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Showing papers in "Journal of Medical Virology in 2013"


Journal ArticleDOI
TL;DR: In this article, a prospective study was conducted to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain, where CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex), varicella-zoster [VZV], cytomegalovirus [CMV], Epstein-Barr [EBV], and human herpes virus-6 [HHV-6]), mV), Toscana virus (TOSV), adenovirus
Abstract: The aim of the study was to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain. This was a prospective study, in collaboration with 17 Spanish hospitals, including 581 cases (CSF from all and sera from 280): meningitis (340), meningoencephalitis (91), encephalitis (76), febrile syndrome (7), other neurological disorders (32), and 35 cases without clinical information. CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex [HSV], varicella-zoster [VZV], cytomegalovirus [CMV], Epstein-Barr [EBV], and human herpes virus-6 [HHV-6]), mumps (MV), Toscana virus (TOSV), adenovirus (HAdV), lymphocytic choriomeningitis virus (LCMV), West Nile virus (WNV), and rabies. Serology was undertaken when methodology was available. Amongst meningitis cases, 57.1% were characterized; EV was the most frequent (76.8%), followed by VZV (10.3%) and HSV (3.1%; HSV-1: 1.6%; HSV-2: 1.0%, HSV non-typed: 0.5%). Cases due to CMV, EBV, HHV-6, MV, TOSV, HAdV, and LCMV were also detected. For meningoencephalitis, 40.7% of cases were diagnosed, HSV-1 (43.2%) and VZV (27.0%) being the most frequent agents, while cases associated with HSV-2, EV, CMV, MV, and LCMV were also detected. For encephalitis, 27.6% of cases were caused by HSV-1 (71.4%), VZV (19.1%), or EV (9.5%). Other positive neurological syndromes included cerebellitis (EV and HAdV), seizures (HSV), demyelinating disease (HSV-1 and HHV-6), myelopathy (VZV), and polyradiculoneuritis (HSV). No rabies or WNV cases were identified. EVs are the most frequent cause of meningitis, as is HSV for meningoencephalitis and encephalitis. A significant number of cases (42.9% meningitis, 59.3% meningoencephalitis, 72.4% encephalitis) still have no etiological diagnosis.

147 citations


Journal ArticleDOI
TL;DR: The surprisingly high mortality in the D+R+‐transplant patients with CMV viraemia highlights the need for proactive monitoring of this group and demonstrates that CMV disease remains an important problem after organ transplantation.
Abstract: Cytomegalovirus infection (CMV) in solid organ transplant recipients is a major clinical problem. The aim of this study was to evaluate the incidence of CMV infection and its association with mortality during the first year after transplantation in a large solid organ transplant cohort at the Royal Infirmary of Edinburgh between January 2006 and April 2009. Data including the use of CMV prophylaxis, nature of CMV disease, treatment and deceased date (when appropriate) was collected retrospectively using hospital databases and patient notes for all transplanted patients with detectable CMV viraemia. The outcomes between recipients of kidney and liver transplants in the four CMV donor/recipient serostatus categories (D+R+, D-R-, D+R-, D-R+) were compared. A total of 428 individuals were included. Despite the administration of valganciclovir prophylaxis, CMV disease (syndrome or end-organ involvement) was diagnosed within the year of transplantation in the D+R--group in 31.3% of liver and 19.2% of kidney recipients. All D+R- transplant recipients that received CMV-prophylaxis presented with late-onset CMV disease. Furthermore, the rate of CMV disease in the D+R+-group was markedly higher in renal graft recipients compared to liver recipients (22% vs. 5%). The highest mortality was observed among the D+R+ liver and kidney graft recipients with CMV infection. The high incidence of late-onset CMV disease in D+R- transplant recipients receiving CMV prophylaxis demonstrates that CMV disease remains an important problem after organ transplantation. Furthermore, the surprisingly high mortality in the D+R+-transplant patients with CMV viraemia highlights the need for proactive monitoring of this group.

