ABSTRACT
Objectives: To compare serological evidence of prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with linked coronavirus disease 2019 (COVID-19) case notification data in Victoria, Australia, and to determine in vitro SARS-CoV-2 neutralisation activity based on prior infection and vaccination history. Design, setting, participants: Four cross-sectional serological surveys were conducted between 30 June and 31 October 2022 (a period of Omicron BA.4/BA.5 dominance) using 1,974 residual serum samples obtained from the Victorian Infectious Diseases Reference Laboratory. Serological results were linked to COVID-19 case notification and vaccination data. Surrogate virus neutralisation testing was performed to obtain in vitro inhibition estimates by anti-nucleocapsid serostatus and COVID-19 vaccination history. Main outcome measures: Adjusted anti-SARS-CoV-2 spike and nucleocapsid seropositivity by sex, age and region of residence; adjusted proportion of cases notified by anti-nucleocapsid serostatus, age and number of COVID-19 vaccination doses received; adjusted percentage in vitro inhibition against wildtype and Omicron BA.4/BA.5 SARS-CoV-2 variants by anti-nucleocapsid serostatus and COVID-19 vaccination history. Results: The prevalence of anti-SARS-CoV-2 nucleocapsid antibodies was inversely proportional to age. In October 2022, prevalence was 84% (95% confidence interval [95% CI]: 75-93%) among 18-29-year-olds, compared to 39% (95% CI: 27-52%) among ≥ 80-year-olds. In most age groups, approximately 40% of COVID-19 cases appear to have been notified via existing surveillance mechanisms. Case notification was highest among individuals older than 80 years and people who had received COVID-19 vaccine booster doses. In vitro neutralisation of Omicron BA.4/BA.5 sub-variants was highest for individuals with evidence of both prior infection and booster vaccination. Conclusions: Under-notification of SARS-CoV-2 infections in the Victorian population is not uniform across age and vaccination strata. Seroprevalence data that give insights into case notification behaviour provide additional context for the interpretation of existing COVID-19 surveillance information.
Subject(s)
Antibodies, Viral , COVID-19 Vaccines , COVID-19 , SARS-CoV-2 , Vaccination , Humans , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19/immunology , Male , Female , Victoria/epidemiology , Middle Aged , Adult , SARS-CoV-2/immunology , Aged , Adolescent , Young Adult , Antibodies, Viral/blood , COVID-19 Vaccines/immunology , COVID-19 Vaccines/administration & dosage , Cross-Sectional Studies , Seroepidemiologic Studies , Aged, 80 and over , Child , Child, Preschool , Age Factors , Infant , Antibodies, Neutralizing/bloodABSTRACT
Background: Regular repeat surveillance testing is a strategy to identify asymptomatic individuals with SARS-CoV-2 infections in high-risk work settings to prevent onward community transmission. Saliva sampling is less invasive compared to nasal/oropharyngeal sampling, thus making it suitable for regular testing. In this multi-centre evaluation, we aimed to validate RT-PCR using salivary swab testing of SARS-CoV-2 for large-scale surveillance testing and assess implementation amongst staff working in the hotel quarantine system in Victoria, Australia. Methods: A multi-centre laboratory evaluation study was conducted to systematically validate the in vitro and clinical performance of salivary swab RT-PCR for implementation of SARS-CoV-2 surveillance testing. Analytical sensitivity for multiple RT-PCR platforms was assessed using a dilution series of known SARS-CoV-2 viral loads, and assay specificity was examined using a panel of viral pathogens other than SARS-CoV-2. In addition, we tested capacity for large-scale saliva testing using a four-sample pooling approach, where positive pools were subsequently decoupled and retested. Regular, frequent self-collected saliva swab RT-PCR testing was implemented for staff across fourteen quarantine hotels. Samples were tested at three diagnostic laboratories validated in this study, and results were provided back to staff in real-time. Findings: The agreement of self-collected saliva swabs for RT-PCR was 84.5% (95% CI 68.6 to 93.8) compared to RT-PCR using nasal/oropharyngeal swab samples collected by a healthcare practitioner, when saliva samples were collected within seven days of symptom onset. Between 7th December 2020 and 17th December 2021, almost 500,000 RT-PCR tests were performed on saliva swabs self-collected by 102 staff working in quarantine hotels in Melbourne. Of these, 20 positive saliva swabs were produced by 13 staff (0.004%). The majority of staff that tested positive occurred during periods of community transmission of the SARS-CoV-2 Delta variant. Interpretation: Salivary RT-PCR had an acceptable level of agreement compared to standard nasal/oropharyngeal swab RT-PCR within early symptom onset. The scalability, tolerability and ease of self-collection highlights utility for frequent or repeated testing in high-risk settings, such as quarantine or healthcare environments where regular monitoring of staff is critical for public health, and protection of vulnerable populations. Funding: This work was funded by the Victorian Department of Health.
