Evaluation of the usability, content, readability and cultural appropriateness of online alcohol and other drugs resources for Aboriginal and Torres Strait Islander Peoples in New South Wales, Australia.

OBJECTIVES: This study aimed to analyse the usability, content, readability and cultural appropriateness of alcohol and other drugs (AODs) resources for Aboriginal and Torres Strait Islander Peoples in New South Wales (NSW), Australia. OUTCOME MEASURES: The content of 30 AOD resources for Aboriginal and Torres Strait Islander Peoples was analysed according to the following criteria: general characteristics; elements of graphical design and written communication; thoroughness and content; readability (Flesch-Kincaid grade level (FKGL), Gunning Fog index (Fog), Simplified Measure of Gobbledygook and Flesch Reading Ease); and cultural appropriateness. RESULTS: Most resources displayed good usability, depicted by the use of headings and subheadings (n=27), superior writing style (n=19), relevant visuals (n=19) and use of colour support (n=30). However, some resources used at least one professional jargon (n=13), and many did not provide any peer-reviewed references (n=22). During content analysis, 12 resources were categorised into the alcohol group and 18 resources in the other drugs group. Impact of alcohol during pregnancy and breast feeding (n=12) was the most common included topics in the resources related to alcohol, while the physical impact of drugs (n=15) was the most discussed topics among the other drugs group. Based on the FKGL readability score, 83% of resources met the recommended reading grade level of 6-8 by NSW Health. Many resources (n=21) met at least half of the cultural appropriateness elements of interest. However, less than one-third were developed in collaboration with the local community (n=9), used local terms (n=5), targeted the local community (n=3), included an Aboriginal voice (n=2) and addressed the underlying cause (n=1). CONCLUSIONS: Many AOD resources are developed specifically for Aboriginal and Torres Strait Islander Peoples, but their usability, content and readability differed, and they were not culturally appropriate for all communities. Development of a standardised protocol for resource development is suggested.

Horizon scanning, rapid reviews and living evidence to support decision-making: lessons from the work of the Critical Intelligence Unit in New South Wales, Australia during the COVID-19 pandemic.

The COVID-19 pandemic has seen an increase in rapidly disseminated scientific evidence and highlighted that traditional evidence synthesis methods, such as time and resource intensive systematic reviews, may not be successful in responding to rapidly evolving policy and practice needs. In New South Wales (NSW) Australia, the Critical Intelligence Unit (CIU) was established early in the pandemic and acted as an intermediary organisation. It brought together clinical, analytical, research, organisational and policy experts to provide timely and considered advice to decision-makers. This paper provides an overview of the functions, challenges and future implications of the CIU, particularly the Evidence Integration Team. Outputs from the Evidence Integration Team included a daily evidence digest, rapid evidence checks and living evidence tables. These products have been widely disseminated and used to inform policy decisions in NSW, making valuable impacts. Changes and innovations to evidence generation, synthesis and dissemination in response to the COVID-19 pandemic provide an opportunity to shift the way evidence is used in future. The experience and methods of the CIU have potential to be adapted and applied to the broader health system nationally and internationally.

Using silent area analysis to inform a COVID-19 public health response in Hunter New England, regional New South Wales.

Abstract: In 2020 and 2021, in the context of nationwide efforts to suppress SARS CoV-2 virus transmission while awaiting a vaccine, public health teams were responsible for finding and isolating all cases and quarantining their contacts. The success of this strategy required very high case ascertainment and thus, by inference, ready access to PCR testing, even in large rural areas such as Hunter New England in New South Wales. 'Silent area' analysis entailed the scheduled regular comparison of case and testing rates at local-government-area resolution against larger area and state-wide rates. This analysis provided an easily understood metric for identifying areas with lower testing rates, and for direction of surging of local testing capacity in such areas, by the local health district in partnership with public health services and private laboratory services. Complementary intensive community messaging was also utilised to promote increased testing in identified areas.

Lessons learned from keeping NSW's prisons COVID-free.

