Recurrence of tuberculosis in a low-incidence setting.

Recurrence of active tuberculosis following treatment of an initial disease episode can occur due to endogenous re-activation or exogenous re-infection. Cases of recurrent tuberculosis in the Australian state of New South Wales between 1994 and 2006 were identified by data linkage analysis with confirmatory review of case notes. Patients with more than one culture-positive disease episode during that time period who had completed treatment for the initial disease episode were included. Genotyping of Mycobacterium tuberculosis was used to determine whether recurrence was likely to be due to re-activation or re-infection. There were 5,723 tuberculosis notifications between 1994 and 2006, 3,731 of which were culture-positive. Fifteen (0.4%) patients had recurrent culture-positive disease over a mean 5.7 yrs of follow-up (crude annual incidence 71 per 100,000 population). Recurrent tuberculosis was attributable to re-activation (indistinguishable strains) in 11 (73%) cases and to re-infection (different strains) in four (27%). In a low-incidence setting of tuberculosis, a control programme incorporating directly observed therapy for active disease resulted in a very low rate of recurrent tuberculosis over a long period of follow-up. Re-infection is less likely than re-activation, but still contributes significantly to the number of cases with recurrent disease.

Survival and degree of spread for female breast cancers in New South Wales from 1980 to 2003: implications for cancer control.

This study investigated associations of degree of spread at diagnosis of breast cancer and socio-demographic factors with the risk of death among NSW females diagnosed in 1980-2003. Trends by diagnostic period, socio-demographic differences, and the implications for cancer control were considered. NSW Central Cancer Registry data were analyzed using regression and rank-order tests to show predictors of death from breast cancer and trends in degree of spread. Compared with localized disease, case fatality was thrice and 14 times higher for cancers with regional spread and distant metastases, respectively. After adjusting for degree of spread and socio-demographic differences, the relative risk of death from breast cancer has declined in recent diagnostic periods compared with the 1980-1983 baseline, reaching a low of 0.38 (0.35, 0.40) for 1999-2003. Age-specific analyses indicated that relative risks were lower in 1999-2003 for 50-69 year olds (RR = 0.31) than younger (RR = 0.40), or older (RR = 0.46) females. Regional or distant disease at diagnosis was lowest in the older age groups, the highest socio-economic stratum and in more recent periods. Females born in non-English speaking countries presented with more advanced disease, as did metropolitan women with the highest access to health services. Degree of spread of cancer at diagnosis is a powerful predictor of case fatality. Case fatalities from breast cancer have declined by diagnostic period, after adjusting for degree of spread, which may reflect treatment and screening advances. Attention should be directed at reducing disparities by socio-economic status and encouraging migrant women to present earlier.

Pooling sputum samples to improve the feasibility of Xpert® MTB/RIF in systematic screening for tuberculosis.

SETTING: Systematic screening for tuberculosis (TB) using Xpert® MTB/RIF. OBJECTIVE: To determine whether pooling sputum samples for Xpert testing may improve the feasibility and cost-effectiveness of Xpert by reducing the number of Xpert tests required. DESIGN: Mycobacterium tuberculosis-spiked sputum samples at low organism concentrations were used to mimic samples that are more likely to be found in the screening, compared to the diagnostic, setting. Using Xpert, pooled sputum samples were tested from a pooling ratio of 1 in 2 to 1 in 12. RESULTS: A linear relationship between the pooling ratio and the Xpert MTB cycle threshold (Ct) value was found. As the sputum pooling ratio increased, the Ct value also increased. However, the slope of this increase was relatively small. In the majority of the samples pooled (75/96, 78.1%), Xpert was able to detect M. tuberculosis. CONCLUSION: These findings suggest that sputum pooling may be a viable method of improving the feasibility and cost-effectiveness of large-scale sputum testing using Xpert in the TB screening setting.

Cervical cancer mortality in Australia: contrasting risk by Aboriginality, age and rurality.

