Search

The planning and delivery of care systems require knowledge on the ways in which individuals access available services that are funded by a range of health and community services. The aims of this study were to identify distinct groups of Home and Community Care (HACC) clients in New South Wales, Australia, based on patterns of actual service use, and to understand the health and social needs and resources of client groups that access different mixes of services. Multiple data sets linked at the individual level - including the 45 and Up Study community survey, the HACC Minimum Data Set and the Admitted Patient Data Collection for hospitals - provide an innovative basis to investigate the complexity of access to service use. Data were collected between 2006 and 2008. A cluster analysis based on clients' type and volume of community service use was conducted on the 4890 HACC clients in the linked dataset and nine distinct clusters of clients were identified. Three of these clusters were considered 'complex', in terms of the range of community and hospital assistance received, while the others comprised mainly of one or two dominant service types. The analytical approach and findings developed here provide a client-centred approach to monitor and evaluate access to local service systems that are being reformed to better integrate the delivery of health and community services currently funded and managed separately by national and state governments., (© 2011 Blackwell Publishing Ltd.)

Physical activity is an important factor in healthy aging and has been shown to reduce depressive symptoms. This association, however, is relatively understudied in older men. This study was a cross-sectional analysis of the association between physical activity (Active Australia Survey) and psychological distress (Kessler-10). Participants were a sample of 17,689 men age ≥ 65 yr drawn from a large-scale Australian cohort study of people age 45 years and over (The 45 and Up Study). The likelihood of reporting high or very high levels of psychological distress decreased with increasing weekly sessions of physical activity. Compared with participants reporting no sessions of physical activity, the fully adjusted odds ratio for high or very high psychological distress was .66 (95% CI .51-.85) for men who undertook 1-6 sessions of physical activity per week and decreased to .57 (95% CI, .43-.79) for men who reported 16 or more weekly sessions. The cross-sectional findings show that older men who are more active are less likely to report psychological distress, regardless of their level of functional limitation. Further research, informed by these findings, is required to investigate causal pathways and the temporal sequence of events.

Objective: To assess the relationship between obesity and sedentary behaviours, such as watching television or using a computer ('screen-time'), and describe how this relationship varies between population subgroups., Design: Cross-sectional analysis of the relationship between obesity (BMI ≥ 30 kg/m2) and screen-time, adjusted for age, sex, income and education and compared according to a range of personal characteristics., Setting: New South Wales, Australia., Subjects: A total of 91 266 men and women aged 45 years and above from the general population of New South Wales in 2006-2007 and providing self-reported information on height and weight and other factors., Results: Obesity prevalence was 21.4 %. Compared to individuals with <2 h of daily screen-time, the adjusted relative risks (RR) of obesity were 1.35 (95 % CI 1.26, 1.44), 1.70 (95 % CI 1.59, 1.82), 1.94 (95 % CI 1.81, 2.08) and 1.92 (95 % CI 1.80, 2.06) for 2-3, 4-5, 6-7 and ≥8 h, respectively. The increase in obesity with increasing screen-time was similar within categories of overall physical activity, but was attenuated in those in full-time paid work, compared to non-workers (P for interaction < 0.0001). Among non-workers, the overall obesity RR per 2 h increase in daily screen-time was 1.23 (95 % CI 1.21, 1.25) and was significantly elevated in all groups examined, ranging from 1.16 to 1.31 according to sex, level of age, education, income, smoking and fruit consumption. The RR did not differ significantly according to overall physical activity, region of residence and alcohol and vegetable consumption, but was substantially lower in disabled v. not-disabled individuals (P for interaction < 0.0001)., Conclusions: Obesity increases with increasing screen-time, independent of purposeful physical activity. This was observed in all population groups examined, although it is attenuated in full-time workers and disabled individuals.

Background: Better communication is often suggested as fundamental to increasing the use of research evidence in policy, but little is known about how researchers and policy makers work together or about barriers to exchange. This study explored the views and practice of policy makers and researchers regarding the use of evidence in policy, including: (i) current use of research to inform policy; (ii) dissemination of and access to research findings for policy; (iii) communication and exchange between researchers and policy makers; and (iv) incentives for increasing the use of research in policy., Methods: Separate but similar interview schedules were developed for policy makers and researchers. Senior policy makers from NSW Health and senior researchers from public health and health service research groups in NSW were invited to participate. Consenting participants were interviewed by an independent research company., Results: Thirty eight policy makers (79% response rate) and 41 researchers (82% response rate) completed interviews. Policy makers reported rarely using research to inform policy agendas or to evaluate the impact of policy; research was used more commonly to inform policy content. Most researchers reported that their research had informed local policy, mainly by increasing awareness of an issue. Policy makers reported difficulty in accessing useful research syntheses, and only a third of researchers reported developing targeted strategies to inform policy makers of their findings. Both policy makers and researchers wanted more exchange and saw this as important for increasing the use of research evidence in policy; however, both groups reported a high level of involvement by policy makers in research., Conclusion: Policy makers and researchers recognise the potential of research to contribute to policy and are making significant attempts to integrate research into the policy process. These findings suggest four strategies to assist in increasing the use of research in policy: making research findings more accessible to policy makers; increasing opportunities for interaction between policy makers and researchers; addressing structural barriers such as research receptivity in policy agencies and a lack of incentives for academics to link with policy; and increasing the relevance of research to policy.

