The impact of directly-observed treatment on the epidemiology of tuberculosis in Beijing.

Setting: Fully supervised chemotherapy, or directly observed treatment (DOT), for newly detected smear-positive cases in Beijing, has been successfully implemented for two decades.

Objective: To evaluate the progress made in tuberculosis control, and in particular to evaluate the impact of DOT on tuberculosis epidemiology in Beijing.

Design: Epidemiological parameters on tuberculosis, consisting of mortality, prevalence, notification rate, tuberculous meningitis in children and initial drug resistance rate, were collected and analysed.

Risk of tuberculosis infection and tuberculous meningitis after discontinuation of Bacillus Calmette-Guerin in Beijing.

In Beijing, the notification rate of smear-positive tuberculosis (TB) has been below 20 per 100,000 since 1986, and continues to decline. To accurately measure the risk of TB infection in a population in which the results of tuberculin skin testing were not confounded by vaccination with Bacillus Calmette-Guerin (BCG), BCG vaccination at birth was discontinued from 1988 in Shun-yi County. In 1995, the prevalence of TB infection among 12,836 primary school children aged 6 to 7 yr and without BCG scars was 1.

Tuberculosis control in Sudan against seemingly insurmountable odds.

Setting: Sudan, Africa's largest and one of its poorest countries, in which civil disturbance, resource limitation and communications difficulties are substantial impediments to delivery of health services.

Objectives: To 1) illustrate the burden of tuberculosis; 2) review measures taken to control the disease; 3) outline the introduction of the DOTS strategy; and 4) demonstrate the trend in the output of the DOTS strategy.

Methods: Published information on general health, tuberculosis and health structure provide the setting.

Classification of drug-resistant tuberculosis in an epidemic area.

Background: Traditionally, patients with drug-resistant tuberculosis are classified as having acquired drug-resistant or primary drug-resistant disease on the basis of a history of previous tuberculosis treatment. Only cases of primary drug resistance are assumed to be due to transmission of drug-resistant strains.

Methods: This descriptive study of 63 patients with drug-resistant tuberculosis assessed the relative contribution of transmission of drug-resistant strains in a high-incidence community of Cape Town, South Africa, by restriction-fragment length polymorphism (RFLP).

Affordability of inhaled corticosteroids as a potential barrier to treatment of asthma in some developing countries.

Setting: The cost and availability of the medications required for the treatment of asthma may represent potential barriers to effective management.

Method: A survey of prices and policies for components of asthma treatment in 1998, in Algeria, Burkina Faso, Ivory Coast, Guinea, Mali, Syria, Turkey and Vietnam.

Results: Medications were consistently available in only four of the eight countries studied.

Lung health in Alberta farmers.

Setting: A study conducted in the rural areas of two counties in east-central Alberta, Canada.

Objective: To investigate the relationship between lung health and dust exposure in farmers.

Design: A cross-sectional study of 781 farmers growing grain crops and raising livestock.

Exogenous reinfection as a cause of recurrent tuberculosis after curative treatment.

Background: For decades it has been assumed that postprimary tuberculosis is usually caused by reactivation of endogenous infection rather than by a new, exogenous infection.

Methods: We performed DNA fingerprinting with restriction-fragment-length polymorphism analysis on pairs of isolates of Mycobacterium tuberculosis from 16 compliant patients who had a relapse of pulmonary tuberculosis after curative treatment of postprimary tuberculosis. The patients lived in areas of South Africa where tuberculosis is endemic.

Cultural barriers to asthma management.

This article reviews published evidence which addresses the relevance of cultural factors in the delivery of health services for asthma patients. In addition, it suggests a framework within which further research could be carried out to advance our knowledge on this topic.

Epidemiology of respiratory infectious diseases.

Respiratory infections are a frequent burden to health despite the fact that cost-effective methods for their prevention and cure are available. Acute respiratory infections in children under 5 years of age are the most frequent cause of death from lung disease globally, causing more than 4 million deaths annually. Tuberculosis is the most frequent cause of death from a single pathogen in persons aged 15 to 49 years (a total of 2 million to 3 million deaths annually).

Screening for tuberculosis infection and disease.

Screening is a health-related activity which has clear indications and guidelines which must be followed when this activity is carried out. Methods for screening for tuberculosis infection and disease are available and have been evaluated. Most of the criteria for screening are relevant to tuberculosis.

[The epidemiology of tuberculosis and of the resistance to antitubercular agents].

Tuberculosis is once more a subject of world wide preoccupation; since 1985 a disturbing recrudescence of this disease has been noted in numerous countries related to population growth and the worsening of poverty in those countries without natural resources, and disadvantaged groups living on the margins of society in rich countries, along with the occurrence of an epidemic of HIV (VIH). In numerous developed countries where tuberculosis no longer represents a public health problem, the care services have little by little been closed or re-orientated and the principles of treatment of tuberculosis have been forgotten. The direct consequence of this has often been inadequate treatment and its corollary: the emergence of strains multiresistant to Isoniazid and Rifampicin.

Evaluation of a standardized recording tool for sputum smear microscopy for acid-fast bacilli under routine conditions in low income countries.

Setting: Laboratories performing sputum smear microscopy for tuberculosis in Benin, Malawi, Nicaragua and Senegal.

Methods: Analysis of computerized laboratory registers to ascertain workload, yield from serial smear examination, and demographic characteristics of examinees.

Results: Data from more than 60,000 examinees in 42 laboratories showed that the average number of smears examined per day ranged from 4 to 19 (mean 6) per country.

Successful management of a national tuberculosis programme under conditions of war.

Objective: To compare treatment results before and after introduction of short course tuberculosis chemotherapy and to identify factors affecting the results.

Design/setting: An eight-month chemotherapy regimen for smear-positive pulmonary tuberculosis was introduced in Nicaragua in 1984 with external financial assistance. We performed a retrospective record review to compare treatment results before and after introduction of short-course chemotherapy.

[Principles and organization of tuberculosis control].

Tuberculosis control must be organized by establishing programmes that are then implemented rigorously. The aim is to eradicate tuberculosis by applying a set of treatment procedures. These include, in particular, the detection of infectious cases in symptomatic patients who present to health services and their rapid treatment with chemotherapy, which makes them non-infectious and ensures their full recovery.

The yield of acid-fast bacilli from serial smears in routine microscopy laboratories in rural Tanzania.

Routine results of direct examination of sputum smears for acid-fast bacilli from 34 laboratories in Tanzania were analysed. These represented 8 regions providing 94 laboratory-years of work; 61,580 tuberculosis suspects were evaluated with the aid of 141,371 smears. The average proportion of cases found among suspects was 18.

A computer-based ordering system for supplies in national tuberculosis programs.

Setting: National tuberculosis programs in need of budgeting and planning for supplies.

Objective: To assist national managers to rationally and rapidly determine needs in supplies and their costs for the national tuberculosis program.

Methods: A spreadsheet has been developed to calculate needs in supplies for tuberculosis control based on the number of nationally notified cases.