BACKGROUND: The poor health status of Australia's indigenous population is reflected in relatively high mortality rates from almost all causes, including preventable causes such as cervical cancer, where the rate is six to eight times that of non-Aboriginal women. However, there is little information on the geographical distribution of risk, an important issue for service deployment. This study examined the risk of death from cervical cancer in relation to Indigenous status, age and rurality. METHODS: Data from death registers from Australian states and territories who have identified Aboriginal people were examined for 1986-1997 to obtain a list of all deaths where the primary cause was cancer of the cervix. The data categorized females by 5-year age group, by metropolitan, rural or remote category and by Indigenous status. Mean age at death and standardized mortality ratios for deaths from cervical cancer were calculated for Aboriginal compared with non-Aboriginal women in metropolitan, rural and remote areas. RESULTS: The risk of death from cervical cancer for Aboriginal women compared with non-Aboriginal women increased by 4.3-fold for metropolitan areas, 9.7-fold for rural areas and 18.3-fold for remote areas. CONCLUSIONS: Aboriginal women in rural and remote areas of Australia are at significantly higher risk of death from cancer of the cervix than either Aboriginal women in metropolitan areas or non-Aboriginal women in any area. This result raises questions about access to services for prevention and early diagnosis and other factors that might impact on the incidence and natural history of the disease.

Mutations in rpoB gene and rifabutin susceptibility of multidrug-resistant Mycobacterium tuberculosis strains isolated in Australia.

Control of tuberculosis, the single largest killer among the infectious diseases, has been threatened by the emergence of multidrug-resistant Mycobacterium tuberculosis (MDRTB) infection due to the limited treatment options. Rifampicin (RIF) resistance is considered as a marker for MDRTB. The aim of this study was the detection of rpoB gene mutations and rifabutin resistance in MDRTB strains recently isolated in Australia by a line probe assay (INNO-LiPA Rif. TB, Innogenetics). Rifabutin and RIF susceptibility of 20 MDRTB and 16 RIF-sensitive M. tuberculosis complex clinical isolates were studied. The overall concordance of the line probe assay (LiPA) with phenotypic RIF susceptibility test was 96%. Seven distinct nucleotide substitutions were identified in 21 of 22 RIF-resistant isolates of diverse geographical origins, but in none of the RIF-sensitive strains. The majority (71%) of mutations occurred in the 526-533 codons and were associated with resistance to rifabutin and RIF. Of the RIF-resistant MDRTB strains, 18% appeared to be rifabutin-sensitive and produced delta S2 and delta S3 INNO-LiPA patterns. We conclude that amino acid substitutions at Asp516 and Ser522 in the rpoB gene in RIF-resistant M. tuberculosis predict rifabutin susceptibility for MDRTB. Use of the LiPA for RIF and rifabutin resistance may facilitate the rapid response required to limit the extent and severity of MDRTB transmission and infection.

Outbreak of extended spectrum beta lactamase producing Klebsiella pneumoniae in a neonatal unit.

An outbreak of extended spectrum beta lactamase producing Klebsiella pneumoniae (ESBLKp) in a neonatal unit was controlled using simple measures. Normally, the control of such infections can be time consuming and expensive. Seven cases of septicaemia resulted in two deaths. ESBLKp isolates were subtyped by pulsed field gel electrophoresis, and four of the five isolates typed were identical. Control of the outbreak was achieved by altered empiric antibiotic treatment for late onset sepsis and prevention of cross infection by strict attention to hand washing. Widespread colonisation of babies in the unit was presumed, so initial surveillance cultures were not performed. No further episodes of sepsis occurred.

Population-based cancer control: where is the greatest benefit from proven strategies to 'regain' years of life lost prematurely?