Objective: To determine the perceived threat of terrorist attack in Australia and preparedness to comply with public safety directives., Methods: A representative sample of 2,081 adults completed terrorism perception questions as part of the New South Wales Population Health Survey., Results: Overall, 30.3% thought a terrorist attack in Australia was highly likely, 42.5% were concerned that self or family would be directly affected and 26.4% had changed the way they lived due to potential terrorist attacks. Respondents who spoke a language other than English at home were 2.47 times (Odds Ratios (OR=2.47, 95% CI:1.58-3.64, p<0.001) more likely to be concerned self or family would be affected and 2.88 times (OR=2.88, 95% CI:1.95-4.25, p<0.001) more likely to have changed the way they lived due to the possibility of terrorism. Those with high psychological distress perceived higher terrorism likelihood and greater concern that self or family would be directly affected (OR=1.84, 95% CI:1.05-3.22, p=0.034). Evacuation willingness was high overall but those with poor self-rated health were significantly less willing to leave their homes during a terrorism emergency., Conclusion: Despite not having experienced recent terrorism within Australia, perceived likelihood of an attack was higher than in comparable western countries. Marginalisation of migrant groups associated with perceived terrorism threat may be evident in the current findings., Implications: This baseline data will be useful to monitor changes in population perceptions over time and determine the impact of education and other preparedness initiatives.

Background: At present, we have very limited ability to compare public health activity across jurisdictions and countries, or even to ascertain differences in what is considered to be a public health activity. Existing standardised health classifications do not capture important dimensions of public health, which include its functions, the methods and interventions used to achieve these, the health issues and determinants of health that public health activities address, the resources and infrastructure they use, and the settings in which they occur. A classification that describes these dimensions will promote consistency in collecting and reporting information about public health programs, expenditure, workforce and performance. This paper describes the development of an initial version of such a classification., Methods: We used open-source Protégé software and published procedures to construct an ontology of public health, which forms the basis of the classification. We reviewed existing definitions of public health, descriptions of public health functions and classifications to develop the scope, domain, and multidimensional class structure of the ontology. These were then refined through a series of consultations with public health experts from across Australia, culminating in an initial classification framework., Results: The public health classification consists of six top-level classes: public health 'Functions'; 'Health Issues'; 'Determinants of Health'; 'Settings'; 'Methods' of intervention; and 'Resources and Infrastructure'. Existing classifications (such as the international classifications of diseases, disability and functioning and external causes of injuries) can be used to further classify large parts of the classes 'Health Issues', 'Settings' and 'Resources and Infrastructure', while new subclass structures are proposed for the classes of public health 'Functions', 'Determinants of Health' and 'Interventions'., Conclusion: The public health classification captures the important dimensions of public health activity. It will facilitate the organisation of information so that it can be used to address questions relating to any of these dimensions, either singly or in combination. The authors encourage readers to use the classification, and to suggest improvements.

Background: To help improve incident preparedness this study assessed socio-demographic and socio-economic predictors of perceived risk of terrorism within Australia and willingness to comply with public safety directives during such incidents., Methods: The terrorism perception question module was incorporated into the New South Wales Population Health Survey and was completed by a representative sample of 2,081 respondents in early 2007. Responses were weighted against the New South Wales population., Results: Multivariate analyses indicated that those with no formal educational qualifications were significantly more likely (OR = 2.10, 95%CI:1.32-3.35, p < 0.001) to think that a terrorist attack is very or extremely likely to occur in Australia and also more likely (OR = 3.62, 95%CI:2.25-5.83, p < 0.001) to be very or extremely concerned that they or a family member would be directly affected, compared to those with a university-level qualification. Speaking a language other than English at home predicted high concern (very/extremely) that self or family would be directly affected (OR = 3.02, 95%CI:2.02-4.53, p < 0.001) and was the strongest predictor of having made associated changes in living (OR = 3.27, 95%CI:2.17-4.93, p < 0.001). Being female predicted willingness to evacuate from public facilities. Speaking a language other than English at home predicted low willingness to evacuate., Conclusion: Low education level is a risk factor for high terrorism risk perception and concerns regarding potential impacts. The pattern of concern and response among those of migrant background may reflect secondary social impacts associated with heightened community threat, rather than the direct threat of terrorism itself. These findings highlight the need for terrorism risk communication and related strategies to address the specific concerns of these sub-groups as a critical underpinning of population-level preparedness.

