Imported malaria into Australia: surveillance insights and opportunities

BACKGROUND

Malaria continues to pose a significant burden in endemic countries, many of which lack access to molecular surveillance. Insights from malaria cases in travellers returning to non-endemic areas can provide valuable data to inform endemic country programmes. To evaluate the potential for novel global insights into malaria, we examined epidemiological and molecular data from imported malaria cases to Australia.

METHODS

We analysed malaria cases reported in Australia from 2012 to 2022 using National Notifiable Disease Surveillance System data. Molecular data on imported malaria cases were obtained from literature searches.

RESULTS

Between 2012 and 2022, 3204 malaria cases were reported in Australia. Most cases (69%) were male and 44% occurred in young adults aged 20-39 years. Incidence rates initially declined between 2012 and 2015, then increased until 2019. During 2012-2019, the incidence in travellers ranged from 1.34 to 7.71 per 100 000 trips. Cases were primarily acquired in Sub-Saharan Africa (n = 1433; 45%), Oceania (n = 569; 18%) and Southern and Central Asia (n = 367; 12%). The most common countries of acquisition were Papua New Guinea (n = 474) and India (n = 277). Plasmodium falciparum accounted for 58% (1871/3204) of cases and was predominantly acquired in Sub-Saharan Africa, and Plasmodium vivax accounted for 32% (1016/3204), predominantly from Oceania and Asia. Molecular studies of imported malaria cases to Australia identified genetic mutations and deletions associated with drug resistance and false-negative rapid diagnostic test results, and led to the establishment of reference genomes for P. vivax and Plasmodium malariae.

CONCLUSIONS

Our analysis highlights the continuing burden of imported malaria into Australia. Molecular studies have offered valuable insights into drug resistance and diagnostic limitations, and established reference genomes. Integrating molecular data into national surveillance systems could provide important infectious disease intelligence to optimize treatment guidelines for returning travellers and support endemic country surveillance programmes.

The epidemiology of imported and locally acquired dengue in Australia, 2012-2022

BACKGROUND

Dengue is the most important arboviral disease globally and poses ongoing challenges for control including in non-endemic countries with competent mosquito vectors at risk of local transmission through imported cases. We examined recent epidemiological trends in imported and locally acquired dengue in Australia, where the Wolbachia mosquito population replacement method was implemented throughout dengue-prone areas of northern Queensland between 2011 and 2019.

METHODS

We analysed dengue cases reported to the Australian National Notifiable Disease Surveillance System between January 2012 and December 2022, and Australian traveller movement data.

RESULTS

Between 2012 and 2022, 13 343 dengue cases were reported in Australia (median 1466 annual cases); 12 568 cases (94.2%) were imported, 584 (4.4%) were locally acquired and 191 (1.4%) had no origin recorded. Locally acquired cases decreased from a peak in 2013 (n = 236) to zero in 2021-22. Annual incidence of imported dengue ranged from 8.29/100 000 (n = 917 cases) to 22.10/100 000 (n = 2203) annual traveller movements between 2012 and 2019, decreased in 2020 (6.74/100 000 traveller movements; n = 191) and 2021 (3.32/100 000 traveller movements; n = 10) during COVID-19-related border closures, then rose to 34.79/100 000 traveller movements (n = 504) in 2022. Imported cases were primarily acquired in Southeast Asia (n = 9323; 74%), Southern and Central Asia (n = 1555; 12%) and Oceania (n = 1341; 11%). Indonesia (n = 5778; 46%) and Thailand (n = 1483; 12%) were top acquisition countries. DENV-2 (n = 2147; 42%) and DENV-1 (n = 1526; 30%) were predominant serotypes.

CONCLUSION

Our analysis highlights Australia's successful control of locally acquired dengue with Wolbachia. Imported dengue trends reflect both Australian travel destinations and patterns and local epidemiology in endemic countries.

Text mining analysis to understand the impact of online news on public health response: case of syphilis epidemic in Brazil

Background

To effectively combat the rising incidence of syphilis, the Brazilian Ministry of Health (MoH) created a National Rapid Response to Syphilis with actions aimed at bolstering epidemiological surveillance of acquired, congenital syphilis, and syphilis during pregnancy complemented with communication activities to raise population awareness and to increase uptake of testing that targeted mass media outlets from November 2018 to March 2019 throughout Brazil, and mainly areas with high rates of syphilis. This study analyzes the volume and quality of online news content on syphilis in Brazil between 2015 and 2019 and examines its effect on testing.

