Western Pacific Surveillance and Response最新文献

Objective: The COVID-19 pandemic disrupted disease surveillance systems globally, leading to reduced notifications of other infectious diseases. This study aims to estimate the impact of the COVID-19 pandemic on the infectious disease surveillance system in Klang district, Selangor state, Malaysia.

Methods: Data on notifiable diseases from 2014 to 2022 were sourced from the Klang District Health Office. The 11 diseases with more than 100 notifications each were included in the study. For these 11 diseases, a negative binomial regression model was used to explore the effect of the pandemic on case notifications and registrations by year, and a quasi-Poisson regression model was used to explore the changes by week.

Results: The results showed a reduction in the number of notifications and registrations for all 11 diseases combined during the pandemic compared with previous years. Changes between expected and observed notifications by week were heterogeneous across the diseases.

Discussion: These findings suggest that restrictive public health and social measures in Klang district may have impacted the transmission of other infectious diseases during the COVID-19 pandemic. The differential impact of the pandemic on disease notifications and reporting highlights the large ancillary effects of restrictive public health and social measures and the importance of building resilience into infectious disease surveillance systems.

Objective: Mortality surveillance was established in the state of Victoria just before the COVID-19 pandemic. Here, we describe the establishment of this surveillance system, justify the modelling approach selected, and provide examples of how the interpretation of changes in mortality rates during the pandemic was influenced by the model chosen.

Methods: Registered deaths occurring in Victoria from 1 January 2015 to 31 December 2020 were sourced from the Victoria Death Index. Observed mortality rates were compared to a raw historical 5-year mean and to predicted means estimated from a seasonal robust regression. Differences between the observed mortality rate and the historical mean (∆MR) and excess mortality rate from the observed and predicted rates were assessed.

Results: There were 20 375 COVID-19 cases notified in Victoria as of 31 December 2020, of whom 748 (3.7%) died. Victorians aged ≥ 85 years experienced the highest case fatality ratio (34%). Mean observed mortality rates in 2020 (MR: 11.6; 95% confidence interval [CI]: 11.4, 11.9) were slightly reduced when compared with the annual rate expected using the historical mean method (mean MR: 12.2; 95% CI: 12.1-12.3; ∆MR: -0.57; 95% CI: -0.77, -0.38), but not from the rate expected using the robust regression (estimated MR: 11.7; 95% prediction interval [PI]: 11.5, 11.9; EMR: -0.05; 95% CI: -0.26, 0.16). The two methods yielded opposing interpretations for some causes, including cardiovascular and cancer mortality.

Discussion: Interpretation of how pandemic restrictions impacted mortality in Victoria in 2020 is influenced by the method of estimation. Time-series approaches are preferential because they account for population trends in mortality over time.

Objective: We examined sociobehavioural factors associated with SARS-CoV-2 infection and estimated COVID-19 vaccine effectiveness against symptomatic SARS-CoV-2 infection in the Philippines. Such studies are limited in low- and middle-income countries, especially in Asia and the Pacific.

Methods: A case-control study was conducted in two hospitals in Manila, Philippines, from March 2022 to June 2023. Sociobehavioural factors and vaccination history were collected. PCR-positive individuals were cases, while PCR-negative individuals were controls. Adjusted odds ratios (aORs) were calculated to examine associations between sociobehavioural factors/vaccination and medically attended SARS-CoV-2 infection.

Results: The analysis included 2489 individuals (574 positive cases, 23.1%; 1915 controls, 76.9%; median age [interquartile range]: 35 [27-51] years). Although education and household income were not associated with infection, being a health-care worker was (aOR: 1.45; 95% confidence interval [CI]: 1.03-2.06). The odds of infection were higher among individuals who attended gatherings of five or more people compared to those who attended smaller gatherings (aOR: 2.58; 95% CI: 1.14-5.83). Absolute vaccine effectiveness for vaccination status was not estimated due to a high risk of bias, for example, unascertained prior infection. Moderate relative vaccine effectiveness for the first booster (32%; 95% CI: -120-79) and the second booster (48%; 95% CI: -23-78) were observed (both with wide CI), albeit with a waning trend after half a year.

