High SARS-CoV-2 attack rates in areas with low detection after community transmission established in Port Vila, Vanuatu, April 2022.

Objective: On 4 March 2022, the first community-acquired case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in Vanuatu, with community transmission occurring subsequently. It was expected that the number of notified SARS-CoV-2 cases would be an underestimate of the true infection rate of this outbreak; however, the magnitude of underreporting was unknown. The purpose of this study was to provide a population-based estimate of SARS-CoV-2 infection shortly after the first reports of community transmission, to understand the level of underdetection and undernotification in Vanuatu and thus to inform ongoing prevention and response activities. Methods: We conducted a cross-sectional SARS-CoV-2 prevalence study in two geographical administrative areas in Port Vila, Vanuatu in April 2022. All residents in selected areas were eligible. Trained teams conducted demographic and behavioural interviews and collected nasal specimens. Specimens were tested by polymerase chain reaction. The primary outcomes were the rates of SARS-CoV-2 attack (point prevalence) and cumulative attack, underdetection, notification and household secondary attack. Results: A total of 252 people from 84 households participated. Among 175 people who had a sample collected, 91 were SARS-CoV-2-positive (attack rate 52.0%). Most cases had not been detected before the study (underdetection rate 91.5%). More than half of previously detected cases were notified (notification rate 65.2%). Discussion: Within the first few weeks of community transmission, more than half of participants in the selected areas had evidence of SARS-CoV-2 infection; however, most infections had been undetected. This study provides important information about the rapid spread of novel infectious diseases in Vanuatu.

Fieldwork for public health responses during pandemics: lessons from the New South Wales Health experience with COVID-19.

Problem: Fieldwork is a vital component of public health emergency response, yet little has been published on undertaking fieldwork safely. Safety is of particular importance with emerging pandemic viruses, which can pose additional risks to public health fieldwork staff. Context: During a pandemic, surge health staff may be drawn from diverse professional backgrounds; they may have limited experience in fieldwork or be unfamiliar with the risks posed by a novel virus. Novel pathogens pose dangers to fieldwork staff, particularly when there are global or local shortages of personal protective equipment. Action: During the coronavirus disease 2019 (COVID-19) pandemic, New South Wales (NSW) Health's Public Health Emergency Operations Centre (PHEOC) deployed staff for fieldwork in a range of settings. The PHEOC developed a protocol to systematize planning, risk assessment and management for COVID-19 fieldwork. The protocol was accompanied by training, discussion exercises and debriefs to support PHEOC fieldwork staff. Lessons learned: Effective fieldwork is an essential component of outbreak investigation and management, including stakeholder management. Here, we share and discuss key elements of the NSW Health protocol to support fieldwork during outbreak responses for emerging communicable diseases across various resource contexts. Limited understanding of novel viruses, particularly in the early phases of a pandemic, must be considered in decisions to deploy fieldwork staff and implement precautionary risk mitigation approaches. Planning is essential to protect staff and ensure ethical allocation of resources. Through appropriate selection of teams and training, surge staff can be supported to effectively conduct fieldwork.

First reported outbreak of locally acquired hepatitis E virus infection in Australia.

OBJECTIVE: To determine the source and extent of a locally acquired hepatitis E virus (HEV) infection outbreak. DESIGN, SETTING AND PARTICIPANTS: A cluster of notified cases of HEV infection linked to a single restaurant (X) was identified in May 2014. People with laboratory-confirmed HEV infection in New South Wales between January 2013 and December 2014 were interviewed about potential risk factors for HEV infection. Co-diners at restaurant X and patients with suspected but unexplained viral hepatitis were retrospectively tested. Foods eaten by the infected persons were compared with those of seronegative co-diners. HEV RNA detected in sera from infected persons was sequenced and genotyped. Implicated foods were traced back to their sources. MAIN OUTCOME MEASURES: Potential sources of infection, including overseas travel and foods eaten, and origin of implicated food products. RESULTS: In 55 serologically confirmed cases of HEV infection, 24 people had not travelled overseas during their incubation periods. Of the 24, 17 reported having eaten at restaurant X, 15 of whom could be interviewed. All reported consuming pork liver pâté, compared with only four of seven uninfected co-diners (P < 0.05). The other seven people with locally acquired infections each reported consuming a pork product during their incubation periods. HEV RNA was detected in 16 of the 24 cases; all were of genotype 3. Sequencing indicated greater than 99% homology among restaurant X isolates. HEV RNA was isolated from pork sausages from a batch implicated in one of the locally acquired infections not linked with restaurant X. The pork livers used for pâté preparation by restaurant X were traced to a single Australian farm. CONCLUSIONS: This is the first reported HEV outbreak in Australia. HEV should be considered in patients presenting with a compatible illness, even without a history of overseas travel. Pork products should be thoroughly cooked before consumption.

