Seroepidemiology of human T-cell lymphotropic virus among Iranian adult thalassemic patients

Updates on the Epidemiology of the Human T-Cell Leukemia Virus Type 1 Infection in the Countries of the Eastern Mediterranean Regional Office of the World Health Organization with Special Emphasis on the Situation in Iran

Background: The epidemiology and prevalence of the Human T-cell leukemia virus type-1 (HTLV-1) infection represent a recommended priority by global health agencies. An in-depth revision to update the status of this infection in countries including those of the Eastern Mediterranean Regional Office (EMRO) of the World Health Organization is hence required. Methods: Ninety-seven studies evaluating the HTLV-1 infection in low- and high-risk populations in EMRO countries were retrieved from the international electronic databases and were used to assess the epidemiological status of the infection in these countries. Results: Most epidemiologic reports were published from Iran, with more than 50% of Iranian prisoners and around 4% of healthy individuals reported to have the infection. In Egypt, a considerable prevalence of the virus spans around 1.11% of blood donors. Foci of HTLV-1 infection are also present in some countries and require a careful epidemiological evaluation. In the other EMRO countries, a lower prevalence that does not exceed 1% was reported. Conclusion: The epidemiology and prevalence of HTLV-1 in the EMRO countries require a tight revision and update. Published studies reveal a scarce distribution of the virus in the African countries of EMRO, while a lower prevalence is denoted in the Asian countries of EMRO, except in Iran, where the prevalence is high.

Phylogenetic analysis of HTLV-1 in Iranian blood donors, HIV-1 positive patients and patients with beta thalassemia

Human T-cell lymphoma virus (HTLV) has been associated with various disease types. Since the discovery of the virus in 1980, seven subtypes of the virus have been identified. HTLV is widespread and endemic in some regions, such as Japan, Africa, South America, and northeast Iran. This study aimed to identify HTLV-1 genotype and also to analyze the nucleotide sequence of the LTR region in three groups, including blood donors, HIV-1+ patients, and β-thalassemia patients. In this cross-sectional study, 2200 samples were collected from blood donors in Tehran (2000 samples), HIV-1+ patients (100 samples) and β-thalassemia patients (100 samples). All samples were screened for anti-HTLV-I&II antibodies by ELISA. Then, genomic DNA was extracted from repeatedly positive samples, and nested PCR was performed for both the TAX and LTR regions. Purified PCR products were sequenced and analyzed, and finally, a phylogenetic tree was constructed using Mega7 software. The prevalence of the anti-HTLV-I&II antibody among blood donors and HIV-1+ patients was 1.7% (34/2000) and 12% (12/100), respectively. The PCR results confirmed that 0.05% (1/2000) of blood donors, 5% (5/100) of HIV-1+ patients, and 8% (8/100) of β-thalassemia patients were HTLV-I positive. All sequences were matched to HTLV-1 subtype a, subgroup A. Our phylogenetic analysis revealed that all sequenced samples belong to the endemic clusters of Iran. HTLV-1 genotypes in all samples were similar in three groups and were derived from the strains, which had been previously reported from Iran (AF00300/Mashhad and KT190712.1/Sabzevar).

The epidemiology of hepatitis C virus in Iran: Systematic review and meta-analyses

The aim of this study was to characterize hepatitis C virus (HCV) epidemiology in Iran and estimate the pooled mean HCV antibody prevalence in different risk populations. We systematically reviewed and synthesized reports of HCV incidence and/or prevalence, as informed by the Cochrane Collaboration Handbook, and reported our findings following the PRISMA guidelines. DerSimonian-Laird random effects meta-analyses were implemented to estimate HCV prevalence in various risk populations. We identified five HCV incidence and 472 HCV prevalence measures. Our meta-analyses estimated HCV prevalence at 0.3% among the general population, 6.2% among intermediate risk populations, 32.1% among high risk populations, and 4.6% among special clinical populations. Our meta-analyses for subpopulations estimated HCV prevalence at 52.2% among people who inject drugs (PWID), 20.0% among populations at high risk of healthcare-related exposures, and 7.5% among populations with liver-related conditions. Genotype 1 was the most frequent circulating strain at 58.2%, followed by genotype 3 at 39.0%. HCV prevalence in the general population was lower than that found in other Middle East and North Africa countries and globally. However, HCV prevalence was high in PWID and populations at high risk of healthcare-related exposures. Ongoing transmission appears to be driven by drug injection and specific healthcare procedures.

Prevalence and phylogenic study of human T-lymphotropic virus 1 in patients with thalassemia in the northeast of Iran

Aim: This study aimed to investigate the frequency and phylogenetic distribution of human T-lymphotropic virus type 1 (HTLV-1) in thalassemia cases. Methods: Between 2006 and 2013, a total of 100 thalassemic individuals were investigated for HTLV-1 infections. Results: Four people (4%) were reactive for HTLV antibodies. No considerable correlation was seen between factors such as age, blood transfusion history, surgery, marital status, gender and blood types. All HTLV-1 sequences belonged to the transcontinental (A) subgroup in the cosmopolitan (a) subtype. Conclusion: In addition to phylogenetic distribution, our results demonstrate that the prevalence of HTLV-1 infection among thalassemia patients in Mashhad is higher than that of previous studies.