NSW Public Health Bulletin最新文献

A recently conducted study on tuberculosis contact investigations in six Sydney tuberculosis clinics - that together managed 59% of all tuberculosis cases in NSW from January 2000 to December 2009 - found that the prevalence of tuberculosis among contacts was comparable to other low-incidence settings. However, only 9% of contacts with latent tuberculosis infection received treatment. This paper explores the results of the study, evaluating potential missed opportunities to prevent tuberculosis among contacts, and discussing the mechanisms in decision making about treatment of latent tuberculosis infection. In particular, the paper focuses on the challenges of tuberculin skin test interpretation among contacts who have received Bacille Calmette-Guérin vaccination and who were born in countries where tuberculosis is endemic.

In Australia, tuberculosis notification rates have plateaued at a low level and disease is highly concentrated in immigrant communities where children may be affected. Many clinicians regard tuberculosis as an adult disease, hence it is rarely considered in the differential diagnosis of sick children. This paper provides a brief overview of the natural history of the disease in children to demonstrate the importance of taking a careful tuberculosis exposure history. It also provides guidance regarding the diagnosis, treatment and prevention of tuberculosis in children. The management of paediatric cases is not difficult if important differences with adult disease are carefully considered; these differences are discussed in detail.

Twenty-one percent of the world's tuberculosis cases are found in the Western Pacific Region. The region has demonstrated a lower rate of decline in incidence than the regions of Africa, the Americas and Europe. Issues around drug resistance, human immunodeficiency virus and diabetes impact on the burden of tuberculosis disease in the Western Pacific Region. Australia has exhibited a low and relatively stable tuberculosis incidence rate but has not progressed toward the desired international goal for tuberculosis elimination (<1 case per million population). The pathogenesis and transmission of tuberculosis make it difficult to achieve elimination within a geographically defined area. These aspects of disease control are amplified by globalisation and Australia's increasing economic and strategic engagement within the Western Pacific Region and South-East Asia. Promoting and supporting tuberculosis control within the Western Pacific Region provides an opportunity for Australia to maintain its low tuberculosis incidence rate and progress toward elimination.

This report describes the ongoing transmission of tuberculosis in Aboriginal communities in NSW. From October 2000 to July 2012 there were 30 linked cases of tuberculosis diagnosed in Aboriginal people - 22 in the North Coast area of NSW, with a further three cases in Sydney and five in southern Queensland. It is likely that a range of factors have contributed to this ongoing transmission, including delayed diagnosis, the extensive social connections within the communities affected, and the highly mobile living arrangements of many of those affected. Cases have continued to emerge despite implementation of tuberculosis control measures in line with state and international protocols. Tuberculosis control staff are working in partnership with Aboriginal communities to identify and implement appropriate tuberculosis control strategies.

Molecular strain typing of Mycobacterium tuberculosis has been possible for only about 20 years; it has significantly improved our understanding of the evolution and epidemiology of Mycobacterium tuberculosis and tuberculosis disease. Mycobacterial interspersed repetitive unit typing, based on 24 variable number tandem repeat unit loci, is highly discriminatory, relatively easy to perform and interpret and is currently the most widely used molecular typing system for tuberculosis surveillance. Nevertheless, clusters identified by mycobacterial interspersed repetitive unit typing sometimes cannot be confirmed or adequately defined by contact tracing and additional methods are needed. Recently, whole genome sequencing has been used to identify single nucleotide polymorphisms and other mutations, between genotypically indistinguishable isolates from the same cluster, to more accurately trace transmission pathways. Rapidly increasing speed and quality and reduced costs will soon make large scale whole genome sequencing feasible, combined with the use of sophisticated bioinformatics tools, for epidemiological surveillance of tuberculosis.