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"El-Hayek, Carol"
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Eliminating hepatitis C virus as a public health threat among HIV‐positive men who have sex with men: a multi‐modelling approach to understand differences in sexual risk behaviour
by
Keiser, Olivia
,
El‐Hayek, Carol
,
Hellard, Margaret
in
Acquired immune deficiency syndrome
,
agent‐based model
,
AIDS
2018
Introduction Outbreaks of hepatitis C virus (HCV) infections among HIV‐positive men who have sex with men (MSM) have been observed globally. Using a multi‐modelling approach we estimate the time and number of direct‐acting antiviral treatment courses required to achieve an 80% reduction in HCV prevalence among HIV‐positive MSM in the state of Victoria, Australia. Methods Three models of HCV transmission, testing and treatment among MSM were compared: a dynamic compartmental model; an agent‐based model (ABM) parametrized to local surveillance and behavioural data (“ABM1”); and an ABM with a more heterogeneous population (“ABM2”) to determine the influence of extreme variations in sexual risk behaviour. Results Among approximately 5000 diagnosed HIV‐positive MSM in Victoria, 10% are co‐infected with HCV. ABM1 estimated that an 80% reduction in HCV prevalence could be achieved in 122 (inter‐quartile range (IQR) 112 to 133) weeks with 523 (IQR 479 to 553) treatments if the average time from HCV diagnosis to treatment was six months. This was reduced to 77 (IQR 69 to 81) weeks if the average time between HCV diagnosis and treatment commencement was decreased to 16 weeks. Estimates were consistent across modelling approaches; however ABM2 produced fewer incident HCV cases, suggesting that treatment‐as‐prevention may be more effective in behaviourally heterogeneous populations. Conclusions Major reductions in HCV prevalence can be achieved among HIV‐positive MSM within two years through routine HCV monitoring and prompt treatment as a part of HIV care. Compartmental models constructed with limited behavioural data are likely to produce conservative estimates compared to models of the same setting with more complex parametrizations.
Journal Article
Phylogenetic clustering networks among heterosexual migrants with new HIV diagnoses post-migration in Australia
by
Marukutira, Tafireyi
,
Hellard, Margaret
,
El Hayek, Carol
in
Biology and Life Sciences
,
Birth
,
Bisexual
2020
It is estimated that approximately half of new HIV diagnoses among heterosexual migrants in Victoria, Australia, were acquired post-migration. We investigated the characteristics of phylogenetic clusters in notified cases of HIV among heterosexual migrants. Partial HIV pol sequences obtained from routine clinical genotype tests were linked to Victorian HIV notifications with the following exposures listed on the notification form: heterosexual sexual contact, injecting drug use, bisexual sexual contact, male-to male sexual contact or heterosexual sexual contact in combination with injecting drug use, unknown exposure. Those with heterosexual sexual contact as the only exposure were the focus of this study, with the other exposures included to better understand transmission networks. Additional reference sequences were extracted from the Los Alamos database. Maximum likelihood methods were used to infer the phylogeny and the robustness of the resulting tree was assessed using bootstrap analysis. Phylogenetic clusters were defined on the basis of bootstrap and genetic distance. HIV pol sequences were available for 332 of 445 HIV notifications attributed to only heterosexual sexual contact in Victoria from 2005-2014. Forty-three phylogenetic clusters containing at least one heterosexual migrant were detected, 30 (70%) of which were pairs. The characteristics of these phylogenetic clusters varied considerably by cluster size. Pairs were more likely to be composed of people living with HIV from a single country of birth (p = 0.032). Larger clusters (n[greater than or equal to]3) were more likely to contain people born in Australian/New Zealand (p = 0.002), migrants from more than one country of birth (p = 0.013) and viral subtype-B, the most common subtype in Australia (p = 0.006). Pairs were significantly more likely to contain females (p = 0.037) and less likely to include HIV diagnoses with male-to-male sexual contact reported as a possible exposure (p<0.001) compared to larger clusters (n[greater than or equal to]3). Migrants appear to be at elevated risk of HIV acquisition, in part due to intimate relationships between migrants from the same country of origin, and in part due to risks associated with the broader Australian HIV epidemic. However, there was no evidence of large transmission clusters driven by heterosexual transmission between migrants. A multipronged approach to prevention of HIV among migrants is warranted.
Journal Article
Two decades of surveillance data show late presentation among a diverse group of women diagnosed with HIV in Victoria, Australia
by
Moreira, Clarissa
,
Hellard, Margaret
,
El‐Hayek, Carol
in
Acquired immune deficiency syndrome
,
Adolescent
,
Adult
2019
To develop an HIV response suited to women and to inform appropriate services, we describe the characteristics of women diagnosed and living with HIV using 22 years of high‐quality surveillance data.
