Factors associated with hospitalisations and deaths of residential aged care residents with COVID-19 during the Omicron (BA.1) wave in Queensland.

OBJECTIVE: To identify characteristics associated with the hospitalisation and death of people with COVID-19 living in residential aged care facilities (RACFs). DESIGN: Retrospective cohort study. SETTING, PARTICIPANTS: All confirmed (polymerase chain reaction testing) or probable SARS-CoV-2 infections (rapid antigen tests) in residents of the 86 RACFs in the Metro South Hospital and Health Service area (southeast Queensland), 13 December 2021 - 24 January 2022. MAIN OUTCOME MEASURES: Hospitalisation within 14 days or death within 28 days of COVID-19 diagnosis. RESULTS: Of 1071 RACF residents with COVID-19, 151 were hospitalised within 14 days and 126 died within 28 days of diagnosis. Likelihood of death increased with age (per five years: adjusted odds ratio [aOR], 1.38; 95% confidence interval [CI], 1.21-1.57), but not that of hospitalisation. Men were more likely to be hospitalised (aOR, 1.7; 95% CI, 1.2-2.4) or die (aOR, 2.5; 95% CI, 1.7-3.6) than women. The likelihood of hospitalisation was greater for those with dementia (aOR, 1.9; 95% CI, 1.2-3.0), heart failure (aOR, 1.7; 95% CI, 1.1-2.7), chronic kidney disease (aOR, 1.7; 95% CI, 1.1-2.5), or asthma (aOR, 2.2; 95% CI, 1.2-3.8). The likelihood of death was greater for residents with dementia (aOR, 2.2; 95% CI, 1.3-3.7), diabetes mellitus (aOR, 1.9; 95% CI, 1.3-3.0), heart failure (aOR, 2.0; 95% CI, 1.1-3.3), or chronic lung disease (aOR, 1.7; 95% CI, 1.1-2.7). The likelihood of hospitalisation and death were each higher for residents who had received two or fewer vaccine doses than for those who had received three doses. CONCLUSIONS: Most characteristics that influenced the likelihood of hospitalisation or death of RACF residents with COVID-19 were non-modifiable factors linked with frailty and general health status. Having received three COVID-19 vaccine doses was associated with much lower likelihood of hospitalisation or death.

Household transmission of the Delta COVID-19 variant in Queensland, Australia: a case series.

Household transmission plays a key role in the spread of COVID-19 through populations. In this paper, we report on the transmission of COVID-19 within households in a metropolitan area in Australia, examine the impact of various factors and highlight priority areas for future public health responses. We collected and reviewed retrospective case report data and follow-up interview responses from households with a positive case of the Delta COVID-19 variant in Queensland in 2021. The overall secondary attack rate (SAR) among household contacts was 29.6% and the mean incubation period for secondary cases was 4.3 days. SAR was higher where the index case was male (57.9% vs. 14.3%) or aged ≤12 years (38.7% vs. 17.4%) but similar for adult contacts that were double vaccinated (35.7%) and unvaccinated (33.3%). Most interview participants emphasised the importance of clear, consistent and compassionate health advice as a key priority for managing outbreaks in the home. The overall rate of household transmission was slightly higher than that reported in previous studies on the wild COVID-19 variant and secondary infections developed more rapidly. While vaccination did not appear to affect the risk of transmission to adult subjects, uptake in the sample was ultimately high.

Protocol for a winter sentinel surveillance program of notifiable respiratory viruses in Queensland.

BACKGROUND: With the reduction in access to polymerase chain reaction (PCR) testing and changes in testing guidelines in Australia, a reduced number of people are seeking testing for coronavirus disease (COVID-19), limiting the opportunity to monitor disease transmission. Knowledge of community transmission of COVID-19 and other respiratory viruses is essential to better predict subsequent surges in cases during the pandemic to alert health services, protect vulnerable populations and enhance public health measures. We describe a methodology for a testing-based sentinel surveillance program to monitor disease in the community for early signal detection of SARS-CoV-2 and other respiratory viruses. METHODS/DESIGN: A longitudinal active testing-based sentinel surveillance program for respiratory viruses (including SARS-CoV-2, influenza A, influenza B and Respiratory Syncytial Virus) will be implemented in some regions of Queensland. Adults will be eligible for enrolment if they are part of specific community groups at increased risk of exposure and have not had a COVID-19 infection in the last 13 weeks. Recruitment via workplaces will occur in-person, via email and through online advertisement. Asymptomatic participants will be tested via PCR for SARS-CoV-2 infection by weekly self-collected nasal swabs. In addition, symptomatic participants will be asked to seek SARS-CoV-2 and additional respiratory virus PCR testing at nominated COVID-19 testing sites. SARS-CoV-2 and respiratory virus prevalence data will be analysed weekly and at the end of the study period. DISCUSSION: Once implemented, this surveillance program will determine the weekly prevalence of COVID-19 and other respiratory viruses in the broader community by testing a representative sample of adults, with an aim to detect early changes in the baseline positivity rate. This information is essential to define the epidemiology of SARS-CoV-2 in the community in near-real time to inform public health control measures and prepare health services and other stakeholders for a rise in service demand.