Methods

The collection and processing of online news were automated by means of a proprietary digital health ecosystem established for the study. We applied text data mining techniques to online news to extract patterns from categories of text. The presence and combination of such categories in collected texts determined the quality of news that were analyzed to classify them as high-, medium-and low-quality news. We examined the correlation between the quality of news and the volume of syphilis testing using Spearman's Rank Correlation Coefficient.

Results

1,049 web pages were collected using a Google Search API, of which 630 were categorized as earned media. We observed a steady increase in the number of news on syphilis in 2015 (n = 18), 2016 (n = 26), and 2017 (n = 42), with a substantial rise in the number of news in 2018 (n = 107) and 2019 (n = 437), although the relative proportion of high-quality news remained consistently high (77.6 and 70.5% respectively) and in line with similar years. We found a correlation between news quality and syphilis testing performed in primary health care with an increase of 82.32, 78.13, and 73.20%, respectively, in the three types of treponemal tests used to confirm an infection.

Conclusion

Effective communication strategies that lead to dissemination of high quality of information are important to increase uptake of public health policy actions.

An outbreak of acute rheumatic fever in a remote Aboriginal community

OBJECTIVES

We describe the public health response to an outbreak of acute rheumatic fever (ARF) in a remote Aboriginal community.

METHODS

In August 2021, the Northern Territory Rheumatic Heart Disease Control Program identified an outbreak of acute rheumatic fever in a remote Aboriginal community. A public health response was developed using a modified acute poststreptococcal glomerulonephritis protocol and the National Acute Rheumatic Fever Guideline for Public Health Units.

RESULTS

12 cases were diagnosed during the outbreak; six-times the average number of cases in the same period in the five years prior (n=1.8). Half (n=6) of the outbreak cases were classified as recurrent episodes with overdue secondary prophylaxis. Contact tracing and screening of 11 households identified 86 close contacts.

CONCLUSIONS

This outbreak represented an increase in both first episodes and recurrences of acute rheumatic fever and highlights the critical need for strengthened delivery of acute rheumatic fever secondary prophylaxis, and for improvements to the social determinants of health in the region.

IMPLICATIONS FOR PUBLIC HEALTH

Outbreaks of acute rheumatic fever are rare despite continuing high rates of acute rheumatic fever experienced by remote Aboriginal communities. Nevertheless, there can be improvements in the current national public health guidance relating to acute rheumatic fever cluster and outbreak management.

An evaluation of the notifiable disease surveillance system in Chegutu District, Zimbabwe, 2020: a cross-sectional study

Introduction

in 2018-2019 Chegutu District had one notification form Tally 1 (T1) that was completed instead of seven for detected notifiable diseases. Different figures of cholera were reported through weekly rapid disease notification system with 106 patients and Notifiable Diseases Surveillance System (NDSS) with 111 patients, causing data discrepancy. We evaluated the NDSS to determine reasons for underperformance and data discrepancy.

Methods

we conducted descriptive cross-sectional study using updated centres for disease control and prevention guidelines for surveillance system evaluation. We recruited forty-six health workers. Interviewer-administered questionnaires and checklists were used to collect data on reasons for underperformance, reasons for data discrepancy, knowledge of NDSS, surveillance system attributes and usefulness. Epi InfoTM7 generated frequencies, proportions, and means. Likert scale was used to assess health worker knowledge.

Results

of the forty-six health workers, 34 (78%) had fair knowledge of NDSS. The reason for system underperformance was lack of training in NDSS 42 (91%). Data discrepancy was attributed to typographical mistakes made during data entry on WhatsApp platform 32 (70%). Eighty per cent (37) were willing to complete T1 forms. Six participants who were timed took ten minutes to complete T1 forms. Among 17 health facilities, only three had fifteen T1 forms that were adequate to notify first five cases in an outbreak. Notifiable diseases surveillance system data was used for planning health education 28 (68%).

Conclusion

the NDSS was unstable due to health workers' inadequate knowledge and unavailability of T1 forms. Notifiable diseases surveillance system was found to be simple, acceptable, and useful. We recommended NDSS training of health workers.

Use of Interrupted Time Series Analysis in Understanding the Course of the Congenital Syphilis Epidemic in Brazil

Background

To fight against the rising incidence of syphilis, the Brazilian Ministry of Health (MoH) launched the "Syphilis No!" Project (SNP), with specific resources funded by a parliamentary amendment. Then, in 2018, a national rapid response started to be implemented on the Brazilian Unified Health System (SUS, Sistema Único de Saúde) in two strategic lines (1) to reinforce SUS's universal actions and (2) to implement specific ones to 100 municipalities chosen by the MoH as priorities for syphilis congenital response. In 2015, such localities represented 6895% of congenital syphilis cases in Brazil. In this context, SNP has implemented actions to strengthen epidemiological surveillance of acquired syphilis and congenital syphilis by instituting an integrated and collaborative response through health services networks and reinforcing interstate relations.

