Epidemiological changes of acute/recent human immunodeficiency virus type 1 infection in Barcelona, Spain (1997-2015): a prospective cohort study

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Article

Reference

Epidemiological changes of acute/recent human immunodeficiency virus type 1 infection in Barcelona, Spain (1997-2015): a prospective

cohort study

NICOLÁS, D, et al . & Hospital Clinic Acute/Recent HIV Study Group

Abstract

To describe the epidemiology of acute/recent human immunodeficiency virus (HIV) infection over two decades in Barcelona (Spain).

NICOLÁS, D, et al . & Hospital Clinic Acute/Recent HIV Study Group. Epidemiological changes of acute/recent human immunodeficiency virus type 1 infection in Barcelona, Spain (1997-2015):

a prospective cohort study. Clinical Microbiology and Infection , 2019, vol. 25, no. 7, p.

878-884

DOI : 10.1016/j.cmi.2018.10.021 PMID : 30472421

Available at:

http://archive-ouverte.unige.ch/unige:143794

Disclaimer: layout of this document may differ from the published version.

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Original article

Epidemiological changes of acute/recent human immunode ﬁ ciency virus type 1 infection in Barcelona, Spain (1997 e 2015): a prospective cohort study

^*

D. Nicol as

¹^,^y

, J. Ambrosioni

¹^,^y

, E. de Lazzari

¹

, A. Suarez

¹

, C. Manzardo

¹

, F. Agüero

¹

, M.M. Mosquera

²

, J. Costa

²

, C. Ligero

¹

, M. A. Marcos

²

, S. S anchez-Palomino

³

,

E. Fern andez

¹

, M. Plana

³

, S. Yerly

⁴

, J.M. Gatell

¹

, J.M. Mir o

¹^,^*

, the Hospital Clinic Acute/

Recent HIV Study Group

1)Infectious Diseases Service, Hospital Clinic-IDIBAPS, University of Barcelona, Barcelona, Spain

2)Laboratory of Virology, Microbiology Service, Hospital Clinic Barcelona, CIBERehd, University of Barcelona, Barcelona, Spain

3)Retrovirology and Viral Immunopathology Laboratory, AIDS Research Group, IDIBAPS, Hospital Clínic, University of Barcelona, Barcelona, Spain

4)Laboratory of Virology, Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland

a r t i c l e i n f o

Article history:

Received 17 July 2018 Received in revised form 25 October 2018 Accepted 31 October 2018 Available online 22 November 2018 Editor: L. Kaiser

Keywords:

Acute/Recent human immunodeﬁciency virus infection

Cohort

Human immunodeﬁciency virus epidemiology

Human immunodeﬁciency virus infection Primary human immunodeﬁciency virus infection

a b s t r a c t

Objective:To describe the epidemiology of acute/recent human immunodeﬁciency virus (HIV) infection over two decades in Barcelona (Spain).

Methods:Prospective, single-centre cohort including all patients with an acute/recent HIV infection (<180 days) since 1997. Patients were stratiﬁed into four periods. Phylogenetic analysis was performed to determine clusters of transmission.

Results:A total of 346 consecutive acute/recently infected patients were included. The annual proportion of recent infections among total new HIV diagnoses increased over time from 1% (29 out of 1964) to 8%

(112 out of 1474) (p<0.001). Proportion of men who have sex with men (MSM) in the cohort increased from 62% (18 out of 29) to 89% (100 out of 112) (p<0.001). The proportion of migrants showed a non- signiﬁcant increasing trend (24% (7 of 29) to 40% (45 of 112)) likewise the non-B subtype (0% to 22% (22 of 112)). The mean time from infection to diagnosis was 53.6 days (interquartile range (IQR) 50e57), comparable among all periods. Mean time from infection to treatment decreased over the years from 575 (IQR 467e683) to 471 (IQR 394e549) days (p<0.001) without signiﬁcant differences between migrants and non-migrants (133 (IQR 71e411) versus 208 (IQR 90e523) days p 0.089). Almost 50% (152 of 311) of recently infected individuals were included in a cluster of transmission, and 92% (137 of 149) of them were MSM.