This research assessed factors associated with willingness to comply with vaccination, isolation, and face mask wearing during an anticipated influenza pandemic. Data were collected from 2081 adults (16+) using a module of questions incorporated into the NSW Health Adult Population Health Survey. High levels of willingness to comply were reported with 73% either very or extremely willing to receive vaccination, 67% willing to isolate themselves, 58% willing to wear a face mask, and 48% willing to comply with all three behaviors. Further analysis indicated concern for self and family and higher levels of education were associated with high levels of willingness to comply. Younger people (16-24) were the least willing to comply; especially with wearing a face mask. Those with children reported higher levels of willingness to receive vaccination, and respondents who speak a language other than English at home were less willing to isolate themselves or comply with all behaviors. These findings provide a baseline measure of anticipated public compliance with key public health behaviors in the event of an influenza pandemic in the Australian population, and help to identify groups that may be more resistant to individual measures and may require additional attention in terms of risk communication strategies or health education.

Background: Baseline data is necessary for monitoring how a population perceives the threat of pandemic influenza, and perceives how it would behave in the event of pandemic influenza. Our aim was to develop a module of questions for use in telephone health surveys on perceptions of threat of pandemic influenza, and on preparedness to comply with specific public health behaviours in the event of pandemic influenza., Methods: A module of questions was developed and field tested on 192 adults using the New South Wales Department of Health's in-house Computer Assisted Telephone Interviewing (CATI) facility. The questions were then modified and re field tested on 202 adults. The module was then incorporated into the New South Wales Population Health Survey in the first quarter of 2007. A representative sample of 2,081 adults completed the module. Their responses were weighted against the state population., Results: The reliability of the questions was acceptable with kappa ranging between 0.25 and 0.51. Overall 14.9% of the state population thought pandemic influenza was very or extremely likely to occur; 45.5% were very or extremely concerned that they or their family would be affected by pandemic influenza if it occurred; and 23.8% had made some level of change to the way they live their life because of the possibility of pandemic influenza. In the event of pandemic influenza, the majority of the population were willing to: be vaccinated (75.4%), be isolated (70.2%), and wear a face mask (59.9%). People with higher levels of threat perception are significantly more likely to be willing to comply with specific public health behaviours., Conclusion: While only 14.9% of the state population thought pandemic influenza was very or extremely likely to occur, a significantly higher proportion were concerned for self and family should a pandemic actually occur. The baseline data collected in this survey will be useful for monitoring changes over time in the population's perceptions of threat, and preparedness to comply with specific public health behaviours.

Background: Australian epidemiologists have recognised that lay readers have difficulty understanding statistical graphs in reports on population health. This study aimed to provide evidence for graph design improvements that increase comprehension by non-experts., Methods: This was a double-blind, randomised, controlled trial of graph-design interventions, conducted as a postal survey. Control and intervention participants were randomly selected from telephone directories of health system employees. Eligible participants were on duty at the listed location during the study period. Controls received a booklet of 12 graphs from original publications, and intervention participants received a booklet of the same graphs with design modifications. A questionnaire with 39 interpretation tasks was included with the booklet. Interventions were assessed using the ratio of the prevalence of correct responses given by the intervention group to those given by the control group for each task., Results: The response rate from 543 eligible participants (261 intervention and 282 control) was 67%. The prevalence of correct answers in the control group ranged from 13% for a task requiring knowledge of an acronym to 97% for a task identifying the largest category in a pie chart. Interventions producing the greatest improvement in comprehension were: changing a pie chart to a bar graph (3.6-fold increase in correct point reading), changing the y axis of a graph so that the upward direction represented an increase (2.9-fold increase in correct judgement of trend direction), a footnote to explain an acronym (2.5-fold increase in knowledge of the acronym), and matching the y axis range of two adjacent graphs (two-fold increase in correct comparison of the relative difference in prevalence between two population subgroups)., Conclusion: Profound population health messages can be lost through use of overly technical language and unfamiliar statistical measures. In our study, most participants did not understand age standardisation and confidence intervals. Inventive approaches are required to address this problem.

