The contribution of travellers visiting friends and relatives to notified infectious diseases in Australia: state-based enhanced surveillance.

Immigrants and their children who return to their country of origin to visit friends and relatives (VFR) are at increased risk of acquiring infectious diseases compared to other travellers. VFR travel is an important disease control issue, as one quarter of Australia's population are foreign-born and one quarter of departing Australian international travellers are visiting friends and relatives. We conducted a 1-year prospective enhanced surveillance study in New South Wales and Victoria, Australia to determine the contribution of VFR travel to notifiable diseases associated with travel, including typhoid, paratyphoid, measles, hepatitis A, hepatitis E, malaria and chikungunya. Additional data on characteristics of international travel were collected. Recent international travel was reported by 180/222 (81%) enhanced surveillance cases, including all malaria, chikungunya and paratyphoid cases. The majority of cases who acquired infections during travel were immigrant Australians (96, 53%) or their Australian-born children (43, 24%). VFR travel was reported by 117 (65%) travel-associated cases, highest for typhoid (31/32, 97%). Cases of children (aged <18 years) (86%) were more frequently VFR travellers compared to adult travellers (57%, P < 0·001). VFR travel is an important contributor to imported disease in Australia. Communicable disease control strategies targeting these travellers, such as targeted health promotion, are likely to impact importation of these travel-related infections.

Evaluation of a structured expert elicitation estimating the proportion of illness acquired by foodborne transmission for nine enteric pathogens in Australia.

Estimates of the proportion of illness transmitted by food for different enteric pathogens are essential for foodborne burden-of-disease studies. Owing to insufficient scientific data, a formal synthesis of expert opinion, an expert elicitation, is commonly used to produce such estimates. Eleven experts participated in an elicitation to estimate the proportion of illnesses due to food in Australia for nine pathogens over three rounds: first, based on their own knowledge alone; second, after being provided with systematic reviews of the literature and Australian data; and finally, at a workshop where experts reflected on the evidence. Estimates changed significantly across the three rounds (P = 0·002) as measured by analysis of variance. Following the workshop in round 3, estimates showed smoother distributions with significantly less variation for several pathogens. When estimates were combined to provide combined distributions for each pathogen, the width of these combined distributions reflected experts' perceptions of the availability of evidence, with narrower intervals for pathogens for which evidence was judged to be strongest. Our findings show that the choice of expert elicitation process can significantly influence final estimates. Our structured process - and the workshop in particular - produced robust estimates and distributions appropriate for inclusion in burden-of-disease studies.

A multi-state outbreak of Salmonella Saintpaul in Australia associated with cantaloupe consumption.

A multi-state outbreak of Salmonella enterica serovar Saintpaul infection occurred in Australia during October 2006. A case-control study conducted in three affected jurisdictions, New South Wales, Victoria and Australian Capital Territory, included 36 cases with the outbreak-specific strain of S. Saintpaul identified by multiple locus variable-number tandem repeat analysis (MLVA) in a faecal specimen and 106 controls. Consumption of cantaloupe (rockmelon) was strongly associated with illness (adjusted OR 23.9 95%, 95% CI 5.1-112.4). S. Saintpaul, with the outbreak MLVA profile, was detected on the skin of two cantaloupes obtained from an implicated retailer. Trace-back investigations did not identify the specific source of the outbreak strain of S. Saintpaul, but multiple Salmonella spp. were detected in environmental samples from farms and packing plants investigated during the trace-back operation. Cantaloupe production and processing practices pose a potential public health threat requiring regulatory and community educational interventions.

Estimating the risk of blood donation associated with HIV risk behaviours.

