Communicable diseases intelligence (2018)最新文献

Abstract: We describe here the impact of managing coronavirus disease 2019 (COVID-19) outbreaks, during January-August 2022, in residential aged care facilities (RACFs) in Central Queensland, Australia, following the deployment of a public health rapid response team (PHRRT, comprising a medical officer, a communicable disease nurse, and an epidemiologist) from a regional public health unit (PHU). Our existing vaccine preventable diseases surveillance framework was used in identifying any symptomatic resident, triggering a PHRRT response. We found that the Hospital in the Home (HiTH) admission and death events were significantly lower after the introduction of the PHRRT than in the outbreaks that occurred before. Based on our experience with a PHRRT-led approach in mitigating the burden of outbreaks, we recommend regular reflection on optimising resources and practices in RACFs. Effective communication from PHUs can improve the RACFs' preparedness and capacity to respond, and can inform the best practice model to protect the highly susceptible elderly residents and their staff.

Abstract: During the SARS-CoV-2 Delta (B.1.617.2) variant outbreak, from August to October 2021 in the Australian Capital Territory (ACT), the number of new cases 'in the community for part of their infectious period' was publicly reported daily. We describe the stratification tool used during the outbreak to determine presumptive risk of community transmission from cases, and present the results of a contemporaneous validation of each case's risk against their onward transmission detected by routine surveillance. After case interview, epidemiologists identified the most likely source of infection for each new case and used the stratification tool to classify the case as either no, low, or high risk of community transmission. Each case notified between 12 August and 14 September 2021 was matched to its recipient case(s) to determine how well the tool predicted transmission risk. Household transmissions were excluded. Of the 530 notified cases stratified, 159 (29.3%) were cases who transmitted to a recipient case. Of the 59 cases who were the source of community transmission, 66% (38/59) were undertaking high-risk activities not associated with permitted essential work at the time. Only six source cases stratified as low risk or no risk transmitted SARS-CoV-2 to those outside their own household. The tool was essential in the rapid determination of community transmission risk in the ACT, and validation of the tool against detected onward transmission provided evidence for the effectiveness of public health restrictions. In the early stages of outbreaks of diseases for which transmissibility has not yet been established, the validation of such a stratification tool relies on high quality case investigation data, but may help to understand transmission dynamics and to inform interventions.

Abstract: The Northern Territory (NT) has the highest rates of sexually transmitted infections (STI) in Australia; however, the local prevalence of Mycoplasma genitalium (M. genitalium) has not been previously determined. This study was designed to review M. genitalium detection, to determine the regional NT prevalence and macrolide resistance rates. In our study the NT background prevalence of M. genitalium is 13%, with the highest detection rates occurring in central Australia and in correctional facility inmates. Symptomatic patients attending sexual health clinics have a positivity rate of 12%, but very high macrolide resistance. The decision to screen for M. genitalium should be based on several factors, including the prevalence of the infection in the local population; the availability of effective treatments; and the potential benefits and risks of detection and therapy.

Abstract: From 1 January 2020 to 31 December 2021, thirty-eight institutions across Australia submitted data to the Australian Group on Antimicrobial Resistance (AGAR) from patients aged < 18 years (AGAR-Kids). Over the two years, 1,679 isolates were reported from 1,611 patients. This AGAR-Kids report aims to describe the population of children and adolescents with bacteraemia reported to AGAR and the proportion of resistant isolates. Overall, there were 902 gram-negative isolates reported: 800 Enterobacterales, 61 Pseudomonas aeruginosa and 41 Acinetobacter spp. Among the Enterobacterales, 12.9% were resistant to third generation cephalosporins; 11.6% to gentamicin/tobramycin; and 11.2% to piperacillin-tazobactam. In total, 14.5% of Enterobacterales were multi-drug resistant (MDR). Only 3.3% of P. aeruginosa were resistant to carbapenems and 4.9% were MDR. Resistance in Acinetobacter spp was uncommon. Of 607 Staphylococcus aureus isolates, 12.9% were methicillin-resistant (MRSA). Almost half of S. aureus isolates from the Northern Territory were MRSA. In S. aureus, resistance to erythromycin was 13.2%; 12.4% to clindamycin; and 5.3% to ciprofloxacin. Resistance to all antibiotics tested was higher in MRSA. Overall, 6.5% of S. aureus were MDR, of which 65% were MRSA. Almost three-quarters of the 170 Enterococcus spp. reported were E. faecalis, and half were from patients < 1 year old. Ampicillin resistance in enterococci was 19.6%. Eight isolates were vancomycin resistant and three isolates were teicoplanin resistant. Five E. faecium isolates were classified as MDR. This AGAR-Kids report highlights clear differences in the geographic distribution of pathogens and resistance profiles across Australia.

Abstract: This study determined the hepatitis B e antigen (HBeAg) status of people living with chronic hepatitis B (CHB) in Far North Queensland (FNQ), Australia and their age of HBeAg loss. It was hoped that this would provide data to explain the stark difference in the incidence of hepatocellular carcinoma (HCC) between Aboriginal and Torres Strait Islander individuals living with CHB in FNQ, a finding that has been hypothesised to relate to differences in hepatitis B virus genotype. We identified every FNQ resident with CHB, determined their country of birth, their HBeAg status, the age they lost HBeAg and whether they identified as an Aboriginal, a Torres Strait Islander or a non-Indigenous individual. We then ascertained whether these demographic and virological variables were correlated. Of 1,474 individuals living with CHB in FNQ, 278 (19%) were Aboriginal, 507 (34%) were Torres Strait Islanders and 689 (47%) were non-Indigenous. Aboriginal individuals were less likely to be HBeAg positive (26/278, 9%) than Torres Strait Islander (91/507, 18%) and non-Indigenous (126/689, 18%) individuals, p < 0.0001. Aboriginal individuals lost HBeAg at an earlier age (median (interquartile range): 30 (23-39) years) than Torres Strait Islander (38 (29-49) years) and non-Indigenous (36 (29-47) years) individuals, p < 0.0001. Aboriginal individuals with CHB in FNQ are more likely to be HBeAg negative than Torres Strait Islander and non-Indigenous individuals and lose HBeAg at a younger age. This provides a biological basis for local clinicians' observation that Aboriginal individuals with CHB in FNQ are at a lower risk of HCC and data to support the principle of genotype-based care in the region.