OBJECTIVE: To apply a 'health gain' approach to population-based cancer control. METHOD: We calculated the potential years of life otherwise lost prematurely which could be 'regained' through implementation of cancer control programs for which Level I or Level II evidence already exists for population outcomes. RESULTS: More potential years of life lost (PYLLs) would be 'regained' by enforcing a 'smoke-free' Australia than by any other possible scenario based on proven effectiveness. Even achievable scenarios for tobacco control (17% or 20% prevalence) would 'regain' more PYLL than either mammographic screening according to national policy or faecal occult blood testing (FOBT) of both men and women over 50 years for colorectal cancer. CONCLUSIONS: As few commentators remain optimistic that more money will be allocated to health, strategic thinking for health gain needs to re-appraise resource allocation for population-based cancer control in Australia. IMPLICATIONS: We recommend wider debate in response to our finding that, on the basis of best available evidence, the greatest potential for health gain lies less in cancer screening than fully funded tobacco control.

Mycobacterium ulcerans infections in two horses in south-eastern Australia.

Two horses were diagnosed as having Mycobacterium ulcerans infections. The first was a 21-year-old Quarterhorse-cross mare living in Mallacoota (a coastal town near the border of New South Wales and Victoria, Australia) that presented with lichenification, hair-loss and oedema on a fetlock, which subsequently ulcerated, as well as a non-healing ulcer on the wither. The second horse was a 32 year-old Standardbred gelding from Nicholson, near Bairnsdale, Victoria, that had an ulcerated lesion on its caudal thigh. Histologically, there were characteristic changes seen with M. ulcerans infections in other species, including extensive necrosis without associated granulomatous inflammation. The organisms were seen in Ziehl-Neelsen-stained smears or sections of the lesions from both horses and were isolated in culture from the first horse. A definitive diagnosis was provided by real-time polymerase chain reaction targeting the M. ulcerans-specific insertion sequence, IS2404. Delayed identification of the infectious agent in the first case led to the use of suboptimal antimicrobial therapy, resulting in failure to control the infection and the horse was subsequently euthanased. The second horse was successfully treated following surgical debulking of the centre of the lesion and one session of aggressive cryosurgery. Mycobacterium ulcerans should be considered in the differential diagnosis of unexplained lichenification with oedematous and ulcerated skin lesions in horses living in regions where this organism is endemic.

Life satisfaction and quality in Korean War veterans five decades after the war.

BACKGROUND: Military service is considered to be a hidden variable underlying current knowledge about well-being in the elderly. This study aimed to examine life satisfaction and quality of life in Australia's surviving male Korean War veterans and a community comparison group, and to investigate any association with war deployment-related factors. METHODS: Participants completed a postal questionnaire which included the Life Satisfaction Scale, the brief World Health Organization Quality of Life (WHOQOL-Bref) questionnaire and the Combat Exposure Scale. RESULTS: Korean War veterans reported significantly lower Percentage Life Satisfaction (PLS) and quality of life scores on four WHOQOL-Bref domains, compared with similarly aged Australian men (each p value <0.001). These outcomes were most strongly associated with severity of combat exposure and low rank. Mean PLS was approximately 15% lower in veterans who reported heavy combat compared with those reporting no combat, and approximately 12% lower in enlisted ranked veterans compared with officers. CONCLUSIONS: Fifty years after the Korean War, life satisfaction and quality in Australian veterans is poor relative to other Australian men, and is associated with deployment-related factors including combat severity and low rank. In order to respond effectively to current and projected population health needs, nations with large veteran populations may need to consider the impact of military service on well-being in later life.

Difficulties in detection and identification of Enterococcus faecium with low-level inducible resistance to vancomycin, during a hospital outbreak.

