Search PubMed⌕ Search

Biomedical subjects

A Rouillon

Publications and source records attributed to A Rouillon.

5 recordsLinked to original sources
PubMed1976

Transmission of tubercle bacilli: The effects of chemotherapy.

The important differences in the infectivity of the various forms of tuberculosis can be explained by quantitative data concerning the behaviour of the tubercle bacillus in man and the number of bacilli in the lesions and sputum. Patients in whom tubercle bacilli can be detected by direct examination of the sputum smear are the main sources of transmission. Moreover the individuals infected by them break down more often with the disease. In the individual patient, the use of antibacterial drugs completely changes the natural history of the disease: not only do patients no longer die but they are cured; their period of infectivity is considerably reduced, relapses are avoided, chronicity disappears. The drugs used prophylactically in individuals of high risk groups prevent development of the disease. The impact of chemotherapy is reflected by a two-to-three-fold increase in the speed of decline of the risk of infection, a decline which had started before the introduction of the drugs. While patients given the right combination of drugs lose their infectivity in a few weeks (probably most often in less than two weeks), treatment must of course be continued much longer and regularly in order to ensure the maintenance of conversion and the absence of relapse. This stresses the importance of providing means to ensure the taking of the drugs by all patients. The future reduction of transmission will essentially depend on the maintenance of an adequate system ensuring the early diagnosis and correct treatment of cases, which will inevitably continue to appear among the already infected portion of the population. Epidemiological surveillance is mandatory as well as the surveillance of the delivery of services, particularly of the quality of diagnosis and therapeutic services. The roles of public health authorities and perhaps still more that of the practising physician, specialized and not specialized, remain considerable both from an epidemiological point of view and from the point of view of the relief of all the suffering still created by the disease.

Adolescent↗
PubMed1976

BCG vaccination and epidemiological situation: a decision making approach to the use of BCG.

The clinical efficacy of a well-controlled and correctly applied BCG vaccine can hardly be questioned, nor its usefulness under individual circumstances. But a problem more and more often raised now is that of the opportuneness, at the present time, to still use BCG on a mass- systematic - scale, particularly in the TB control programmes of low-prevalence countries. The article proposes an approach which, alongside with other methods already presented for assessing the epidemiological value of BCG and its public health indications, can help appreciate the advantages and disadvantages brought by vaccination in high- as well as in low-prevalence countries. The article focuses on the future, i.e. on what can, from now on, be expected from BCG in terms of epidemiological, economical and psychological benefits. Test runs were made considering three cohorts of 100,000 individuals (newborn, school enterers, school leavers), vaccinated or not vaccinated, submitted to various risks of infection (corresponding to conditions of high-, intermediate- and low-prevalence of tuberculosis) and experiencing various breakdown rates from infection to disease. Cost for BCG on the one hand, and cost for diagnosis, treatment of tuberculosis and loss of wages on the other, were also entered in the calculations; an attempt was also made to quantify in absolute terms and in relative ones the in conveniences linked to the application of BCG itself. Beyond figures and results presented as examples, what is more important is that the article furnished a method of reasoning and the possibility to feed one's own data in the model; it may help to encompass the scope and implications of a decision, and it furnishes elements of dialogue with other members of the planning team. It should be well realized that the elements provided and those which can be worked out are elements of reflexion to found a decision; the decision itself - to start, to pursue or to stop BCG on a mass scale - is of political nature (public health policy): it always implies a value judgement - from the part of the providers of the services and/or, preferably, from the part of the users, i.e. a preference which is the result of a 'weighing' between advantages and inevitable disadvantages, both involving time, place, existing system, existing beliefs and other fields of health and welfare.

Adolescent↗