EPIDEMIOLOGY AND PREVENTION Country of Birth Does Not Influence Long-term Clinical, Virologic, and Immunological Outcome of HIV-Infected Children Living in the Netherlands: A Cohort Study Comparing Children Born in the Netherlands With Children Born in Sub-Saharan Africa Sophie Cohen, MD,* Ward P. H. van Bilsen, MSc,* Colette Smit, PhD,† Pieter L. A. Fraaij, MD, PhD,‡§ Adilia Warris, MD, PhD,k Taco W. Kuijpers, MD, PhD,* Sibyl P. M. Geelen, MD, PhD,¶ Tom F. W. Wolfs, MD, PhD,¶ Henriette J. Scherpbier, MD, PhD,* Annemarie M. C. van Rossum, MD, PhD,‡ and Dasja Pajkrt, MD, PhD,* on behalf of the Dutch Pediatric HIV Study Group Background: Immigrant HIV-infected adults in industrialized countries show a poorer clinical and virologic outcome compared with native patients. We aimed to investigate potential differences in clinical, immunological, and virologic outcome in Dutch HIV-infected children born in the Netherlands (NL) versus born in Sub-Saharan Africa (SSA) in a national cohort analysis. Methods: We included all HIV-infected children registered between 1996 and 2013. Descriptive statistics, mixed-effects models, and Cox proportional hazard models were used to investigate differences between groups. Results: In total, 319 HIV-infected children were registered. The majority of these children were born in SSA (n = 148, 47%) or NL (n = 113, 36%) and most were black (n = 158, 61%). Children born in NL were diagnosed at a median age of 1.2 years and initiated combination antiretroviral therapy (cART) at a median age of 2.6 years, compared with 3.7 and 5.3 years, respectively, for children born in SSA (HIV diagnosis: P , 0.001; cART initiation: P , 0.001). Despite a lower initial CD4 + T-cell Z-score in children born in SSA, their immunological reconstitution was similar to children from NL. Virologic suppression was achieved in the majority of all cART-treated children (NL: 96%, SSA: 94%). There was no difference in the occurrence or timing of virologic failure. Conclusions: Most immigrant HIV-infected children living in NL were born in SSA. Children born in SSA were diagnosed and initiated cART at an older age than children born in NL. Despite initial differences in CD4 + T-cell counts and HIV viral load, the long-term immunological and virologic response to cART was similar in both groups. Key Words: HIV, country of birth, antiretroviral therapy, children, Netherlands (J Acquir Immune Defic Syndr 2015;68:178–185) INTRODUCTION In 2004, a successful national maternal HIV–screening program was implemented in the Netherlands (NL), which resulted in a profound reduction of perinatal HIV trans- missions. 1 Since then, most new HIV-infected children in NL were immigrants and adopted children from sub-Saharan Africa (SSA), as also reported in several other industrialized countries. 2–6 In the adult population, essential differences in character- istics and outcomes between HIV-infected immigrants and nonimmigrants residing in industrialized countries have been described. In the Swiss cohort, HIV-infected immigrants from SSA were younger, predominantly female, and more fre- quently infected through heterosexual activity as compared with nonimmigrants. 7 African HIV-infected immigrants were Received for publication May 18, 2014; accepted November 5, 2014. From the *Department of Pediatric Haematology, Immunology and Infectious Diseases, Emma Children’s Hospital, Academic Medical Center, Amsterdam, the Netherlands; †Dutch HIV Monitoring Foundation, Amsterdam, the Netherlands; ‡Department of Pediatrics, Division of Infectious Diseases, Immunology and Rheumatology, Erasmus MC University Hospital Rotterdam/Sophia Children’s Hospital, Rotterdam, the Netherlands; §Erasmus MC/Viroscience Lab, Erasmus MC, Rotterdam, the Netherlands; kThe Nijmegen Institute for Infection, Inflammation and Immunity, Radboud University Medical Center, Nijmegen, the Netherlands; and ¶Department of Pediatric Infectious Diseases and Immunology, Wilhelmina Children’s Hospital/University Medical Center, Utrecht, the Netherlands. The authors have no funding or conflicts of interest to disclose. S.C. and W.P.H.v.B. contributed equally to this work. S.C. and D.P. designed the study. H.J.S., D.P., A.M.C.v.R., P.L.A.F., T.F.W.W., A.W., S.P.M.G., and T.W.K. provided the data. S.C. and W.P.H.v.B. performed the statistical analyses in cooperation with C.S. S.C. and W.P.H.v.B. wrote the manuscript under supervision of all co-authors. All authors approved the final version to publish. Members of the Dutch Pediatric HIV Study Group: S. Cohen, T.W. Kuijpers, D. Pajkrt, A. van der Plas, H.J. Scherpbier, A. Weijsenfeld [Amsterdam], E.H. Schölvinck, H.de Groot-de Jonge [Groningen], R. Strik-Albers, M. van der Flier, A. Warris [Nijmegen], G.J.A. Driessen, P.L.A. Fraaij, P. van Jaarsveld, L. van der Knaap, A.M.C. van Rossum [Rotterdam], L. Bont, S.P.M. Geelen, N. Nauta, and T.F.W. Wolfs [Utrecht]. Correspondence to: Sophie Cohen, MD, Department of Paediatric Haematol- ogy, Immunology and Infectious diseases, Emma Children’s Hospital, Academic Medical Center Amsterdam, Meibergdreef 9, Amsterdam 1105AZ, the Netherlands (e-mail: s.cohen@amc.nl). 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