Data on women newly diagnosed with HIV between 1994 and 2016 and women living with diagnosed HIV in Victoria at 31 December 2016 were extracted from the Victorian Public Health Surveillance System. Descriptive analysis by place of birth was performed and Poisson regression used to assess trends over time.
There were 465 new diagnoses among women in Victoria between 1994 and 2016 and 613 women living with HIV in 2016. Women were diagnosed late, and frequently reported no HIV testing history, AIDS‐defining illness or other symptoms of HIV at diagnosis. These indicators of delayed diagnosis were even greater for non‐Australian‐born women.
For Victoria to reach the ambitious targets for diagnosis, treatment and viral suppression in 95% of people living with HIV, prevention programs and efforts to increase early diagnosis as well as support services must consider the epidemiology and diversity of women.
Journal Article
Routine feedback of test results to participants in clinic- and survey-based surveillance of HIV
by
Baggaley, Rachel
,
Obermeyer, Carla
,
El-Hayek, Carol
in
Acceptability
,
Acquired immune deficiency syndrome
,
AIDS
2015
Surveillance for human immunodeficiency virus (HIV) in low- and middle-income countries started in the 1980s. However, the questions of whether the results of HIV tests should be given to participants, and if so how, has still not been resolved. In the absence of effective treatment, it was considered acceptable to withhold results from HIV-positive participants. However, when antiretroviral treatment is available, some argue for beneficence - that it is the researcher's duty to return the test results to all those who provide samples for surveillance. The corollary is that only participants who wish to receive their test results would be eligible to participate in surveys. Others argue for autonomy - that to obtain a more representative result for the general population, surveys should not exclude participants who do not wish to receive their test results. This round table discussion takes a closer look at those two arguments. We believe that the global community should work towards routine feedback of HIV surveillance while ensuring that participants receive and understand their test results.
Journal Article
Gaps in the HIV diagnosis and care cascade for migrants in Australia, 2013–2017: A cross-sectional study
by
Marukutira, Tafireyi
,
Moreira, Clarissa
,
Douglass, Caitlin
in
Acquired immune deficiency syndrome
,
AIDS
,
Antiretroviral drugs
2020
Globally, few studies compare progress toward the Joint United Nations Program on HIV/AIDS (UNAIDS) Fast-Track targets among migrant populations. Fast-Track targets are aligned to the HIV diagnosis and care cascade and entail achieving 90-90-90 (90% of people living with HIV [PLHIV] diagnosed, 90% of those diagnosed on treatment, and 90% of those on treatment with viral suppression [VS]) by 2020 and 95-95-95 by 2030. We compared cascades between migrant and nonmigrant populations in Australia.
We conducted a serial cross-sectional survey for HIV diagnosis and care cascades using modelling estimates for proportions diagnosed combined with a clinical database for proportions on treatment and VS between 2013-2017. We estimated the number of PLHIV and number diagnosed using New South Wales (NSW) and Victorian (VIC) data from the Australian National HIV Registry. Cascades were stratified by migration status, sex, HIV exposure, and eligibility for subsidised healthcare in Australia (reciprocal healthcare agreement [RHCA]). We found that in 2017, 17,760 PLHIV were estimated in NSW and VIC, and 90% of them were males. In total, 90% of estimated PLHIV were diagnosed. Of the 9,391 who were diagnosed and retained in care, most (85%; n = 8,015) were males. We excluded 38% of PLHIV with missing data for country of birth, and 41% (n = 2,408) of eligible retained PLHIV were migrants. Most migrants were from Southeast Asia (SEA; 28%), northern Europe (12%), and eastern Asia (11%). Most of the migrants and nonmigrants were males (72% and 83%, respectively). We found that among those retained in care, 90% were on antiretroviral therapy (ART), and 95% of those on ART had VS (i.e., 90-90-95). Migrants had larger gaps in their HIV diagnosis and care cascade (85-85-93) compared with nonmigrants (94-90-96). Similarly, there were larger gaps among migrants reporting male-to-male HIV exposure (84-83-93) compared with nonmigrants reporting male-to-male HIV exposure (96-92-96). Large gaps were also found among migrants from SEA (72-87-93) and sub-Saharan Africa (SSA; 89-93-91). Migrants from countries ineligible for RHCA had lower cascade estimates (83-85-92) than RHCA-eligible migrants (96-86-95). Trends in the HIV diagnosis and care cascades improved over time (2013 and 2017). However, there was no significant increase in ART coverage among migrant females (incidence rate ratio [IRR]: 1.03; 95% CI 0.99-1.08; p = 0.154), nonmigrant females (IRR: 1.01; 95% CI 0.95-1.07; p = 0.71), and migrants from SEA (IRR: 1.03; 95% CI 0.99-1.07; p = 0.06) and SSA (IRR: 1.03; 95% CI 0.99-1.08; p = 0.11). Additionally, there was no significant increase in VS among migrants reporting male-to-male HIV exposure (IRR: 1.02; 95% CI 0.99-1.04; p = 0.08). The major limitation of our study was a high proportion of individuals missing data for country of birth, thereby limiting migrant status categorisation. Additionally, we used a cross-sectional instead of a longitudinal study design to develop the cascades and used the number retained as opposed to using all individuals diagnosed to calculate the proportions on ART.
