Summary. -Parvovirus B19 (B19V) is a small non-enveloped single-stranded DNA (ssDNA) virus of the family Parvoviridae, the subfamily Parvovirinae, the genus Erythrovirus and Human parvovirus B19 type species. It is a common community-acquired respiratory pathogen without ethnic, socioeconomic, gender, age or geographic boundaries. Moreover, the epidemiological and ecological relationships between human parvovirus B19, man and environment have aroused increasing interest in this virus. B19V infection is associated with a wide spectrum of clinical manifestations, some of which were well established and some are still controversial, however, it is also underestimated from a clinical perspective. B19V targets the erythroid progenitors in the bone marrow by binding to the glycosphingolipid globoside (Gb4), leading to large receptor-induced structural changes triggering cell death either by lysis or by apoptosis mediated by the nonstructural (NS)1 protein. The pattern of genetic evolution, its peculiar properties and functional profile, the characteristics of its narrow tropism and restricted replication, its complex relationship with the host and its ample pathogenetic potential are all topics that are far from a comprehensive understanding. The lack of efficient adaptation to in vitro cellular cultures and the absence of animal models have limited classical virological studies and made studies on B19V dependent on molecular biology. The present review looks at the nature of this virus with the view to provide more information about its biology, which may be useful to the present and future researchers.Keywords: human parvovirus B19; respiratory pathogen; biology; genome; fifth disease; transient aplastic crisis; anemia * Corresponding author. E-mail: rezaie@tums.ac.ir; phone: +982188982343. Abbreviations: B19V = parvovirus B19; Gb4 = glycosphingolipid globoside; IL-6 = interleukin 6; IVIG = intravenous immunoglobulin G; MHC = major histocompatibility class; SF3-helicase = superfamily 3 helicase; NS = nonstructural; TNF-α = tumor necrosis factor α; VLPs = virus like particles; VP1 = viral protein 1; VP2 = viral protein 2

Based on available metabolomic studies, influenza infection affects a variety of cellular metabolic pathways to ensure an optimal environment for its replication and production of viral particles. Following infection, glucose uptake and aerobic glycolysis increase in infected cells continually, which results in higher glucose consumption. The pentose phosphate shunt, as another glucose-consuming pathway, is enhanced by influenza infection to help produce more nucleotides, especially ATP. Regarding lipid species, following infection, levels of triglycerides, phospholipids, and several lipid derivatives undergo perturbations, some of which are associated with inflammatory responses. Also, mitochondrial fatty acid βoxidation decreases significantly simultaneously with an increase in biosynthesis of fatty acids and membrane lipids. Moreover, essential amino acids are demonstrated to decline in infected tissues due to the production of large amounts of viral and cellular proteins. Immune responses against influenza infection, on the other hand, could significantly affect metabolic pathways. Mainly, interferon (IFN) production following viral infection affects cell function via alteration in amino acid synthesis, membrane composition, and lipid metabolism. Understanding metabolic alterations required for influenza virus replication has revealed novel therapeutic methods based on targeted inhibition of these cellular metabolic pathways.

Summary The alarming rise of morbidity and mortality caused by influenza pandemics and epidemics has drawn attention worldwide since the last few decades. This life‐threatening problem necessitates the development of a safe and effective vaccine to protect against incoming pandemics. The currently available flu vaccines rely on inactivated viral particles, M2e‐based vaccine, live attenuated influenza vaccine (LAIV) and virus like particle (VLP). While inactivated vaccines can only induce systemic humoral responses, LAIV and VLP vaccines stimulate both humoral and cellular immune responses. Yet, these vaccines have limited protection against newly emerging viral strains. These strains, however, can be targeted by universal vaccines consisting of conserved viral proteins such as M2e and capable of inducing cross‐reactive immune response. The lack of viral genome in VLP and M2e‐based vaccines addresses safety concern associated with existing attenuated vaccines. With the emergence of new recombinant viral strains each year, additional effort towards developing improved universal vaccine is warranted. Besides various types of vaccines, microRNA and exosome‐based vaccines have been emerged as new types of influenza vaccines which are associated with new and effective properties. Hence, development of a new generation of vaccines could contribute to better treatment of influenza.

No abstract

Background The increased levels of blood cytokines is the main immunopathological process that were attributed to severe clinical outcomes in cases of influenza A, influenza B and people with influenza-like illness (ILI). Functional genetic polymorphisms caused by single nucleotide polymorphisms (SNPs) in inflammatory cytokines genes can influence their functions either qualitatively or quantitatively, which is associated with the possibility of severe influenza infections. The aim of the present case-control study was to investigate the association of polymorphisms in inflammatory cytokines genes with influenza patients and ILI group in an Iranian population. Methods Total number of 30 influenza B, 50 influenza A (H1N1) and 96 ILI inpatient individuals were confirmed by Real-time RT-PCR and HI assays. The genotype determination was assessed for defined SNPs in IL-1β, IL-17, IL-10 and IL-28 genes. Results The frequencies of the IL-1β rs16944 ( P = 0.007 ) and IL-17 rs2275913 ( P = 0.006 ) genotypes were associated with severe influenza disease, while the frequencies of IL-10 rs1800872 and IL-28 rs8099917 were not associated with the disease ( P > 0.05 ). Also, the absence of A allele in IL-17 rs2275913 SNP increased the risk of influenza A (H1N1) infection ( P = 0.008 ). Conclusions This study demonstrated that influenza A- (H1N1) and B-infected patients and also ILI controls have different profiles of immune parameters, and individuals carrying the specific cytokine-derived polymorphisms may show different immune responses towards severe outcome.

