Good continuum of HIV care in Belgium despite weaknesses in retention and linkage to care among migrants

Profile of Persons Recently Infected with HIV-1 in Belgium: New Insights to Tailor Prevention Efforts

Despite wide availability of prevention and treatment services, including the ongoing roll-out of pre-exposure prophylaxis (PrEP), the HIV epidemic is not under control in Belgium. Hence, there is a recognized need to improve case finding and early diagnosis to curb the further spread of HIV more effectively. The objective of the present study was to improve insight into the profiles of persons recently infected with HIV-1 and on their prevention trajectory. Between May 2018 and December 2022, we selected persons diagnosed in Belgium within three months of the presumed infection date. We then analyzed information collected using a questionnaire covering topics on HIV testing, sexually transmitted infections (STIs), PrEP use, sexual behavior, partner notification and substance use. The data obtained were analyzed alongside information derived from phylogenetic cluster analysis of the viral source of infection. A total of 93 persons with a recent HIV-1 infection completed the questionnaire, the majority (74%) being MSM, 14% were heterosexual women and 12% were heterosexual men. Nearly one-third of participants engaged in sexual activity with an average of 2 to 5 casual partners around the presumed time of infection. A significant percentage reported frequent substance use during sexual activity (65%), being previously diagnosed with STI (65%) and using condoms infrequently (44%). 63% reported a testing frequency of at least one HIV test per year before being diagnosed and 46% notified their previous sex partner(s) after being diagnosed. Over 20% of respondents (including 11 MSM, 4 heterosexual men and 5 heterosexual women) reported exclusive sexual activity with their steady partner. Eight participants (9%, all MSM, 75% born outside of Belgium) reported PrEP use in the past. No significant differences in behavioral characteristics were found between persons who were part of a local transmission cluster (48%) and persons that were not part of a cluster (47%). The study results revealed that the majority of persons diagnosed early with HIV-1 infection in Belgium exhibited characteristics corresponding to a high-at-risk population and were aware of this risk, as evidenced by a high testing frequency. However, partner notification rates were low and use and awareness of PrEP limited. A notable group of persons not corresponding to the high-risk profiles was also identified. This information may help to expose missed opportunities for prevention and contribute to enhancing the implementation of future prevention measures.

Statistical methods applied for the assessment of the HIV cascade and continuum of care: a systematic scoping review

OBJECTIVES

This scoping review aims to identify and synthesise existing statistical methods used to assess the progress of HIV treatment programmes in terms of the HIV cascade and continuum of care among people living with HIV (PLHIV).

DESIGN

Systematic scoping review.

DATA SOURCES

Published articles were retrieved from PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL) Complete and Excerpta Medica dataBASE (EMBASE) databases between April and July 2022. We also strategically search using the Google Scholar search engine and reference lists of published articles.

ELIGIBILITY CRITERIA

This scoping review included original English articles that estimated and described the HIV cascade and continuum of care progress in PLHIV. The review considered quantitative articles that evaluated either HIV care cascade progress in terms of the Joint United Nations Programme on HIV and AIDS targets or the dynamics of engagement in HIV care.

DATA EXTRACTION AND SYNTHESIS

The first author and the librarian developed database search queries and screened the retrieved titles and abstracts. Two independent reviewers and the first author extracted data using a standardised data extraction tool. The data analysis was descriptive and the findings are presented in tables and visuals.

RESULTS

This review included 300 articles. Cross-sectional study design methods were the most commonly used to assess the HIV care cascade (n=279, 93%). In cross-sectional and longitudinal studies, the majority used proportions to describe individuals at each cascade stage (276/279 (99%) and 20/21 (95%), respectively). In longitudinal studies, the time spent in cascade stages, transition probabilities and cumulative incidence functions was estimated. The logistic regression model was common in both cross-sectional (101/279, 36%) and longitudinal studies (7/21, 33%). Of the 21 articles that used a longitudinal design, six articles used multistate models, which included non-parametric, parametric, continuous-time, time-homogeneous and discrete-time multistate Markov models.

CONCLUSIONS

Most literature on the HIV cascade and continuum of care arises from cross-sectional studies. The use of longitudinal study design methods in the HIV cascade is growing because such methods can provide additional information about transition dynamics along the cascade. Therefore, a methodological guide for applying different types of longitudinal design methods to the HIV continuum of care assessments is warranted.

HIV among migrants in precarious circumstances in the EU and European Economic Area

HIV epidemics in the EU and European Economic Area are increasingly diverse in transmission modes and groups affected. Substantial gaps in data exist on HIV burden and access to the HIV continuum of care among migrants living in this region, particularly individuals in precarious circumstances such as migrants with irregular status. Migrants have a higher HIV burden compared with the general population, and high rates of post-migration HIV acquisition. Migrants also face challenges in access to health and HIV services, with irregular migrants, foreign-born key populations such as men who have sex with men, sex workers, and people who inject drugs, and migrants from sub-Saharan Africa being most affected. Intersecting factors negatively affect their access to services along the full continuum of care, including prevention and psychosocial services. Ensuring equitable access to general health and HIV services, regardless of immigration status, and implementing interventions to reduce stigma and discrimination are crucial to ending AIDS by 2030.