Methods

A quasi-experimental study using time series analysis was conducted to assess immediate impacts and changes to the trend in national congenital syphilis before and after the project, from September 2016 to December 2019. Data were assessed considering rates of congenital syphilis per 1,000 live births in all priority municipalities (n=100) covered by the project and in non-priority municipalities (n=5,470) from all five macro-regions of Brazil.

Findings

Priority municipalities showed a greater reduction (change in trend) in comparison to non-priority. The linear regression model revealed trend changes after the intervention, with both groups of municipalities showing a drop in the average monthly number of cases per 1,000 live births, with a reduction of -0·21 (CI 95% -0·33 to -0·09; p=0·0011) in priority municipalities and of -0·10 (CI 95% -0.19 to -0.02; p=0·0216) in non-priority municipalities.

Interpretation

The study using ITS provides important evidence on the direction, timing, and magnitude of the effects of interventions introduced as part of the SNP on congenital syphilis in Brazil. Our results suggest that the Syphilis No! Project influenced the trends of congenital syphilis in Brazil from 2018, with higher reductions achieved in the priority municipalities.

Funding

The research is funded by a grant to the Syphilis No! Project from Brazilian Ministry of Health (Project Number: 54/2017). The funders had no role in study design, analysis, decision to publish, or preparation of the manuscript.

Describing the burden of diphtheria in Canada from 2006 to 2017, using hospital administrative data and reportable disease data

Background

Canada has maintained a low incidence of toxigenic diphtheria since the 1990s, supported by continued commitment to publicly funded vaccination programs.

Objective

To determine whether hospitalization data, complemented with notifiable disease data, can describe the toxigenic respiratory and cutaneous diphtheria burden in Canada, and to assess if Canada is meeting its diphtheria vaccine-preventable disease-reduction target of zero annual cases of locally transmitted respiratory diphtheria.

Methods

Diphtheria-related hospital discharge data from 2006 to 2017 were extracted from the Discharge Abstract Database (DAD), and diphtheria case counts for the same period were retrieved from the Canadian Notifiable Disease Surveillance System (CNDSS), for descriptive analyses. As data from the province of Québec are not included in the DAD, CNDSS cases from Québec were excluded.

Results

A total of 233 diphtheria-related hospitalizations were recorded in the DAD. Of these, diphtheria was the most responsible diagnosis in 23. Half the patients were male (52%), and 57% were 60 years and older. Central region (Ontario) accounted for the most discharge records (61%), followed by Prairie region (Alberta, Manitoba and Saskatchewan; 23%). Cutaneous diphtheria accounted for 43% of records, and respiratory diphtheria accounted for 3%, with the remainder being other diphtheria complications or site unspecified. Two records with diphtheria as the most responsible diagnosis resulted in inpatient deaths. Eighteen cases of diphtheria were reported through CNDSS. Cases occurred in all age groups, with the largest proportions among those aged 20 to 59 years (39%) and those aged 19 years and younger (33%). Cases were only reported in the Prairie (89%) and West Coast (British Columbia; 11%) regions.

Conclusion

Hospital administrative data are consistent with the low incidence of diphtheria reported in CNDSS, and a low burden of respiratory diphtheria in Canada. Although Canada appears to be on track to meet its disease-reduction target, information on endemic transmission is not available.

Over 100 Years of Rift Valley Fever: A Patchwork of Data on Pathogen Spread and Spillover

During the past 100 years, Rift Valley fever virus (RVFV), a mosquito-borne virus, has caused potentially lethal disease in livestock, and has been associated with significant economic losses and trade bans. Spillover to humans occurs and can be fatal. Here, we combined data on RVF disease in humans (22 countries) and animals (37 countries) from 1931 to 2020 with seroprevalence studies from 1950 to 2020 (n = 228) from publicly available databases and publications to draw a more complete picture of the past and current RVFV epidemiology. RVFV has spread from its original locus in Kenya throughout Africa and into the Arabian Peninsula. Throughout the study period seroprevalence increased in both humans and animals, suggesting potentially increased RVFV exposure. In 24 countries, animals or humans tested positive for RVFV antibodies even though outbreaks had never been reported there, suggesting RVFV transmission may well go unnoticed. Among ruminants, sheep were the most likely to be exposed during RVF outbreaks, but not during periods of cryptic spread. We discuss critical data gaps and highlight the need for detailed study descriptions, and long-term studies using a one health approach to further convert the patchwork of data to the tale of RFV epidemiology.