PURPOSE: New South Wales (NSW) correctional system houses 30% of prisoners in Australia and at this time has only had a single documented case of COVID-19 amongst its prisoner population. The coordinated response by Justice Health and Forensic Mental Health Network (The Network) undertaken with the support of NSW Ministry of Health, in partnership with Corrective Services NSW (CSNSW), Youth Justice and private jails has ensured that the NSW correctional system has remained otherwise COVID-free. DESIGN/METHODOLOGY/APPROACH: A research study of how a range of partners which support the operations of NSW Correctional System developed an effective approach for the prevention a COVID-19 epidemic amongst its inmates. FINDINGS: Establishment of effective partnerships, early coordination of representatives from all aspects of the NSW correctional system, limited access to the correctional environment, reduced prison population and strict isolation of all new receptions have all contributed to maintaining this COVID-free status despite other NSW settings with similar risk profiles, such as aged care facilities and cruise ship arrivals, experiencing serious outbreaks. RESEARCH LIMITATIONS/IMPLICATIONS: Although Australia/New Zealand context of suppressed community infection rates for COVID-19 (which are approaching elimination in some jurisdictions) is in contrast to the situation in other parts of the world, the principles described in this paper will be useful to most other correctional systems. PRACTICAL IMPLICATIONS: Modelling was used to underline our approach and reinforced the veracity of following this approach. ORIGINALITY/VALUE: The Network and CSNSW has been able to mount an effective, integrated response to the COVID-19 pandemic, which has been sustainable through the first peak of COVID-19 cases. This case study catalogues the process of developing this response and details each intervention implemented with inventive use of tables to demonstrate the impact of the range of interventions used.

A Pilot Randomised Controlled Trial to Increase the Sustainment of an Indoor-Outdoor-Free-Play Program in Early Childhood Education and Care Services: A Study Protocol for the Sustaining Play, Sustaining Health (SPSH) Trial.

Early Childhood Education and Care (ECEC) settings are important environments to support children's physical activity (PA). In 2021, COVID-19 regulations recommended the provision of indoor-outdoor free-play programs in ECEC settings to reduce the transmission of COVID-19, resulting in an increased uptake of this practice. As the context has since changed, research suggests that ECEC services could cease the implementation of these practices. Therefore, this pilot randomised controlled trial (RCT) aims to examine the feasibility, acceptability, and impact of a sustainment strategy to ensure the ongoing implementation (sustainment) of ECEC-delivered indoor-outdoor free-play programs. Twenty ECEC services located in New South Wales, Australia that have implemented indoor-outdoor free-play programs since the release of COVID-19 guidelines will be recruited. The services will be randomly allocated either the sustainment strategy or usual care. The "Sustaining Play, Sustaining Health" program consists of eight strategies, developed to address key barriers against and facilitators of sustainment informed by the Integrated Sustainability Framework. The outcomes will be assessed via internal project records, staff surveys, and a self-reported measure of free play. This study will provide important data to support the performance of a fully powered trial within Australian ECEC settings and to inform the development of future sustainment strategies.

Emergent Omicron BR.2.1 sublineage of SARS-CoV-2 in New South Wales, Australia: a subvariant with high fitness but without increased disease severity.

OBJECTIVES: To describe the epidemiology and impact of Omicron BR.2.1, an emergent SARS-CoV-2 Omicron BA.2.75 sublineage displaying high fitness compared to other cocirculating subvariants in New South Wales, Australia. METHODS: From September 01 to November 26, 2022, 4971 SARS-CoV-2 consensus genomes from unique patients were generated, and correlated with international travel and reinfection history, and admission to the intensive care unit. RESULTS: BR.2.1 became the predominant variant by late November, and was responsible for a significantly higher proportion of community-acquired cases during the study period (55.1% vs 38.4%, P < 0.001). Reinfections (defined as occurring between 6 and 24 weeks after a prior diagnosis of COVID-19) were significantly higher among BR.2.1 compared to non-BR.2.1 infected persons (17.0% vs 6.0%, P < 0.001). BR.2.1 cases were also significantly younger compared to non-BR.2.1 (median age 48 years (interquartile range [IQR] 32) vs 53 years (IQR 32), P = 0.004). The proportion of patients admitted to the intensive care unit with BR.2.1 was not significantly higher than other subvariants (2.3% vs 2.0%, P = 0.717). CONCLUSION: Having emerged locally within New South Wales, BR.2.1 caused a significant number of SARS-CoV-2 reinfections, but with disease severity comparable with other currently circulating lineages. Given its rapid rise in prevalence, BR.2.1 has the potential to become established internationally.

Racially minoritized people's experiences of racism during COVID-19 in Australia: A qualitative study.