HIV diagnosis and care cascades improved overall between 2013 and 2017 in NSW and VIC. Cascades for migrants had larger gaps compared with nonmigrants, particularly among key migrant populations. Tracking subpopulation cascades enables gaps to be identified and addressed early to facilitate achievement of Fast-Track targets.
Journal Article
The impact of universal access to direct-acting antiviral therapy on the hepatitis C cascade of care among individuals attending primary and community health services
by
Carter, Allison
,
Traeger, Michael W.
,
Pedrana, Alisa E.
in
Antibodies
,
Antiviral agents
,
Antiviral drugs
2020
Hepatitis C elimination will require widespread access to treatment and responses at the health-service level to increase testing among populations at risk. We explored changes in hepatitis C testing and the cascade of care before and after the introduction of direct-acting antiviral treatments in Victoria, Australia. De-identified clinical data were retrospectively extracted from eighteen primary care clinics providing services targeted towards people who inject drugs. We explored hepatitis C testing within three-year periods immediately prior to (pre-DAA period) and following (post-DAA period) universal access to DAA treatments on 1.sup.st March 2016. Among ever RNA-positive individuals, we constructed two care cascades at the end of the pre-DAA and post-DAA periods. The number of individuals HCV-tested was 13,784 (12.2% of those with a consultation) in the pre-DAA period and 14,507 (10.4% of those with a consultation) in the post-DAA period. The pre-DAA care cascade included 2,515 RNA-positive individuals; 1,977 (78.6%) were HCV viral load/genotype tested; 19 (0.8%) were prescribed treatment; and 12 had evidence of cure (0.5% of those RNA-positive and 63.6% of those eligible for cure). The post-DAA care cascade included 3,713 RNA-positive individuals; 3,276 (88.2%) were HCV viral load/genotype tested; 1,674 (45.1%) were prescribed treatment; and 863 had evidence of cure (23.2% of those RNA-positive and 94.9% of those eligible for cure). Marked improvements in the cascade of hepatitis C care among patients attending primary care clinics were observed following the universal access of DAA treatments in Australia, although improvements in testing were less pronounced.
Journal Article
Aiming for 90–90–90 – the importance of understanding the risk factors for HIV exposure and advanced HIV infection in migrant populations and other groups who do not report male-to-male sex
by
Hellard, Margaret
,
El Hayek, Carol
,
Lemoh, Chris
in
Acquired immune deficiency syndrome
,
AIDS
,
Birth order
2018
Background In Australia, new HIV diagnoses increasingly occur among people who do not report male-to-male sex. Among migrants, it is not clear what proportion acquired infection before migration. Similarly, among Australian-born people, it is not clear what proportion acquired infection in-country. There is a need to better understand the epidemiology of HIV in people who do not report male-to-male sex.
Victorian public health surveillance data were used to classify migrants as having likely acquired HIV before or after arrival to Australia using a CD4 cell count decline method to estimate date of infection. Place of exposure for Australian-born people was estimated based on self-report. Factors associated with place of HIV acquisition, advanced infection and newly acquired infection were explored among migrants and among Australian-born people.
Between July 1996 and June 2014, there were 821 new non-MSM HIV diagnoses. Most (58%) were migrants, and of these, half (54%) were estimated to have acquired HIV before migration. Among Australian-born people, 27% reported exposure likely occurring abroad; the majority of these were men who reported exposure in South-East Asia. Advanced infection was common in migrants (45%) and Australian-born people (35%). Among migrants, birth in South-East Asia was associated with increased odds of advanced infection.
These results highlight the potential vulnerability of migrants after arrival in Australia, especially those from South-East Asia and Sub-Saharan Africa, and that of Australian-born men travelling to these regions. Public health practice must be strengthened to meet prevention needs of these populations in line with Australian policy.
