COVID-19 in health care workers, Australia 2020.

BACKGROUND: Health care workers are at increased risk of SARS-CoV-2 infection due to potential exposure to patients or staff in health care settings. Australian health care services and health care workers experienced intense pressure to prepare for and respond to SARS-CoV-2 infections. We summarise national data on health care worker infections and associated outbreaks during 2020. METHODS: We collected aggregated data on infected health care workers and outbreaks in health care facilities from all jurisdictions. Health care workers working solely in residential aged care and outbreaks in residential aged care facilities were excluded. Jurisdictions provided data on the number of health care setting outbreaks, confirmed cases, hospitalisation, source of infection, and health care worker role. We analysed data for two periods that aligned with two distinct peaks in the epidemic relative to 1 June 2020, referred to here as the first wave (23 January - 31 May 2020) and the second wave (1 June - 18 September 2020). RESULTS: Jurisdictions reported a total of 2,163 health care worker infections with SARS-CoV-2 during the surveillance period. Source of acquisition was known for 81.0% of cases (1,667/2,059). The majority of cases in the first wave were acquired overseas, shifting to locally-acquired cases in the second wave. The odds of infection in the second wave compared to the first wave were higher for nurses/midwives (odds ratio, OR: 1.61; 95% confidence interval (95% CI): 1.32-2.00), lower for medical practitioners (OR: 0.36; 95% CI: 0.28-0.47) and did not differ for 'other' health care workers (OR: 1.07; 95% CI: 0. 87-1.32). The odds of infection in the second wave were higher in a health care setting (OR: 1.76; 95% CI: 1.28-2.41) than in the community. There were 120 outbreaks in health care settings with 1,428 cases, of which 56.7% (809/1,428) were health care workers. The majority (88/120; 73.8%) of outbreaks in health care settings occurred in the second wave of the epidemic, with 90.9% of these (80/88) occurring in Victoria. CONCLUSIONS: In the second wave of the epidemic, when there was heightened community transmission, health care workers were more likely to be infected in the workplace. Throughout the epidemic, nurses were more likely to be infected than staff in other roles.

An outbreak of serotype-1 sequence type 306 invasive pneumococcal disease in an Australian Indigenous population.

Between 2010 and 2013, an outbreak of serotype-1 sequence type 306 (ST306) invasive pneumococcal disease (IPD) occurred primarily in remote locations of Northern and Central Australia. This is a descriptive study of the epidemiology of the outbreak using nationwide IPD surveillance data, supplemented with more detailed data held by affected jurisdictions, and of the response to the outbreak, including vaccination strategies. In the year the outbreak peaked (2011), serotype-1 IPD incidence was over 30-fold higher in the affected regions than in the rest of Australia (incidence rate ratio: 30.7 [95% CI 20.1-48.9]). The study includes 245 cases of serotype-1 IPD from the outbreak regions, with 75.5% identified as Indigenous. No reported cases of serotype-1 IPD occurred in young children who had completed either a 10- or 13-valent pneumococcal conjugate vaccine schedule. However serotype-1 IPD did occur in older children who had previously received 23-valent pneumococcal polysaccharide vaccine. Development of public-health-focused national IPD management guidelines, including suitable vaccine strategies for consistent use nationwide, could potentially decrease the duration and intensity of similar outbreaks in the future.