AIMS: The aim of the present study is the preliminary characterization of an El Tor vibriophage M4 (ATCC 51352-B4). METHODS: We studied the growth characteristics and sustainability of this phage under various stresses l...AIMS: The aim of the present study is the preliminary characterization of an El Tor vibriophage M4 (ATCC 51352-B4). METHODS: We studied the growth characteristics and sustainability of this phage under various stresses like temperature, pH, and UV. The phage morphology and phage genome were also examined using electron microscopy. RESULTS: Sustainability studies showed that the phage is more stable in acidic conditions, which is very uncommon among vibriophages. Studies also showed that M4 is a thermostable phage and it is inactivated by temperatures above 60°C but, like other phages, UV has a high inactivating effect on it. Morphological and genomic studies by electron microscopy showed that this phage has a long contractile tail and a big head. The genome is linear and about 120 kb in length. The genome also has a high packaging density as the value of Vm (the volume occupied per Da of biological macromolecule) is low for this phage. The phage-bacterial interaction was studied by negative staining as well as ultrathin sectioning methods. CONCLUSIONS: M4 belongs to the Myoviridae family and it is generally thermostable. It is prone to destruction by alkali and UV. It also has a large DNA which is densely packed inside of a big capsid.
OBJECTIVES: Resistance-associated mutations (RAMs) in the integrase of different HIV-1 subtypes were investigated in a cohort of patients never exposed to integrase strand transfer inhibitors (INSTIs). METHODS: The viral...OBJECTIVES: Resistance-associated mutations (RAMs) in the integrase of different HIV-1 subtypes were investigated in a cohort of patients never exposed to integrase strand transfer inhibitors (INSTIs). METHODS: The viral RNA was extracted from plasma samples of 53 INSTI-naïve patients, and the integrase genetic region was sequenced and analyzed for subtype assignment and drug resistance. RESULTS: The median viral load at sampling was 5.28 × 104 RNA copies/mL. Bayesian phylogenetic analysis showed 85% of the HIV-1 isolates were non-B subtypes, with a predominance of subtypes C (22.6%) and CRF01_AE (26.4%). A total of 52 and 110 mutations were found in the integrase region of HIV-1 B and non-B subtypes, respectively. Nonpolymorphic INSTI-RAMs were not detected in this study. However, the accessory mutation E157Q was found in 1 patient with CRF02_AG, and the polymorphic mutations L74M/I that may contribute to a reduced susceptibility to INSTIs in the presence of major mutations were observed in 6 (13.3%) patients with non-B subtypes and 1 (12.5%) patient with the B subtype. Polymorphic mutations at positions known to harbor primary and accessory RAMs were also detected in this study. CONCLUSION: Our results highlight the importance of monitoring the emergence of INSTI-RAMS before and after the initiation of INSTI-based therapy.
Finding the predominant circulating subtype of human immunodeficiency virus type 1 (HIV-1) and surveying co-infection with other infectious viruses are crucial to making preventive decisions. To this end, 50 Iranian HIV-...Finding the predominant circulating subtype of human immunodeficiency virus type 1 (HIV-1) and surveying co-infection with other infectious viruses are crucial to making preventive decisions. To this end, 50 Iranian HIV-positive patients made up of 37 men and 13 women were selected. Most of the HIV-positive patients (70%) were intravenous drug users (IDUs), and 48 and 32% of patients were co-infected with HCV and HBV, respectively. The rate of simultaneous infection with HIV, HCV, and HBV was found to be 6%. The p17 region of the gag and the c2-v5 region of the env genes were sequenced and then clustered by phylogenetic analyses. CRF35-AD was specified as the predominant circulating subtype among different high-risk groups. In our survey, most of the patients in the IDU group had co-infections with HCV and HBV. Some possible reasons for the increased transmission risk of HIV in IDUs could be low levels of education, poor hygiene and housing conditions, and limited access to health services.