Conclusion:The MSM population has progressively grown within acutely/recently infected patients in Barcelona, and is frequently involved in transmission clusters. Although the time between diagnosis and treatment has been reduced, the time between infection and diagnosis still needs to be shortened.

D. Nicolas, Clin Microbiol Infect 2019;25:878

Introduction

Acute infection is frequently deﬁned as that of less than 30 days (pre-serological period), and recent infection as that of<180 days [1,2]. Acute/recent human immunodeﬁciency virus (HIV) infection is symptomatic in around 80% of cases, frequently resembling a mononucleosis-like syndrome [3]. The onset of symptoms co- incides with peak HIV-1 viraemia, which can be as high as 6e7 log₁₀

*Presented in part at the 15th European AIDS Conference, Barcelona, Spain, 21e24 October 2015 and at the HIV Glasgow, Glasgow, UK, 23e26 October 2016.

*Corresponding author. J.M. Miro, Infectious Diseases Service, Hospital Clínic, Villarroel, 170, 08036 Barcelona, Spain.

E-mail address:[email protected](J.M. Miro).

y D. Nicolas and J. Ambrosioni contributed equally to this work.

Contents lists available atScienceDirect

Clinical Microbiology and Infection

j o u r n a l h o m e p a g e : w w w . c l i n i c a l m i c r o b i o l o g y a n d i n f e c t i o n . c o m

https://doi.org/10.1016/j.cmi.2018.10.021

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copies/mL[4]. Due to the high viraemia peak and the unawareness of the diagnosis, the rate of transmission of the virus during the acute/recent phase is very high, and in some cohort studies it has been estimated to account for a 25%e50% of new infections and to present a high proportion of transmission clusters[5e8].

Barcelona has high levels of transient and established foreign populations. Access to testing and care differs between local and foreign men who have sex with men (MSM) [9], but the local transmission patterns among these MSM populations, essential for designing prevention campaigns, are poorly understood. Histori- cally, subtype B has been predominant among MSM infected in Europe, and non-B subtypes more frequent in heterosexuals and migrant MSM [10]. However, increases have been recently described in our local context in the proportion of non-B infections among Spanish MSM with acute/recent infection and the proportion of migrants infected with B subtype, leading to the hypothesis that local transmission occurs not only from migrants to native MSM before diagnosis, but also from native MSM to immigrants who arrived uninfected[11].

The aim of this study was to present the epidemiological and clinical characteristics and the temporal trends for the past two decades of a large single-centre cohort of individuals with acute/

recent infection in Barcelona.

Methods Study population

The‘Hospital Clinic Acute/Recent HIV Infection Cohort’com- prises 346 consecutive patients between April 1997 and December 2015. Hospital Clinic is a public, tertiary teaching hospital which serves 560 000 people in the metropolitan area of Barcelona. The catchment area has remained unchanged during the study period.

Approximately 5000 HIV-positive patients are on active follow up and more than 90% are taking antiretroviral therapy (ART). All the enrolled patients were treatment naive and presented<180 days of HIV infection defined by one of the following: a negative ELISA with a detectable viral load or a positive p24 antigen, a positive ELISA with a negative, an indeterminate or incomplete Western blot or a documented negative test in the preceding 6 months[3]. For the phylogenetic analysis, patients with a reactive detuned assay (positive specimens tested using a modified version of the Viro- nostika HIV-1 EIA (bioMerieux, Durham, NC, USA) to render it less sensitive)[12,13]were also included (n¼81, total analysed patients n ¼ 311). Patients were actively questioned and examined for clinical signs and symptoms of seroconversion at thefirst clinical visit. Clinical follow up and blood samples were obtained at diagnosis and at the time of ART initiation, and every 6 months thereafter.

Participants were classiﬁed into four groups according to the date of infection: 1997e2001, 2002e06, 2007e11 and 2012e15.