OBJECTIVE: Drawing from a broader study exploring how New South Wales community members from racially minoritized backgrounds experienced living through a pandemic, this paper reports specifically on experiences of racism during the COVID-19 pandemic in 2020. METHODS: Using an in-depth, qualitative interpretive approach, 11 semi-structured interviews and one focus group hosting three participants (n=14) were held via an online videoconferencing platform from September to December 2020. Inductive thematic analysis was undertaken using QRS NVivo as a data management tool. RESULTS: Racism was heightened during the pandemic and experienced in various ways by racially minoritized peoples in New South Wales. All participants in this research cited experiences of racism that impacted their wellbeing during COVID-19. These experiences are represented by the following four themes: experiencing racism is common; how racisms are experienced; increased fear of racism during COVID-19; and ways of coping with racisms. CONCLUSIONS: Racism was heightened during the pandemic and generated fear and anxiety that prevented racially minoritized peoples from participating in everyday life. IMPLICATIONS FOR PUBLIC HEALTH: Messaging from broader public platforms must be harnessed to stop the spread of moral panic so that during times of pandemic, public health strategies need only confirmation, not creation.

COVID-19 Vaccine Uptake by Infection Status in New South Wales, Australia.

Using linked public health data from Australia to measure uptake of COVID-19 vaccination by infection status, we found coverage considerably lower among infected than uninfected persons for all ages. Increasing uptake of scheduled doses, including among previously infected persons after the recommended postinfection delay, is needed to reduce COVID-19 illness rates.

Preparing for the Next Pandemic: An After-Action Review of Infection Prevention and Control Audit Strategies Within Airport and Hotel Quarantine Program.

BACKGROUND: Effective infection prevention and control (IPAC) practices within the New South Wales (NSW) Airport Operations and Hotel Quarantine Program (Quarantine Program) were required to mitigate the risk of COVID-19 being transmitted to staff, other guests, contractors, and the community. METHOD: The Quarantine Program relied on complex logistical arrangements and an end-to-end process that included all steps from the time travelers boarded the returning flight until completion of the quarantine period. This required compliance with relevant IPAC standards historically reserved for health care and the implementation of a quality assurance audit framework. RESULTS: The Clinical Excellence Commission (CEC) as the NSW Health Pillar for quality and safety and the lead in IPAC provided training and resources coupled with an IPAC quality audit framework after program commencement. CONCLUSION: This approach ensured a clear governance structure and a regular review process to minimize risk and support continuous improvement within the program.

Real-time analysis of hospital length of stay in a mixed SARS-CoV-2 Omicron and Delta epidemic in New South Wales, Australia.

BACKGROUND: The distribution of the duration that clinical cases of COVID-19 occupy hospital beds (the 'length of stay') is a key factor in determining how incident caseloads translate into health system burden. Robust estimation of length of stay in real-time requires the use of survival methods that can account for right-censoring induced by yet unobserved events in patient progression (e.g. discharge, death). In this study, we estimate in real-time the length of stay distributions of hospitalised COVID-19 cases in New South Wales, Australia, comparing estimates between a period where Delta was the dominant variant and a subsequent period where Omicron was dominant. METHODS: Using data on the hospital stays of 19,574 individuals who tested positive to COVID-19 prior to admission, we performed a competing-risk survival analysis of COVID-19 clinical progression. RESULTS: During the mixed Omicron-Delta epidemic, we found that the mean length of stay for individuals who were discharged directly from ward without an ICU stay was, for age groups 0-39, 40-69 and 70 +, respectively, 2.16 (95% CI: 2.12-2.21), 3.93 (95% CI: 3.78-4.07) and 7.61 days (95% CI: 7.31-8.01), compared to 3.60 (95% CI: 3.48-3.81), 5.78 (95% CI: 5.59-5.99) and 12.31 days (95% CI: 11.75-12.95) across the preceding Delta epidemic (1 July 2021-15 December 2021). We also considered data on the stays of individuals within the Hunter New England Local Health District, where it was reported that Omicron was the only circulating variant, and found mean ward-to-discharge length of stays of 2.05 (95% CI: 1.80-2.30), 2.92 (95% CI: 2.50-3.67) and 6.02 days (95% CI: 4.91-7.01) for the same age groups. CONCLUSIONS: Hospital length of stay was substantially reduced across all clinical pathways during a mixed Omicron-Delta epidemic compared to a prior Delta epidemic, contributing to a lessened health system burden despite a greatly increased infection burden. Our results demonstrate the utility of survival analysis in producing real-time estimates of hospital length of stay for assisting in situational assessment and planning of the COVID-19 response.

