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Setting: Six provinces in Vietnam where the DOTS strategy was introduced in 1989., Objective: To assess the impact of improved tuberculosis (TB) control on TB epidemiology in Vietnam., Methods: Data from the surveillance system in the period 1990-2003 were analysed to assess trends of notification rates and the mean ages of notified cases. Data from repeated tuberculin surveys in the period 1986-2002 were estimated to assess the prevalence of TB infection, the annual risk of infection and its trend using various cut-off points in those with and without bacille Calmette-Guérin (BCG) scar., Results: Age-standardised notification rates in the period 1996-2003 declined significantly, by 2.6% to 5.9% per year, in five provinces. However, in four provinces notification rates in the age group 15-24 years increased significantly, by 4.5% to 13.6% per year, during this period. The mean age of newly diagnosed patients with smear-positive TB increased up to 1995 but decreased thereafter. The annual risk of TB infection showed a significant annual decrease (4.9% per year) in one province in surveys performed between 1986 and 1997, and in two provinces (6.6% and 4.7%) in surveys conducted between 1993 and 2002., Conclusion: These data suggest limited impact to date of the DOTS strategy in Vietnam.

Objective: To assess the yield of sputum smear microscopy and sex differences in the National Tuberculosis Control Programme in the north of Vietnam., Methods: Review of registers of 30 randomly selected laboratories (26 district, 4 provincial level)., Results: The average daily workload per technician was 4.4 examinations in district and 5.3 examinations in provincial laboratories. To find one smear-positive case, 9.7 suspects were examined and 29.3 smears done. The smear-positive rate (mean 10.3%) was higher among men (11.6%) than among women (8.4%, P < 0.001). There were more men than women among tuberculosis (TB) suspects (male:female ratio 1.36, 95%CI 1.19-1.54), but even more so among smear-positive patients (1.89, 95%CI 1.64-2.14), irrespective of specimen quality and number of smears examined. Three smears were examined for 18,055 suspects (61.7%). The incremental gain was 33.5% and 4.9% for the second and third smear examination, respectively; 186 (95%CI 160-221) smears needed to be examined to find one additional case of TB with a third serial examination., Conclusion: The diagnostic process seemed generally efficient. The male:female ratios suggest higher TB incidence in men rather than lower access to TB facilities for women. The third smear examination could be omitted.

Infectious multiresistant pulmonary tuberculosis was diagnosed in a 24-year-old woman from an Eastern European country who resided in the Netherlands illegally. Her chest X-ray showed extensive cavitating lesions in both lungs. The patient was infectious for a long time and contact investigation revealed 2 other cases of multiresistant tuberculosis, her boyfriend aged 39 and his father, aged 58 years. Transmission from the index case was confirmed by DNA fingerprinting. Seven contacts had a latent tuberculosis infection. All 3 tuberculosis patients were successfully treated, while a number of the infected contacts received preventive treatment. Multiresistant tuberculosis is on the rise in Eastern Europe. It is a serious disease with a high mortality rate despite treatment and has considerable social implications. This outbreak emphasises the necessity of maintaining an efficient tuberculosis control network in low incidence countries, such as the Netherlands. This is the first time an outbreak of multiresistant tuberculosis of this magnitude is described in the Netherlands.

Objective: To determine whether elimination of tuberculosis in the Dutch population can be achieved by the year 2030, taking into account the impact of immigration., Methods: The incidence of tuberculosis (all forms) in the period 1970 to 2030 was estimated using a life-table model for the Dutch population without the impact of immigration. The influence of immigration on tuberculosis incidence among the Dutch was modelled using four immigrant scenarios, distinguished by the assumed contact rate between immigrants and the Dutch population, and by different projections (middle, upper) of the future size of the immigrant population in The Netherlands., Results: The incidence of smear-positive tuberculosis among the Dutch is projected to be 1.4 per million in the scenario without the influence of immigrant cases, and ranging from 3.8 to 11.8 per million in the four immigrant scenarios. In all immigrant scenarios, the prevalence of tuberculosis infection will continue to decline and be less than 1% by the year 2030. At least 60% of Dutch tuberculosis cases in the year 2030 are expected to be the result of transmission from a foreign source case., Conclusion: Using a prevalence of tuberculosis infection of less than 1% as the elimination criterion, tuberculosis will probably be eliminated from the indigenous Dutch population by 2030. However, the incidence of smear-positive tuberculosis is expected to remain higher than 1 per million, and the majority of new tuberculosis cases among the Dutch may be attributable to recent infection from a foreign source case.

Tuberculosis is among the top ten causes of global mortality and affects low-income countries in particular. This paper examines, through a literature review, the impact of tuberculosis control measures on tuberculosis mortality and transmission, and constraints to scaling-up. It also provides estimates of the effectiveness of various interventions using a model proposed by Styblo. It concludes that treatment of smear-positive tuberculosis using the WHO directly observed treatment, short-course (DOTS) strategy has by far the highest impact. While BCG immunization reduces childhood tuberculosis mortality, its impact on tuberculosis transmission is probably minimal. Under specific conditions, an additional impact on mortality and transmission can be expected through treatment of smear-negative cases, intensification of case-finding for smear-positive tuberculosis, and preventive therapy among individuals with dual tuberculosis-HIV infection. Of these interventions, DOTS is the most cost-effective at around US$ 5-40 per disability-adjusted life year (DALY) gained. The cost for BCG immunization is likely to be under US$ 50 per DALY gained. Treatment of smear-negative patients has a cost per DALY gained of up to US$ 100 in low-income countries, and up to US$ 400 in middle-income settings. Other interventions, such as preventive therapy for HIV-positive individuals, appear to be less cost-effective. The major constraint to scaling up DOTS is lack of political commitment, resulting in shortages of funding and human resources for tuberculosis control. However, in recent years there have been encouraging signs of increasing political commitment. Other constraints are related to involvement of the private sector, health sector reform, management capacity of tuberculosis programmes, treatment delivery, and drug supply. Global tuberculosis control could benefit strongly from technical innovation, including the development of a vaccine giving good protection against smear-positive pulmonary tuberculosis in adults; simpler and shorter drug regimens for treatment of tuberculosis disease and infection; and improved diagnostics for tuberculosis infection and disease.

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 1.4%, giving an estimated annual risk of infection of 0.19% (95% confidence interval: 0.16 to 0.22%). The prevalence of TB infection in children aged 5 to 9 yr in Beijing in 1950 was 46%. The number of cases of tuberculous meningitis did not increase after discontinuation of BCG. We conclude that discontinuation of BCG had no detectable harmful effects, and that control of TB in Beijing has markedly reduced the prevalence of TB infection since 1950.