Background: In a climate of concern over bioterrorism threats and emergent diseases, public health authorities are trialling more timely surveillance systems. The 2003 Rugby World Cup (RWC) provided an opportunity to test the viability of a near real-time syndromic surveillance system in metropolitan Sydney, Australia. We describe the development and early results of this largely automated system that used data routinely collected in Emergency Departments (EDs)., Methods: Twelve of 49 EDs in the Sydney metropolitan area automatically transmitted surveillance data from their existing information systems to a central database in near real-time. Information captured for each ED visit included patient demographic details, presenting problem and nursing assessment entered as free-text at triage time, physician-assigned provisional diagnosis codes, and status at departure from the ED. Both diagnoses from the EDs and triage text were used to assign syndrome categories. The text information was automatically classified into one or more of 26 syndrome categories using automated "naïve Bayes" text categorisation techniques. Automated processes were used to analyse both diagnosis and free text-based syndrome data and to produce web-based statistical summaries for daily review. An adjusted cumulative sum (cusum) was used to assess the statistical significance of trends., Results: During the RWC the system did not identify any major public health threats associated with the tournament, mass gatherings or the influx of visitors. This was consistent with evidence from other sources, although two known outbreaks were already in progress before the tournament. Limited baseline in early monitoring prevented the system from automatically identifying these ongoing outbreaks. Data capture was invisible to clinical staff in EDs and did not add to their workload., Conclusion: We have demonstrated the feasibility and potential utility of syndromic surveillance using routinely collected data from ED information systems. Key features of our system are its nil impact on clinical staff, and its use of statistical methods to assign syndrome categories based on clinical free text information. The system is ongoing, and has expanded to cover 30 EDs. Results of formal evaluations of both the technical efficiency and the public health impacts of the system will be described subsequently.

Study Objective: To describe the development of the public health surveillance system for the Sydney 2000 Olympic Games; document its major findings; and discuss the implications for public health surveillance for future events., Design: Planning for the system took almost three years. Its major components included increased surveillance of communicable diseases; presentations to sentinel emergency departments; medical encounters at Olympic venues; cruise ship surveillance; environmental and food safety inspections; surveillance for bioterrorism; and global epidemic intelligence. A daily report integrated data from all sources., Setting: Sydney, Australia. Surveillance spanned the period 28 August to 4 October 2000., Participants: Residents of Sydney, athletes and officials, Australian and international visitors., Main Results: No outbreaks of communicable diseases were detected. There were around 5% more presentations to Sydney emergency departments than in comparable periods in other years. Several incidents detected through surveillance, including injuries caused by broken glass, and a cluster of presentations related to the use of the drug ecstasy, prompted further action., Conclusions: Key elements in the success of public health surveillance for the Games included its careful planning, its comprehensive coverage of public health issues, and its timely reporting and communication processes. Future systems need to be flexible enough to detect the unexpected.

Aims: To describe presentations to emergency departments during the Sydney 2000 Olympic Games for conditions related to the use of illicit drugs; to discuss the implications of such presentations for surveillance and public health action at similar events in the future., Design: Identification of target presentations in sentinel emergency departments; entry of data into a purpose-built database; and daily electronic transfer of data for central collation and analysis., Setting: Fifteen sentinel emergency departments in the greater Sydney metropolitan area for a 38-day period spanning the Sydney 2000 Olympic Games., Participants: Four hundred and twenty-four presentations to sentinel emergency departments with conditions related to illicit drug use., Measurements: Patient's age, sex, country and region of residence, location of emergency department, types of illicit drugs involved and departure status., Findings: The mean daily number of presentations for adverse events due to illicit drug use was significantly higher (13.3 versus 8.8 presentations, t = 2.2, P = 0.04) in the 2-week Olympic Games period than in the lead-up to the Games, culminating in a large peak following the closing ceremony. There was also a significant increase (5.1 versus 1.7 presentations, t = 2.8, P = 0.007) in the mean daily number of presentations related to use of ecstasy or amphetamines, whereas no change was noted in presentations related to heroin use. Over half (52%) of presentations occurred at two emergency departments in areas known as being 'hot-spots' for illicit drug use., Conclusions: Enhanced surveillance of adverse events following illicit drug use, possibly targeting known 'hot-spots', should be considered for future mass events. Advance preparation of preventive strategies, such as 'party-safe' messages, will enable rapid response to unusual patterns of illicit drug-related harm during future mass events.