Vaping product access and use among 14-17-year-olds in New South Wales: a cross-sectional study.

OBJECTIVES: We assessed access to vaping products and types of products used and the factors associated with vaping and smoking among young people in the state of New South Wales (NSW), Australia. METHODS: A cross-sectional survey was conducted with a sample of 721 young people aged 14 to 17 years from NSW recruited through online panels. Poisson regression with robust variance was used to estimate relative risks of ever-vaping and ever-smoking. RESULTS: Almost one-third of the sample (32%, n=233) reported being an ever-vaper, of which more than half (54%) had never smoked prior to starting vaping. Ever-vaping was independently associated with age and being Aboriginal or Torres Strait Islander, and ever-smoking was independently associated with being male. Ever-smokers were seven times more likely to be ever-vapers than those who had never smoked, and ever-vapers were 18 times more likely to be ever-smokers than those who had never vaped. Among ever-vapers who reported which type of device they were using, 86% reported the use of disposable products. "Flavourings and taste" was rated as the most important characteristic of vapes. More than half of ever-vapers reported getting the last vape they used from their friends (55%, n=130). More than half of ever-vapers had used a vape that they knew contained nicotine (53%, n=123). CONCLUSIONS: Vaping was the strongest risk factor for smoking, and vice versa, suggesting there is not a straightforward, unidirectional relationship between vaping and smoking in young people. Young people appear to be readily accessing nicotine vaping products, which are often disposable and flavoured, through both social and commercial channels. IMPLICATIONS FOR PUBLIC HEALTH: Stronger enforcement of federal and state policies designed to protect young people from vaping products is urgently needed.

Weather extremes associated with increased Ross River virus and Barmah Forest virus notifications in NSW: learnings for public health response.

OBJECTIVE: To examine the sequence of environmental and entomological events prior to a substantial increase in Ross River virus (RRV) and Barmah Forest virus (BFV) notifications with a view to informing future public health response. METHODS: Rainfall, tidal, mosquito and human arboviral notification data were analysed to determine the temporality of events. RESULTS: Following two extremely dry years, there was a substantial increase in the abundance of mosquitoes along coastal New South Wales (NSW) two weeks after a significant rainfall event and high tides in February 2020. Subsequently, RRV and BFV notifications in north east NSW began to increase eight and nine weeks respectively after the high rainfall, with RRV notifications peaking 12 weeks after the high rainfall. CONCLUSIONS: Mosquito bite avoidance messaging should be instigated within two weeks of high summer rainfall, especially after an extended dry period. IMPLICATIONS FOR PUBLIC HEALTH: Intense summertime rain events, which are expected to increase in frequency in south-east Australia with climate change, can lead to significant increases in arboviral disease. These events need to be recognised by public health practitioners to facilitate timely public health response. This has taken on added importance since the emergence of Japanese encephalitis virus in southeastern Australia in 2022.

A Narrative Inquiry into the Practices of Healthcare Workers' Wellness Program: The SEED Experience in New South Wales, Australia.

The 2019-2020 Australian bushfires followed by the COVID-19 pandemic brought the significant mental health implications of working in healthcare to the fore. The importance of appropriate support services to ensure the resilience and recovery of healthcare workers has been highlighted. In response to healthcare staff experiences during the bushfires, the SEED Wellness Program was created in 2020 in the Illawarra Shoalhaven Local Health District in New South Wales, Australia. SEED used a participant-led design to engage healthcare staff in workplace-based restorative activities. Guided by practice theory, this study aimed to identify and describe SEED wellness practices that supported healthcare staff. Thirty-three healthcare workers participated in focus groups or individual interviews between June 2021 and March 2022. The analysis involved inductive thematic individual and collective exploration of SEED practices, including co-analysis with participants. Eight core practices that supported participants' wellbeing were identified, including responsive and compassionate leading, engaging staff at every stage of the recovery process, creating a sense of connection with others, and collective caring. The study found that workplace wellness initiatives are optimised when they are place-based and grounded in local knowledge, needs, and resources incorporating a collective and supportive team approach. Moreover, to ensure engagement in, and sustainability of these initiatives, both bottom-up and top-down commitment is required.

COVID-19 in non-healthcare workplace settings in NSW, Australia.