Virological analyses

HIV serology was determined using a microparticle enzyme immunoassay (AxSYM; Abbott Laboratories, Chicago, IL, USA) and conﬁrmed by line immunoassay (Inno-LIA HIV I/II Scor; , Inno- genetics, Ghent, Belgium). Viraemia was measured using a Cobas Amplicor Monitor (Roche Molecular Systems, Branchburg, NJ, USA) or a Versant HIV-1 RNA 1.0 Assay kPCR (Siemens Health- care, Erlangen, Germany) with limits of detection of 50 and 37 copies/mL, respectively. HIV-1 subtype characterization wasﬁrst performed using the REGA HIV-1 Subtyping Tool of the Stanford database. For the phylogenetic analysis, sequences corresponding to the baseline genotypic resistance test were used. Phylogenetic

inferences were performed using the Neighbour-Joining algo- rithm under the Kimura two-parameter nucleotide substitution model with bootstrap. Bootstrap values of90% were deﬁned for cluster assignment. Clusters of two or more sequences were considered.

Statistical analysis

Summary statistics of quantitative characteristics were presented with mean and standard deviation (SD) or median and interquartile range (IQR) and compared between groups with analysis of variance or KruskaleWallis tests, as appropriate. Quali- tative variables were described with absolute frequency and percentage and compared between groups with chi-squared or Fisher's exact tests. The Poisson regression model was used to assess the proportion of MSM among acute/recent infections over time and acute/recent infections with respect to total new diagnoses. Multi- nomial logistic regression for Fiebig stage (IeIII, IVeV or IV). For continuous dependent variables (i.e. CD4 cell count and viral load) trends over time were estimated using linear regression model, whereas for limited dependent variables (e.g. duration between diagnosis and ART initiation and between infection and diagnosis) Tobit regression was estimated. All tests were two-tailed with conﬁdence levels of 95%. Data were collected in an SPSSﬁle and analysed using STATA(StataCorp. 2013; Stata: Release 13, Statistical Software, College Station, TX, USA) (see Supplementary material for more information on statistical methodology).

Ethical issues

The‘Hospital Clinic Acute/Recent HIV Infection Cohort’has been approved by the Institutional Review Board of the Hospital Clinic of Barcelona, Spain. All patients signed the informed consent form.

Results

During the study period (1997e2015), our hospital was attended by 7077 newly infected HIV patients, of whom 364 (5%) had acute/

recent infection. Over the years, the proportion of the acute/recent HIV infection with respect to the new HIV diagnosis in our centre increased progressively from 1% (29 out of 1964) to 8% (112 out of 1474) (p<0.001) (Fig. 1).

Demographic characteristics

Demographic characteristics are shown inTable 1. Most patients in the cohort were men (93%) and median age was 33 years (IQR 27e39). The main route of transmission was sex between men (87%) in all periods. Nevertheless, in thefirst period, intravenous drug use represented 24% of cases, which decreased to<1% in the last period (p<0.001). Regarding patients' origins, 37% of the cohort were migrants, with South America being the most frequent origin (22%). Throughout the periods, the proportion of migrant patients increased progressively from 24% in thefirst period to 40% in the last. We also observed a progressive, although not significant, increase in HIV-1 non-B subtypes from 15% in 2002e06 to 22% in 2012e15.

At the time of HIV diagnosis, 5% presented co-infection with hepatitis C virus. Positive hepatitis C virus serology decreased from 24% during the ﬁrst period of diagnosis, to only 2% of patients during the last period (p <0.001). Regarding syphilis, 13% of patients presented a positive VDRL (Venereal Disease Research Lab- oratory) test at the time of HIV diagnosis, and this percentage remained stable during the four periods.

D. Nicolas et al. / Clinical Microbiology and Infection 25 (2019) 878e884 879

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Acute/recent HIV infection clinical characteristics

Patients were classiﬁed according to Fiebig classiﬁcation at the time of diagnosis [14]. At that time, 19% presented a negative Western blot (Fiebig stages IeIII), 16% an indeterminate test and 27% an incomplete Western blot (lacking the p31 band). The proportion of Fiebig stages remained stable over the study periods. The mean time from the estimated date of infection to diagnosis was 53.6 days (IQR 50e57) and, although variations among the periods were observed, there was no downward trend over time (Fig. 2a).

No differences were observed between migrants and the Spanish population in terms of time to diagnosis.