96 citations


Journal ArticleDOI
TL;DR: It is demonstrated that individuals with symptomatic respiratory viral infections produce both large and small particles carrying viral RNA on coughing and breathing.
Abstract: Aerosol transmission routes of respiratory viruses have been classified by the WHO on the basis of equilibrium particle size. Droplet transmission is associated with particles sized >5 µm in diameter and airborne transmission is associated with particles sized ≤5 µm in diameter. Current infection control measures for respiratory viruses are directed at preventing droplet transmission, although epidemiological evidence suggests concurrent airborne transmission also occurs. Understanding the size of particles carrying viruses can be used to inform infection control procedures and therefore reduce virus transmission. This study determined the size of particles carrying respiratory viral RNA produced on coughing and breathing by 12 adults and 41 children with symptomatic respiratory infections. A modified six-stage Andersen Sampler collected expelled particles. Each stage was washed to recover samples for viral RNA extraction. Influenza A and B, parainfluenza 1, 2 and 3, respiratory syncytial virus (RSV), human metapneumovirus and human rhinoviruses (hRV) were detected using RT-PCR. On breathing, 58% of participants produced large particles (>5 µm) containing viral RNA and 80% produced small particles (≤5 µm) carrying viral RNA. On coughing, 57% of participants produced large particles containing viral RNA and 82% produced small particles containing viral RNA. Forty five percent of participants produced samples positive for hRV viral RNA and 26% of participants produced samples positive for viral RNA from parainfluenza viruses. This study demonstrates that individuals with symptomatic respiratory viral infections produce both large and small particles carrying viral RNA on coughing and breathing. J. Med. Virol. 85:2151–2159, 2013. © 2013 Wiley Periodicals, Inc.

90 citations


Journal ArticleDOI
TL;DR: This review updates compilation of the available information for the HEV infection, both among humans and other mammals, in Latin America, discusses the strengths and the weaknesses of the current knowledge, and identifies future areas of research.
Abstract: Data reported during recent years reveal the complex picture of the epidemiology of hepatitis E virus (HEV) infection in Latin America. Whereas in countries like Argentina and Brazil is almost identical to the characteristic of most countries from North America and Europe, HEV in the Caribbean and Mexico involves the water-borne, non-zoonotic viral genotypes responsible for epidemics in Asia and Africa. Nevertheless, Latin America has been considered a highly endemic region for hepatitis E in the scientific literature, a generalization that ignores the above complexity. In addition, reports from isolated Amerindian communities, which display well known, important and very specific epidemiological features for hepatitis B and D virus infections are neither taken into account when considering the epidemiology of hepatitis E in the region. This review updates compilation of the available information for the HEV infection, both among humans and other mammals, in Latin America, discusses the strengths and the weaknesses of our current knowledge, and identifies future areas of research.

82 citations


Journal ArticleDOI
TL;DR: The CT values from the qRT‐PCR of upper respiratory tract specimens were associated with clinical severity for some respiratory viruses in all severity groups, and differences remained significant in logistic regression when controlling for age, days since onset, and coinfection.
Abstract: Quantitative real-time polymerase chain reaction (qRT-PCR) assay of the upper respiratory tract is used increasingly to diagnose lower respiratory tract infections. The cycle threshold (CT ) values of qRT-PCR are continuous, semi-quantitative measurements of viral load, although interpretation of diagnostic qRT-PCR results are often categorized as positive, indeterminate, or negative, obscuring potentially useful clinical interpretation of CT values. From 2008 to 2010, naso/oropharyngeal swabs were collected from outpatients with influenza-like illness, inpatients with severe respiratory illness, and asymptomatic controls in rural Kenya. CT values of positive specimens (i.e., CT values < 40.0) were compared by clinical severity category for five viruses using Mann-Whitney U-test and logistic regression. Among children <5 years old we tested with respiratory syncytial virus (RSV), inpatients had lower median CT values (27.2) than controls (35.8, P = 0.008) and outpatients (34.7, P < 0.001). Among children and older patients infected with influenza virus, outpatients had the lowest median CT values (29.8 and 24.1, respectively) compared with controls (P = 0.193 for children, P < 0.001 for older participants) and inpatients (P = 0.009 for children, P < 0.001 for older participants). All differences remained significant in logistic regression when controlling for age, days since onset, and coinfection. CT values were similar for adenovirus, human metapneumovirus, and parainfluenza virus in all severity groups. In conclusion, the CT values from the qRT-PCR of upper respiratory tract specimens were associated with clinical severity for some respiratory viruses.

