Little is known about the HIV-1 epidemic in Balkan countries.

HIV-1 strain diversity in Bulgaria is extensive and includes contributions from nearly all major subtypes and the Circulating Recombinant Forms (CRF): 01_AE, 02_AG, and 05_DF. Prior to this study, HIV-1 sequence information from Bulgaria has been based solely on the pro-RT gene, which represent less than 15% of the viral genome. To further characterize HIV-1 in Bulgaria, assess participant risk behaviors, and strengthen knowledge of circulating strains in the region, the study “Genetic Subtypes of HIV-1 in Bulgaria (RV240)” was conducted. This study employed the real time-PCR based Multi-region Hybridization Assay (MHA) B/non-B and HIV-1 sequencing to survey 215 of the approximately 1100 known HIV-1 infected Bulgarian adults (2008–2009) and determine if they were infected with subtype B HIV-1. The results indicated a subtype B prevalence of 40% and demonstrate the application of the MHA B/non-B in an area containing broad HIV-1 strain diversity. Within the assessed risk behaviors, the proportion of subtype B infection was greatest in men who have sex with men and lowest among those with drug use risk factors. During this study, 15 near full-length genomes and 22 envelope sequences were isolated from study participants. Phylogenetic analysis shows the presence of subtypes A1, B, C, F1, and G, CRF01_AE, CRF02_AG, CRF05_DF, and one unique recombinant form (URF). These sequences also show the presence of two strain groups containing participants with similar risk factors. Previous studies in African and Asian cohorts have shown that co-circulation of multiple subtypes can lead to viral recombination within super-infected individuals and the emergence of new URFs. The low prevalence of URFs in the presence of high subtype diversity in this study, may be the result of successful infection prevention and control programs. Continued epidemiological monitoring and support of infection prevention programs will help maintain control of the HIV-1 epidemic in Bulgaria.

Summary. Diarrhea is the most common gastrointestinal symptom in HIV-infected patients. The incidence and severity of diarrhea increase with progression of the immune defi ciency. In the literature, 30-60% of the patients with diarrhea among HIV-infected individuals remain without specifi ed etiological agent. The aim of this article is to present the incidence of enterocolitis among hospitalized HIV-infected patients over a 3-year period and the degree of etiological clarifi cation of the cause. The results of our analyses showed that 63% of the hospitalized HIV-infected patients for this period were with enterocolitis. Only in 30% of these patients etiological agent was isolated. The reasons for this are mainly fi nancial constraints and, therefore, virological investigations and further endoscopic and histopathological examination of the patients with negative for bacteria and parasites stool samples, were not performed. In the cases with isolated pathogen, an etiological treatment was carried out in parallel with highly active antiretroviral therapy, while in unsubstantiated cases an empirical treatment was carried out. Advanced immune defi ciency was associated with more severe course and worse prognosis of the enterocolitis. The treatment with highly active antiretroviral therapy, which leads to improvement of the immune status of the patients, is essential for the output of enterocolitis in HIV-infected patients.