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Background
For almost two decades, chlamydia and gonorrhoea diagnosis rates in remote Indigenous communities have been up to 30 times higher than for non-Indigenous Australians. The high levels of population movement known to occur between remote communities may contribute to these high rates.
Methods
We developed an individual-based computer simu...
Citations
... Recent modelling work suggests that high population C mobility likely contributes to high levels of STI prevalence among remote indigenous communities in Australia. 54 ...
Identifying groups most at risk of sexually transmissible infections (STIs) is important for prioritising screening, targeting prevention strategies and alleviating the burden of STIs. However, identifying those at risk of STIs is complicated by stigma associated with STIs, undisclosed risk behaviour, and the fact that STI epidemics are diversifying beyond traditional risk groups typically characterised by demographics and sexual behaviours alone. In this review, we describe the epidemiology of STIs among traditional and emerging risk groups, particularly in the context of uptake of HIV pre-exposure prophylaxis (PrEP), increasing STI transmission among heterosexual people, and the concentration of STI burden among specific subgroups not readily identifiable by health services. Risk diversification poses significant challenges, not only for risk-based testing, but also for the costs and resources required to reach a broader range of constituents with preventive and health promotion interventions. As drivers of STI risk are not purely behavioural, but relate to relative STI prevalence within sexual networks and access to sexual health care and testing, localised surveillance and research is important in ensuring risk is appropriately understood and addressed within local contexts. Here, we review the evidence on the benefits and harms of risk-guided versus population-based screening for STIs among key populations, discuss the importance of risk-guided interventions in the control of STIs, and explore contemporary approaches to risk determination.
... We extended a previously published individual-based simulation model of sexually transmitted infections (STIs) in heterosexual Aboriginal people to capture the syphilis outbreak across the affected regions [10]. A summary of the model's characteristics and our modeling methodology follows, with the Supplementary Material providing further details. ...
Background:
A syphilis outbreak among Australian Aboriginal and Torres Strait Islander people (respectfully referred to as Aboriginal) has resulted in almost 4000 notifications by 2020, with several congenital syphilis cases and infant deaths. Outbreak control efforts became coordinated under a National enhanced test and treat response in 2017. We evaluated the impact of these efforts and of expansion of testing interventions on syphilis prevalence.
Methods:
We developed an individual-based mathematical model of infectious syphilis transmission among young heterosexual Aboriginal people aged 15-34 years living in and moving between regional and remote areas, and we assessed the impact of existing and hypothetical outbreak control responses on syphilis prevalence.
Results:
The increased testing coverage achieved through the response (from 18% to 39% over 2011-2020) could stabilize the epidemic from 2021. To return to pre-outbreak prevalence (<0.24%) by 2025, testing coverage must reach 60%. The addition of annual community-wide screening, where 30% of youth in communities are tested over 6 weeks, would reduce prevalence to the pre-outbreak level within 4 years. If testing coverage had been scaled-up to 60% at the start of outbreak in mid-2011, the outbreak would have been mitigated.
Conclusions:
Our results suggest that to control the syphilis outbreak, the response needs to be delivered to enable the maximum coverage of testing to be reached in the shortest time to reduce the prevalence to pre-outbreak levels. Reduction could be hastened with community-wide screening at similar time periods across all communities together with increases in annual testing coverage.
... The huge influx of internal migrants into urban areas has greatly increased the density of China's urban population and exacerbated the proliferation of infectious diseases such as AIDS and STDs (Hui et al., 2013). Our findings suggest that internal migration in China is an important predictor of the liberalization of sexual attitudes and that Internet usage will accentuate this effect. ...
Using nationally representative data from China, this paper investigated the impact of internal migration on sexual attitudes and whether this relationship is moderated by Internet use. We provided evidence that internal migration had a significantly positive impact on attitudes toward the acceptance of premarital sex, extramarital sex , and homosexuality. We also found that the positive nexus between internal migration and
sexual attitudes was moderated by Internet use. The results further indicated that internal migration influenced sexual attitudes through extrication from traditional gender role values, the deterioration of subjective well-being , and the improvement of economic status.