Baseline and Process Factors of Anti-Retroviral Therapy That Predict Loss to Follow-up Among People Living with HIV/AIDS in China: A Retrospective Cohort Study

We explored the predictors and predictive models of loss to follow-up (LTFU) during the first year of anti-retroviral therapy (ART). LTFU was defined as the failure to visit the clinic for antiretroviral drugs for ≥ 90 days after the last missed scheduled visit. Based on the electronic medical records of 5953 patients who were HIV positive and began ART between 2016 and 2019 in China, the LTFU rate was 7.24 (95% confidence interval 6.49-7.97) per 100 person-years during the first year of ART. ART baseline factors were associated with LTFU, but were non-optimal predictors. A model including ART process-related factors such as follow-up behaviors and physical health status had an area under the receiver operating characteristic curve of 73.4% for predicting LTFU. Therefore, the medical records of follow-up visits can be used to identify patients with a high risk of LTFU and allow interventions to be implemented proactively.

Incidence rate, predictors and outcomes of interruption of HIV care: nationwide results from the Belgian HIV cohort

Objectives

We aimed to study the incidence rate, predictors and outcomes of HIV care interruption (HCI) in Belgium.

Methods

We analysed data for adult patients with at least two HIV care records in the Belgian HIV cohort between 1 January 2007 and 31 December 2016. An HCI episode was defined as 1 year without an HIV care record. The HCI incidence rate was analysed using Poisson regression, return to HIV care using a cumulative incidence function with death as a competing risk, and viral load (VL) status upon return to HIV care using logistic regression.

Results

We included 16 066 patients accounting for 78 625 person‐years of follow‐up. The incidence rate of HCI was 5.3/100 person‐years [95% confidence interval (CI) 5.1–5.4/100 person‐years]. The incidence of return to HIV care after HCI was estimated at 77.5% (95% CI 75.7–79.2%). Of those who returned to care, 43.7% had a VL ≤ 200 HIV‐1 RNA copies/mL, suggesting care abroad or suboptimal care (without an HIV‐related care record) in Belgium during the HCI, and 56.3% returned without controlled VL and were therefore considered as having experienced a real gap in HIV care; they represented 2.3/100 person‐years of follow‐up. Factors individually associated with HCI were no antiretroviral therapy (ART) uptake, lower age, injecting drug use, non‐Belgian nationality, male gender, not being a man who has sex with men, a shorter time since HIV diagnosis, no high blood pressure and CD4 count < 350 cells/µL.

Conclusions

This study highlights the need to investigate return to care and viral status at return, to better understand HCI. Identified predictors can help health care workers to target patients at higher risk of HCI for awareness and support.

High frequency of new recombinant forms in HIV-1 transmission networks demonstrated by full genome sequencing

The HIV-1 epidemic in Belgium is primarily driven by MSM. In this patient population subtype B predominates but an increasing presence of non-B subtypes has been reported. We aimed to define to what extent the increasing subtype heterogeneity in a high at risk population induces the formation and spread of new recombinant forms. The study focused on transmission networks that reflect the local transmission to an important extent. One hundred and five HIV-1 transmission clusters were identified after phylogenetic analysis of 2849 HIV-1 pol sequences generated for the purpose of baseline drug resistance testing between 2013 and 2017. Of these 105 clusters, 62 extended in size during the last two years and were therefore considered as representing ongoing transmission. These 62 clusters included 774 patients in total. From each cluster between 1 and 3 representative patients were selected for near full-length viral genome sequencing. In total, the full genome sequence of 101 patients was generated. Indications for the presence of a new recombinant form were found for 10 clusters. These 10 clusters represented 105 patients or 13.6% of the patients covered by the study. The findings clearly show that new recombinant strains highly contribute to local transmission, even in an epidemic that is largely MSM and subtype B driven. This is an evolution that needs to be monitored as reshuffling of genome fragments through recombination may influence the transmissibility of the virus and the pathology of the infection. In addition, important changes in the sequence of the viral genome may challenge the performance of tests used for diagnosis, patient monitoring and drug resistance analysis.

Estimates of the HIV undiagnosed population in Belgium reveals higher prevalence for MSM with foreign nationality and for geographic areas hosting big cities

Introduction

Increasing our knowledge on geographic areas and key populations most affected by HIV is essential to improve prevention and care and to ensure a more focused HIV response. Here, we estimated the prevalence of undiagnosed HIV infections in Belgium and its distribution across geographic areas and exposure groups.

