showed that the passive sensitization could be established without lag by injecting.intravenously the mononuclear cells from sensitized animals to normal in the absence of demonstrable serum antibody and that the immunologically competent cells would be sensitized lymphocyts transformed from thymus-dependent lymphocytes. After leaving the regional lymph nodes where they were produced, the sensitized cells start to circulate through the whole body to establish the over-all sensitization to tuberculin.Further experiments in which passive transfer was combined with desensitization or with labelling of donor or recipient demonstrated that the circulating sensitized cells interacted directly with the tuberculin injected intradermally and remained there at the contact site, reaching in several hours (within 6 hours) the necessary numbers for elicitation of the skin reaction. This immunologically specific process hardly manifests a visible reaction. The majority of the infiltrating cells at the reaction site consists of non-specific mononuclear cells, with a small portion of specifically sensitized cells, even when the reaction reaches the maximal intensity. The non-specific cells play a major role for the visible expression of the reaction, coming almost entirely from an actively dividing cell population through the blood stream. Thus the tuberculin reaction consists of 2 steps, specific and non-specific.

著者

橋本 達一郎

出版者

JAPANESE SOCIETY FOR TUBERCULOSIS

雑誌

結核 (ISSN:00229776)

巻号頁・発行日

vol.72, no.11, pp.629-637, 1997-11-15 (Released:2011-05-24)

参考文献数

11

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The BCG vaccines will celebrate the 100th anniversary of their discovery in a decade at the beginning of the next century since Albert Calmette and Camille Guebrin had presented it before the Academie des Sciences in 1908. At present tuberculosis kills more people than any other infectious disease about 3 million people a year, including almost 300, 000 children under 15, and is producing over 7, 000 deaths and over 24, 000 new cases every day. Therefore, WHO declared a global ealth emergency in 1993. More worse, recently multi-drug resistant tubercle bacilli are emerging rapidly making TB patients incurable.Under these situations we need a potent anti-tuberculosis vaccine. So first of all, we must check the century-old BCG before proceeding further.At moment, the BCG vaccines are being used worldwide in the largest quantities in the world, but still most controvercial vaccines anywhere.I would like to describe here their success and failure in the combat against the white plague.1. The Expanded Programme on Immunization (EPI).In 1974, when the EPI was launched by WHO, less than 5% of the world children were immunized against six infectious deseases including tuberculosis. In 1995 statistics, BCG gave the highest vaccination coverage, 87% higher than any other 5 vaccines of EPI for children. The BCG in EPI must have saved a lot of infants as the vaccine, has been proved to be most effective against the blood-born tuberculosis of child type.2. The efficacy of BCG vaccination against tuberculosis.Results of each 10 of randomized controlled trials (RCT) and Case-control studies (CCS) showed the protective efficacy against tuberculosis as uncertain, unpredictable, as protective efficacy varied from 80% to 0%.More recently, a Meta-analysis of selected papers on BCG field trials which were so far collected. They recalculated vaccine protective effect separately for pulmonary TB and for meningeal/miliary TB in the trials.As the result, it was found that protective effect against pulmonary TB could not be calculated, but protective effect against meningeal and miliary TB was calculated as 86%, 75% respectively, in RCT and CCS, being higher than against pulmonary TB.3. The duration of BCG efficacy against tuberculosis was confirmed to continue for 15 years after vaccination. The incidence of every form of tuberculosis decreased steeply during the 15 years following vaccination.4. BCG revaccination.A WHO statement was issued in 1995 mentioning that there is no definitive evidence that repeated BCG vaccination confers additional protection against tuberculosis.Therefore WHO has not recommended to repeat BCG vaccination because of no scientific evidence to support this practice. Multiple BCG revaccinations are not indicated in any persons.5. Complications with BCGSecond IUATLD study (1988) on complications induced by BCG was reviewed, especially following two points:1-2) Regional suppurative lymphadenitis3) Generalized lesions: fatal cases 1-2 Several Afirican regions had experienced that the risk of outbreak of suppurative BCG lymphadenitis was low for vaccines with Glaxo and Japanese strains, but much higher for vaccines with Pasteur. This experience in nineteen eighties has led EPI to replace the Pasteur BCG vaccine with less reactogenic BCG, Japanese or Glaxo BCG to solve the outbreak of suppurative adenitis complication.3 At moment, the only contra-indication of EPI BCG vaccination is symptomatic HIV infection (AIDS), but in the future asymptomatic HIV infection should be placed on alert, because fatal BCG generalized disseminations have already been experienced by HIV positive vaccinees although in a few cases in USA.