... An individual-based model, repurposed from a framework developed to examine dynamics of sexually transmitted infections in remote Australia, is used to explicitly represent each community member [12]. Community sizes comprising 100, 500, 1000 or 3500 people are modelled, with results presented here focusing on communities of 1000 people but noting key differences. ...
Background
Remote Australian Aboriginal and Torres Strait Islander communities have potential to be severely impacted by COVID-19, with multiple factors predisposing to increased transmission and disease severity. Our modelling aims to inform optimal public health responses.
Methods
An individual-based simulation model represented SARS-CoV2 transmission in communities ranging from 100 to 3500 people, comprised of large, interconnected households. A range of strategies for case finding, quarantining of contacts, testing, and lockdown were examined, following the silent introduction of a case.
Results
Multiple secondary infections are likely present by the time the first case is identified. Quarantine of close contacts, defined by extended household membership, can reduce peak infection prevalence from 60 to 70% to around 10%, but subsequent waves may occur when community mixing resumes. Exit testing significantly reduces ongoing transmission. Concurrent lockdown of non-quarantined households for 14 days is highly effective for epidemic control and reduces overall testing requirements; peak prevalence of the initial outbreak can be constrained to less than 5%, and the final community attack rate to less than 10% in modelled scenarios. Lockdown also mitigates the effect of a delay in the initial response. Compliance with lockdown must be at least 80–90%, however, or epidemic control will be lost.
Conclusions
A SARS-CoV-2 outbreak will spread rapidly in remote communities. Prompt case detection with quarantining of extended-household contacts and a 14 day lockdown for all other residents, combined with exit testing for all, is the most effective strategy for rapid containment. Compliance is crucial, underscoring the need for community supported, culturally sensitive responses.
... The collection of clinical dental examination data relies on the participant having the wherewithal to locate and travel to a local dental public health clinic; but no assistance with transportation is provided. Follow-up questionnaires require a postal address, but many Indigenous Australians change their residential addresses frequently in a given year [34]. The questions/instruments/scales used in surveys are typically based on Western values and constructs, with minimal attempts to test the validity in an indigenous context. ...
There are currently 370 million persons identifying as indigenous across 90 countries globally. Indigenous peoples generally face substantial exclusion/marginalization and poorer health status compared with non-indigenous majority populations; this includes poorer oral health status and reduced access to dental services. Population-level oral health surveys provide data to set priorities, inform policies, and monitor progress in dental disease experience/dental service utilisation over time. Rigorously and comprehensively measuring the oral health burden of indigenous populations is an ethical issue, though, given that survey instruments and sampling procedures are usually not sufficiently inclusive. This results in substantial underestimation or even biased estimation of dental disease rates and severity among indigenous peoples, making it difficult for policy makers to prioritise resources in this area. The methodological challenges identified include: (1) suboptimal identification of indigenous populations; (2) numerator-denominator bias and; (3) statistical analytic considerations. We suggest solutions that can be implemented to strengthen the visibility of indigenous peoples around the world in an oral health context. These include acknowledgment of the need to engage indigenous peoples with all data-related processes, encouraging the use of indigenous identifiers in national and regional data sets, and mitigating and/or carefully assessing biases inherent in population oral health methodologies for indigenous peoples.
... An individual-based model, repurposed from a framework developed to examine dynamics of sexually transmitted infections in remote Australia, is used to explicitly represent each community member [10]. ...