Methods

We used surveillance data on newly diagnosed HIV cases and a previously developed back‐calculation model to estimate number and prevalence rates (per 10000) of undiagnosed HIV infections by exposure group at national and subnational levels. Belgium consists of three regions: Flanders, Brussels‐Capital Region and Wallonia. We produced estimates for Brussels‐Capital Region and Wallonia. For Flanders, we produced estimates for two sub‐regional areas: the province of Antwerp and the other provinces, because Antwerp is the second largest city after Brussels. Population sizes were determined using data from the Belgian Statistical Office and surveys on sexual behaviour and drug use.

Results

In Belgium, in 2015, an estimated 2818 (95% confidence interval: 2494 to 3208) individuals were living with undiagnosed HIV, that is, 15% of individuals living with HIV. The Brussels‐Capital Region and the province of Antwerp, which host the two biggest cities, accounted for ~60% of the undiagnosed infections, and had the highest undiagnosed prevalence rates per 10000: 12.0 (9.4 to 15.3) and 7.4 (5.6 to 9.8) respectively. Individuals with foreign nationality accounted for 56% of the total number of undiagnosed infections, and were the most affected populations in all areas in terms of undiagnosed prevalence rates. Specifically, men who have sex with men (MSM) with non‐European nationality were the most affected population in the province of Antwerp (853.4 (408.2 to 1641.9) undiagnosed infections per 10000), the Brussels‐Capital Region (543.9 (289.1 to 1019.1)), and the other provinces of Flanders (691.7 (235.5 to 1442.2)), while in Wallonia, it was heterosexual women with Sub‐Saharan African nationality (132.2 (90.6 to 178.5)).

Conclusions

Geographic areas hosting the biggest cities in Belgium accounted for the vast majority of undiagnosed HIV infections and individuals with foreign nationality were the most affected, especially MSM with non‐European nationality. This should be accounted for when tailoring prevention and testing programs. Furthermore, MSM with foreign nationality require more attention in Belgium, and certainly more generally in Europe.

The role of mobility in sexual risk behaviour and HIV acquisition among sub-Saharan African migrants residing in two European cities

BACKGROUND

Migrants from high endemic countries accounted for 18% of newly diagnosed HIV infections in Europe in 2017. Knowledge on the link between HIV risk and post-migration travels and their impact on HIV acquisition is scarce, but critical to inform prevention. This study aims to explore risky sexual behaviour and HIV-acquisition among sub-Saharan African migrants, and to assess post-migration mobility as a determinant of sexual risk behaviour.

METHODS

Data from two cross-sectional bio-behavioural surveys to assess HIV-prevalence conducted in Lisbon and Antwerp were analysed to explore migration-related characteristics, travel patterns, and sexual risk taking in the host country and abroad. Bi- and multivariate associations were estimated through adjusted odds ratios and 95% confidence intervals; multivariable logistic regression determined factors associated with condomless sexual intercourse.

RESULTS

Among N = 1508 participants above 18 years (58% males), 68% travelled post-migration (49.2% reported intercourse abroad). The overall proportion of condomless sex at last sexual intercourse was high (68.1%). The odds of condomless sex in the host country was five times higher when the last sexual intercourse abroad was also condomless [OR:5.32; 95%CI:2.98-9.25]. About half of the travellers reported concurrency, i.e. a regular partner in the host country while having other sexual partners abroad. Almost three percent of the participants reported being HIV+, but 5% had a reactive HIV test-result, with similar proportions among travellers and non-travellers. Also, among the n = 75 participants with reactive HIV test-results, condomless sex occurred (n = 40) and was associated with mobility.

CONCLUSIONS

Sub-Saharan African migrants are mobile and engage in sexual risk behaviours in the countries of residence and while travelling, increasing risk of post-migration HIV-acquisition. A transnational perspective on HIV prevention and sexual health promotion is needed for effectively reducing migrants' HIV risk related to their mobility.

Exploring HIV-1 Transmission Dynamics by Combining Phylogenetic Analysis and Infection Timing

HIV-1 pol sequences obtained through baseline drug resistance testing of patients newly diagnosed between 2013 and 2017 were analyzed for genetic similarity. For 927 patients the information on genetic similarity was combined with demographic data and with information on the recency of infection. Overall, 48.3% of the patients were genetically linked with 11.4% belonging to a pair and 36.9% involved in a cluster of ≥3 members. The percentage of early diagnosed (≤4 months after infection) was 28.6%. Patients of Belgian origin were more frequently involved in transmission clusters (49.7% compared to 15.3%) and diagnosed earlier (37.4% compared to 12.2%) than patients of Sub-Saharan African origin. Of the infections reported to be locally acquired, 69.5% were linked (14.1% paired and 55.4% in a cluster). Equal parts of early and late diagnosed individuals (59.9% and 52.4%, respectively) were involved in clusters. The identification of a genetically linked individual for the majority of locally infected patients suggests a high rate of diagnosis in this population. Diagnosis however is often delayed for >4 months after infection increasing the opportunities for onward transmission. Prevention of local infection should focus on earlier diagnosis and protection of the still uninfected members of sexual networks with human immunodeficiency virus (HIV)-infected members.