AIMS: The objective of this work was to study the distribution of hepatitis C virus (HCV) genotypes and subtypes from 2010 to 2015 in 1,221 anti-HCV/HCV-RNA-positive specimens from patients living in the metropolitan are...AIMS: The objective of this work was to study the distribution of hepatitis C virus (HCV) genotypes and subtypes from 2010 to 2015 in 1,221 anti-HCV/HCV-RNA-positive specimens from patients living in the metropolitan area of Naples, since HCV genotypes and subtypes remain cornerstones in the management of chronic HCV infection even in the directly acting antivirals era. METHODS: The study was carried out on 1,221 anti-HCV/HCV-RNA-positive plasma samples collected between April 2010 and December 2015. RESULTS: Of the 1,221 patients enrolled, 633 (51.9%) were males and 588 (48.1%) were females, with a mean age of 60 ± 13 (SD) years. The most frequent HCV genotype observed was genotype 1 (68.1%; 1b in 55.3% and 1a in 9.5%); HCV genotype 2 was found in 289 samples (23.67%), genotype 3 in 6.47%, genotype 4 in only 19 samples, and only 2 samples were classified as genotype 5. The mean age of the patients with genotype 1a or 3 was lower (51 ± 12 and 49 ± 12 years, respectively) than those with genotype 1b (62 ± 11, p < 0.0001 for both) or 2 (62 ± 14, p < 0.0001 for both). CONCLUSIONS: The data from the present study suggest that HCV genotype 1b remains the most prevalent in this area, followed by genotype 2, 1a, and 3a.
GII.4 noroviruses (NoVs) are a major cause of acute gastroenteritis in humans. A new variant of GII.4, the Sydney variant, has recently become more prevalent on a global scale. Intragenotype recombinations are widespread...GII.4 noroviruses (NoVs) are a major cause of acute gastroenteritis in humans. A new variant of GII.4, the Sydney variant, has recently become more prevalent on a global scale. Intragenotype recombinations are widespread within the pandemic NoV GII.4 lineage, and are likely to be important forces driving the evolution and emergence of novel GII.4 viruses. In this study, we sought to examine the role that intergenotype recombination has played in the emergence of GII.4 Sydney 2012 variants. The results show that the GII.4 Sydney 2012 variants, Kawasaki194 and CA3477, were intergenotype recombination NoV strains with a GII.4 capsid and a GII.P16 polymerase gene. It has been reported for the first time that GII.4 new variant recombinants come from intergenotype recombination of GII.P16 and GII.4 strains in the complete genome.
OBJECTIVES: This study investigated the etiology of acute viral hepatitis and compared the clinical features of hepatitis E virus (HEV) infections with those of other acute viral hepatitis infections in Korea. METHODS: T...OBJECTIVES: This study investigated the etiology of acute viral hepatitis and compared the clinical features of hepatitis E virus (HEV) infections with those of other acute viral hepatitis infections in Korea. METHODS: This study included 2,357 consecutive patients who were diagnosed with acute hepatitis, based on acute illness with jaundice or elevated alanine aminotransferase levels (>100 IU/L), between January 2007 and January 2016. Acute viral infections were observed in 23 (19.8%) patients with HEV, 49 (42.2%) patients with hepatitis A virus, 28 (24.1%) patients with hepatitis B virus, and 16 (13.8%) patients with hepatitis C virus. RESULTS: The incidence of acute HEV infection was higher among older patients (median age: 49 years) and male patients (69.6%), and was associated with the consumption of undercooked or uncooked meat (43.5%). Half of the acute HEV infections involved underlying liver disease, such as alcoholic liver disease, chronic hepatitis B, common bile duct stones, and autoimmune hepatitis. Two HEV-infected patients were diagnosed with Guillain-Barré syndrome, although no patients developed fulminant hepatitis. CONCLUSION: Our findings indicate that HEV infection in Korea is frequently transmitted through the consumption of raw meat and may cause acute or chronic liver disease.