Background
Remote Australian Aboriginal and Torres Strait Islander communities have potential to be severely impacted by COVID-19, with multiple factors predisposing to increased transmission and disease severity. Our modelling aims to inform optimal public health responses. Methods
An individual-based simulation model represented communities ranging from 100 to 3,500 people, comprised of large interconnected households. A range of strategies for case finding, quarantining of contacts, testing, and lockdown were examined, following the silent introduction of a case.ResultsMultiple secondary infections are likely present by the time the first case is identified. Quarantine of close contacts, defined by extended household membership, can reduce peak infection prevalence from 60-70% to around 10%, but subsequent waves may occur when community mixing resumes. Exit testing significantly reduces ongoing transmission. Concurrent lockdown of non-quarantined households for 14 days is highly effective for epidemic control and reduces overall testing requirements; peak prevalence of the initial outbreak can be constrained to less than 5%, and the final community attack rate to less than 10% in modelled scenarios. Lockdown also mitigates the effect of a delay in the initial response. Compliance with lockdown must be at least 80-90%, however, or epidemic control will be lost.ConclusionsA SARS-CoV-2 outbreak will spread rapidly in remote communities. Prompt case detection with quarantining of extended-household contacts and a 14-day lockdown for all other residents, combined with exit testing for all, is the most effective strategy for rapid containment. Compliance is crucial, underscoring the need for community supported, culturally sensitive responses.
... Although mathematical models have been developed to describe transmission of NG infection at a population level (for example Chan, McCabe and Fisman 2012;Hui et al. 2013;Hui et al. 2015;Fingerhuth et al. 2016), there has been very little focus on developing models capturing the course of NG infection at a within-host level. Such within-host models have been developed for other pathogens, describing the interaction between pathogen, host cells and host immune response (for example Nowak and Bangham 1996;Wilson, Timms and McElwain 2003;Smith, McCullers and Adler 2011;Colijn and Cohen 2015). ...
The bacterial species Neisseria gonorrhoeae (NG) has evolved to replicate effectively and exclusively in human epithelia, with its survival dependent on complex interactions between bacteria, host cells and antimicrobial agents. A better understanding of these interactions is needed to inform development of new approaches to gonorrhoea treatment and prevention but empirical studies have proven difficult, suggesting a role for mathematical modelling. Here we describe an in-host model of progression of untreated male symptomatic urethral infection, including NG growth and interactions with epithelial cells and neutrophils, informed by in vivo and in vitro studies. The model reproduces key observations on bacterial load and clearance and we use multivariate sensitivity analysis to refine plausible ranges for model parameters. Model variants are also shown to describe mouse infection dynamics with altered parameter ranges that correspond to observed differences between human and mouse infection. Our results highlight the importance of NG internalisation, particularly within neutrophils, in sustaining infection in the human model, with ∼80% of the total NG population internalised from day 25 on. This new mechanistic model of in-host NG infection dynamics should also provide a platform for future studies relating to antimicrobial treatment and resistance and infection at other anatomical sites.
... Overall, health service access forms an on-going issue for Aboriginal populations [245,246]. Barriers to prevention include transience and mobility patterns which increase difficulty of service access, testing, and likelihood of higher numbers of sexual partners [90,[247][248][249][250][251][252][253]. English as a non-primary language, as well as marked differences in lingual description and understanding of body parts, forms a significant barrier [237,239]. ...
This review was commissioned by the Department of Health WA as part of the development process for the fourth WA Aboriginal sexual health and blood-borne virus (SHBBV) strategy
(2019–2023). This strategy aims to prevent and reduce rates of infection in Australian communities.This review has followed the structure of the third strategy, analysing the data through each domain: prevention and education; testing and diagnosis; disease management and clinical care; workforce development; enabling environments, and; research, evaluation, and surveillance. The review aims to provide a broad overview of evidence on the way SHBBV health promotion, care, and research are negotiated with Aboriginal populations across three countries: Aotearoa/ New Zealand, Australia, and Canada. The data were collected through a scoping review of academic and grey literature (2005-2018), and further developed with the guidance of an advisory group. Culturally appropriate reviews can provide inroads to more constructive policy-making and research practices in health [45, 46]. Reviews can help to address the gaps in inclusive practice guidelines that are evident in current Australian Aboriginal health strategies, in part due to significant knowledge gaps [47]. In particular, reviews which utilise ‘decolonising methodologies’ (such as stakeholder consultation and the expansion of what can be considered ‘valid’ knowledge) can include research that is informed by the needs of communities, as well as the data collected through standard literature searches [48]. Decolonisation, the positioning of Aboriginal-led frameworks at the fore of service delivery, is a crucial aspect of positive and constructive health care, promotion, and research for Aboriginal people [49-51]. It involves directly engaging affected communities, keeping Aboriginal voices amplified and considered throughout institutional processes, practicing reflexivity and immersion, and ensuring that any research or health care/promotion outcomes are addressed with an Aboriginal lens in mind [51-53].