Persistent disparities in antiretroviral treatment (ART) coverage and virological suppression across Europe, 2004 to 2015

Background: Direct comparisons between countries in core HIV care parameters are often hampered by differences in data collection. Aim: Within the EuroSIDA study, we compared levels of antiretroviral treatment (ART) coverage and virological suppression (HIV RNA < 500 copies/mL) across Europe and explored temporal trends. Methods: In three cross-sectional analyses in 2004–05, 2009–10 and 2014–15, we assessed country-specific percentages of ART coverage and virological suppression among those on ART. Temporal changes were analysed using logistic regression. Results: Overall, the percentage of people on ART increased from 2004–05 (67.8%) to 2014–15 (78.2%), as did the percentage among those on ART who were virologically suppressed (75.2% in 2004–05, 87.7% in 2014–15). However, the rate of improvement over time varied significantly between regions (p < 0.01). In 2014–15, six of 34 countries had both ART coverage and virological suppression of above 90% among those on ART. The pattern varied substantially across clinics within countries, with ART coverage ranging from 61.9% to 97.0% and virological suppression from 32.2% to 100%. Compared with Western Europe (as defined in this study), patients in other regions were less likely to be virologically suppressed in 2014–15, with the lowest odds of suppression (adjusted odds ratio = 0.16; 95% confidence interval (CI): 0.13–0.21) in Eastern Europe. Conclusions: Despite overall improvements over a decade, we found persistent disparities in country-specific estimates of ART coverage and virological suppression. Underlying reasons for this variation warrant further analysis to identify a best practice and benchmark HIV care across EuroSIDA.

HIV outcomes among migrants from low-income and middle-income countries living in high-income countries: a review of recent evidence

PURPOSE OF REVIEW

Migrants living in high-income countries are disproportionately affected by HIV infection and frequently have characteristics associated with poor HIV clinical outcomes. HIV epidemiology among migrants is influenced by changes in migration patterns and variations in transmission risk behaviors. Here we review the recently published literature on known HIV outcomes among migrants from low-income and middle-income countries living in high-income countries.

RECENT FINDINGS

High proportions of migrants acquire HIV after migration, and this group frequently presents to care late. Once established in care, migrants are often more likely to experience worse HIV treatment outcomes compared with native populations. Multiple individual and structural factors influence HIV diagnosis and treatment outcomes among migrants, including disruption of social networks, increased sexual risk behaviors, communication barriers, limited access to care, and stigma. Few studies have examined interventions targeted at improving HIV outcomes among migrants.

SUMMARY

Stigma and limited access to care appear to be primary drivers of poor HIV outcomes among migrants in high-income countries. Addressing these disparities is limited by difficulties in identifying and monitoring this population as well as a lack of evidence regarding appropriate interventions for migrants living with HIV. Improving outcomes for this group requires interventions that are specifically targeted at this marginalized and growing population.

Factors associated with delayed linkage to care following HIV diagnosis in the WHO European Region

OBJECTIVES

To describe linkage to HIV care following diagnosis in Europe and to identify factors associated with delayed linkage.

METHODS

We analysed data of adults (aged ≥ 15 years) diagnosed with HIV from 2010 to 2014 in 31 European countries. Linkage to care was calculated using the time between HIV diagnosis and first CD4 count. Linkage was considered delayed if the CD4 count was taken more than 3 months after diagnosis. Logistic regression was used to determine factors for delayed linkage.

RESULTS

Of the 120 129 adults diagnosed from 2010 to 2014, 4560 were previously diagnosed elsewhere, 808 died within 3 months of diagnosis and 54 731 people were missing CD4 count and/or date information. Among the 60 030 people included, linkage to care within 3 months was 96%. A lower bound (LB) for this was 55%, when those missing CD4 data were assumed not to be linked. Prompt linkage varied significantly by region [Western: 97% (LB: 65%); Central: 90% (LB: 65%); Eastern: 91% (LB: 11%)] and risk group. In multivariable analysis, delayed linkage to care was associated with: acquiring HIV through injecting drug use/heterosexual contact, being diagnosed in Central/Eastern Europe and having a first CD4 count > 200 cells/μL. People of older age at diagnosis and those diagnosed after 2011 were more likely to be linked promptly. Associations differed by region.

CONCLUSIONS

Among those with CD4 data available, linkage to care is prompt. However, HIV surveillance must be strengthened and data quality improved, particularly in Eastern Europe. Our findings highlight disparities in care access and significant differences between regions.