In our cohort, 259 patients (65%) presented a symptomatic acute/

recent infection. The frequency of symptomatic infection decayed from 76% (22 out of 29) to 67% (75 out of 112) between theﬁrst and last periods (p 0.031). The most frequent symptoms were fever (230 patients, 90%), asthenia (136 patients, 52%), lymphadenopathies (93 patients, 35%), myalgia (90 patients, 34%) and odynophagia (71 patients, 28%). Median duration of symptoms from onset was 8 days (IQR 7e15). Neurological symptoms were present in 13 patients (5%) Fig. 1.Proportion and 95% CI of acute/recent infection with respect to new human immunodeﬁciency virus diagnoses by year.

Table 1

Clinical characteristics of the cohort

All (n¼346) 1997e2001 (n¼29)

2002e2006 (n¼56)

2007e2011 (n¼149)

2012e2015 (n¼112)

p

Gender (male) 322 (93%) 22 (76%) 49 (88%) 145 (97%) 106 (95%) <0.001

Origin (migrants) 127 (37%) 7 (24%) 19 (35%) 56 (38%) 45 (40%) 0.439

Age (years) 33.7 33.3 33.2 34.6 34.4 0.164

Transmission <0.001

Men who have sex with men 298 (87%) 18 (62%) 42 (75%) 138 (94%) 100 (89%)

Heterosexuals 29 (8%) 4 (14%) 9 (16%) 5 (3%) 11 (10%)

Intravenous drug users 17 (5%) 7 (24%) 5 (9%) 4 (3%) 1 (1%)

Drug use (parenteral^a) 10 (3%) 5 (18%) 2 (4%) 3 (2%) 0 (0%) 0.001

Non-B subtype 45 (19%) 0 (0%) 2 (15%) 21 (17%) 22 (22%) 0.843

Time from infection to diagnosis (days)^b 54 (36) 52 (37) 52 (31) 57 (41) 50 (31) 0.383

Fiebig stage 0.006

I 1 (0,3%) 0 (0%) 0 (0%) 0 (0%) 1 (1%)

II 37 (11%) 5 (17%) 6 (11%) 20 (13%) 6 (5%)

III 27 (7,7%) 4 (14%) 8 (14%) 10 (7%) 5 (4%)

IV 57 (17%) 7 (24%) 14 (25%) 19 (13%) 17 (15%)

V 94 (27%) 1 (3%) 15 (27%) 36 (24%) 42 (38%)

VI 130 (38%) 12 (41%) 13 (23%) 64 (43%) 41 (37%)

Symptomatic infection (any symptom) 243 (70%) 22 (76%) 48 (86%) 98 (66%) 75 (67%) 0.031

Sexually transmitted infections at diagnosis

Syphilis 43 (13%) 5 (17%) 6 (11%) 16 (11%) 16 (17%) 0.487

Hepatitis C virus positive 16 (5%) 7 (24%) 4 (7%) 3 (2%) 2 (2%) <0.001

aIncluding heroin and cocaine.

bMean (SD).

as et al. / Clinical Microbiology and Infection 25 (2019) 878e884 880

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[15], and 61 patients (18%) required hospital admission during the acute/recent infection, mostly for fever of unknown origin.

Phylogenetic analysis

Baseline genotypic sequences were available for 311 patients. Of them, 152 (49%) were included in clusters of transmission, of whom 92% were MSM. Fifty-three clusters were identiﬁed between two to nine individuals; 45 clusters (121 patients, 79%) involved B subtypes, and eight clusters (35 patients, 23%) involved non-B subtypes.

Of individuals included in B clusters, 35% were migrants (mostly South American and Eastern European), and in non-B clusters, 46%

were Spanish-born. The mean elapsed time between theﬁrst and the last patient diagnosed in each cluster was 28 months (IQR 5e40). Comparisons between patients included and not included in clusters are shown inTable 2. When analysing these data by year of infection, we did not observe a temporal trend in the proportion of acutely/recently infected patients included in clusters (p 0.282) (see details in Supplementary material,Table S9 and S10). The phylogenetic tree is shown in the Supplementary material (Fig. S1).

Fig. 2.Estimated mean time between (a) infection and diagnosis and (b) infection and antiretroviral therapy initiation and 95% CI by year.

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Baseline immunological and virological characteristics

Globally, mean CD4 absolute count and CD4/CD8 ratio at diagnosis were 537 cells/mL (SD 263) and 0.67 (SD 0.48), respectively.