This study reports chronic pain prevalence in a randomly selected sample of the adult Australian population. Data were collected by Computer-Assisted Telephone Interview (CATI) using randomly generated telephone numbers and a two-stage stratified sample design. Chronic pain was defined as pain experienced every day for three months in the six months prior to interview. There were 17,543 completed interviews (response rate=70.8%). Chronic pain was reported by 17.1% of males and 20.0% of females. For males, prevalence peaked at 27.0% in the 65--69 year age group and for females, prevalence peaked at 31.0% in the oldest age group (80--84 years). Having chronic pain was significantly associated with older age, female gender, lower levels of completed education, and not having private health insurance; it was also strongly associated with receiving a disability benefit (adjusted OR=3.89, P<0.001) or unemployment benefit (adjusted OR=1.99, P<0.001); being unemployed for health reasons (adjusted OR=6.41, P<0.001); having poor self-rated health (adjusted OR=7.24, P<0.001); and high levels of psychological distress (adjusted OR=3.16, P<0.001). Eleven per cent of males and 13.5% of females in the survey reported some degree of interference with daily activities caused by their pain. Prevalence of interference was highest in the 55--59 year age group in both males (17.2%) and females (19.7%). Younger respondents with chronic pain were proportionately most likely to report interference due to pain, affecting 84.3% of females and 75.9% of males aged 20--24 years with chronic pain. Within the subgroup of respondents reporting chronic pain, the presence of interference with daily activities caused by pain was significantly associated with younger age; female gender; and not having private health insurance. There were strong associations between having interfering chronic pain and receiving disability benefits (adjusted OR=3.31, P<0.001) or being unemployed due to health reasons (adjusted OR=7.94, P<0.001, respectively). The results show that chronic pain impacts upon a large proportion of the adult Australian population, including the working age population, and is strongly associated with markers of social disadvantage.

The Sydney 2000 Olympic Games (the XXVII Olympiad) will be the biggest peacetime event ever held in Australia. During the Games, all public health decisions will be centralised, with daily briefing sessions held to review emerging public health issues and facilitate responses. Infectious diseases will be monitored and reported through the Olympic Surveillance System, with particular attention to foodborne diseases and conditions spread via the respiratory route. This system relies heavily on the cooperation of key notifiers such as emergency departments, laboratories and general practitioners. The lessons learned during the Games, and the new and enhanced systems and linkages that have been developed to support it, will strengthen future disease surveillance in NSW.

Background: Acute upper respiratory infections are common in children who attend child care, and preventing transmission of disease in this setting depends on actions by child care staff. We set out to discover whether transmission of respiratory infections in child care could be reduced by improved infection control procedures., Methods: We performed a cluster, randomized, controlled trial of an infection control intervention conducted in child care centers in 1 city in Australia. The intervention was training of child care staff about transmission of infection, handwashing, and aseptic nosewiping technique. Implementation of the intervention was recorded by an observer. Illness was measured by parent report in telephone interviews every 2 weeks., Results: There were 311 child-years of surveillance for respiratory symptoms. By multivariable analysis, there was no significant reduction in colds in intervention center children across the full age range. However, a significant reduction in respiratory illness was present in children 24 months of age and younger. When compliance with infection control practices was high, colds in these children were reduced by 17%., Conclusions: This trial supports the role of direct transmission of colds in young children in child care. The ability of infection control techniques to reduce episodes of colds in children in child care was limited to children 24 months of age and under.

Background: Diarrheal infections are common in children who attend child care, and preventing transmission of disease in this setting depends on actions by child care staff. We set out to discover whether transmission of gastrointestinal infections in child care could be reduced by improved infection control procedures., Methods: We performed a cluster randomized, controlled trial of an infection control intervention conducted in child care centers for 1 city in Australia. The intervention was training of child care staff about transmission of infection and handwashing and focused on both staff and child behavior. Implementation of the intervention was recorded by an observer. Illness was measured by parent report in telephone interviews every 2 weeks., Results: There were 311 child-years of surveillance for diarrheal episodes. The rate of episodes of diarrhea was 1.9 per child-year in intervention centers and 2.7 per child-year in control centers. Multivariable analysis showed that diarrheal episodes were significantly reduced in intervention center children by 50%. However, the impact of the intervention was confined to children over 24 months of age. For those centers in which children's compliance with handwashing was high, diarrheal episodes were reduced by 66%., Conclusions: This trial supports education about infection control, for staff and children in child care, as a means of reducing transmission of diarrhea. Reduction in episodes of diarrhea in children in child care was limited to children over 24 months of age.