Earlier Initiation of Antiretroviral Treatment Coincides With an Initial Control of the HIV-1 Sub-Subtype F1 Outbreak Among Men-Having-Sex-With-Men in Flanders, Belgium

Human immunodeficiency virus type 1 (HIV-1) non-B subtype infections occurred in Belgium since the 1980s, mainly amongst migrants and heterosexuals, whereas subtype B predominated in men-having-sex-with-men (MSM). In the last decade, the diagnosis of F1 sub-subtype in particular has increased substantially, which prompted us to perform a detailed reconstruction of its epidemiological history. To this purpose, the Belgian AIDS Reference Laboratories collected HIV-1 pol sequences from all sub-subtype F1-infected patients for whom genotypic drug resistance testing was requested as part of routine clinical follow-up. This data was complemented with HIV-1 pol sequences from countries with a high burden of F1 infections or a potential role in the global origin of sub-subtype F1. The molecular epidemiology of the Belgian subtype F1 epidemic was investigated using Bayesian phylogenetic inference and transmission dynamics were characterized based on birth-death models. F1 sequences were retained from 297 patients diagnosed and linked to care in Belgium between 1988 and 2015. Phylogenetic inference indicated that among the 297 Belgian F1 sequences, 191 belonged to a monophyletic group that mainly contained sequences from people likely infected in Belgium (OR 26.67, 95% CI 9.59–74.15), diagnosed in Flanders (OR 7.28, 95% CI 4.23–12.53), diagnosed at a recent stage of infection (OR 7.19, 95% CI 2.88-17.95) or declared to be MSM (OR 34.8, 95% CI 16.0–75.6). Together with a Spanish clade, this Belgian clade was embedded in the genetic diversity of Brazilian subtype F1 strains and most probably emerged after one or only a few migration events from Brazil to the European continent before 2002. The origin of the Belgian outbreak was dated back to 2002 (95% higher posterior density 2000–2004) and birth-death models suggested that its extensive growth had been controlled (R_e < 1) by 2012, coinciding with a time period where delay in antiretroviral treatment initiation substantially declined. In conclusion, phylogenetic reconstruction of the Belgian HIV-1 sub-subtype F1 epidemic illustrates the introduction and substantial dissemination of viral strains in a geographically restricted risk group that was most likely controlled by effective treatment as prevention.

Infectious diseases at different stages of migration: an expert review

BACKGROUND

Human migration is increasing in magnitude and scope. The majority of migrants arriving in high-income countries originate from countries with a high prevalence of infectious diseases. The risk and burden of infectious diseases are not equally distributed among migrant groups and vary with migration stage.

METHODS

A broad literature review was conducted on the drivers for infectious diseases and associated health outcomes among migrants across different stages of migration. The aim was to provide practitioners with an overview of the key infectious disease risks at each stage to guide health promotion strategies.

RESULTS

A complex interaction of factors leads to infectious diseases and associated poor health outcomes among migrants. The most important drivers are the epidemiology of infectious diseases in their countries of origin, the circumstances and conditions of the migration journey and barriers accessing healthcare post-arrival. During the recent large waves of forced migration into Europe, the primary health concerns on arrival were psychological, traumatic and chronic non-communicable diseases. In the early settlement period, crowded and unhygienic living conditions in reception camps facilitated outbreaks of respiratory, gastrointestinal, skin infections and vaccine preventable diseases. After re-settlement, undetected and untreated latent infections due to tuberculosis, viral hepatitis, HIV, chronic helminthiasis and Chagas' disease led to poor health outcomes. Migrants are disproportionally affected by preventable travel-related diseases such as malaria, typhoid and hepatitis due to poor uptake of pre-travel prophylaxis and vaccination. Infectious diseases among migrants can be decreased at all migration stages with health promotion strategies adapted to their specific needs and delivered in a linguistically and culturally sensitive manner.

CONCLUSIONS

Tailored health promotion and screening approaches and accessible and responsive health systems, regardless of legal status, will be needed at all migration stages to limit the burden and transmission of infectious diseases in the migrant population.

Trends in HIV care cascade engagement among diagnosed people living with HIV in Ontario, Canada: A retrospective, population-based cohort study

BACKGROUND

The HIV cascade is an important framework for assessing systems of care, but population-based assessment is lacking for most jurisdictions worldwide. We measured cascade indicators over time in a population-based cohort of diagnosed people living with HIV (PLWH) in Ontario, Canada.

METHODS

We created a retrospective cohort of diagnosed PLWH using a centralized laboratory database with HIV diagnostic and viral load (VL) test records linked at the individual-level. Individuals enter the cohort with record of a nominal HIV-positive diagnostic test or VL test, and remain unless administratively lost to follow-up (LTFU, >2 consecutive years with no VL test and no VL test in later years). We calculated the annual percent of diagnosed PLWH (cohort individuals not LTFU) between 2000 and 2015 who were in care (≥1 VL test), on ART (as documented on VL test requisition) or virally suppressed (<200 copies/ml). We also calculated time from diagnosis to linkage to care and viral suppression among individuals newly diagnosed with HIV. Analyses were stratified by sex and age. Upper/lower bounds were calculated using alternative indicator definitions.