73 citations


Journal ArticleDOI
TL;DR: It is indicated that viral or virus and bacterial co‐infections do not impact significantly on the clinical severity of acute exacerbation of chronic obstructive pulmonary disease and recurrence at 3 and 6 months.
Abstract: Few studies have evaluated the contribution of multiple virus and bacterial infections in acute exacerbation of chronic obstructive pulmonary disease. This study estimated the burden of multiple viral and bacterial respiratory infections in moderate to very severe chronic obstructive pulmonary disease patients that were prospectively followed-up during a 12-month pilot study. Clinical data were collected monthly and sputum was collected at the time of each acute exacerbation event. Classical culture techniques for bacteria and multiplex polymerase chain reaction (PCR) and microarray detection assays were performed to identify viral and atypical bacterial pathogens in the sputum. Overall, 51 patients were included and 45 acute exacerbation events were investigated clinically and microbiologically. Among the 45 acute exacerbation events, 44% had evidence of viral infection involving human rhinovirus (HRV) and metapneumovirus (hMPV) in 20% and 18%, respectively. Intracellular bacteria were not found in sputum by PCR. Common bacterial pathogens were identified in 42% of acute exacerbation patients, most frequently Branhamella catarrhalis, Streptococcus pneumoniae and Haemophilus influenzae. Viral or virus and bacteria co-infections were detected in 27% of acute exacerbation events (n = 12) with HRV and hMPV involved in 92% of cases. Patients with co-infections did not present greater clinical severity scores at exacerbation and more recurrence of acute exacerbation events at 3 and 6 months than those with single infections (P > 0.4). These results suggest that HRV and hMPV may be contributors or cofactors of AECOPD. These findings indicate that viral or virus and bacterial co-infections do not impact significantly on the clinical severity of acute exacerbation of chronic obstructive pulmonary disease and recurrence at 3 and 6 months. J. Med. Virol. 85:866–873, 2013. © 2013 Wiley Periodicals, Inc.

67 citations


Journal ArticleDOI
TL;DR: Results indicate that AdHu26 and AdC68 serve as more suitable vaccine vectors than AdHu5, and the most frequently detected and highest titer antibodies were specific for Ad Hu5.
Abstract: Replication-defective adenoviruses have been utilized as candidate vaccine vectors. However, clinical application of the best-studied human adenovirus type-5 (AdHu5) is limited by the high prevalence of preexisting neutralizing antibodies resulting from natural infection. Therefore, rare adenovirus serotypes, such as human adenovirus type-26 (AdHu26) and chimpanzee adenovirus type-68 (AdC68), have been employed as substitutes for AdHu5. However, few studies have described the epidemiology of pre-existing immunity to these adenoviruses in China. Thus, 1,154 participants from six regions in China were examined to assess the presence of neutralizing antibodies against AdHu5, AdHu26, and AdC68. The seroprevalence rates of neutralizing antibodies were as follows: AdHu5, 73.1% (844/1,154) (95% confidence interval: 70.5-75.6%); AdHu26, 35.3% (407/1,154) (95% confidence interval: 32.6-38.1%); and AdC68, 12.7% (147/1,154) (95% confidence interval: 10.9-14.8%), respectively. The most frequently detected and highest titer antibodies were specific for AdHu5. The results indicate that AdHu26 and AdC68 serve as more suitable vaccine vectors than AdHu5.

65 citations


Journal ArticleDOI
TL;DR: Serum microRNA levels are significantly associated with multiple aspects of HBV infection and the biological meaning of the correlation between microRNA‐122 and HBsAg and should be investigated further.
Abstract: Hepatitis B virus (HBV) infection is associated with increased expression of microRNA-122. Serum microRNA-122 and microRNA-22 levels were analyzed in 198 patients with chronic HBV who underwent liver biopsy and were compared with quantitative measurements of HBsAg, HBeAg, HBV DNA, and other clinical and histological findings. Levels of serum microRNA-122 and microRNA-22 were determined by reverse transcription-TaqMan PCR. Serum levels of microRNA-122 and microRNA-22 were correlated (R(2) = 0.576; P < 0.001), and both were elevated in chronic HBV patients. Significant linear correlations were found between microRNA-122 or microRNA-22 and HBsAg levels (R(2) = 0.824, P < 0.001 and R(2) = 0.394, P < 0.001, respectively) and ALT levels (R(2) = 0.498, P < 0.001 and R(2) = 0.528, P < 0.001, respectively). MicroRNA-122 levels were also correlated with HBV DNA titers (R(2) = 0.694, P < 0.001 and R(2) = 0.421, P < 0.001). Levels of these microRNAs were significantly higher in HBeAg-positive patients compared to HBeAg-negative patients (P < 0.001 and P < 0.001). MicroRNA-122 levels were also lower in patients with advanced liver fibrosis (P < 0.001) and lower inflammatory activity (P < 0.025). These results suggest that serum micro-RNA levels are significantly associated with multiple aspects of HBV infection. The biological meaning of the correlation between microRNA-122 and HBsAg and should be investigated further.