OBJECTIVES: The present study aimed to examine the impact of rapid virological response (RVR) and early virological response (EVR) on sustained virological response (SVR) in chronic hepatitis C genotype 3a individuals. M...OBJECTIVES: The present study aimed to examine the impact of rapid virological response (RVR) and early virological response (EVR) on sustained virological response (SVR) in chronic hepatitis C genotype 3a individuals. METHODS: The patients were given antiviral therapy with IFN-α-2b, 3 million units 3 times a week and 800-1,200 mg of ribavirin daily adjusted to the patient's body weight (<60 kg 800 mg day-1, and >60 kg 1,200 day-1). The patients received this combination therapy for 24 weeks. The patients were evaluated for their viral load at week 4, 12, and 24 using RT-PCR. RESULTS: Out of 1,471 patients, 43.3% showed a negative viral load in week 4, demonstrating RVR, whereas 56.6% maintained a high viral load. These were further separated based on viral reduction in their plasma: either negative for HCV-RNA at week 12 (n = 575), manifesting EVR, or showing a 2-log reduction in HCV viral load classified as partial EVR (PEVR; n = 259). The PEVR response was less (29.7%) compared with RVR (85.9%) and EVR (69.0%), although nonresponders were found in both groups. CONCLUSIONS: Individuals incompliant with their treatment who have a higher RVR significantly influence their SVR towards a better remission that can be treated within a short duration with standard treatment.
OBJECTIVE: Torque teno virus (TTV) is a ubiquitous virus that is commonly associated with blood transfusion. The main aims of this study were to evaluate the incidence of TTV in polytransfused children with thalassemia a...OBJECTIVE: Torque teno virus (TTV) is a ubiquitous virus that is commonly associated with blood transfusion. The main aims of this study were to evaluate the incidence of TTV in polytransfused children with thalassemia and to determine for the first time the prevalent TTV genotypes in Egypt. METHODS: TTV was detected in 2 groups by nested PCR: the first group comprised 200 children with thalassemia, and the second included age- and sex-matched healthy children with no history of blood transfusion. RESULTS: TTV was detected in 60 and 57%, respectively, of the children with thalassemia and the healthy children. Among the TTV-positive children with thalassemia, 71.6% were HCV positive. No hepatitis B surface antigen was detected in the thalassemic children. Significant elevations of alanine transaminase and aspartate transaminase were found in TTV-positive patients with thalassemia compared to TTV-negative patients. Phylogenetic analysis of sequenced TTV isolates showed close relationships to genotypes 1 and 2. CONCLUSION: TTV is highly prevalent among children with thalassemia in Egypt, with a relatively high infection rate also detected among healthy children.
BACKGROUND: Although successful, the second-generation hepatitis B vaccine programs around the world have a small group of immunized individuals that does not respond efficiently to the vaccination. Other issues of these...BACKGROUND: Although successful, the second-generation hepatitis B vaccine programs around the world have a small group of immunized individuals that does not respond efficiently to the vaccination. Other issues of these vaccines are individuals that are low or nonresponders and/or have incomplete protection against heterologous hepatitis B virus (HBV) genotypes/subtypes and against HBV escape mutants. In addition, there are approximately 240 million people chronically infected with HBV worldwide and 620,000 deaths per year caused by the infection. METHODS: In this study we developed three Hansenula polymorpha plasmids containing the following sequences: (a) HBsAg subtype ayw, (b) HBcAg sequence subtype adw2, and (c) chimeric HBsAg (adw4/ ayw) - preS1 (adw2) - 3 repetitions of preS2 (genotypes A, B, and C). The sequences were successfully expressed and the antigens purified. Using Balb/c mice the antigens were tested in different dosage combinations. RESULTS: Three antigens were obtained at a high purity level and with high reproducibility. We also assessed their immunogenic properties, showing that the antigens, individually or in combination, generated anti-HBs, anti-preS1, anti-preS2, and anti-HBc antibodies efficiently in mice. CONCLUSIONS: The formulation tests showed that a combination of 0.02 μg of HBs, 0.2 μg of preS1-preS2-HBs, and 0.02 μg of HBc was effective in eliciting specific antibodies in mice.