Objective: To estimate the prevalence of smoking, stage-of-change and GP advice to quit in the Sydney Lebanese community and whether these findings varied by survey method., Method: Three methods--telephone interviews using sampling from the electronic White Pages, personal interviews of a household member selected using cluster sampling and a mailed survey using an electoral roll sample--were used in separate surveys of persons born in Lebanon living in three postcode areas of Sydney in 1997., Results: Smoking prevalence was consistent across the three methods, with male smoking averaging 49% and female smoking averaging 29%. About two-thirds of smoking respondents across each of the survey methods had no plans for quitting., Conclusions: As smoking prevalence did not vary across the three sampling and survey methods used here, the simplest and most inexpensive method (the electronic White Pages and telephone surveying of identifiable ethnic surnames) should be preferred., Implications: Smoking prevalence in the Sydney Lebanese community is determined consistently using a variety of survey methods.

Objective: This study investigated the associations between parental smoking and respiratory infections in Australian children aged 0-4 years., Methods: Data from the ABS 1989-90 National Health Survey were used. The exposure variables examined were maternal, paternal and combined family smoking. Outcome variables were parent-reported chronic or recent asthma, asthma wheeze, bronchitis, influenza, common cold, cough, otitis media and other respiratory conditions. Logistic regression techniques were used to control for confounding by socio-economic status, child's sex, maternal education, place of residence, ethnicity and family size., Results: Of the 4,281 children in the sample, 45% lived in households with one or more current smokers and 29% had a mother who smoked. Maternal (but not paternal) smoking was significantly associated with asthma (OR 1.52, 95% CI 1.19-1.94) and asthma wheeze (OR 1.51, 95% CI 1.26-1.80). No other significant associations were observed. Positive and significant dose response relationships were found between the amount of maternal smoking and both asthma variables. Population attributable risks were calculated and almost 13% of asthma and asthma wheeze in 0-4 year old Australian children in 1989-90 was estimated to be due to maternal smoking., Conclusion: Large numbers of Australian children live in households with smokers. This study, like others, has shown an association between maternal smoking and respiratory illnesses in young children. Further strategies are needed to prevent or reduce young children's exposure to environmental tobacco smoke in their homes.

In this study, we compared the likely cost-effectiveness of alternative strategies for controlling a school-based measles outbreak. The analysis involved assessing the expected costs and number of cases in a school-based outbreak of measles, with no intervention and with each of six control strategies. The marginal cost per case prevented ranged from $32.90 when only previously unvaccinated school children were offered vaccination to $6795 when vaccination was extended to the siblings of school children aged 6 to 12 months. This study provided further evidence of the cost-effectiveness of vaccination in outbreak control, and yielded useful information to inform control strategies in the event of a school-based outbreak. Decisions about which groups of children to aim at and whether to conduct school-based clinics will be influenced by local circumstances, particularly the baseline measles vaccination rate and the measles attack rate among infants.

An outbreak of legionellosis associated with a hotel in Sydney, Australia, and the subsequent epidemiological and environmental investigations are described. Four cases of Legionnaires' disease were notified to the Public Health Unit. A cross-sectional study of 184 people who attended a seminar at the hotel was carried out. Serological and questionnaire data were obtained for 152 (83%) of these. Twenty-eight (18%) respondents reported symptoms compatible with legionellosis. Thirty-three subjects (22%) had indirect fluorescent antibody (IFA) titres to Legionella pneumophila serogroup 1 (Lp-1) of 128 or higher. The only site which those with symptoms of legionellosis and IFA titre > or = 128 were more likely to have visited than controls was the hotel car park (adjusted odds ratio [OR] 14.7, 95% confidence interval [CI]: 1.8-123.1). Those with symptoms compatible with legionellosis, but whose IFA titres were < 128 were also more likely to have visited the hotel car park (adjusted OR 4.4, 95% CI: 1.5-12.9). Seroprevalence of Lp-1 antibodies was higher in those who attended the seminar than in a population sample of similar age. Findings suggested that the 4 cases represented a small fraction of all those infected, and highlighted difficulties in defining illness caused by Lp-1 and in interpreting serology.

Cases of measles reported separately by doctors, hospitals, laboratories, and others are treated as separate captures and releases of the population of children aged up to 10 years who have been infected by measles in a recent epidemic. Loglinear models are used to assess the adequacy of fit of various models for capture-recapture and the size of the epidemic in different age groups is estimated.