63 citations


Journal ArticleDOI
TL;DR: Age, intravenous drug use, needle stick injury, transfusion before 1995, and tattoos were the independent risk factors of HCV infection.
Abstract: The epidemiological and clinical features of hepatitis C virus (HCV) infection in South Korea were examined in a prospective, multicenter cohort study that included 1,173 adult patients with positive results for anti-HCV antibody who completed a questionnaire survey on the risk factors for HCV infection from January 2007 to December 2011 at five university hospitals. The HCV cohort had a mean age of 55.4 years with 48.3% men, and diagnostic categories of acute hepatitis (n = 63, 5.3%), past infection (n = 37, 3.2%), chronic hepatitis (n = 777, 66.2%), cirrhosis of the liver (n = 179, 15.3%), and hepatocellular carcinoma (n = 117, 10.0%). The major HCV genotypes were genotype 1 (52.7%) and genotype 2 (45.3%). Liver biopsy was performed in 301 patients (25.7%), and 42.8% of the subjects received antiviral therapy against HCV. The behavioral risk factors possibly related to HCV infection were intravenous drug use (5%), needle stick injury (7%), blood transfusion before 1995 (19%), sexual relationship with more than three partners (28%), piercings (35%), tattoos (36%), surgery (43%), acupuncture (83%), diagnostic endoscopy (85%), and dental procedures (93%). Age, intravenous drug use, needle stick injury, transfusion before 1995, and tattoos were the independent risk factors of HCV infection. J Med. Virol. 85:1724–1733, 2013. © 2013 Wiley Periodicals, Inc.

62 citations


Journal ArticleDOI
TL;DR: VGCV may have clinical benefit in a subset of CFS patients independent of placebo effect, possibly mediated by immunomodulation and/or antiviral effect, and further investigation with longer treatment duration and a larger sample size is warranted.
Abstract: There is no known treatment for chronic fatigue syndrome (CFS). Little is known about its pathogenesis. Human herpesvirus 6 (HHV-6) and Epstein–Barr virus (EBV) have been proposed as infectious triggers. Thirty CFS patients with elevated IgG antibody titers against HHV-6 and EBV were randomized 2:1 to receive valganciclovir (VGCV) or placebo for 6 months in a double-blind, placebo-controlled trial. Clinical endpoints aimed at measuring physical and mental fatigue included the Multidimensional Fatigue Inventory (MFI-20) and Fatigue Severity Scale (FSS) scores, self-reported cognitive function, and physician-determined responder status. Biological endpoints included monocyte and neutrophil counts and cytokine levels. VGCV patients experienced a greater improvement by MFI-20 at 9 months from baseline compared to placebo patients but this difference was not statistically significant. However, statistically significant differences in trajectories between groups were observed in MFI-20 mental fatigue subscore (P = 0.039), FSS score (P = 0.006), and cognitive function (P = 0.025). VGCV patients experienced these improvements within the first 3 months and maintained that benefit over the remaining 9 months. Patients in the VGCV arm were 7.4 times more likely to be classified as responders (P = 0.029). In the VGCV arm, monocyte counts decreased (P < 0.001), neutrophil counts increased (P = 0.037) and cytokines were more likely to evolve towards a Th1-profile (P < 0.001). Viral IgG antibody titers did not differ between arms. VGCV may have clinical benefit in a subset of CFS patients independent of placebo effect, possibly mediated by immunomodulation and/or antiviral effect. Further investigation with longer treatment duration and a larger sample size is warranted. J. Med. Virol. 85:2101–2109, 2013. © 2013 The Authors. Journal of Medical Virology Published by Wiley Periodicals, Inc.