Sarquiz-Martínez B, González-Bonilla CR, Santacruz-Tinoco CE
… +5 more, Muñoz-Medina JE, Pardavé-Alejandre HD, Barbosa-Cabrera E, Ramírez-González JE, Díaz-Quiñonez JA
BACKGROUND: Enterovirus (EV) and herpes simplex virus 1 and 2 (HSV1 and HSV2) are the main etiologic agents of central nervous system infections. Early laboratory confirmation of these infections is performed by viral cu...BACKGROUND: Enterovirus (EV) and herpes simplex virus 1 and 2 (HSV1 and HSV2) are the main etiologic agents of central nervous system infections. Early laboratory confirmation of these infections is performed by viral culture of the cerebrospinal fluid (CSF), or the detection of specific antibodies in serum (e.g., HSV). The sensitivity of viral culture ranges from 65 to 75%, with a recovery time varying from 3 to 10 days. Serological tests are faster and easy to carry out, but they exhibit cross-reactivity between HSV1 and HSV2. Although molecular techniques are more sensitive (sensitivity >95%), they are more expensive and highly susceptible to cross-contamination. METHODS: A real-time RT-PCR for the detection of EV, HSV1, and HSV2 was compared with end-point nested PCR. RESULTS: We tested 87 CSF samples of patients with a clinical diagnosis of viral meningitis or encephalitis. Fourteen samples were found to be positive by RT-PCR, but only 8 were positive by end-point PCR. The RT-PCR showed a specificity range of 94-100%, the negative predictive value was 100%, and the positive predictive value was 62, 100, and 28% for HSV1, HSV2, and EV, respectively. CONCLUSION: Real-time RT-PCR detected EV, HSV1, and HSV2 with a higher sensitivity and specificity than end-point nested RT-PCR.
Dengue and chikungunya fevers are transmitted by the common mosquito vector Aedes and malaria by Anopheles. Concurrent infections are reported due to co-circulation of these pathogens, especially in endemic regions. We r...Dengue and chikungunya fevers are transmitted by the common mosquito vector Aedes and malaria by Anopheles. Concurrent infections are reported due to co-circulation of these pathogens, especially in endemic regions. We report a rare case of triple infection with 3 arthropod-borne pathogens (Plasmodium vivax and the dengue and chikungunya viruses) in a 3-year-old child from New Delhi, India, in August 2016. The viruses were identified by RT-PCR and the parasite by microscopy and antigen detection. The dengue virus serotype 3 sequence was clustered in the genotype III by the phylogenetic analysis. Mixed infection with multiple pathogens is a challenge for accurate diagnosis due to the overlapping clinical symptoms. The accurate and timely diagnosis of multiple pathogens in such cases is important for rapid and effective patient management.
Trionyx sinensis hemorrhagic syndrome virus (TSHSV) is a pathogen that causes severe hemorrhagic syndrome and irreversible damage to different infected tissues of Pelodis cus sinensis, ending in the death of affected org...Trionyx sinensis hemorrhagic syndrome virus (TSHSV) is a pathogen that causes severe hemorrhagic syndrome and irreversible damage to different infected tissues of Pelodis cus sinensis, ending in the death of affected organisms. In the present study, the histopathological characteristics of TSHSV-infected P. sinensis were analyzed and compared by HE staining. Relative and absolute quantification (iTRAQ)-based proteomic analysis was employed to explore the molecular pathology of liver injury. Anatomical features indicated that TSHSV caused obvious congestion in the liver, kidney, intestine, and other tissues of P. sinensis. The typical clinical symptoms included hepatomegaly, fragility, spotty and severe congestion in liver tissue, and also obvious intestinal bleeding. The histopathological studies corroborated such lesions in the liver and kidney, etc. iTRAQ-based proteomic analysis revealed that there were 252 differentially expressed proteins in the liver tissue between healthy and infected P. sinensis, of which 118 proteins were upregulated and 134 proteins were downregulated. GO enrichment analysis and KEGG pathway analysis initially revealed the molecular mechanism of pathological changes in P. sinensis by TSHSV infection. The expression of some differentially expressed proteins was further confirmed by qRT-PCR. These results provided important information for the pathological diagnosis of TSHSV-caused disease, as well as the mechanism underlying TSHSV-caused disease.