RESULTS

The number of diagnosed PLWH increased from 8,859 (8,859-11,389) in 2000 to 16,110 (16,110-17,423) in 2015. Over this 16-year period, the percent of diagnosed PLWH who were: in care increased from 81% (63-81%) to 87% (81-87%), on ART increased from 55% (34-60%) to 81% (70-82%) and virally suppressed increased from 41% (23-46%) to 80% (67-81%). Between 2000 and 2014, the percent of newly diagnosed individuals who linked to care within three months of diagnosis or achieved viral suppression within six months of diagnosis increased from 67% to 82% and from 22% to 42%, respectively. Estimates were generally lower for females and younger individuals.

DISCUSSION

HIV cascade indicators among diagnosed PLWH in Ontario improved between 2000 and 2015, but gaps still remain-particularly for younger individuals.

Phylogenetic analysis of the Belgian HIV-1 epidemic reveals that local transmission is almost exclusively driven by men having sex with men despite presence of large African migrant communities

To improve insight in the drivers of local HIV-1 transmission in Belgium, phylogenetic, demographic, epidemiological and laboratory data from patients newly diagnosed between 2013 and 2015 were combined and analyzed. Characteristics of clustered patients, paired patients and patients on isolated branches in the phylogenetic tree were compared. The results revealed an overall high level of clustering despite the short time frame of sampling, with 47.6% of all patients having at least one close genetic counterpart and 36.6% belonging to a cluster of 3 or more individuals. Compared to patients on isolated branches, patients in clusters more frequently reported being infected in Belgium (95.1% vs. 47.6%; p < 0.001), were more frequently men having sex with men (MSM) (77.9% vs. 42.8%; p < 0.001), of Belgian origin (68.2% vs. 32.9%; p < 0.001), male gender (92.6% vs. 65.8%; p < 0.001), infected with subtype B or F (87.8% vs. 43.4%; p < 0.001) and diagnosed early after infection (55.4% vs. 29.0%; p < 0.001). Strikingly, Sub-Saharan Africans (SSA), overall representing 27.1% of the population were significantly less frequently found in clusters than on individual branches (6.0% vs. 41.8%; p < 0.001). Of the SSA that participated in clustered transmission, 66.7% were MSM and this contrasts sharply with the overall 12.0% of SSA reporting MSM. Transmission clusters with SSA were more frequently non-B clusters than transmission clusters without SSA (44.4% versus 18.2%). MSM-driven clusters with patients of mixed origin may account, at least in part, for the increasing spread of non-B subtypes to the native MSM population, a cross-over that has been particularly successful for subtype F and CRF02_AG. The main conclusions from this study are that clustered transmission in Belgium remains almost exclusively MSM-driven with very limited contribution of SSA. There were no indications for local ongoing clustered transmission of HIV-1 among SSA.

Linkage to HIV care following diagnosis in the WHO European Region: A systematic review and meta-analysis, 2006-2017

BACKGROUND

Timely linkage to care after HIV diagnosis is crucial as delayed access can result in poor patient outcomes. The aim of this systematic review was to synthesise the evidence to achieve a better understanding of what proportion of patients are linked to care and what factors impact linkage.

METHODS

Systematic searches were run in six databases up to the end of February 2017. The grey literature was also reviewed. Inclusion criteria were: sample size ≥50 people (aged ≥15), from the WHO European Region, published 2006-2017 and in English. Linkage to care was defined as a patient seen for HIV care after diagnosis. Study selection, data extraction and quality assurance were performed by two independent reviewers. Random-effects meta-analysis was carried out to summarise linkage to care within three months of diagnosis.

RESULTS

Twenty-four studies were included; 22 presented linkage to care data and seven examined factors for linkage. Linkage among 89,006 people in 19 countries was captured. Meta-analysis, restricted to 12 studies and measuring prompt linkage within three months, gave a pooled estimate of 85% (95% CI: 75%-93%). Prompt linkage was higher in studies including only people in care (94%; 95% CI: 91%-97%) than in those of all new diagnoses (71%; 95% CI: 50%-87%). Heterogeneity was high across and within strata (>99%). Factors associated with delaying or not linking to care included: acquiring HIV through heterosexual contact/injecting drug use, younger age at diagnosis, lower levels of education, feeling well at diagnosis and diagnosis outside an STI clinic.

CONCLUSION

Overall, linkage to care was high, though estimates were lower in studies with a high proportion of people who inject drugs. The high heterogeneity between studies made it challenging to synthesise findings. Studies should adopt a standardised definition with a three month cut-off to measure prompt linkage to care to ensure comparability.