Between June and November 2004, a vancomycin-resistant Enterococcus faecium (VRE) strain was isolated from 13 patients in the haematology/bone marrow transplant unit. There were difficulties in identifying the organism, which had low-level, inducible vancomycin resistance, and standard screening methods did not reveal carriage in patients or their contacts. These technical failures led to spread of VRE and delays in providing appropriate management, which might otherwise have been avoided. Therefore, we reviewed our laboratory methods and compared three identification systems to determine which would best identify this VRE strain. The VITEK 2 (BioMerieux) correctly identified, as E. faecium, only two of 16 isolates, whereas API Rapid ID 32 Strep (BioMerieux) and Phoenix 100 (Becton Dickinson and Co.) correctly identified 13 of 15 and 12 of 13 isolates tested, respectively. Isolates from urine, tested by the CLSI disk diffusion method, were apparently susceptible or of intermediate susceptibility to vancomycin, upon primary testing. VITEK 2 and Phoenix 100 identified all isolates as vancomycin-resistant, although the MICs, measured by Etest, were in the susceptible range for three of 16 isolates. Reducing the vancomycin concentration in screening media substantially increased the sensitivity for detection of VRE. Isolates were characterized as genotype vanB2/3 by PCR and were indistinguishable from each other by pulsed-field gel electrophoresis. VRE with low-level inducible resistance can be missed by routine screening methods. Better identification and screening methods for detection of low-level vancomycin resistance are needed to improve surveillance and prevent transmission of VRE.

Sesame seed products contaminated with Salmonella: three outbreaks associated with tahini.

In November 2002, the first of three outbreaks of Salmonella Montevideo infection in Australia and New Zealand was identified in New South Wales, Australia. Affected persons were interviewed, and epidemiologically linked retail outlets inspected. Imported tahini was rapidly identified as the source of infection. The contaminated tahini was recalled and international alerts posted. A second outbreak was identified in Australia in June-July 2003 and another in New Zealand in August 2003. In a total of 68 S. Montevideo infections, 66 cases were contacted. Fifty-four (82%) reported consumption of sesame seed-based foods. Laboratory analyses demonstrated closely related PFGE patterns in the S. Montevideo isolates from human cases and sesame-based foods imported from two countries. On the basis of our investigations sesame-based products were sampled in other jurisdictions and three products in Canada and one in the United Kingdom were positive for Salmonella spp., demonstrating the value of international alerts when food products have a wide distribution and a long shelf life. A review of the controls for Salmonella spp. during the production of sesame-based products is recommended.

Invasive Haemophilus influenzae type b disease in elderly nursing home residents: two related cases.

We investigated two fatal cases of invasive Haemophilus influenzae type b (Hib) infection in a community nursing home in western Sydney, Australia. Two elderly women had lived in the same room, and the onset of their illness was 5 days apart. Hib isolates from blood cultures showed identical profiles by pulsed field gel electrophoresis. These findings suggest that Hib infection was transmitted within this nursing home. Serious Hib disease may be underrecognized in this setting. Continued surveillance and serotyping of invasive H. influenzae disease is essential for identifying groups at increasing risk that may benefit from immunization against Hib.

Cutaneous malignant melanoma in Australia, 1989.

OBJECTIVE: To describe the characteristics of cutaneous malignant melanoma in Australians in 1989. DESIGN AND DATA: Descriptive analysis of all invasive melanomas reported to State or Territory cancer registries in 1989. MAIN OUTCOME MEASURES: The age, sex and State or Territory of residence of affected individuals, and the topography, morphology and thickness of the melanoma. RESULTS: The age-standardised incidence rates of melanoma were 30.2 and 23.9 per 100,000 males and females respectively; the highest rates were observed for the male trunk (11.7 per 100,000) and female lower limbs (8.8 per 100,000); the most commonly specified morphology was superficial spreading melanoma, followed by nodular melanoma and lentigo malignant melanoma. Fifty-two per cent of melanomas of known thickness were thinner than 0.76 mm, with females having proportionally more thin melanomas than males, and males having twice the rate of melanomas thicker than 3 mm. Melanoma rates in northern latitudes were approximately double those further south. CONCLUSIONS: Distinct patterns of melanoma incidence by latitude and body site confirm the role of sunlight exposure in melanoma aetiology. Females often have thinner melanomas than males, which is reflected in their better prognosis. People living closer to the equator more often have level 1 (in situ) and thin invasive melanoma, probably related to increased awareness of melanoma risk with decreasing latitude. The collection of melanoma data would be improved if pathologists' reports routinely included melanoma site, morphology, level and thickness. All registries should collect data on level 1 melanomas to help evaluate early melanoma detection programs and to continue surveillance of the Australian skin cancer epidemic.