The Framingham 10-year cardiovascular disease risk is measured by laboratory-based and non-laboratory-based models. This study aimed to determine the agreement between these two models in a large population in Southern Iran. In this study, the baseline data of 8138 individuals participated in the Pars cohort study were used. The participants had no history of cardiovascular disease or stroke. For the laboratory-based risk model, scores were determined based on age, sex, current smoking, diabetes, systolic blood pressure (SBP) and treatment status, total cholesterol, and High-Density Lipoprotein. For the non-laboratory-based risk model, scores were determined based on age, sex, current smoking, diabetes, SBP and treatment status, and Body Mass Index. The agreement between these two models was determined by Bland Altman plots for agreement between the scores and kappa statistic for agreement across the risk groups. Bland Altman plots showed that the limits of agreement were reasonable for females < 60 years old (95% CI: −2.27–4.61%), but of concern for those ≥ 60 years old (95% CI: −3.45–9.67%), males < 60 years old (95% CI: −2.05–8.91%), and males ≥ 60 years old (95% CI: −3.01–15.23%). The limits of agreement were wider for males ≥ 60 years old in comparison to other age groups. According to the risk groups, the agreement was better in females than in males, which was moderate for females < 60 years old (kappa = 0.57) and those ≥ 60 years old (kappa = 0.51). The agreement was fair for the males < 60 years old (kappa = 0.39) and slight for those ≥ 60 years old (Kappa = 0.14). The results showed that in overall participants, the agreement between the two risk scores was moderate according to risk grouping. Therefore, our results suggest that the non-laboratory-based risk model can be used in resource-limited settings where individuals cannot afford laboratory tests and extensive laboratories are not available.

Background:This paper presents the methodology and early findings of the fifth survey of a school-based surveillance program in Iran.Methods:This nationwide study was conducted in 2015 as the fifth survey of a surveillance program entitled “Childhood and Adolescence Surveillance and PreventIon of Adult Non- communicable disease” (CASPIAN-V) study. The protocol was mainly based on the World Health Organization-Global School student Health Survey. We studied 14400 students, aged 7-18 years, and their parents living in 30 provinces in Iran. Fasting blood was obtained from a sub-sample of 4200 randomly selected students.Results:The participation rate for the whole study and for blood sampling were 99% and 91.5%, respectively. The mean (SD) age of participants was 12.3 (3.2) years, consisting of 49.4% girls and 71.4% urban residents. Overall, 16.1% were underweight (17.4% of boys and 14.8% of girls), and 20.8% had excess weight consisting of 9.4% (8.7% of boys and 10.2% of girls) of overweight and 11.4% (12.5% of boys and 10.3% of girls) of obesity. Abdominal obesity was documented in 21.1% of students (21.6% of boys and 20.5% of girls). Low HDL-C was the most prevalent abnormality of the lipid profile (29.5%) followed by high serum triglycerides (27.7%). Of students, 59.9% consumed whole wheat bread; and 57% reported that they never or rarely added salt to table. The reported daily consumption of fresh fruits, vegetables, and milk was about 60%, 32% and 40%, respectively. 13.7% of participants had at least 30-min daily leisure-time physical activity.Conclusions:The current findings provide an overview of the current health status and lifestyle habits of children and adolescents. This surveillance program would help planning preventive programs at individual and community levels.

Metabolic syndrome (MetS) and its contributing factors are considered important health problems in the pediatric age group. This study was designed to assess the joint association of ST and PA with cardiometabolic risk factors among Iranian adolescents. A representative sample of 5625 (50.2% boys) school students with a mean age of 14.73 (SD: 2.41) were selected through multistage random cluster sampling method from urban and rural areas of 27 provinces in Iran. ST and PA were assessed by self-administered validated questionnaires. Anthropometric measures (height, weight and waist circumference (WC)) and MetS components (abdominal obesity, elevated blood pressure (BP), low high-density lipoprotein cholesterol (HDL-C), elevated triglycerides (TG) and high fasting blood sugar (FBG)) were measured according to standardized protocols. MetS was defined according to the Adult Treatment Panel III criteria modified for the pediatric age group. Moreover, elevated total cholesterol (TC), elevated low-density lipoprotein cholesterol (LDL-C), and generalized obesity were considered as other cardiometabolic risk factors. Students with high ST levels had significantly higher body mass index z-score (BMI z-score), WC, TG, LDL-C, and BP as well as lower HDL-C level; whereas those with high PA levels had significantly higher HDL-C levels as well as lower BMI z-score, TC, and BP. Adolescents with low PA/ high ST levels had significantly higher BMI, WC, LDL-C levels, as well as higher SBP and DBP compared to their other counterparts. In Multivariate model, joint effect of low PA/ high ST (compared to the high PA/low ST group) increased the odds of overweight, abdominal obesity and low HDL-C and decreased the odds of elevated TC. The findings of this study showed that joint association of high ST and low PA have direct association with abdominal obesity, overweight and low HDL-C and indirect association with elevated TC.