What assay is optimal for the diagnosis of measles virus infection? An evaluation of the performance of a measles virus real-time reverse transcriptase PCR using the Cepheid SmartCycler(®) and antigen detection by immunofluorescence.

BACKGROUND: Despite the World Health Organization (WHO)-reported elimination of measles in Australia, importation of cases especially in travellers from Asia continues in Sydney, Australia's largest city. Laboratory confirmation supports clinico-epidemiological evidence of measles virus infection, and is needed to establish elimination. OBJECTIVES: To evaluate the performance of a random access real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay using the moderate complexity SmartCycler(®) platform, and measles antigen detection by immunofluorescence (IFA), for the detection of measles virus in patient samples. STUDY DESIGN: One hundred samples comprising nose and throat swabs, nasopharyngeal aspirates and urine, collected from patients with suspected measles were tested in parallel using IFA and nucleic acid testing using the SmartCycler(®) and LightCycler(®) RT-PCR platforms. The LightCycler(®) RT-PCR was used as the reference assay against which the SmartCycler(®) RT-PCR and IFA were compared. RESULTS: Using the LightCycler(®) RT-PCR, measles virus was detected in 35 clinical samples. There was 100% concordance between the results of the SmartCycler(®) and the LightCycler(®)-based RT-PCR. Measles genotypes detected included B3, D8, and D9. Testing urine in addition to NTS did not improve diagnostic yield. In contrast, the sensitivity and specificity of IFA compared to the reference LightCycler(®) RT-PCR was 34.3% and 96.7%, respectively. CONCLUSION: The performance of the SmartCycler(®) is comparable to the LightCycler(®) for the detection of measles virus. However, IFA had poor sensitivity and should not be used to confirm measles virus infection where nucleic acid testing is available.

The impact of stroke on unpaid caregivers: results from The Auckland Regional Community Stroke study, 2002-2003.

BACKGROUND: Few studies have assessed the longitudinal impact of providing unpaid care for stroke survivors. We aimed to describe the positive and negative impact of providing unpaid care and to identify independent predictors of poor carer outcome. METHODS: The Auckland Regional Community Stroke study was a prospective population-based stroke incidence study conducted in Auckland, New Zealand, over a 12-month period in 2002-2003. Stroke survivors and their unpaid carers were assessed at 6 and 18 months after stroke onset using the Short Form 36 questionnaire and the Bakas Caregiving Outcomes Scale. RESULTS: Data were available from 167 stroke survivor-carer pairs at 6 months and 62 pairs at 18 months. Unpaid carers reported lower health-related quality of life at 6 months after stroke than their age- and sex-matched counterparts in the New Zealand population. The impact of providing care was predominantly negative; however, approximately one third of the carers had improved relationships with the stroke survivor. No reliable predictors of carer burden were identified. CONCLUSIONS: This study re-emphasises the heavy burden of stroke on unpaid carers but was unable to identify factors that predicted carers at the greatest risk of experiencing a poor outcome. Effective strategies are needed to reduce the burden of providing unpaid care.

Frequency of depression after stroke: a systematic review of observational studies.

BACKGROUND AND PURPOSE: Although depression is an important sequelae of stroke, there is uncertainty regarding its frequency and outcome. METHODS: We undertook a systematic review of all published nonexperimental studies (to June 2004) with prospective consecutive patient recruitment and quantification of depressive symptoms/illness after stroke. RESULTS: Data were available from 51 studies (reported in 96 publications) conducted between 1977 and 2002. Although frequencies varied considerably across studies, the pooled estimate was 33% (95% confidence interval, 29% to 36%) of all stroke survivors experiencing depression. Differences in case mix and method of mood assessment could explain some of the variation in estimates across studies. The data also suggest that depression resolves spontaneously within several months of onset in the majority of stroke survivors, with few receiving any specific antidepressant therapy or active management. CONCLUSIONS: Depression is common among stroke patients, with the risks of occurrence being similar for the early, medium, and late stages of stroke recovery. There is a pressing need for further research to improve clinical practice in this area of stroke care.