title: Origin and spread of HIV-1 in persons who inject drugs in Bulgaria.
abstract: Increased HIV transmission in persons who inject drugs (PWIDs) has led to subepidemics and outbreaks in several countries in Europe, including Bulgaria. In this study in Bulgaria, we investigate the origin and spatiotemporal evolutionary history of HIV-1 infections in PWIDs and the distribution of antiretroviral resistance mutations and hepatitis co-infections in these populations. We analyzed HIV-1 polymerase sequences available from 117 of 359 PWIDs diagnosed with HIV/AIDS from 1999 to 2011. Of these, 50 (42.7%) were classified as CRF02_AG, 41 (35.0%) CRF01_AE, 12 (10.3%) URFs, ten (8.5%) subtype B, two (1.7%) subtype F1 and two (1.7%) CRF14_BG. Most recent common ancestor dating suggests that CRF01_AE was likely first introduced from Southeast Asia into persons reporting heterosexual infection in Bulgaria in 1992 and spread subsequently to PWIDs in the capital city of Sofia around 2003. Conversely, CRF02_AG in Bulgaria was likely first introduced into PWID from Germany in 2000 and later entered heterosexual populations around 2009. The overall prevalence of resistance mutations was 6.8% (8/117), of which 5.1% (5/117) was observed in patients on antiretroviral therapy and 1.7% (2/117) was from transmitted drug resistance mutations in drug-naïve individuals. 189/204 (92.6%) PWIDs were also co-infected with hepatitis C (HCV) and 31/183 (16.9%) were co-infected with hepatitis B (HBV). Our study provides valuable molecular epidemiological information on the introduction and distribution of the main HIV-1 subtypes, resistance mutations and hepatitis co-infections among PWIDs with HIV-1 in Bulgaria which can be used to target prevention efforts.
authors.affiliation: National Reference Laboratory of HIV, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria. Electronic address: ivoalexiev@yahoo.com.
authors.forename: Ivailo
authors.initials: I
authors.lastname: Alexiev
authors.affiliation: Laboratory Branch, Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Anupama
authors.initials: A
authors.lastname: Shankar
authors.affiliation: National Reference Laboratory of HIV, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Reneta
authors.initials: R
authors.lastname: Dimitrova
authors.affiliation: National Reference Laboratory of HIV, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Anna
authors.initials: A
authors.lastname: Gancheva
authors.affiliation: National Reference Laboratory of HIV, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Asia
authors.initials: A
authors.lastname: Kostadinova
authors.affiliation: National Reference Laboratory of Hepatitis, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Pavel
authors.initials: P
authors.lastname: Teoharov
authors.affiliation: National Reference Laboratory of Hepatitis, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Elitsa
authors.initials: E
authors.lastname: Golkocheva
authors.affiliation: National Reference Laboratory of Immunology, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Maria
authors.initials: M
authors.lastname: Nikolova
authors.affiliation: National Reference Laboratory of Immunology, National Center of Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Mariya
authors.initials: M
authors.lastname: Muhtarova
authors.affiliation: Hospital for Infectious and Parasitic Diseases, Sofia, Bulgaria.
authors.forename: Ivaylo
authors.initials: I
authors.lastname: Elenkov
authors.affiliation: Department of Infectious Diseases, Medical University, Plovdiv, Bulgaria.
authors.forename: Mariyana
authors.initials: M
authors.lastname: Stoycheva
authors.affiliation: Clinic of Infectious Diseases, Medical University, Varna, Bulgaria.
authors.forename: Daniela
authors.initials: D
authors.lastname: Nikolova
authors.affiliation: Program Prevention and Control of HIV/AIDS, Ministry of Health, Sofia, Bulgaria.
authors.forename: Tonka
authors.initials: T
authors.lastname: Varleva
authors.affiliation: Laboratory Branch, Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: William M
authors.initials: WM
authors.lastname: Switzer
mesh_terms: D000293:Adolescent; D000328:Adult; D002031:Bulgaria / Q000453:epidemiology; D024882:Drug Resistance, Viral / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D015658:HIV Infections / Q000150:complications / Q000453:epidemiology / Q000635:transmission / Q000821:virology; D015497:HIV-1 / Q000145:classification / Q000235:genetics; D006509:Hepatitis B / Q000150:complications / Q000453:epidemiology; D006526:Hepatitis C / Q000150:complications / Q000453:epidemiology; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D010802:Phylogeny; D015995:Prevalence; D015819:Substance Abuse, Intravenous / Q000150:complications / Q000453:epidemiology; D055815:Young Adult
keywords: Drug resistance; HIV; Hepatitis; Injection drug use; Molecular epidemiology; Subtype