Objective: To investigate outbreaks of diarrhoeal illness in children attending long-daycare centres (LDCs), to characterise parasitic, bacterial and viral isolates from the children's faeces and to identify individual and LDC risk factors for diarrhoea., Design: Eleven-month prospective case-control study of diarrhoeal outbreaks among children in LDCs., Subjects: 2368 children attending 35 LDCs in the western Sydney area., Main Outcome Measures: Frequency of diarrhoeal outbreaks, rate of attack and spread to family members; pathogens isolated from stools; and individual and LDC risk factors., Results: The overall incidence of diarrhoeal disease was low (0.28 outbreaks per centre per year and 0.056 outbreak-associated cases per child-year). Attack rates during outbreaks varied widely (4%-55%; mean, 15%), as did secondary spread rates to family members (1%-15%; mean, 9%). Pathogens were isolated from 7% of symptomatic children and 7% of controls; no outbreak was shown to be caused by a recognised pathogen. Children with outbreak-associated diarrhoeal illness were more likely to have suffered vomiting, poor appetite, lack of energy, fever and to have taken antibiotics in the previous week than other children. Hygiene practices varied widely among centres., Conclusions: We found low incidence and morbidity from diarrhoeal illness in Australian urban LDCs. Diarrhoea in children in LDCs may be caused predominantly by non-infectious factors such as diet and antibiotic exposure. Current hygiene measures in LDCs seem adequate to prevent and contain outbreaks of infectious diarrhoea.

Objectives: To determine the effectiveness of measles vaccine during a measles outbreak, and to assess whether age at vaccination was a risk factor for measles vaccine failure., Design: A matched case-control study., Setting: The five primary schools in western Sydney with the largest number of measles cases during the June to December 1993 outbreak., Subjects: Seventy-nine children aged 5-9 years with an illness consistent with a clinical definition for measles. Two controls per case were selected from children in the same classroom., Main Outcome Measures: Estimated measles vaccine effectiveness by age of the child at vaccination and vaccination status: "unvaccinated"; "parental recall" (parents stated the child was vaccinated but no record could be found); and "record" (record including date of vaccination available)., Results: The estimated vaccine effectiveness was 94% (95% confidence interval [CI], 83%-98%) in the "record" group, and 81% (95% CI, 46%-93%) in the "parental recall" group. Vaccine effectiveness did not differ significantly with age at vaccination (under 12 months of age 96% [64%-99%]; 12-14 months 95% [81%-99%]; and 15 months and over 93% [80%-98%])., Conclusion: Vaccination records should be used to calculate a vaccine's effectiveness as parental recall may not be sufficiently accurate. The high vaccine effectiveness in the "record" group (94%) makes it unlikely that low vaccine effectiveness was the cause of the outbreak. More effort is needed to increase vaccine coverage to at least 95% in all population subgroups.

The genetic structure of beta-haemolytic Lancefield group C streptococci isolated from horses in Australia was examined by multilocus enzyme electrophoresis. The 249 isolates comprised 70 classified phenotypically as Streptococcus equi subspecies equi, 177 classified as S equi subspecies zooepidemicus and two which were unclassifiable. Forty-one electrophoretic types were identified which could be classified into three major clusters, A, B and C. Of the isolates, 178 fell into cluster B (types 4 to 22) and lay within a genetic distance of 0.36. Sixty-nine of the 70 S equi subspecies equi isolates fell into type 12, which suggests that they were members of a single clone, and the isolates from abscesses were significantly more likely to belong to type 12 than those from horses with no clinical signs (P < 0.001). There were no other significant associations between electrophoretic types or clusters and the isolation of the organism from particular sites. These data suggested that S zooepidemicus may be the archetypal species from which the clone designated subspecies equi has been derived. If isolates of the subspecies equi from other geographical regions also prove to be members of electrophoretic type 12, this hypothesis would be strengthened.

We surveyed the directors of all 92 long day care centres in western Sydney to document the occurrence of communicable disease outbreaks during 1992 and to identify risk factors for the occurrence of these outbreaks. A total of 6092 children were enrolled at the centres, of whom 530 (8.7%) were less than 3 years old. Most centres (80.4%) reported at least one outbreak of communicable disease. Diarrhoea was the most commonly reported outbreak type (60 outbreaks), followed by conjunctivitis, head louse infestation and chicken pox (46, 44 and 24 outbreaks, respectively). Chicken pox outbreaks had the largest mean number of cases per outbreak (9.6) and the longest mean outbreak duration (4.4 weeks). Centres with a large total enrollment (50 or more children), those that were open for 12 or more hours each day and those which had commenced operating in 1990 or more recently were generally more likely to report outbreaks, particularly of diarrhoea. The vast majority of communicable disease outbreaks (92.1%) were handled by day-care staff without seeking outside assistance. Day-care centre directors may be unaware of the health services that could help them. We need to work more closely with long day care centres, and to focus preventative efforts on large centres, those open for long hours, and newly opened centres.