Journal Article
Phenotyping people with a history of injecting drug use within electronic medical records using an interactive machine learning approach
by
Wilkinson, Anna
,
Curtis, Michael
,
Boyle, Douglas I. R.
in
692/308/174
,
692/499
,
692/700/478/174
2024
People with a history of injecting drug use are a priority for eliminating blood-borne viruses and sexually transmissible infections. Identifying them for disease surveillance in electronic medical records (EMRs) is challenged by sparsity of predictors. This study introduced a novel approach to phenotype people who have injected drugs using structured EMR data and interactive human-in-the-loop methods. We iteratively trained random forest classifiers removing important features and adding new positive labels each time. The initial model achieved 92.7% precision and 93.5% recall. Models maintained >90% precision and recall after nine iterations, revealing combinations of less obvious features influencing predictions. Applied to approximately 1.7 million patients, the final model identified 128,704 (7.7%) patients as potentially having injected drugs, beyond the 50,510 (2.9%) with known indicators of injecting drug use. This process produced explainable models that revealed otherwise hidden combinations of predictors, offering an adaptive approach to addressing the inherent challenge of inconsistently missing data in EMRs.
Journal Article
Clinic Network Collaboration and Patient Tracing to Maximize Retention in HIV Care
by
Eu, Beng
,
Chen, Marcus
,
Street, Alan
in
Acquired immune deficiency syndrome
,
AIDS
,
Antiretroviral agents
2015
Understanding retention and loss to follow up in HIV care, in particular the number of people with unknown outcomes, is critical to maximise the benefits of antiretroviral therapy. Individual-level data are not available for these outcomes in Australia, which has an HIV epidemic predominantly focused amongst men who have sex with men.
A network of the 6 main HIV clinical care sites was established in the state of Victoria, Australia. Individuals who had accessed care at these sites between February 2011 and June 2013 as assessed by HIV viral load testing but not accessed care between June 2013 and February 2014 were considered individuals with potentially unknown outcomes. For this group an intervention combining cross-referencing of clinical data between sites and phone tracing individuals with unknown outcomes was performed. 4966 people were in care in the network and before the intervention estimates of retention ranged from 85.9%-95.8% and the proportion with unknown outcomes ranged from 1.3-5.5%. After the intervention retention increased to 91.4-98.8% and unknown outcomes decreased to 0.1-2.4% (p<.01 for all sites for both outcomes). Most common reasons for disengagement from care were being too busy to attend or feeling well. For those with unknown outcomes prior to the intervention documented active psychiatric illness at last visit was associated with not re-entering care (p = 0.04).
The network demonstrated low numbers of people with unknown outcomes and high levels of retention in care. Increased levels of retention in care and reductions in unknown outcomes identified after the intervention largely reflected confirmation of clinic transfers while a smaller number were successfully re-engaged in care. Factors associated with disengagement from care were identified. Systems to monitor patient retention, care transfer and minimize disengagement will maximise individual and population-level outcomes for populations with HIV.
Journal Article
Opt-Out and Opt-In Testing Increases Syphilis Screening of HIV-Positive Men Who Have Sex with Men in Australia
by
Baker, David
,
Wand, Handan
,
McNulty, Anna
in
Adult
,
Ambulatory care facilities
,
Australia - epidemiology
2013
Since 2005, Australian clinicians were advised to undertake quarterly syphilis testing for all sexually active HIV-positive men who have sex with men (MSM). We describe differences in syphilis testing frequency among HIV-positive MSM by clinic testing policies since this recommendation.
Three general practices, two sexual health clinics and two hospital HIV outpatient clinics provided data on HIV viral load and syphilis testing from 2006-2010. Men having ≥1 viral load test per year were included; >95% were MSM. We used Chi-2 tests to assess changes in syphilis testing frequency over time, and differences by clinic testing policy (opt-out, opt-in and risk-based).
The proportion of men having HIV viral loads with same-day syphilis tests increased from 37% in 2006 to 63% in 2007 (p<0.01) and 68-69% thereafter. In 2010, same-day syphilis testing was highest in four clinics with opt-out strategies (87%, range:84-91%) compared with one clinic with opt-in (74%, p = 0.121) and two clinics with risk-based strategies (22%, range:20-24%, p<0.01). The proportion of men having ≥3 syphilis tests per year increased from 15% in 2006 to 36% in 2007 (p<0.01) and 36-38% thereafter. In 2010, the proportion of men having ≥3 syphilis tests in a year was highest in clinics with opt-out strategies (48%, range:35-59%), compared with opt-in (39%, p = 0.121) and risk-based strategies (8.4%, range:5.4-12%, p<0.01).
Over five years the proportion of HIV-positive men undergoing syphilis testing at recommended frequencies more than doubled, and was 5-6 times higher in clinics with opt-out and opt-in strategies compared with risk-based policies.
Journal Article