... 30 The analysis showed that overall~42% of individuals who tested positive for CT or NG at remote primary health centres were re-tested at 2-12 months, with only 15% re-tested in the guideline-recommended period of 2-4 months and the remainder at 5-12 months. Although re-testing at 5-12 months is still a good public health outcome, 35 re-testing at 3 months is preferred to reduce the risk of PID and onward transmission. Re-testing at 5-12 months was higher in 25-29 year old females compared with females in other age groups, which may be due to more opportunities for testing, as this age group is more likely to attend health services. ...
Background Extremely high rates of diagnosis of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) have been recorded in remote communities across northern and central Australia. Re-testing at 3 months, after treatment administered, of CT or NG is recommended to detect repeat infections and prevent morbidity and ongoing transmission.
Methods:
Baseline CT and NG laboratory data (2009-2010) from 65 remote health services participating in a cluster randomised trial was used to calculate the proportion of individuals re-tested after an initial CT or NG diagnosis at <2 months (not recommended), 2-4 months (recommended) and 5-12 months and the proportion with repeat positivity on re-test. To assess if there were difference in re-testing and repeat positivity by age group and sex, t-tests were used.
Results:
There was a total of 2054 people diagnosed with CT and/or NG in the study period; 14.9% were re-tested at 2-4 months, 26.9% at 5-12 months, a total of 41.8% overall. Re-testing was higher in females than in males in both the 2-4-month (16.9% v. 11.5%, P<0.01) and 5-12-month (28.9% v. 23.5%, P=0.01) periods. Women aged 25-29 years had a significantly higher level of re-testing 5-12 months post-diagnosis than females aged 16-19 years (39.8% v. 25.4%, P<0.01). There was a total of 858 people re-tested at 2-12 months and repeat positivity was 26.7%. There was higher repeat NG positivity than repeat CT positivity (28.8% v. 18.1%, P<0.01).
Conclusions:
Just under half the individuals diagnosed with CT or NG were re-tested at 2-12 months post-diagnosis; however, only 15% were re-tested in the recommended time period of 2-4 months. The higher NG repeat positivity compared with CT is important, as repeat NG infections have been associated with higher risk of pelvic inflammatory disease-related hospitalisation. Findings have implications for clinical practice in remote community settings and will inform ongoing sexual health quality improvement programs in remote community clinics.
... High rates of casual sexthough with no higher numbers of partners than the general populationmay put Aboriginal people at higher risk (Bryant et al., 2011). High mobility may also play a part in the epidemiology of STIs in Aboriginal communities (Hui et al., 2013). Consistent condom use in casual sex is low, but no lower than in the general population (Bryant et al., 2011). ...
Australia is largely secular, with about 50% reporting a religion in surveys. Attitudes are tolerant, with a majority regarding homosexual acts and abortion as acceptable, and few disapproving of premarital sex. However, sex outside a committed relationship is widely disapproved of. Use of contraception is high. States differ in legislation and policing of the sex industry. Just over half of adolescents have sexual intercourse before they leave high school. Condom use at first intercourse is high, but many adults do not use condoms even with casual partners. Sex education is very patchy. HIV has remained largely concentrated among homosexually active men.