Equid herpesvirus-4 (EHV-4) was detected in nasal swabs taken from foals using a PCR based test and this information used to study the epidemiology of EHV-4 disease on three Australian Thoroughbred stud farms in NSW in 1992. There was a very high level of agreement (kappa value of 0.84) between the PCR results and virus isolation using cell culture techniques. There was a strong seasonal distribution of EHV-4 shedding. Twenty-five of 26 positive samples were collected in January and March with the remaining positive sample collected in February. Foals with clinical signs of upper respiratory tract infection per se were no more likely to be shedders of EHV-4 (odds ratio [OR] 1.4, 95% confidence limits [CL] 0.5-3.8). However, EHV-4 was more likely to be isolated from foals exhibiting copious serous or mucopurulent nasal discharge than those with no clinical signs (OR 4.6, 95% CL 1.1-19.0 and OR 2.5, 95% CL 0.8-8.0, respectively). The month of the year was more important than weaning or age as a risk factor for excretion of EHV-4. Male foals and those with a history of respiratory disease that had required veterinary treatment were more likely to shed EHV-4.

Objectives: To provide estimates of the numbers of New South Wales children in Family Day Care who may be exposed to environmental tobacco smoke while attending day care; to describe existing smoking policies; and to analyse these policies with the aim of providing guidelines for smoking policy in Family Day Care., Setting: All 109 Family Day Care schemes in NSW., Method: Scheme coordinators were sent a questionnaire regarding the proportion of carers who smoked while caring for children; the nature, enforcement and experience of smoking policies; and barriers to implementation of a no-smoking policy., Results: A mean of 10% of Family Day Care caregivers were reported to smoke while caring for children (range, 0-60%). An estimated 2045 children were potentially exposed to environmental tobacco smoke in the 86 schemes which provided this information. Thirty-five per cent of schemes had formal no-smoking policies. A range of advantages, disadvantages and perceived practical and legal barriers to implementation of a no-smoking policy in Family Day Care were described. Forty-four per cent of schemes with no-smoking policies reported no implementation problems., Conclusions: There is considerable potential for exposure of children to environmental tobacco smoke in Family Day Care homes. There is legal support for Family Day Care caregivers not to expose children under their care to environmental tobacco smoke. A formal (and enforced) no-smoking policy should exist in every Family Day Care scheme, and a "top-down" directive is most likely to be successful. The issue of other smokers in the caregiver's household needs to be specifically addressed in any such directive.

A questionnaire survey of 179 horse studs in New South Wales was conducted to estimate the incidence of strangles during 1985 to 1988, to identify risk factors for strangles outbreaks and to assess the effect of strangles vaccination. Forty-nine of the studs (27.4%) had at least one strangles outbreak during this period and 62 studs (34.6%) had at least one case of strangles. The average incidence of strangles was 2.1 cases per 100 horses per year. The risk of strangles increased progressively with the total horse population and rose markedly when more than 100 mares had been served in the 1988-89 season. Certain types of feeders, fences and water sources were also significantly associated with outbreaks of strangles. Strangles vaccine was used on 63 studs (35.2%). Thirty-seven of these (58.7%) used the manufacturer's recommended vaccination regime. When other risk factors were taken into account, vaccination had no significant effect on the likelihood of a strangles outbreak.

Five cases of clinical Q fever were identified amongst students and staff of a Somerset secondary school between 23 October 1987 and 21 December 1987. Five goats which were kept at the school were found to have antibodies to Coxiella burnetii phase II. A cross-sectional study was conducted at the school in July 1988. A single CF test was used to identify evidence of prior infection, and a self-administered questionnaire was used to collect data on exposure variables and illness during 1987. Four hundred and ninety-nine eligible subjects took part in the study, and serological information was obtained from 461 of these. Eighty-seven subjects (18.9%) had CF titres of 20 or greater. It was estimated that only 1 in every 30 individuals with evidence of past C. burnetii infection had been recognized as a clinical case of Q fever. Antibody positive subjects were more likely to have been off school sick and to report having suffered chest pain than negative subjects. Contact with school animals, specifically cleaning the school poultry, collecting their eggs and visiting a school goat on the day of kidding, was associated with the presence of antibodies to C. burnetii. However, a large proportion of the antibody positives (24.2%) had no known contact with the school animals. Spread of organisms, either wind-borne or in straw or manure, may have been responsible for the high prevalence of unexplained infection.