Epidemiology of dengue reported in the World Health Organization's Western Pacific Region, 2013-2019.

The global burden of dengue, an emerging and re-emerging mosquito-borne disease, increased during the 20-year period ending in 2019, with approximately 70% of cases estimated to have been in Asia. This report describes the epidemiology of dengue in the World Health Organization's Western Pacific Region during 2013-2019 using regional surveillance data reported from indicator-based surveillance systems from countries and areas in the Region, supplemented by publicly available dengue outbreak situation reports. The total reported annual number of dengue cases in the Region increased from 430 023 in 2013 to 1 050 285 in 2019, surpassing 1 million cases for the first time in 2019. The reported case-fatality ratio ranged from 0.19% (724/376 972 in 2014 and 2030/1 050 285 in 2019) to 0.30% (1380/458 843 in 2016). The introduction or reintroduction of serotypes to specific areas caused several outbreaks and rare occurrences of local transmission in places where dengue was not previously reported. This report reinforces the increased importance of dengue surveillance systems in monitoring dengue across the Region.

First human infection of avian influenza A(H5N6) virus reported in Lao People's Democratic Republic, February-March 2021.

In March 2021, Lao People's Democratic Republic (Laos) reported an avian influenza A(H5N6) virus infection in a 5-year-old child identified through sentinel surveillance. This was the first human A(H5N6) infection reported outside of China. A multidisciplinary investigation undertook contact tracing and enhanced human and animal surveillance in surrounding villages and live bird markets. Seven Muscovy ducks tested positive for highly pathogenic avian influenza A(H5N6) viruses. Sequenced viruses belonged to clade 2.3.4.4h and were closely related to viruses detected in poultry in Vietnam and to previous viruses detected in Laos. Surveillance and coordinated outbreak response remain essential to global health security.

An epidemiological overview of human infections with HxNy avian influenza in the Western Pacific Region, 2003-2022.

Avian influenza subtype A(HxNy) viruses are zoonotic and may occasionally infect humans through direct or indirect contact, resulting in mild to severe illness and death. Member States in the Western Pacific Region (WPR) communicate and notify the World Health Organization of any human cases of A(HxNy) through the International Health Regulations (IHR 2005) mechanism. This report includes all notifications in the WPR with illness onset dates from 1 November 2003 to 31 July 2022. During this period, there were 1972 human infections with nine different A(HxNy) subtypes notified in the WPR. Since the last report, an additional 134 human avian influenza infections were notified from 1 October 2017 to 31 July 2022. In recent years there has been a change in the primary subtypes and frequency of reports of human A(HxNy) in the region, with a reduction of A(H7N9) and A(H5N1), and conversely an increase of A(H5N6) and A(H9N2). Furthermore, three new subtypes A(H7N4), A(H10N3) and A(H3N8) notified from the People's Republic of China were the first ever recorded globally. The public health risk from known A(HxNy) viruses remains low as there is no evidence of person-to-person transmission. However, the observed changes in A(HxNy) trends reinforce the need for effective and rapid identification to mitigate the threat of a pandemic from avian influenza if person-to-person transmission were to occur.

Estimating the national burden of hospitalizations for influenza-associated severe acute respiratory infection in the Lao People's Democratic Republic, 2016.

OBJECTIVE: Estimates of the burden of influenza are needed to inform prevention and control activities for seasonal influenza, including to support the development of appropriate vaccination policies. We used sentinel surveillance data on severe acute respiratory infection (SARI) to estimate the burden of influenza-associated hospitalizations in the Lao People's Democratic Republic. METHODS: Using methods developed by the World Health Organization, we combined data from hospital logbook reviews with epidemiological and virological data from influenza surveillance from 1 January to 31 December 2016 in defined catchment areas for two sentinel sites (Champasack and Luang Prabang provincial hospitals) to derive population-based estimates of influenza-associated SARI hospitalization rates. Hospitalization rates by age group were then applied to national age-specific population estimates using 2015 census data. RESULTS: We estimated the overall influenza-associated SARI hospitalization rate to be 48/100 000 population (95% confidence interval [CI]: 44-51) or 3097 admissions (95% CI: 2881-3313). SARI hospitalization rates were estimated to be as low as 40/100 000 population (95% CI: 37-43) and as high as 92/100 000 population (95% CI: 87-98) after accounting for SARI patient underascertainment in hospital logbooks. Influenza-associated SARI hospitalization rates were highest in children aged < 5 years (219; 95% CI: 198-241) and persons aged 3 65 years (106; 95% CI: 91-121). DISCUSSION: Our findings have identified age groups at higher risk for influenza-associated SARI hospitalization, which will support policy decisions for influenza prevention and control strategies, including for vaccination. Further work is needed to estimate the burdens of outpatient influenza and influenza in specific high-risk subpopulations.