Objective: Early in the coronavirus disease 2019 (COVID-19) pandemic, evidence emerged that individuals with chronic and immunocompromising conditions faced increased risk of severe infection, including death. The Australian Government and public health authorities prioritised these citizens' access to vaccines, including them in phase 1b of the rollout from 22 March 2021. Given the rapidly evolving knowledge and advice, we sought to understand what people with comorbidities understood about their eligibility, where they obtained information, and their experiences interfacing with the program.

Methods: Through the mixed methods project Coronavax, we conducted semi-structured in-depth interviews with eight West Australians aged under 60 who signed up to the study's webpage and declared comorbidities pertinent to serious COVID-19 complications. Interviews were conducted during January-April 2022, audio-recorded, transcribed in full, and analysed in NVivo 20 using inductive methods. We validated participants' accounts of state government actions with a representative in person and in writing.

Results: We identified access and informational barriers - and a lack of understanding - about vaccine eligibility amongst West Australians with comorbidities. Amid a rapidly changing landscape of knowledge with subsequent policy implications, this group received insufficient information for their needs for understanding their place in the immunisation program.

Conclusions: Fast-changing knowledge about vaccines creates communication challenges for government and health professionals. We identify an urgent need to develop, pilot, and evaluate strategies for providing vaccination information in routine and pandemic settings.

Abstract: Diphtheria is a potentially fatal bacterial infection caused by toxin-producing strains of corynebacteria, most often Corynebacterium diphtheriae and less commonly Corynebacterium ulcerans. Incidence of the disease has fallen significantly since the introduction of vaccination programs; it is now rare in countries with high vaccination coverage such as Australia. This article presents the most recent respiratory cases of diphtheria in two children in New South Wales-the first locally acquired childhood cases in Australia in 30 years-and discusses potential contributing factors. These encompass the lack of clinical awareness and the delays in laboratory diagnosis in regional laboratories. The cases also highlight the problem of vaccine hesitancy and the role that primary carers play in addressing these anxieties. While clinical management of the cases progressed well, factors in the public health responses were complicated by access to appropriate care and by delays in antibiotic sensitivity profiles. The public health response to these cases raises important considerations for clinicians and public health practitioners, including preparedness for rare and re-emerging diseases, the need for culturally safe environments and the importance of addressing vaccine hesitancy. Preparedness requires consideration of the capacity of regional health systems with fewer resources and of how public health departments can support response to multiple crises. Preparedness also relies on access to necessary diagnostic laboratory resources, on up-to-date guidelines, and on maintaining awareness among clinicians for these rare infections.

Introduction: Noroviruses are one of the most common causes of gastroenteritis in all age groups, including children. However, little has been reported on the transmission of norovirus within childcare facilities and the subsequent impact at the household level.

Methods: We conducted an outbreak investigation of norovirus gastroenteritis in Central Queensland, Australia during May 2021, in a childcare facility and the associated exposed households. Case definitions and outbreak management were employed as per the Communicable Disease Network Australia guidelines for norovirus and suspected viral gastroenteritis. Each case or carer and respective household member was interviewed to determine the date and time of symptom onset, health outcomes, and infector-infectee pairs. We estimated attack rates within the childcare facility and households, and basic reproductive number (R0) for norovirus using time-dependent methods.

Results: A total of 41 people developed gastrointestinal symptoms as a result of this outbreak, with 25 cases (61%) acquiring the infection in the centre and 16 cases (39%) occurring at households. Serial intervals were estimated as a mean 2.4 days (standard deviation 1.7 days), with a majority of cases (73%) in children under two years of age within the centre. Three faecal specimens were obtained, all detecting norovirus genotype II. The time-dependent R₀ was 1.5 (95% confidence interval [95% CI]: 1.0-2.2).

Discussion: The attack rate within the childcare facility was highest amongst children aged less than 2 years, highlighting the risk of infection for this age group. We recommend the exclusion of asymptomatic household contacts from childcare facilities to reduce the length and severity of norovirus outbreaks. Further investigation into childcare facility risk factors and associated households are required to optimise public health interventions.

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.

Abstract: In January 2023, an outbreak of Yersinia enterocolitica in residential aged care facilities (RACF) was identified by the Gold Coast Public Health Unit and confirmed using whole genome sequencing. During the outbreak period there were 11 confirmed and 14 probable cases of Y. enterocolitica notified in RACF and 30 suspected cases with compatible illness. Eleven cases (20%) were confirmed as Biotype 1A non-typable (BT1A NT) sequence type (ST) 278 within 4-15 single nucleotide polymorphisms (SNP) of each other. Combined epidemiological, trace-back and laboratory investigations identified nutritional milkshakes, stored at ideal growing conditions for Yersinia and given to vulnerable RACF residents, as the likely outbreak vehicle. This highlights that Y. enterocolitica Biotype 1A can be pathogenic in humans and transmission via atypical sources should be considered in outbreak investigations. This report outlines the response and challenges associated with investigating outbreaks in aged care.