61 citations


Journal ArticleDOI
TL;DR: Positive feedback suppression of HBV replication by the miR‐17‐92 polycistron is demonstrated by the direct interaction between these two miRNAs and target regions in HBV transcripts.
Abstract: MicroRNAs (miRNAs) regulate post-transcriptional gene expression in various physiological and pathological processes, including viral infections. The miR-17-92 cluster encodes six miRNAs (miR-17-5p, miR-18a, miR-19a, miR-19b, miR-20a, and miR-92a-1) which are transactivated by c-Myc. Because hepatitis B virus transactivates c-Myc, the interaction between the miR-17-92 cluster and HBV replication was examined in this study. Inducing HBV replication in a human hepatoma cell line increased miR-17-5p, miR-20a and miR-92a-1 expression. HBV-induced overexpression of miR-17-92 was reversed by c-Myc knockdown. Antisense peptide nucleic acids against miR-20a and miR-92a-1 augmented HBV replication. A computational analysis yielded potential binding sites for miR-20a and miR-92a-1 in the HBV genome. The direct interaction between these two miRNAs and target regions in HBV transcripts was confirmed by luciferase reporter analysis. These results demonstrated negative feedback suppression of HBV replication by the miR-17-92 polycistron.

Journal ArticleDOI
TL;DR: RT‐qPCR is a useful method to characterize shedding patterns in children with symptomatic and asymptomatic rotavirus infection and no difference was noted between the G and P genotypes of samples collected at onset of infection and during the shedding period.
Abstract: Reverse transcription-real-time polymerase chain reaction (RT-qPCR) for the VP6 gene was used to study group A rotavirus shedding in children with symptomatic and asymptomatic rotavirus infection. Sequential stool samples (n = 345) from 10 children with rotavirus associated diarrhea and from five children (n = 161) with asymptomatic rotavirus infection were collected over a period of 2 months. A RT-qPCR assay on the samples using a rotavirus VP6 plasmid standard demonstrated high reproducibility, with an inter-assay coefficient of variation (CV) of 1.40–2.97% and an intra-assay CV of 0.03–3.03%. The median duration of shedding was longer in children with diarrhea compared to asymptomatic children (24 days vs. 18 days; P = 0.066). The median quantitation cycle (Cq) at presentation in symptomatic children was 17.21 compared to 30.98 in asymptomatic children (P = 0.086). The temporal pattern in symptomatic children consisted of a high initial viral shedding coinciding with the duration of diarrhea, followed by a rapid fall, and then a small increase in secondary shedding 21 days later. Compared to children with rotavirus diarrhea, those with asymptomatic infection shed lower quantities of virus throughout the observation period. No difference was noted between the G and P genotypes of samples collected at onset of infection and during the shedding period. Shedding was intermittent in a subset of children in both groups. RT-qPCR is a useful method to characterize shedding patterns. J. Med. Virol. 85:1661–1668, 2013. © 2013 Wiley Periodicals, Inc.

Journal ArticleDOI
TL;DR: Chronic HEV infection in kidney transplant recipients progress to chronicity in most cases and might be complicated by early liver cirrhosis, but ribavirin may be required if reduction of the immunosuppressant dose is not associated with HEV clearance or is inappropriate for the patient management.
Abstract: Hepatitis E virus (HEV) is an emerging cause of acute hepatitis in Europe, particularly in southern France, and HEV is a new causative agent of chronic hepatitis and cirrhosis in immunocompromised patients. However, the data regarding HEV infection after kidney transplantation are still scarce with respect to the clinical issues that have been raised, and no study has specifically focused on kidney transplant recipients. This study described the clinical features and outcomes of HEV infections in a cohort of kidney transplant recipients living in southeastern France. The epidemiological, clinical, and virological characteristics of HEV infections diagnosed by PCR over a 53-month period were retrospectively analyzed in a cohort of 1,350 kidney transplant recipients monitored at the Marseille University Hospital. Sixteen HEV infections were diagnosed, all of which were autochthonous and involved genotype 3 viruses (HEV-3). Chronic infections occurred in 80% of these patients and resolved in half of the cases after a median time of 39 months. The rate of HEV clearance was 54% after a decrease in the dose of immunosuppressants. One patient developed liver cirrhosis 14 months after infection and experienced acute rejection after a decrease in the dose of immunosuppressants. Autochthonous HEV-3 infections in kidney transplant recipients progress to chronicity in most cases and might be complicated by early liver cirrhosis. Chronic HEV infection can resolve following the reduction of immunosuppressive therapy, but ribavirin may be required if reduction of the immunosuppressant dose is not associated with HEV clearance or is inappropriate for the patient management. J. Med. Virol. 85:462–471, 2013. © 2012 Wiley Periodicals, Inc.