OBJECTIVES: To describe patterns of SARS-CoV-2 transmission in non-healthcare workplace settings during the first six months of COVID-19 spread, in New South Wales (NSW), Australia. METHODS: Locally acquired COVID-19 cases between February 2020 and August 2020 were reviewed to determine the: total number of workplace-associated cases and clusters; workplace type; and modes of transmission. RESULTS: There were 72 COVID-19 workplace clusters with 231 cases and an additional 11 workplace-acquired cases who were not part of a cluster. Workplaces most associated with clusters included construction, manufacture and trade (31%, 22 clusters), office and clerical (25%, 18 clusters) and retail (14%, 10 clusters). Most transmission events were best explained by direct transmission, with two workplace clusters demonstrating evidence of partial indirect spread. CONCLUSIONS: Findings demonstrate workplace settings, particularly construction, office and retail settings have heightened risk of transmission. IMPLICATIONS FOR PUBLIC HEALTH: The risk of infectious disease transmission is well understood for healthcare workers, despite other workplace types representing higher volumes of workers with less risk controls. This study should assist policy makers and the public to understand COVID-19 transmission in workplaces and the heightened risks associated with certain workplace settings.

COVID-19 in New South Wales children during 2021: severity and clinical spectrum.

OBJECTIVES: To describe the severity and clinical spectrum of coronavirus disease 2019 (COVID-19) in children during the 2021 New South Wales outbreak of the Delta variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). DESIGN, SETTING: Prospective cohort study in three metropolitan Sydney local health districts, 1 June - 31 October 2021. PARTICIPANTS: Children under 16 years of age with positive SARS-CoV-2 nucleic acid test results admitted to hospital or managed by the Sydney Children's Hospital Network (SCHN) virtual care team. MAIN OUTCOME MEASURES: Age-specific SARS-CoV-2 infection frequency, overall and separately for SCHN virtual and hospital patients; rates of medical and social reason admissions, intensive care admissions, and paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 per 100 SARS-CoV-2 infections; demographic and clinical factors that influenced likelihood of hospital admission. RESULTS: A total of 17 474 SARS-CoV-2 infections in children under 16 were recorded in NSW, of whom 11 985 (68.6%) received SCHN-coordinated care, including 459 admitted to SCHN hospitals: 165 for medical reasons (1.38 [95% CI, 1.17-1.59] per 100 infections), including 15 admitted to intensive care, and 294 (under 18 years of age) for social reasons (2.45 [95% CI, 2.18-2.73] per 100 infections). In an analysis that included all children admitted to hospital and a random sample of those managed by the virtual team, having another medical condition (adjusted odds ratio [aOR], 7.42; 95% CI, 3.08-19.3) was associated with increased likelihood of medical admission; in univariate analyses, non-asthmatic chronic respiratory disease was associated with greater (OR, 9.21; 95% CI, 1.61-174) and asthma/viral induced wheeze with lower likelihood of admission (OR, 0.38; 95% CI, 0.18-0.78). The likelihood of admission for medical reasons declined from infancy to 5-11 years, but rose again for those aged 12-15 years. Sex and Indigenous status did not influence the likelihood of admission. CONCLUSION: Most SARS-CoV-2 infections (Delta variant) in children were asymptomatic or associated with mild disease. Hospitalisation was relatively infrequent, and most common for infants, adolescents, and children with other medical conditions. More children were hospitalised for social than for medical reasons.

Reimagining consumer involvement: Resilient system indicators in the COVID-19 pandemic response in New South Wales, Australia.