Discussion: The higher odds of infection among health-care workers emphasize the importance of infection prevention and control measures. Moderate relative vaccine effectiveness with a waning trend reiterates the need for more efficacious vaccines against symptomatic infection caused by circulating variants and with longer duration of protection.

Objective: Cambodia is one of seven countries globally that met Millennium Development Goal 5A: reduction of maternal deaths by at least 75% between 1990 and 2015. The maternal death audit (MDA) was instituted in 2004 to support the improvement of maternal care. We evaluated progress in MDA implementation and maternal health services in Cambodia between 2010 and 2017.

Methods: International experts and the national MDA committee members assessed all case abstracts, investigation questionnaires and audit meeting minutes covering all maternal deaths reported in Cambodia in 2010 and 2017 for quality of classification, data, care and recommendations. They convened provincial MDA committees to conduct similar assessments and develop evidence-based recommendations. Differences in data from the two years were assessed for significance using χ² and Fisher's exact tests.

Results: In 2010 and 2017, 176 and 59 maternal death cases were reported, respectively. Cases were more likely in 2017 than in 2010 to have antenatal care (90.0% vs 68.2%, P = 0.004), give birth in a facility (81.6% vs 55.3%, P = 0.01) and receive a prophylactic uterotonic (95.7% vs 73%, P < 0.02) for postpartum haemorrhage and magnesium sulfate (66.7% vs 37%, P = 0.18) for preeclampsia/eclampsia. However, additional interventions and improved timeliness of referral with equipped and competent staff were identified as critical. Data quality prevented the classification of one fourth of cases during both periods. The quality of MDA recommendations improved from 2.8% in 2011 to 42% in 2018.

Discussion: Improvements in maternal care are reflected in the increased antenatal care, facility births and better postpartum haemorrhage and preeclampsia/eclampsia management. However, additional care management improvements are needed. The MDA reporting needs to improve data completeness and make more specific recommendations to address causes of death.

Problem: Over the past two decades, there has been increased recognition of the importance of a more holistic approach to preventing, predicting, detecting and responding to public health threats. The COVID-19 pandemic highlighted the need to bring together environmental, human and animal health sectors in addressing public health threats and the need to develop skilled front-line workers to act as surge capacity during health emergencies.

Context: Papua New Guinea is a high-risk country for emerging and re-emerging pathogens. The effects of climate change, human-mediated encroachment on natural habitats and destructive land-use practices have threatened ecosystems and caused environmental damage. The movement of goods, animals and people over porous borders provides opportunities for the introduction and spread of new pathogens.

Action: In recognition of the importance of multisectoral responses to health threats in Papua New Guinea, and the need to train front-line workers, we designed and piloted a 3-month One Health in-service training programme for front-line workers from across all sectors.

Lessons learned: The co-creation of curricula was essential in ensuring the relevance of the programme to front-line workers from multiple sectors, and the development of provincial training teams was key to ensuring mentorship and programme sustainability. Bringing front-line workers together in joint trainings facilitated the building of relationships, the understanding of the roles and responsibilities of the various sectors, the identification of sectoral focal points and the development of informal networks.

Discussion: Papua New Guinea's One Health front-line Field Epidemiology Training Program demonstrated that investment in cross-sectoral training programmes can be a catalyst for the implementation of One Health approaches on the front line.

Problem: The first known locally acquired cases of Japanese encephalitis virus (JEV) infection in New South Wales (NSW), Australia, were identified in March 2022. NSW Health (the state entity for health care in NSW), with its partner agencies, conducted a serological survey to identify the prevalence of JEV antibody responses in high-risk communities in NSW.

Context: JEV infection is rare in Australia; therefore, vaccination is not recommended for the majority of Australians. Less than 1% of JEV infections in humans result in clinical disease.

Action: We conducted a cross-sectional serological survey of all age groups in five townships within NSW between June and July 2022. A summary report of the serosurvey methods and results was previously published by NSW Health. In this report, we describe the operations and lessons learned from rapidly gathering serological survey evidence to inform the public health management of JEV infection in NSW, within a country with well established health infrastructure.