A blood donor questionnaire and declaration, with deferral of potential donors at a higher risk of blood-borne infections, was introduced in Australia in the mid-1980s to reduce the risk of donation of HIV-infected blood. However, the absolute risk of HIV transmission through blood donation from high-HIV-risk donors has not been estimated. This study presents a new method of assessing the risk posed to the blood supply by selected HIV risk behaviours. A model was developed to estimate the probability of blood donation during the window period for HIV infection. Five scenarios for blood donors were considered: (1) men who have sex with men (MSM), (2) men who have sex with women in Australia, (3) women who have sex with partners from countries with a high HIV prevalence, (4) men who have sex with commercial sex workers in Australia and (5) people injecting drugs used once in a year. Those estimated to be at highest risk of becoming infected and donating in the window period were MSM. Women who have sex with men from countries of high HIV prevalence are at greater risk than men who have sex with female sex workers from Australia. These three groups under current Australian guidelines are deferred from donating blood for 12 months. In Australia, a single episode of injecting drug use is associated with very low risk of HIV transmission. The model presented in this study can be used to assess the impact of selected individual risk behaviours on the safety of the blood supply.

Blunt chest trauma.

Blunt chest trauma represents a challenge to both nurses and physicians due to the frequent absence of clinical signs. When evaluating or predicting blunt chest trauma several components are important to remember.

Acute myocardial infarction.

Current statistics reflect that cardiovascular disease (CVD) continues to be the greatest health problem affecting the Australian population, accounting for approximately 42% of all deaths recorded. Of all cardiovascular disorders, ischaemic heart disease is associated with highest mortality rates.

Entropy-based reliability analysis for intelligent machines.

A new metric for performance assessment of intelligent machines has been developed. The method fuses concepts from the Theory of Intelligent Machines proposed by Saridis (1988) with traditional reliability analysis in the development of a measure which reflects both the uncertainty inherent in the intelligent machine and the uncertainty allowed by the task description. The metric is entropy based, and is shown to be analogous to a measure of system reliability.

A comment on thyrotropin measurement and evaluation.

There is a need for improvement of thyrotropin measurements in the clinical laboratory, specifically in the lower portion of the normal range. We cite realistic examples of incorrect, misleading data generated with many thyrotropin kits currently in use and propose a practical laboratory protocol to evaluate the performance of a procedure for determining thyrotropin. The protocol integrates medical physiology with analytical measurement.

Quantitative determination of hexylresorcinol in commercial antiseptic solution by high-pressure liquid chromatography.

High-pressure liquid chromatography was used with a 5-micron silica gel column to quantitate hexylresorcinol in a commercial antiseptic solution following extraction with methylene chloride. This method shows linearity to at least 0.025% hexylresorcinol. A mobile phase consisting of 63% heptane, 34% chloroform, and 5% methanol was used with a UV detector (254 nm) and a flow of 3 ml/min. No interfering substances were observed.

High-pressure liquid chromatographic determination of camphor and parachlorophenol in camphorated parachlorophenol.

Quantitative analyses of both camphor and parachlorophenol in camphorated parachlorophenol by high-pressure liquid chromatography is described. A 5% solution of phenol in the mobile phase (heptane-chloroform 3:2) served as the internal standard; the assay involved addition of this phenol solution to the camphorated parachlorophenol, followed by further dilution using the mobile phase (heptane-chloroform, 3:2) and injection into the instrument.

Quantitative determination of phenol by high-pressure liquid chromatography.

High-pressure liquid chromatography was used with a 5-micrometer silica gel column to quantitate the phenol in phenolated calamine lotion USP and a commercial antiseptic solution. This method requires less than 10 min/assay, and other compounds present in the products analyzed did not interfere.

Quantitative structure-activity relationships for 5-substituted 8-hydroxyquinolines as inhibitors of dental plaque.

Fourteen 8-hydroxyquinolines were tested for antiplaque activity by measuring their minimum inhibitory concentrations [MIC (M)] against Streptococcus mutans No. 6715. Linear regression analysis was conducted with the MIC (M) values and hydrophobic (log P), electronic (beta, pKaOH, pKaN), and steric [molar refractivity (MR), molecular weight (mol wt)] parameters. The best correlation (r2 = 0.90) was obtained with MR, log P, and beta. The smaller the steric contribution of the 5-substituent, the more active the compound. The parent 8-hydroxyquinoline was the most active. The negative contribution toward activity by 5-substituents larger than hydrogen can be overcome by the positive contributions of groups that are lipophilic and electron withdrawing; for example, the 5-chloro derivative is as active as the parent 8-hydroxyquinolines.