BACKGROUND: Reflections on the response to the COVID-19 pandemic often evoke the concept of 'resilience' to describe the way health systems adjusted and adapted their functions to withstand the disturbance of a crisis, and in some cases, improve and transform in its wake. Drawing from this, this study focuses on the role of consumer representatives in healthcare services in initiating changes to the way they participated in the pandemic response in the state of New South Wales in Australia. METHODS: In-depth interviews were conducted with two cohorts of consumer representatives. Cohort A included experienced and self-identified consumer leaders, who worked together in a COVID-19 Consumer Leaders Taskforce; Cohort B included participants outside of this group, and purposively included consumer representatives from rural and regional areas, and culturally and linguistically diverse communities. RESULTS: The pause in consumer engagement to support health service decision-making in responding to the pandemic forced consumer representatives to consider alternative approaches to participate. Some initiated networking with each other, forming new collaborations to produce consumer-led research and guidelines on pandemic-related patient care. Others mobilized support from community and politicians to lobby for specific healthcare issues in their local areas. CONCLUSION: The response to the COVID-19 pandemic made visible the brittle nature of previous engagement processes of involving consumers in organizational design and governance. However, the momentum for proactive self-organization in an unexpected crisis created space for consumer representatives to reset and reimagine their role as active partners in health services. Their ability to adapt and adjust ways of working are key assets for a resilient health system. PATIENT OR PUBLIC CONTRIBUTION: This project is a collaborative study between academic researchers and health consumer (patient and public) representatives. It followed the principles of codesign and coresearch, whereby both consumer representatives and academic researchers contributed equally to all stages of the project. The study was cofunded by both academic institutions and consumer representative organizations.

Characteristics and co-admissions of mothers and babies admitted to residential parenting services in the year following birth in NSW: a linked population data study (2000-2012).

BACKGROUND: There is a tiered healthcare system in Australia to support maternal and child health, including, non-psychiatric day stay and residential parenting services (RPS) such as Tresillian and Karitane (in New South Wales [NSW]). RPS are unique to Australia, and currently there is limited information regarding the healthcare trajectory of women accessing RPS and if they are more likely to have admissions to other health facilities within the first-year post-birth. This study aimed to examine differences in hospital co-admissions for women and babies admitted to RPS in NSW in the year following birth compared to non-RPS admitted women. METHODS: A linked population data study of all women giving birth in NSW 2000-2012. Statistical differences were calculated using chi-square and student t-tests. RESULTS: Over the 12-year timeframe, 32,071 women and 33,035 babies were admitted to RPS, with 5191 of these women also having one or more hospital admissions (7607 admissions). The comparator group comprised of 99,242 women not admitted to RPS but having hospital admissions over the same timeframe (136,771 admissions). Statistically significant differences between cohorts were observed for the following parameters (p ≤ .001). Based upon calculated percentages, women who were admitted to RPS were more often older, Australian born, socially advantaged, private patients, and having their first baby. RPS admitted women also had more multiple births and labour and birth interventions (induction, instrumental birth, caesarean section, epidural, episiotomy). Their infants were also more often male and admitted to Special Care Nursery/Neonatal Intensive Care. Additionally, RPS admitted women had more admissions for mental health and behavioural disorders, which appeared to increase over time. There was no statistical difference between cohorts regarding the number of women admitted to a psychiatric facility; however, women attending RPS were more likely to have mood affective, or behavioural and personality disorder diagnoses. CONCLUSION: Women accessing RPS in the year post-birth were more socially advantaged, had higher birth intervention and more co-admissions and treatment for mental health disorders than those not accessing RPS. More research is needed into the impact of birth intervention and mental health issues on subsequent parenting difficulties.

Household transmission of COVID-19 in 2020 in New South Wales, Australia.

Households are high-risk settings for the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study examines factors associated with transmission among cases diagnosed with coronavirus disease 2019 (COVID-19) and their household contacts, in New South Wales (NSW), Australia, during July-October 2020. A register of all laboratory-confirmed COVID-19 cases was used to extract demographic and clinical information for cases and household contacts. Secondary attack rates (SARs) among household members were calculated and generalised estimating equations were used to estimate risks of transmission in relation to various characteristics of the primary case and the household contacts. In total, 229 households were included; they consisted of 229 primary cases and 659 close contacts. The overall household SAR was 22.5% (148/659). After adjusting for symptoms, age and sex of primary case, spouse status of household contacts and household size, the odds of secondary transmission were lower in primary cases who were asymptomatic at diagnosis than in symptomatic cases (odds ratio, OR: 0.13; 95% confidence interval (95% CI): 0.04-0.48); and higher in primary cases aged 60 years and over than in those aged 19-39 years (OR: 3.45; 95% CI: 1.53- 7.75). Being a spouse of the primary case was also associated with increased transmission compared to non-spouses (OR: 1.93; 95% CI: 1.24-3.02). After adjustments, there was no significant effect on transmission of the primary case's sex, or of the number of people in the household. This study documents demographic and clinical characteristics that increase transmission rates in households in the period prior to the introduction of SARS-CoV-2 variants. These data can be used as a baseline from which to compare household transmission in outbreaks dominated by new variants.