Lessons learned: Resource limitations had to be addressed pragmatically during this field epidemiology research. Community participation varied between towns. The knowledge of local public health staff was important for identifying appropriate locations for clinics and community engagement activities. The consistency of data collection needs to be emphasized when multiple teams are involved. Data quality assurance issues were limited during this survey, owing to ease of communication in the field with the coordinating research team. When possible, allowing additional time for community engagement and staff orientation would be beneficial before implementing a similar survey. Further consideration of reporting serology results during the study design stage might have prevented the need for manual processing upon study completion.

Discussion: This serological survey highlights that a well trained and coordinated public health workforce can provide important, timely evidence when faced with an emerging public health issue.

Objective: Due to rising cases of foodborne illness in Cayapa village, Abra province, Philippines, a team was dispatched on 21 March 2017 to conduct an epidemiological investigation. The objectives were to confirm the diagnosis, determine the existence of an outbreak, identify risk factors and recommend prevention and control measures.

Methods: A 1:2 case-control study was conducted. We defined a suspected case as a previously well village resident who developed abdominal pain or diarrhoea, and one or more symptoms of fever, vomiting, sore throat, difficulty swallowing or lymphadenopathy between 27 February and 14 March 2017. Confirmed cases were suspected cases who tested positive for Bacillus anthracis through bacterial culture or rt-PCR. Serum and soil samples were collected for testing, and an environmental survey and key informant interviews were conducted. Stata version 13 was used for data analysis.

Results: The epidemic curve indicated a point source outbreak for the 29 cases identified. Common signs and symptoms were abdominal pain (26, 90%), fever (16, 55%) and diarrhoea (14, 48%). One case presented with lymphadenopathy. Interviews revealed that a dead carabao had been butchered and sold to the villagers. The 11 serum specimens and five soil samples tested were negative for B. anthracis. After multivariable analysis, consumption of the uncooked meat of the carabao was significantly associated with being a case (adjusted odds ratio: 6, 95% CI: 1.7-18.4).

Discussion: This outbreak was most likely associated with the consumption of the carcass of a dead carabao. Educating such farming communities on preventive measures for zoonotic diseases is recommended.

Objective: In Viet Nam, tuberculosis (TB) prevalence surveys revealed that approximately 98% of individuals with pulmonary TB have TB-presumptive abnormalities on chest radiographs, while 32% have no TB symptoms. This prompted the adoption of the "Double X" strategy, which combines chest radiographs and computer-aided detection with GeneXpert testing to screen for and diagnose TB among vulnerable populations. The aim of this study was to describe demographic, clinical and radiographic characteristics of symptomatic and asymptomatic Double X participants and to assess multilabel radiographic abnormalities on chest radiographs, interpreted by computer-aided detection software, as a possible tool for detecting TB-presumptive abnormalities, particularly for subclinical TB.

Methods: Double X participants with TB-presumptive chest radiographs and/or TB symptoms and known risks were referred for confirmatory GeneXpert testing. The demographic and clinical characteristics of all Double X participants and the subset with confirmed TB were summarized. Univariate and multivariable logistic regression modelling was used to evaluate associations between participant characteristics and subclinical TB and between computer-aided detection multilabel radiographic abnormalities and TB.

Results: From 2020 to 2022, 96 631 participants received chest radiographs, with 67 881 (70.2%) reporting no TB symptoms. Among 1144 individuals with Xpert-confirmed TB, 51.0% were subclinical. Subclinical TB prevalence was higher in older age groups, non-smokers, those previously treated for TB and the northern region. Among 11 computer-aided detection multilabel radiographic abnormalities, fibrosis was associated with higher odds of subclinical TB.

Discussion: In Viet Nam, Double X community case finding detected pulmonary TB, including subclinical TB. Computer-aided detection software may have the potential to identify subclinical TB on chest radiographs by classifying multilabel radiographic abnormalities, but further research is needed.