Regional event-based surveillance in WHO's Western Pacific Region.

In the World Health Organization's Western Pacific Region, event-based surveillance has been conducted for more than a decade to rapidly detect and assess public health events. This report describes the establishment and evolution of the Western Pacific Region's event-based surveillance system and presents an analysis of public health events in the Region. Between July 2008 and June 2017, a total of 2396 events were reported in the Western Pacific Region, an average of 266 events per year. Infectious diseases in humans and animals accounted for the largest proportion of events recorded during this period (73%, 1743 events). Maintaining and strengthening this well established system is critical to support the rapid detection, assessment and response to public health events to sustain regional health security.

The changing epidemiology of measles in an era of elimination: lessons from health-care-setting transmissions of measles during an outbreak in New South Wales, Australia, 2012.

INTRODUCTION: In countries where measles is rare, health-care-setting transmissions remain problematic. Australia experienced its largest measles outbreak in 15 years in 2012 with 199 cases reported nationally; 170 cases occurred in the state of New South Wales (NSW) with symptom onset between 7 April and 29 November 2012. METHODS: A descriptive study was conducted using measles case data obtained from metropolitan Sydney local health districts in NSW in 2012. Characteristics of measles source and secondary cases were described. Details of health-care presentations resulting and not resulting in measles transmission were also analysed. RESULTS: There were 168 confirmed and two probable cases resulting in 405 documented health-care presentations. Thirty-four secondary cases acquired in health-care settings were identified, including 29 cases resulting from 14 source cases and 5 cases whose source could not be identified. Health-care-acquired cases accounted for 20% of all cases in this outbreak. Source cases were more likely to be of Pacific Islander descent (P = 0.009) and to have had more presentations before diagnosis (P = 0.012) compared to other cases. The percentage of presentations to emergency departments was higher for presentations that resulted in transmission compared to those that did not (71.4% and 37.6%, respectively, P = 0.028). There were no significant differences between transmission and non-transmission presentations with respect to presence of rash and infection control measures (P = 0.762 and P = 0.221, respectively), although the power to detect these differences was limited. Rash was reported at 66% of the presentations. CONCLUSION: Development of and adherence to protocols for the management of patients presenting to hospitals with fever and rash will minimize secondary transmission of measles.

Epidemiological update on the dengue situation in the Western Pacific Region, 2012.

Dengue has caused a substantial public health burden in the Western Pacific Region. To assess this burden and regional trends, data were collated and summarized from indicator-based surveillance systems on dengue cases and deaths from countries and areas in the Western Pacific Region. In 2012, dengue notifications continued to increase with 356,838 dengue cases reported in the Region (relative to 244,855 cases reported in 2011) of which 1248 died. In the Asia subregion, the notification rate was highest in Cambodia, the Philippines and the Lao People's Democratic Republic (316.2, 198.9 and 162.4 per 100,000 population, respectively), and in the Pacific island countries and areas, the notification rate was highest in Niue, the Marshall Islands and the Federated States of Micronesia (8556.0, 337.0 and 265.1 per 100,000 population, respectively). All four serotypes were circulating in the Region in 2012 with considerable variabilitiy in distribution. Regional surveillance provides important information to enhance situational awareness, conduct risk assessments and improve preparedness activities.

Australian vaccine preventable disease epidemiological review series: measles 2000-2011.

BACKGROUND: Since the introduction of measles vaccine to the vaccination schedule, the burden of measles has substantially fallen in Australia. Despite this, a number of recent measles outbreaks have occurred. The aim of this study was to examine the burden of measles in Australia using notification, hospitalisation and mortality data with the objectives of setting a baseline for comparison prior to the introduction of the combined measles-mumps-rubella-varicella vaccine. METHODS: Data were obtained from the Australian National Notifiable Diseases Surveillance System, the National Hospital Morbidity Database and the National Mortality Database to obtain notification, hospitalisation and death data, respectively from 2000 to 2011. Rates were calculated and compared over time by age group and jurisdiction. RESULTS: Since 1993, measles notifications have fallen considerably in Australia. However, between 2000 and 2011, measles notification rates and hospitalisation rates fluctuated. Between 2000 and 2011, there were 990 measles notifications in Australia. The average annual notification rate was 0.4 per 100,000 population. Children aged 0-4 years were the most susceptible group, particularly infants less than 1 year of age (average annual rate, 1.6 per 100,000 population). High incidence was also observed in adolescents (average annual rate, 0.7 per 100,000 population) and young adults (average annual rate, 0.8 per 100,000 population). Jurisdictional variation occurred with differing patterns of notifications and hospitalisations. CONCLUSIONS: Although a marked reduction in measles notifications and hospitalisations has occurred in the past decade, susceptible individuals should be vaccinated to prevent outbreaks and to maintain a low incidence of measles and Australia's elimination status.