OBJECTIVE: Syncytia formation is the hallmark of the cytopathic effect caused by human respiratory syncytial virus (HRSV), which is the most important viral respiratory pathogen in children. This article reports methodol...OBJECTIVE: Syncytia formation is the hallmark of the cytopathic effect caused by human respiratory syncytial virus (HRSV), which is the most important viral respiratory pathogen in children. This article reports methodological improvements in primary HRSV isolation and the importance of syncytia formation and mRNA levels of F protein for the progeny yield, using clinical isolates of HRSV. METHODS: The A and B strains of HRSV were isolated in HEp-2 cell cultures from fresh and frozen nasopharyngeal aspirates. The formation of syncytia was evaluated using 2 different assays. Levels of F protein mRNA were quantified by real-time PCR while HRSV progeny titration was done by plaque assay. RESULTS: HRSV was primarily isolated from 238 of 312 (90.7%) samples, and 13 of these (12 HRSV-A and 1 HRSV-B) were continuously passaged in vitro. The quantity and size of syncytia formed by 6 pure HRSV-A clinical isolates were different, as were the levels of F protein mRNA. CONCLUSION: There is a direct correlation of quantities of syncytia and inoculum size, but not with mRNA levels of HRSV-A F protein. Importantly, levels of F protein mRNA were directly related to progeny production.
Emerging Flaviviruses pose an increasing threat to global human health. To date, human vaccines against yellow fever virus (YFV), Japanese encephalitis virus (JEV), dengue virus (DV), and tick-borne encephalitis virus (T...Emerging Flaviviruses pose an increasing threat to global human health. To date, human vaccines against yellow fever virus (YFV), Japanese encephalitis virus (JEV), dengue virus (DV), and tick-borne encephalitis virus (TBEV) exist. However, there is no human vaccine against other Flaviviruses such as Zika virus (ZIKV) and West Nile virus (WNV). In order to restrict their spread and to protect populations against the diseases they induce, vaccines against these emerging viruses must be designed. Obtaining new live attenuated Flavivirus vaccines using molecular biology methods is now possible. Molecular infectious clones of the parental viruses are relatively easy to generate. Key mutations present in live attenuated vaccines or mutations known to have a key role in the Flavivirus life cycle and/or interactions with their hosts can be identified by sequencing, and are then inserted in infectious clones by site-directed mutagenesis. More recently, the use of chimeric viruses and large-scale reencoding and introduction of microRNA target sequences have also been tested. Indeed, a combination of these methods will help in designing new generations of vaccines against emerging and reemerging Flaviviruses.
Infection of human MRC-5 cells and mouse NIH-3T3 cells with a murine gamma-herpesvirus (MuHV-4 strain 68; MHV-68) photoinactivated by visible light in the presence of methylene blue (MB) resulted in nonproductive infecti...Infection of human MRC-5 cells and mouse NIH-3T3 cells with a murine gamma-herpesvirus (MuHV-4 strain 68; MHV-68) photoinactivated by visible light in the presence of methylene blue (MB) resulted in nonproductive infection and the appearance of morphologically transformed cells. Two stably transformed cell lines were derived from both of these cell types and were confirmed to contain both viral DNA and antigen. Next, a quiescent MHV-68 infection in MRC-5 and NIH-3T3 cells was established after cultivation at 41°C in the presence of phosphonoacetic acid. Following the exposure of quiescently infected cells to visible light for 120 s (5 times daily for 6 days) in the presence of MB, both MRC-5 and NIH-3T3 cells were observed to acquire transformed phenotypes. The cytopathic effect was observed in cells after 4-5 passages, after which the cells degenerated. However, when human interferon (IFN)-α and mouse IFN-β were added to the media of quiescently infected MRC-5 and NIH-3T3 cells during the photoinactivating procedure, 2 stable transformed cell lines containing both viral DNA and the antigen were obtained and resembled those attained following nonproductive infection with photoinactivated virus.