Health and budget impact of combined HIV prevention - first results of the BELHIVPREV model

OBJECTIVES

We developed a pragmatic modelling approach to estimate the impact of treatment as prevention (TasP); outreach testing strategies; and pre-exposure prophylaxis (PrEP) on the epidemiology of HIV and its associated pharmaceutical expenses.

METHODS

Our model estimates the incremental health (in terms of new HIV diagnoses) and budget impact of two prevention scenarios (outreach+TasP and outreach+TasP+PrEP) against a 'no additional prevention' scenario. Model parameters were estimated from reported Belgian epidemiology and literature data. The analysis was performed from a healthcare payer perspective with a 15-year-time horizon. It considers subpopulation differences, HIV infections diagnosed in Belgium having occurred prior to migration, and the effects of an ageing HIV population.

RESULTS

Without additional prevention measures, the annual number of new HIV diagnoses rises to over 1350 new diagnoses in 2030 as compared to baseline, resulting in a budget expenditure of €260.5 million. Implementation of outreach+TasP and outreach+TasP+PrEP results in a decrease in the number of new HIV diagnoses to 865 and 663 per year, respectively. Respective budget impacts decrease by €20.6 million and €33.7 million.

CONCLUSION

Foregoing additional investments in prevention is not an option. An approach combining TasP, outreach and PrEP is most effective in reducing the number of new HIV diagnoses and the HIV treatment budget. Our model is the first pragmatic HIV model in Belgium estimating the consequences of a combined preventive approach on the HIV epidemiology and its economic burden assuming other prevention efforts such as condom use and harm reduction strategies remain the same.

Immunological and virological response to antiretroviral treatment in migrant and native men and women in Western Europe; is benefit equal for all?

OBJECTIVES

The aim of the study was to evaluate differences in immunovirological response to combination antiretroviral therapy (cART) in migrant and native men and women within a European collaboration of HIV cohorts Collaboration of Observational HIV Epidemiological Research in Europ (COHERE) in EuroCoord, 2004-2013.

METHODS

Migrants were defined as those with geographical origin (GO) different from the reporting country and were grouped as originating from Western Europe and Western Countries (WEWC), Eastern Europe (EE), North Africa and the Middle East (NAME), sub-Saharan Africa (SSA), Latin America (LA), Caribbean (CRB) and Asia/Oceania (ASIA/OCE). Native (NAT) individuals were defined as those originating from the reporting country. CD4 cell counts were modelled using piecewise linear mixed-effects models with two slopes, whereas models to estimate subdistribution hazard ratios (sHRs) were used for time to virological response (VR) (i.e. time from cART initiation to the first of two successive HIV RNA measurements < 400 HIV-1 RNA copies/ml).

RESULTS

Of 32 817 individuals, 25 799 (78.6%) were men. The percentage of migrants was higher in women (48.9%) than in men (21.2%) and migrants from SSA accounted for the largest migrant group (29.9% in men and 63.3% in women). Migrant men and women from SSA started at lower CD4 cell counts than NAT individuals, which remained lower over time. VR was ≥ 85% at 12 months for all groups except CRB women (77.7%). Compared with NAT men and women, lower VR was experienced by NAME [sHR 0.91; 95% confidence interval (CI) 0.86-0.97] and SSA (sHR 0.88; 95% CI 0.82-0.95) men and CRB (sHR 0.77; 85% CI 0.67-0.89) women, respectively.

CONCLUSIONS

Immunovirological response to cART in Western Europe varies by GO and sex of patients. ART benefits are not equal for all, underlining the point that efforts need to prioritize those most in need.

The Human Immunodeficiency Virus Continuum of Care in European Union Countries in 2013: Data and Challenges

BACKGROUND.

The Joint United Nations Programme on HIV/AIDS (UNAIDS) has set a "90-90-90" target to curb the human immunodeficiency virus (HIV) epidemic by 2020, but methods used to assess whether countries have reached this target are not standardized, hindering comparisons.

METHODS.

Through a collaboration formed by the European Centre for Disease Prevention and Control (ECDC) with European HIV cohorts and surveillance agencies, we constructed a standardized, 4-stage continuum of HIV care for 11 European Union countries for 2013. Stages were defined as (1) number of people living with HIV in the country by end of 2013; (2) proportion of stage 1 ever diagnosed; (3) proportion of stage 2 that ever initiated ART; and (4) proportion of stage 3 who became virally suppressed (≤200 copies/mL). Case surveillance data were used primarily to derive stages 1 (using back-calculation models) and 2, and cohort data for stages 3 and 4.

RESULTS.

In 2013, 674500 people in the 11 countries were estimated to be living with HIV, ranging from 5500 to 153400 in each country. Overall HIV prevalence was 0.22% (range, 0.09%-0.36%). Overall proportions of each previous stage were 84% diagnosed, 84% on ART, and 85% virally suppressed (60% of people living with HIV). Two countries achieved ≥90% for all stages, and more than half had reached ≥90% for at least 1 stage.