ABSTRACT
BACKGROUND: High testing rates and rapid contact tracing have been key interventions to control COVID-19 in Victoria, Australia. A mobile laboratory (LabVan), for rapid SARS-CoV-2 diagnostics, was deployed at sites deemed critical by the Victorian State Department of Health as part of the response. We describe the process of design, implementation, and performance benchmarked against a central reference laboratory. METHODS: A BSL2 compliant laboratory, complete with a class II biological safety cabinet, was built within a Mercedes-Benz Sprinter Panel Van. Swabs were collected by on-site collection teams, registered using mobile internet-enabled tablets and tested using the Xpert® Xpress SARS-CoV-2 assay. Results were reported remotely via HL7 messaging to Public Health Units. Patients with negative results were automatically notified by mobile telephone text messaging (SMS). FINDINGS: A pilot trial of the LabVan identified a median turnaround time (TAT) from collection to reporting of 1:19 h:mm (IQR 0:18, Range 1:03-18:32) compared to 9:40 h:mm (IQR 8:46, Range 6:51-19:30) for standard processing within the central laboratory. During deployment in nine rural and urban COVID-19 outbreaks the median TAT was 2:18 h:mm (IQR 1:18, Range 0:50-16:52) compared to 19:08 h:mm (IQR 5:49, Range 1:36-58:52) for samples submitted to the central laboratory. No quality control issues were identified in the LabVan. INTERPRETATION: The LabVan is an ISO15189 compliant testing facility fully operationalized for mobile point-of-care testing that significantly reduces TAT for result reporting, facilitating rapid public health actions. FUNDING: This work was supported by the Department of Health, Victoria State Government, Australia.
Subject(s)
COVID-19 , SARS-CoV-2 , Australia , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19 Testing , Humans , Point-of-Care Testing , Sensitivity and SpecificityABSTRACT
Personal response systems are used to support frail, older people, and people with disabilities to live independently in their own homes. This paper describes the patterns, characteristics, and outcomes of Personal Alert Victoria (PAV) clients who experience a fall. It also examines the current falls prevention referral practices of assessors who determine whether an older person would benefit from a personal response system. Deidentified data on clients from the PAV service provider from 2012 to 2014 were linked to routine data maintained by the Department of Health and Human Services in Victoria. Falls prevention referral practices of assessors were examined using an online survey. Personal response systems were most frequently activated because of a fall in this group of older people (n = 16,822; 44%). No demographic or clinical factors differentiated PAV clients who activated the system because of a fall compared to those who did not, despite a significant increase in the rate of falls-related system activations (p = 0.001) and hospitalisation (p < 0.001) between 2012 and 2014. Assessors believed that PAV clients were at increased risk of falls and frequently recommended falls prevention interventions such as strength and balance interventions (n = 112; 93%) in order to address this risk. This study has provided an insight into the issue of falls among PAV clients, which can help guide the tailoring of falls prevention interventions that can be integrated within existing service models.
ABSTRACT
This paper explores the perceptions and experiences of falls among Personal Alert Victoria (PAV) clients and identifies barriers and enablers to engagement in falls prevention interventions. Data were collected via semistructured telephone interviews (n = 12) and a client survey with open-ended and closed-ended questions (n = 46). Descriptive statistics and thematic analysis was guided by the COM-B model (capability, opportunity, and motivation) for behaviour change. The interview and survey explored experiences of falls, falls risk factors, access and participation in falls prevention interventions, access to health and support services, and experiences using the PAV service. Capability barriers identified included poor health, lack of time, low health literacy, and perceived high intensity of exercise classes. Opportunity barriers were lack of transport, high cost, and long waiting times for falls prevention interventions. Motivation barriers were the belief that falls are inevitable and a perceived lack of relevance of falls prevention interventions. Enablers identified were a focus on broader health and well-being benefits (capability), hospitalisations or rehabilitation that incorporates falls prevention in recovery (opportunity), and raising awareness of falls risk (motivation). Findings suggest that further research is required to inform the tailoring of positive health messages to improve the uptake of falls prevention interventions by PAV clients.
Subject(s)
Accidental Falls/prevention & control , Accidents, Home/prevention & control , Preventive Health Services/statistics & numerical data , Accident Prevention/methods , Community Health Services , Female , Humans , Motivation , Qualitative Research , Risk Assessment , Risk Factors , Surveys and QuestionnairesABSTRACT
As treatments and therapies develop and improve, enhancing life expectancy, Human Immunodeficiency Virus (HIV) has been described by some as a long term chronic condition rather than an acute life threatening illness. As this change occurs, new issues become relevant for the person living with HIV, employment being one of these. In light of this, the Positive Employment Service was developed and implemented to explore and address some of the issues related to employment for people living with HIV. The original concept for the service was primarily focused on vocational rehabilitation; however, it soon became clear that there was a need for a prevocational service facilitating transition and adjustment to productivity roles. The service was developed using approaches from Vocational and Occupational Therapy Models of Practice. This article discusses the challenges of developing and implementing this service and explores the unique perspective that occupational therapy brings to a position of this kind.