Mean absolute CD4 count at ART initiation was 488 cells/m^{L (SD} 243), and once again no signiﬁcant differences were found over time (predicted and estimated mean by year of infection, p 0.158) (Fig. 3a,b). The median viral load at the time of diagnosis was 4.85 (SD 1.14) log10 copies/mL, also remaining stable over the years (predicted mean model p 0.641).

Antiretroviral treatment

Globally, 340 patients (93.4%) in the cohort started ART at some point, with no differences among the time periods (p 0.097); the median time from the estimated date of infection to the start of ART was 173 days (IQR 79e443). Of these patients, 90 (30%) started treatment in thefirst 3 months. A decrease in the mean time from infection to ART initiation was observed over time, becoming statistically significant when comparing the mean of each of the last 4 years (2012e15) with the mean of the previous years (1997e2011) together (predicted mean by year p<0.001) (Fig. 2b). No statistically significant differences were observed in median time to ART initiation between migrant population and Spanish-born patients (134 days (71e411) versus 208 days (90e523), respectively, p 0.089).

Outcome and follow up

In our cohort, 56 patients (16%) were lost to follow up. Only four patients (1%) died during follow up: one from a solid organ ma- lignancy (squamous cell carcinoma of the lung), one presented a Hodgkin's lymphoma after abandoning ART, one died from a heroin overdose and one committed suicide. Twenty-eight (8.3%) patients changed follow-up centre to another hospital, and 24 (7.4%) were lost to follow up for unknown reasons.

Discussion

The Hospital Clinic Acute/Recent HIV Infection Cohort started enrolling patients in the late 1990s. During the study period, 364 patients were diagnosed during the acute/recent infection, repre- senting 5% of all new diagnoses in our centre. This may be an un- derestimate, however; only those with a documented infection of

<6 months were included in our cohort, and the real proportion may therefore be much higher, as is seen in other cohorts[16]. The proﬁle of the acutely/recently infected patient has varied over time, particularly the transmission path. This change reﬂects more frequent testing among MSM, as it is a highly risk-aware

community with numerous resources for information access and free testing, thanks to the effort of local non-governmental orga- nizations and governments[17]. At the same time, the proportion of intravenous drug users with a new HIV infection has decreased from 24% in theﬁrst period to only one patient (1%) in the last period with a parallel decrease of positive hepatitis C virus serology at diagnosis (from 24% to 2%). These results reﬂect the efforts of combined interventions such as programmes for needle exchange to prevent HIV/hepatitis C virus transmission among intravenous drug users in Barcelona[18]and Spain[19]. It has been observed that the subpopulation of migrant MSM has less access to resources for regular testing and, in cases of infection, rapid treatment[9]. In our cohort no differences were observed in the time to diagnosis or to treatment initiation between migrant and Spanish-born populations, but our study comprised only the minority of acutely/

recently infected migrants.

We observed a non-signiﬁcant rise in the immigrant population included in the cohort over the periods and a non-signiﬁcant rising trend in non-B subtypes of the virus, associated with a greater number of people coming from countries where non-B viruses are more common. In the phylogenetic analysis, a high proportion of patients involved in clusters were detected and almost exclusively among MSM. The B and non-B subtypes are progressively being mixed between local and immigrant MSM populations. As all patients have recent infections, migrants are presumably becoming infected locally. Almost half of the individuals involved in non-B subtype clusters were Spanish-born, suggesting that they too are increasingly being infected by migrants who remain untreated.

These results are consistent with similar studies in other European countries[20,21]and highlight the need for improving prevention campaigns to cut the spread of HIV during acute/recent infection in Barcelona among residents and immigrants. This local situation may, presumably, be similar in other western European cities with large foreign populations, where MSM has become the main risk factor for HIV transmission. In this context, new prevention stra- tegies such as pre-exposure prophylaxis should also be considered globally.

Although the proportion of patients diagnosed with acute/

recent infection increased with time, we did not observe an ex- pected increase in the proportion of early Fiebig stages at diagnosis.

This translates into a higher number of patients tested, but still not early or frequently enough to decrease the duration of the period during which the patient is infected and unaware of the diagnosis.