Sex matters – a preliminary analysis of Middle East respiratory syndrome in the Republic of Korea, 2015

Convincing evidence suggests that females and males are different in regard to susceptibility to both infectious and non-infectious diseases. Sex and gender influences the severity and outcome of several infectious diseases, including leptospirosis, tuberculosis, listeriosis, Q fever, avian influenza and SARS.

Epidemiological update on the dengue situation in the Western Pacific Region, 2012

Dengue has caused a substantial public health burden in the Western Pacific Region. To assess this burden and regional trends, data were collated and summarized from indicator-based surveillance systems on dengue cases and deaths from countries and areas in the Western Pacific Region. In 2012, dengue notifications continued to increase with 356 838 dengue cases reported in the Region (relative to 244 855 cases reported in 2011) of which 1248 died. In the Asia subregion, the notification rate was highest in Cambodia, the Philippines and the Lao People's Democratic Republic (316.2, 198.9 and 162.4 per 100 000 population, respectively), and in the Pacific island countries and areas, the notification rate was highest in Niue, the Marshall Islands and the Federated States of Micronesia (8556.0, 337.0 and 265.1 per 100 000 population, respectively). All four serotypes were circulating in the Region in 2012 with considerable variabilitiy in distribution. Regional surveillance provides important information to enhance situational awareness, conduct risk assessments and improve preparedness activities.

Cancer Screening among immigrants living in urban and regional Australia: results from the 45 and up study.

Over 25% of the Australian population are immigrants, and are less active participants in cancer screening programmes. Most immigrants live in urban areas of Australia, but a significant proportion (~20%), live in regional areas. This study explored differences in cancer screening participation by place of birth and residence. Self-reported use of mammogram, faecal occult blood test (FOBT), and/or prostate specific antigen (PSA) tests was obtained from 48,642 immigrants and 141,275 Australian-born participants aged 50 years or older in the 45 and Up Study (New South Wales, Australia 2006-2010). Poisson regression was used to estimate relative risks of test use, adjusting for key socio-demographic characteristics. Overall, immigrants from Asia and Europe were less likely to have had any of the tests in the previous two years than Australian-born participants. Regional Australian-born participants were more likely to have had any of the tests than those living in urban areas. Regional immigrant participants were more likely to have had an FOBT or PSA test than those living in urban areas, but there were no differences in mammograms. This report identifies key immigrant groups in urban and regional areas that policymakers and healthcare providers should target with culturally appropriate information to promote cancer screening.

Estimating the measles effective reproduction number in Australia from routine notification data.

OBJECTIVE: To estimate the measles effective reproduction number (R) in Australia by modelling routinely collected notification data. METHODS: R was estimated for 2009-2011 by means of three methods, using data from Australia's National Notifiable Disease Surveillance System. Method 1 estimated R as 1 - P, where P equals the proportion of cases that were imported, as determined from data on place of acquisition. The other methods estimated R by fitting a subcritical branching process that modelled the spread of an infection with a given R to the observed distributions of outbreak sizes (method 2) and generations of spread (method 3). Stata version 12 was used for method 2 and Matlab version R2012 was used for method 3. For all methods, calculation of 95% confidence intervals (CIs) was performed using a normal approximation based on estimated standard errors. FINDINGS: During 2009-2011, 367 notifiable measles cases occurred in Australia (mean annual rate: 5.5 cases per million population). Data were 100% complete for importation status but 77% complete for outbreak reference number. R was estimated as < 1 for all years and data types, with values of 0.65 (95% CI: 0.60-0.70) obtained by method 1, 0.64 (95% CI: 0.56-0.72) by method 2 and 0.47 (95% CI: 0.38-0.57) by method 3. CONCLUSION: The fact that consistent estimates of R were obtained from all three methods enhances confidence in the validity of these methods for determining R.