CONCLUSIONS.

European Union countries are nearing the 90-90-90 target. Reducing the proportion undiagnosed remains the greatest barrier to achieving this target, suggesting that further efforts are needed to improve HIV testing rates. Standardizing methods to derive comparable continuums of care remains a challenge.

Differences between migrants and Spanish-born population through the HIV care cascade, Catalonia: an analysis using multiple data sources

Migrants are considered a key group at risk for HIV infection. This study describes differences between migrants and the Spanish-born population as they progress through the HIV care cascade in Catalonia, Spain. This study found that among people reached by prevention activities, migrants had a higher number of barriers to access HIV testing services than Spanish-born people, driven primarily by shared risk factors. Between 2001 and 2013, 9829 new HIV diagnoses were reported in Catalonia, the proportion of migrants increasing from 24% in 2001 to 41% in 2013. Compared with Spanish-born people, migrants had a higher proportion of women at diagnosis (24·6% vs. 16·7%), and were younger (median age of 33 vs. 37). The most frequent at-risk population was MSM (men who have sex with men) in both migrants and Spanish-born people, (40% and 43%, respectively), although there were significant differences by region of origin. People from sub-Saharan Africa had the highest proportion of late diagnosis (63·7%). Compared with the Spanish-born population, migrants on follow-up had a lower proportion of people on antiretroviral therapy (ART) (93·7% vs. 90·8%, P < 0·001) and with viral suppression (87·2% vs. 82·9%, P < 0·001). Migrants have higher number of barriers to access HIV testing services, lower retention rates and proportions on ART as compared with Spanish-born people, these differences not being uniform between migrants from different regions.

Timing of combined antiretroviral treatment initiation in male and female migrants living with HIV in Western Europe

BACKGROUND

We evaluate differences in timing of cART (combined antiretroviral treatment) initiation by geographical origin in male and female HIV-positive patients in the Collaboration of Observational HIV Epidemiological Research Europe, a large European Collaboration of HIV Cohorts.

METHODS

We included individuals recruited in Western Europe between January 1997 and March 2013, with known geographical origin and at least 1 CD4 cell count measurement while cART-naive. Timing of cART was assessed through modified time-to-event methods, in which a scale of CD4 cell counts was used instead of time, with cART being the outcome. We estimated the median CD4 cell count at cART initiation (estimated CD4 levels at which the probability of having started cART is 50%) using Kaplan-Meier and adjusted hazard ratios of cART initiation using Cox regression.

RESULTS

Of 151 674 individuals, 110 592 (72.9%) were men. Median (95% confidence interval) CD4 cell count falls far below 250 cells/μl in all groups and was lowest in sub-Saharan African [SSA: 161 (158-167)], Caribbean men [161 (150-174)] and in Asian women [Asian Continent and Oceania: 185 (165-197)]. Among men, the adjusted probability of cART initiation was lower in migrants compared with natives, but differences depended on initial CD4 cell count. For example, in the group with more than 500 CD4 at recruitment, they were 45% (36-53%), 30% (17-40%) and 25% (19-30%) lower for Caribbean, Eastern European and SSA men, respectively. In women, no meaningful differences were observed between natives and most migrant groups. However, SSA women had a 31% (24-38%) higher probability of cART initiation when recruited at a CD4 more than 500 cells/μl and 9% (4-14%) lower when recruited at CD4 less than 100 cells/μl.

CONCLUSION

Most migrant men initiate cART at lower CD4 cell count than natives, whereas this does not hold for migrant women.

Migration and infectious diseases

BACKGROUND

Infectious diseases still represent an important cause of morbidity and mortality among foreign-born individuals. The rising migration flows towards Europe throughout the last few years are raising renewed concerns about management issues and the potential associated risk for the native population.

AIMS

To discuss the health implications and challenges related to the four phases of migration, from first arrival to stable resettlement.

SOURCES

Scientific literature and relevant statistical reports.

CONTENT

Although infectious diseases are not a health priority at first arrival, a syndromic screening to identify the most common communicable conditions (pulmonary tuberculosis above all) should be promptly conducted. Reception centres where asylum seekers are gathered after arrival may be crowded, so favouring epidemic outbreaks, sometimes caused by incomplete vaccine coverage for preventable diseases. After resettlement, the prevalence of some chronic infections such as human immunodeficiency virus, viral hepatitis or tuberculosis largely reflects the epidemiological pattern in the country of origin, with poor living conditions being an additional driver. Once resettled, migrants usually travel back to their country of origin without seeking pre-travel advice, which results in a high incidence of malaria and other infections.

IMPLICATIONS

Although infectious diseases among migrants are known to have a negligible impact on European epidemiology, screening programmes need to be implemented and adapted to the different stages of the migratory process to better understand the trends and set priorities for action. Appropriate access to care regardless of the legal status is crucial to improve the health status and prevent the spread of contagious conditions.