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J F Broekmans

Publications and source records attributed to J F Broekmans.

10 recordsLinked to original sources
PubMed2000

Defaulting from tuberculosis treatment in The Netherlands: rates, risk factors and trend in the period 1993-1997.

The aim of this study was to assess the rate of defaulting from treatment among tuberculosis patients diagnosed in the Netherlands in the period 1993-1997, whether risk groups for defaulting can be identified at the start of treatment and the trend of defaulting over time. The Netherlands Tuberculosis Register provided data on all patients diagnosed in the Netherlands during the period 1993-1997. Defaulting probabilities were determined using Kaplan-Meier survival analysis and risk factors were identified with Cox's proportional hazard analysis. Of 7,529 patients with reported treatment outcome, 718 (10%) defaulted or left the country within 1 yr after starting treatment. Defaulting probabilities were 9% (95% confidence interval (CI) 8-10%) among 5,256 patients in low-risk groups, 17% (95% CI 14-19%) among 1,437 asylum seekers and 29% (95% CI 24-34%) among 836 patients in other high-risk groups (other recent immigrants, illegal immigrants, the homeless, prisoners and nationals from Eastern Europe). Defaulting probabilities decreased over time from 12% in 1993 to 7% in 1997. Risk groups for defaulting can be recognized at the start of treatment. The decreasing defaulting probabilities were probably due in part to shortening treatment from 9 to 6 months and improved follow-up of asylum seekers. However, additional measures are needed to reduce defaulting among the homeless, recent immigrants, illegal immigrants and prisoners.

Adult↗
PubMed2000

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 1.4%, 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.

BCG Vaccine↗
PubMed2000

The design of multi-stage tuberculin surveys: some suggestions for sampling.

SETTING: Tuberculin surveys of children to estimate national or regional infection prevalences are commonly designed as multi-stage surveys. These surveys require strategies for the efficient sampling of sub-units at each stage. OBJECTIVES: To develop guidelines for sampling in tuberculin surveys. DESIGN: Sampling theory was used to develop a simple and efficient sampling strategy for planning and analysing tuberculin surveys. The issue of sample sizes is considered. RESULTS: Formulae for the calculation of infection prevalences and their confidence intervals are developed. Sample sizes are discussed. CONCLUSION: We recommend that districts be sampled using sampling proportional to size, in which larger units have a larger probability of being included in the sample. Schools are sampled next using simple random sampling, where each school within a district has the same probability of being included in the sample. In each school all eligible children are Mantoux tested. The number of children tested per district should be approximately constant. Increasing the number of selected districts is usually more efficient for increasing the precision of the estimate than increasing the number of children per district beyond several hundred to a few thousand.

Bias↗
PubMed1999

Transmission of tuberculosis between people of different ages in The Netherlands: an analysis using DNA fingerprinting.

SETTING: In the period 1950 to 1980 the risk of tuberculous infection in the Netherlands declined more steeply than tuberculosis incidence. This study aimed at determining whether this might be explained by preferential transmission within age groups. METHODS: Using restriction fragment length polymorphism (RFLP) typing on all Mycobacterium tuberculosis isolates in the Netherlands from 1993 to 1996, clusters with identical fingerprints were identified. The correlation between the ages of people in clusters of two Dutch patients was determined. RESULTS: The mean difference in age between the two people, in 81 clusters of two, was 13.9 years, while the mean age difference between all possible pairs of individuals in this data set was 25.5 years. Fisher's intraclass correlation coefficient was 0.62 (95% confidence interval [CI] 0.46-0.74). CONCLUSION: It is concluded that sources of tuberculosis may preferentially transmit infection to people close to their own age. As the average age of cases has increased in the period 1950-1980, sources may have become less likely to infect children in whom the risk of infection has been measured. The annual risk of infection measured in children and young adults in countries with low levels of tuberculosis may not apply to older members of the population.

Adolescent↗
PubMed1991

The point of view of a low prevalence country: The Netherlands.

The elimination of tuberculosis in the Netherlands is not envisaged before 2025. The evidence presented in this paper suggests that the elimination phase asks for a revision of existing control strategies. In the Netherlands a new role is identified for a voluntary tuberculosis organisation like the Royal Netherlands Tuberculosis Association (KNCV) in the areas of expert consultation, surveillance, post-graduate education and consensus and protocol development. A major challenge for a low prevalence country is the existence of high prevalence countries; KNCV's contribution to the success of the Mutual Assistance Programme of the IUATLD in Tanzania, Malawi, Benin, Kenya and Mali is discussed. A major role is identified for the IUATLD and voluntary organisations like KNCV in WHO's new global programme against tuberculosis. The involvement of a Dutch voluntary organisation, the Medical Committee The Netherlands-Vietnam (MCNV) in support of the national tuberculosis programme in Vietnam illustrates this development.

Adolescent↗
PubMed1991

Tuberculosis and HIV-infection in developing countries.

Tuberculosis is a major public health problem in developing countries. In recent years, a (cost-)effective intervention has been developed in the national programmes of Tanzania and other developing countries. HIV transmission in populations with a high background prevalence of tuberculosis infection will increase the incidence of tuberculosis disease substantially. World Health Organization and World Bank are currently formulating new strategies to revitalise the global efforts against tuberculosis.

Adolescent↗