The increasing health burden of Legionella Pneumophila in NSW.

BACKGROUND: Legionella pneumophila can cause severe respiratory disease and is notifiable in NSW. An analysis of notifications linked to hospitalisation and death data over the period 2010-2022 was conducted to determine the burden of disease and any association with the introduction of NSW regulatory changes in 2018. METHODS: Cases were retrospectively identified from the Notifiable Conditions Records for Epidemiology and Surveillance (NCRES). Data on related morbidity and mortality were obtained from linked data within the NSW Communicable Disease Register (CDR). The impact of the regulatory change was evaluated by analysing monthly count data using an interrupted time series analysis. RESULTS: A total of 928 cases were notified with 84% admitted to hospital. Annual adjusted notification and admission rates increased over the period from 4.40 to 7.92 cases and 3.72 to 7.20 admissions, per 1,000,000 population, respectively. The mean length of hospital stay (LOS) was 14 days with a median of 8 days (range 1-262 days). Time series analysis identified an underlying increasing time trend in cases notified per month with an IRR of 1.069 (95% ci 0.751-1.523) post 2018 regulatory implementation. CONCLUSION: L. pneumophila is posing an increasing burden of disease with an underlying upward trend in notification incidence despite the introduction of regulatory changes in 2018. IMPLICATION FOR PUBLIC HEALTH PRACTICE: This study demonstrates how linking notification, hospitalisation and death data can measure the health burden of a notifiable condition. Furthermore, time-series analysis using these data is able to identify underlying temporal trends and evaluate policy changes.

Using the Australian Immunisation Register to support general practices to improve childhood vaccination rates.

BACKGROUND AND OBJECTIVES: Strategies to improve vaccination rates have been implemented with considerable benefits. The main objective of this study was to assess the impact of a supported general practice intervention to 'catch up' overdue children. METHOD: Between 2017 and 2018, a public health nurse visited 23 general practices with high numbers of overdue children to assist staff identify and follow up truly overdue children. A comparison group consisted of a random sample of overdue children from other practices. The intervention was assessed by reviewing Australian Immunisation Register (AIR) records in 2019. RESULTS: Although the intervention group had a significantly higher proportion of children who had their AIR records corrected for vaccines administered prior to the initial practice visit, the intervention did not result in higher vaccination rates. DISCUSSION: Support to general practices can improve vaccination data on the AIR; however, simple reminders alone are unlikely to increase vaccination rates for truly overdue children.

Identifying a more severe emergent COVID-19 variant using Emergency Departments' routinely collected clinical measures.

Objective: To determine whether a clinical scoring system (the mPRIEST score) could be used to identify an emerging coronavirus disease 2019 (COVID-19) variant with increased clinical severity. Design: Cross sectional study comparing two time periods (Delta and Omicron waves). Setting: Public Emergency Departments in Northern Sydney Local Health District. Participants: Patients presenting during August 2021 (Delta wave) and January 2022 (Omicron wave) with confirmed COVID-19. Data on age, gender, temperature, heart rate, systolic blood pressure, respiratory rate, oxygen saturation and mental status were extracted from patients' electronic medical records to assess clinical disease severity at presentation. Main outcome measures: Modified Pandemic Respiratory Infection Emergency System Triage (mPRIEST) score calculated using routinely collected data. Results: A sample of 262 records of COVID-19 positive patients presenting during the Delta and initial Omicron waves were reviewed with 205 having COVID-19 as their primary diagnosis. During the Delta wave 48.1% had scores above 4 compared to 35.1% for the Omicron wave (p = 0.03). The median score was also significantly higher for the Delta group (4 vs 3; p = 0.01). Hospitalisations, admissions to ICU and deaths during admission were higher among patients presenting during the Delta wave than among those presenting during the Omicron wave. Conclusion: The mPRIEST score was significantly higher for patients for whom the predominant circulating variant was Delta than those for whom the predominant circulating variant was Omicron. This finding is consistent with international reporting of severity measured by hospital admission data and demonstrates the score's possible ability to identify an emergent strain with higher morbidity and mortality.

Pertussis Morbidity in Children 12-59 Months of Age: A NSW Public Health Network Study.

BACKGROUND: Pertussis continues to be a significant public health problem despite high levels of vaccination. Although hospitalizations and deaths among children greater than 12 months of age are much less frequent than among infants less than 6 months of age, only limited information is available for this age group on other measures of morbidity. METHODS: A cross-sectional study with a 6-week follow-up component was conducted in New South Wales, Australia in 2017 to measure morbidity among children 12-59 months of age notified to health authorities. Measures used included cough duration, cough severity, constitutional symptoms and impacts on the family. Associations between these outcomes and age group, vaccination status, asthma, treatment and family structure were explored. RESULTS: Three hundred and five of 472 (65%) notified cases were interviewed at baseline with approximately 20% having a severe cough with no trend in prevalence across age groups. Forty-eight percent of cases had experienced 3 or more constitutional symptoms with rates significantly higher among younger children. Children who had received an 18-month booster vaccination were significantly less likely to experience 3 or more constitutional symptoms (odds ratio: 0.46, 95% confidence interval: 0.22-0.97). Fifty-one percent of cases were still coughing at 6 weeks. One-third of carers initially reported having disrupted sleep 4 or more nights per week with substantial disruption to carers' sleep still recorded at 6 weeks. CONCLUSIONS: Substantial morbidity was observed in this age group with some evidence that the reintroduction of an 18-month acellular pertussis booster lessened disease severity.