Notifiable diseases interoperable framework toward improving Iran public health surveillance system: Lessons learned from COVID-19 pandemic

BACKGROUND

Direct transmission of notifiable disease information in a real-time and reliable way to public health decision-makers is imperative for early identification of epidemiological trends as well as proper response to potential pandemic like ongoing coronavirus disease 2019 crisis. Thus, this research aimed to develop of semantic-sharing and collaborative-modeling to meet the information exchange requirements of Iran's notifiable diseases surveillance system.

MATERIALS AND METHODS

First, the Iran's Notifiable diseases Minimum Data Set (INMDS) was determined according to a literature review coupled with agreements of experts. Then the INMDS was mapped to international terminologies and classification systems, and the Health Level seven-Clinical Document Architecture (HL7-CDA) standard was leveraged to define the exchangeable and machine-readable data formats.

RESULTS

A core dataset consisting of 15 classes and 96 data fields was defined. Data elements and response values were mapped to Systematized Nomenclature of Medicine-Clinical Terms (SNOMED-CT) reference terminology. Then HL7-CDA standard for interoperable data exchange were defined.

CONCLUSION

The notifiable disease surveillance requires an integrative participation of multidisciplinary team. In this field, data interoperability is more essential due to the heterogeneous nature of health information systems. Developing of INMDS based on HL7-CDA along with SNOMED-CT codes offers an inclusive and interoperable dataset that can help make notifiable diseases data more comparable and reportable across studies and organizations. The proposed data model will be further modifications in the future according probable changes in Iran's notifiable diseases list.

The improving state of Q fever surveillance. A review of Queensland notifications, 2003-2017

Q fever is a notifiable zoonotic disease in Australia, caused by infection with Coxiella burnetii. This study has reviewed 2,838 Q fever notifications reported in Queensland between 2003 and 2017 presenting descriptive analyses, with counts, rates, and proportions. For this study period, Queensland accounted for 43% of the Australian national Q fever notifications. Enhanced surveillance follow-up of Q fever cases through Queensland Public Health Units was implemented in 2012, which improved the data collected for occupational risk exposures and animal contacts. For 2013-2017, forty-nine percent (377/774) of cases with an identifiable occupational group would be considered high risk for Q fever. The most common identifiable occupational group was agricultural/farming (31%). For the same period, at-risk environmental exposures were identified in 82% (961/1,170) of notifications; at-risk animal-related exposures were identified in 52% (612/1,170) of notifications; abattoir exposure was identified in 7% of notifications. This study has shown that the improved follow-up of Q fever cases since 2012 has been effective in the identification of possible exposure pathways for Q fever transmission. This improved surveillance has highlighted the need for further education and heightened awareness of Q fever risk for all people living in Queensland, not just those in previously-considered high risk occupations.

Challenges in Infection Epidemiology: On the Underreporting of Norovirus Gastroenteritis Cases in Germany

It is commonly accepted that the number of officially reported incidences of norovirus (NoV) according to the German Protection against Infection Act (Infektionsschutzgesetz) does not reflect the ‘true’ incidence of NoV in Germany. This study aims to reveal the reasons for the underreporting of NoV cases by comparing secondary data. Methods: NoV incidence (cases per 100,000 reference persons) in the age group 18–65 was derived from register data of four different sources in the German public health system (2011–2015): Statutory health insurance in the federal state of Lower Saxony (AOK; in- and outpatient cases), the Research Institute of Ambulatory Health Care in Germany (ZI; outpatient cases), the German Federal Statistical Office (inpatient cases; DESTATIS), and the Robert Koch Institute (RKI SurvStat; health reporting data). Results: the incidence derived from the AOK in Lower Saxony varied between 49 and 66 NoV cases per 100,000 persons and was thus lower than at the federal level. Incidences of all inpatient and outpatient data were lower than the incidence according to the RKI in the last 2–3 years of the observation period. Conclusions: the disagreement between NoV incidences calculated from secondary inpatient and outpatient data and the respective numbers published by the RKI can be regarded as an indication that not all NoV cases were reported to public health authorities. This might be due to missed cases during the notification procedure or misclassification of gastroenteritis cases by general practitioners. Considering the limitations associated with analyzing secondary data, the appropriateness of these assumptions should be verified in future studies.