Cancer incidence and mortality in people aged less than 75 years: changes in Australia over the period 1987-2007.

BACKGROUND: Australia has one of the highest rates of cancer incidence worldwide and, despite improving survival, cancer continues to be a major public health problem. Our aim was to provide simple summary measures of changes in cancer mortality and incidence in Australia so that progress and areas for improvement in cancer control can be identified. METHODS: We used national data on cancer deaths and newly registered cancer cases and compared expected and observed numbers of deaths and cases diagnosed in 2007. The expected numbers were obtained by applying 1987 age-sex specific rates (average of 1986-1988) directly to the 2007 population. The observed numbers of deaths and incident cases were calculated for 2007 (average of 2006-2008). We limited the analyses to people aged less than 75 years. RESULTS: There was a 28% fall in cancer mortality (7827 fewer deaths in 2007 vs. 1987) and a 21% increase in new cancer diagnoses (13,012 more diagnosed cases in 2007). The greatest reductions in deaths were for cancers of the lung in males (-2259), bowel (-1797), breast (-773) and stomach (-577). Other notable falls were for cancers of the prostate (-295), cervix (-242) and non-Hodgkin lymphoma (-240). Only small or no changes occurred in mortality for cancers of the lung (female only), pancreas, brain and related, oesophagus and thyroid, with an increase in liver cancer (267). Cancer types that showed the greatest increase in incident cases were cancers of the prostate (10,245), breast (2736), other cancers (1353), melanoma (1138) and thyroid (1107), while falls were seen for cancers of the lung (-1705), bladder (-1110) and unknown primary (-904). CONCLUSIONS: The reduction in mortality indicates that prevention strategies, improvements in cancer treatment, and screening programmes have made significant contributions to cancer control in Australia since 1987. The rise in incidence is partly due to diagnoses being brought forward by technological improvements and increased coverage of screening and early diagnostic testing.

An outbreak of staphylococcal food poisoning in a commercially catered buffet.

Staphylococcal food poisoning is a common cause of foodborne illness. In Australia, since 2000, approximately 30% of foodborne Staphylococcus aureus outbreaks reported to OzFoodNet have been associated with foods prepared by commercial caterers. We conducted a retrospective cohort analysis of an outbreak of gastrointestinal illness among participants of an elite sporting event during which 22 individuals became ill after eating a commercially catered buffet dinner in June 2012. All recalled eating fried rice which had been intended for lunch service earlier that day and 20 of the 22 reported eating chicken stir-fry. Though no food samples were available for analysis, laboratory analysis conducted on four faecal specimens resulted in S. aureus being cultured from one specimen and S. aureus enterotoxin detected in another. The known epidemiology of staphylococcal food poisoning suggests a food contaminated by an infected food handler which was subject to temperature abuse may have caused the outbreak. As S. aureus foodborne outbreaks are often underreported, this investigation is a valuable contribution to the evidence-base and understanding of foodborne illness due to S. aureus and staphylococcal enterotoxin.

A cross-sectional exploration of smoking status and social interaction in a large population-based Australian cohort.

We used cross-sectional data to investigate whether current, past and never smokers report different levels of social interaction and whether the level of social interaction varied according to the type of interaction being measured. Self-reported questionnaire data were obtained from 239,043 men and women aged 45 years or older living in Australia between February 2006 and February 2010. The study participation rate was 18%. Poisson regression models were used to estimate the percentage differences in the mean values of four social interaction outcomes according to smoking status after adjusting for age, place of residence, income, education, health insurance status, physical limitation, psychological distress and exposure to passive smoke: number of times 1) spent with friends/family, 2) spoken on the telephone, 3) attended social meetings in the past week, and 4) number of people outside of home that can be depended upon. 7.6% of males and 6.9% of females were current smokers, 43.6% of males and 28.6% of females were ex-smokers and 48.8% of males and 64.5% of females had never smoked. Compared to never smokers, current smokers reported significantly fewer social interactions in the past week and had fewer people outside the home that they could depend on. Men and women current smokers attended 24.0% (95% CI, 20.3, 27.5) and 31.1% (95% CI, 28.1, 34.1) fewer social group meetings on average than never smokers. Smokers exposed to passive smoke reported higher levels of social interaction than those not exposed. Past smokers reported levels of social interaction that were intermediate to those of current and never smokers and the more years they had abstained from smoking, the more social interaction they reported on average. Our data are in line with previous research showing that smokers are not only worse off economically, physically and mentally, but are also less likely to be socially connected.