An important reduction is observed, however, in the time to start ART, which clearly decreases over time according to the changes observed in international guidelines and the evidence that favours early ART initiation[1,2,22]. The proportions of patients initiating treatment in both the first 3 months and the first 6 months increased significantly in the latter periods, reflecting good Table 2

Main characteristics of 311 individuals included in phylogenetic analyses (included and not-included in clusters of transmission)

All Included in clusters Not included in clusters p

n¼311 n¼152 n¼159

Age (years) 33 33 32 0.418

Gender (male) 300 (96%) 149 (98%) 151 (95%) 0.144

Time post-infection at diagnosis (days), median (interquartile range) 54 (30e110) 54 (29e125) 55 (30e103) 0.149

Risk factor (men who have sex with men) 277 (90%) 137 (92%) 140 (88%) 0.153

Origin 0.360

Spanish-born 62.1% 60.3% 63.9%

Other European (west) 10.6% 10.3% 10.8%

Migrants^a 27.3% 29.4% 25.3%

B subtype 218 (84%) 117 (79%) 101 (91%) 0.009

a80% South Americans.

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adherence to the international consensus of offering treatment to every infected patient as soon as possible. Nevertheless, one- quarter of patients still start treatment after 6 months, an important ﬁeld for improvement. Finally, long-term mortality in the cohort was very low, with only four deaths.

Our study has some limitations. First, our cohort represents only the patients diagnosed in one particular area of Barcelona, which might impede the generalization of results to other areas or cities.

Second, in the phylogenetic analysis only sequences from our cohort were analysed; data for other naive patients (not acute/

recently infected) were not included. Finally, data related to recent preventive measures such as pre-exposure prophylaxis and their impact in acute/recent infection epidemiology was not available, as pre-exposure prophylaxis is still only used in a limited manner in Spain.

In conclusion, over nearly two decades, we observed a change in the proﬁle of the acute/recently HIV-infected population. There were no major differences between recently infected migrant and Spanish-born populations but it is likely that our study comprised only a minor population of non-Spanish-born HIV-infected Fig. 3.Estimated mean and 95% CI of (a) baseline CD4^þT-cell count by year of infection and (b) CD4 count at antiretroviral therapy initiation.

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individuals. A large proportion of the patients in the cohort were involved in transmission clusters, and there is still a long way to go to decrease the length of time from infection to diagnosis and to treatment, which is crucial to prevent HIV-1 transmission during acute/recent infection among current key populations such as MSM.

Transparency declaration

The authors declare that they have no conﬂicts of interest.

Funding

This work was supported in part by theFondo de Investigaciones Sanitarias(FIS) grant 04/0363 from the Instituto de Salud Carlos III, Madrid, Spain awarded to JMM. Instituto de Salud Carlos III, Min- isterio de Economía y Competitividad, Madrid (Spain) provided JMM with a personal intensiﬁcation research grant # INT15/00168 during 2016e17. JMM received a personal 80:20 research grant from the Institut d’Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain, during 2017e19. JA developed this work in the frame of aJuan de la Cierva 2012post-doctoral program, Ministerio de Competitividad, Spain. DN developed this work in the frame of a post-residency ScholarshipAjuts a la Recerca‘Josep Font’ 2014, Hospital Clinic, Barcelona, Spain. FA developed this work in the frame of aRio Hortega 2012grant CM12/00195, Ministerio de Competitividad, Spain. C.M. has been the holder of a personal post- doctoral research grant (Pla Estrategic de Recerca i Innovacio en Salut -PERIS- 2016/2020) from the 'Departament de Salut de la Generalitat de Catalunya', Barcelona, Spain. When this article was submitted, JMG started to work in ViiV Healthcare, Barcelona, Spain as Senior Global Medical Director.

Contributions

All the authors contributed to the design and development of the study and to the acquisition, analysis and interpretation of the results. All authors contributed to producing the article, by drafting the work or revising it critically. All authors have had access to the ﬁnal version and have approved it to be published. All authors agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work were properly investigated and resolved.

Appendix A. Supplementary data

Supplementary data to this article can be found online at https://doi.org/10.1016/j.cmi.2018.10.021.

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