Threat to the French Swine Industry of African Swine Fever: Surveillance, Spread, and Control Perspectives

African swine fever (ASF) has one of the highest case-fatality rates among pig diseases. Europe was considered ASF-free for about two decades until 2007, when the virus was introduced into Georgia. Since then, it has been identified throughout Eastern Europe, and reached Belgium in late 2018, increasing the risk of ASF being introduced into neighboring countries-namely Germany, Luxembourg, the Netherlands, and France. French authorities have therefore reinforced surveillance measures to improve the probability of detecting ASF rapidly if it emerges in France. Predictive modeling may help to anticipate the extent of virus spread and evaluate the efficiency of these surveillance measures. A previously published and well-documented model that simulates ASF virus spread was therefore tailored to realistically represent the French situation in terms of the geographic distribution of swine production sites and the commercial trade between them on the one hand, and the implementation of surveillance protocols on the other. The outcomes confirmed the moderate spread of ASF through the swine trade network, a situation that had been previously highlighted for the case of Denmark. However, the diversity of the French pig production landscape has revealed a huge potential for the geographic dispersal of the virus, especially should the index case occur in a low-density area, with a median source-to-case distance reaching 300 km. Free-range herds, which are more likely to have interactions with wild boars, were also identified as potential entrance gate for the virus. Transmissions from conventional herds were quasi-exclusively due to swine movement on the commercial network, representing 99% of transmission events. In contrast, 81% of transmission events occurred in the neighborhood of the index herd when the virus was introduced in free-range herds. The current surveillance measures were found relatively efficient for detecting the virus in large herds, leading to detection rates of 94%. However, infections on smaller production sites-which often have free-range herds-were more difficult to detect and would require screening protocols specifically targeting these smaller herds.

Surveillance of Human Rabies by National Authorities--A Global Survey

Effective prevention of deaths due to human rabies is currently hampered by a lack of understanding of the scale of the problem, and the distribution of both animal and human cases across countries, regions and continents. Unfortunately, despite the severity of the disease, accurate data on which to assess these questions and to prioritize and direct public health interventions are not available for many parts of the world. This survey sought to understand the current global situation regarding the surveillance of human rabies. Data were collected from 91 countries across all continents and all categories of human rabies risk, generating the most complete and representative global data set currently available. Respondents were asked key questions about whether human rabies was a notifiable disease, how the surveillance system for human rabies operated and whether the respondent considered that the surveillance system was working effectively. Across the 91 countries from which data were collated, human rabies was a notifiable disease in all but eight. Despite international guidance, surveillance systems were very varied. Even where rabies is a notifiable disease, many countries had surveillance system judged to be ineffective, almost all of these being high and moderate rabies risk countries in Africa and Asia. Overall, 41% of the population covered by this survey (around 2.5 billion people) live in countries where there is no or ineffective rabies surveillance. The lack of robust surveillance is hindering rabies control efforts. However, whilst worldwide rabies surveillance would be improved if rabies were notifiable in all countries, many other challenges to the implementation of effective global human rabies surveillance systems remain.

Understanding the effect of miliary tuberculosis through the experience of one young person

In the UK, tuberculosis (TB) is on the increase. Miliary TB affects the lungs and can leave lasting damage, and affect a person's quality of life adversely. Healthcare professionals need to co-ordinate services efficiently, to ensure a smooth transition from hospital to home, and ensure there is appropriate support in the community for as long as necessary. In this article, a boy describes his journey through the illness: the associated bewilderment, deterioration, pain, fear and isolation; the emergencies; the prolonged but effective treatment; the care he received; and the support of his family. On discharge, he was still breathless and found it difficult to adapt to home life but, with thorough planning of his support with healthcare professionals, parents and relevant agencies, he was able to get back to school and continue his education.

Surveillance of fish diseases in the Nordic countries

Due to the increasing importance of disease problems in the fish farming industry and the impact disease may have on both feral and farmed fish in the Nordic countries, monitoring and surveillance on diseases have for many years been considered to be of socioeconomic importance. All the Nordic countries have a national legislation as basis for their surveillance and disease control in aquatic animals and regulations listing notifiable diseases of concern to the countries. The list of diseases vary between the countries. In addition, Denmark, Finland and Sweden are ruled by Directive 91/67/EEC as regards placing on the market of aquaculture animals and products. The surveillance for viral diseases in all the Nordic countries has mainly been based on the testing procedures given in the EU Commission Decision 96/240/EC.