OBJECTIVE: The role of Merkel cell polyomavirus (MCPyV) as a respiratory pathogen is controversial. The aim of this study was to determine the prevalence of MCPyV in patients with acute respiratory diseases and chronic l...OBJECTIVE: The role of Merkel cell polyomavirus (MCPyV) as a respiratory pathogen is controversial. The aim of this study was to determine the prevalence of MCPyV in patients with acute respiratory diseases and chronic lung diseases, including lung cancer, in order to evaluate the association between MCPyV infection and respiratory diseases. METHODS: This study included 221 specimens (133 nasopharyngeal swabs and 88 lung biopsy specimens) obtained from patients with acute respiratory diseases and chronic lung diseases, including lung cancer. The detection of MCPyV was performed via nested polymerase chain reaction. RESULTS: MCPyV positivity was 4.3% on average. All nasopharyngeal specimens were obtained from patients with acute respiratory diseases, and 8.2% of them were MCPyV DNA positive. There were no statistically significant differences in MCPyV prevalence according to age or gender. All specimens from nonmalignant chronic lung diseases and lung cancer were MCPyV negative. CONCLUSIONS: MCPyV was observed in specimens from patients with acute respiratory diseases, indicating that there may be a relationship between the virus and these diseases. We were not able to detect MCPyV in samples from patients with chronic lung diseases, including lung cancer, suggesting no association with MCPyV infection and no involvement of this polyomavirus in lung cancerogenesis.
The 2009 H1N1 influenza pandemic, which involved a more pathogenic virus than seasonal influenza viruses, rapidly spread around the world and caused many deaths in humans. The members of the interferon-induced transmembr...The 2009 H1N1 influenza pandemic, which involved a more pathogenic virus than seasonal influenza viruses, rapidly spread around the world and caused many deaths in humans. The members of the interferon-induced transmembrane (IFITM) protein family prevent viral replication and are crucial for defending the host cell against influenza A virus (IAV). Several studies suggest that the CC genotype at the single nucleotide polymorphism (SNP) rs12252 of IFITM3 confers a genetic predisposition to pandemic influenza A in Europeans and Han Chinese, although one study in a British cohort failed to show an association. In order to examine whether an SNP of the IFITM3 gene is correlated with the disease severity of pandemic IAV (H1N1) infection in a Korean population, we investigated the genotype and allele frequencies of this polymorphism in 300 healthy Koreans by automatic direct sequencing and compared the disease severity based on epidemiological studies of the H1N1 virus reported in several countries. The frequencies of the CC genotype and the C allele in the IFITM3 polymorphism were higher in the Korean population than in the European populations, but not in Chinese and Japanese populations. The prevalence of severe cases of the pandemic 2009 IAV infection in Koreans was similar to that in Europeans (p = 0.106). In addition, the prevalence of deaths among all positive cases with pandemic 2009 IAV infection in Koreans was significantly lower than that in Europeans. These results suggest that the IFITM3 genotype may not be a determinant of disease severity of IAV infection.
BACKGROUND: Insufficient therapy during HIV-1 replication can promote the emergence of drug-resistant strains, reduce the effectiveness of antiretroviral treatment (ART), and increase the likelihood of the onward transmi...BACKGROUND: Insufficient therapy during HIV-1 replication can promote the emergence of drug-resistant strains, reduce the effectiveness of antiretroviral treatment (ART), and increase the likelihood of the onward transmission of drug-resistant viruses. We characterized, for the first time, the prevalence of HIV-1 subtypes and drug resistance mutations in a western region of Iran. METHODS: This study was conducted among 122 patients on ART at a major referral center in Kermanshah, Iran. Nested PCR was performed using RT gene-specific primers from the pol gene. Sequencing was followed by amplification and purification of the desired sequence. Subtypes and mutations were determined using the Stanford HIV Drug Resistance Database. RESULTS: Most patients (92.6%) had subtype CRF 35-AD; 7.4% had subtype B. In total, 36.1% of the patients had at least 1 mutation associated with resistance RT inhibitors. The greatest rates of high-level resistance were observed for nevirapine (21.3%) and efavirenz (19.7%). CONCLUSIONS: Our results showed a high prevalence of drug resistance mutations in strains isolated from patients on treatment. At our center, we therefore recommend that genotyping be performed. This would allow the physician to prescribe appropriate drugs, reduce treatment costs, and increase the longevity and quality of life of patients.
Incidences of emerging/re-emerging deadly viral infections have significantly affected human health despite extraordinary progress in the area of biomedical knowledge. The best examples are the recurring outbreaks of den...Incidences of emerging/re-emerging deadly viral infections have significantly affected human health despite extraordinary progress in the area of biomedical knowledge. The best examples are the recurring outbreaks of dengue and chikungunya fever in tropical and sub-tropical regions, the recent epidemic of Zika in the Americas and the Caribbean, and the SARS, MERS, and influenza A outbreaks across the globe. The established natural reservoirs of human viruses are mainly farm animals, and, to a lesser extent, wild animals and arthropods. The intricate "host-pathogen-environment" relationship remains the key to understanding the emergence/re-emergence of pathogenic viruses. High population density, rampant constructions, poor sanitation, changing climate, and the introduction of anthropophilic vectors create selective pressure on host-pathogen reservoirs. Nevertheless, the knowledge and understanding of such zoonoses and pathogen diversity in their known non-human reservoirs are very limited. Prevention of arboviral infections using vector control methods has not been very successful. Currently, new approaches to protect against food-borne infections, such as consuming only properly cooked meats and animal products, are the most effective control measures. Though significant progress in controlling human immunodeficiency virus and hepatitis viruses has been achieved, the unpredictable nature of evolving viruses and the rare occasions of outbreaks severely hamper control and preventive modalities.
Abacavir is an effective antiretroviral drug and one of the most commonly used nucleoside reverse transcriptase inhibitors in Serbia. А percentage of the treated patients experience a potentially life-threatening hyperse...Abacavir is an effective antiretroviral drug and one of the most commonly used nucleoside reverse transcriptase inhibitors in Serbia. А percentage of the treated patients experience a potentially life-threatening hypersensitivity reaction, which was shown to be associated with the presence of the class I MHC allele, HLA-B*57:01; hence genotyping for HLA-B*57:01 prior to starting abacavir is nowadays recommended in international HIV treatment guidelines. In Serbia, this testing became available in 2013. This study was designed to estimate the prevalence of the HLA-B*57:01 allele in Serbian HIV-1-infected patients. The presence of the HLA-B*57:01 allele was analyzed in 273 HIV-1-infected patients aged 18 years or more, who were abacavir naïve. Buccal swab samples were obtained from all participants and assayed for the presence of HLA-B*57:01 using a commercially available HLA-B*57:01 real-time PCR kit. The presence of the HLA-B*57:01 allele was found in 22 of 273 tested individuals (8%; 95% CI 5.4-11.9%). This is the first study that estimated the HLA-B*57:01 prevalence among HIV-infected patients in Serbia. The very high prevalence of HLA-B*57:01 found in our study strongly supports HLA-B*57:01 genotyping, which should be implemented prior to the initiation of an abacavir-containing therapy to reduce the risk of potentially life-threatening hypersensitivity reactions.