Journal ArticleDOI
TL;DR: The viral load of HEV was significantly higher in the pregnant patients with acute liver failure compared to the pregnant women with acute viral hepatitis and also men and could be one of the factors responsible for the severity of the infection during pregnancy.
Abstract: The incidence and mortality in pregnant women with acute liver failure caused by hepatitis E virus (HEV) is high. Data on the viral load of HEV during pregnancy are limited. The study was designed to determine the viral load of HEV and its association with the disease severity in patients with acute liver failure. A total of HEV related 163 patients with acute liver failure which included 105 pregnant, 46 non-pregnant women and girls and 12 men and 730 patients with acute viral hepatitis which comprised of 220 pregnant women; 282 non-pregnant women and girls and 228 men were included. Viral load was measured by real-time PCR. Comparison was made between the pregnant and non-pregnant women. HEV RNA was detectable in 265 patients (142 pregnant; 75 non-pregnant and 48 men) and 104 patients with acute liver failure (64 pregnant, 34 non-pregnant and 6 men). The viral load of HEV in pregnant women with acute liver failure and acute viral hepatitis was significantly higher 129,984.0 ± 103,104.17 and 768.92 ± 1,105.40 copies/ml, respectively compared to the non-pregnant women which was 189.2 ± 225 and 12.73 ± 7.8 copies/ml (P < 0.0001). The viral load of HEV was also significantly higher in the pregnant patients with acute liver failure compared to the pregnant women with acute viral hepatitis and also men (P < 0.0001). High viral load of HEV during pregnancy could be one of the factors responsible for the severity of the infection during pregnancy. J. Med. Virol. 85:620–626, 2013. © 2012 Wiley Periodicals, Inc.

Journal ArticleDOI
TL;DR: It is suggested that HHV‐6 may act as a pathogenic factor predisposing patients to the development of autoimmune connective tissue diseases or, conversely, that these disorders may predispose patients to HHv‐6 reactivation.
Abstract: Viral infections have been associated with autoimmune connective tissue diseases. To evaluate whether active infection by Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus (HHV)-6, -7, -8, as well as parvovirus B19 (B19V) occur in patients with autoimmune connective tissue diseases, viral DNA loads were assessed in paired samples of serum and peripheral blood mononuclear cells (PBMCs) of 115 patients affected by different disorders, including systemic sclerosis, systemic, and discoid lupus erythematosus, rheumatoid arthritis, and dermatomyositis. Two additional groups, patients affected by inflammatory diseases (n=51) and healthy subjects (n=58) were studied as controls. The titers of anti-HHV-6 and anti-EBV antibodies were also evaluated. Cell-free HHV-6 serum viremia was detected in a significantly higher proportion of connective tissue diseases patients compared to controls (P<0.0002); a significant association between HHV-6 reactivation and the active disease state was found only for lupus erythematosus (P=0.021). By contrast, the rate of cell-free EBV viremia was similar in patients and controls groups. Cell-free CMV, HHV-8, and B19V viremia was not detected in any subject. Anti-HHV-6 and anti-EBV early antigen IgG titers were both significantly higher in autoimmune diseases patients as compared to healthy controls, although they were not associated with the presence of viremia. EBV, HHV-6, -7 prevalence and viral load in PBMCs of patients with connective tissue diseases and controls were similar. These data suggest that HHV-6 may act as a pathogenic factor predisposing patients to the development of autoimmune connective tissue diseases or, conversely, that these disorders may predispose patients to HHV-6 reactivation.

Journal ArticleDOI
TL;DR: In this article, a randomized, double-blinded, placebo-controlled 28-week intervention study was conducted to evaluate the effects of probiotic intervention on the presence of respiratory viruses in children attending day care.
Abstract: Limited data are available on the effects of probiotics on the nasopharyngeal presence of respiratory viruses in children attending day care. In this substudy of a randomized, double-blinded, placebo-controlled 28-week intervention study, nasopharyngeal swab samples were collected, on visits to a physician due to symptoms of infection, from children receiving control milk (N = 97) and children receiving the same milk supplemented with probiotic Lactobacillus rhamnosus GG (N = 97). The presence of 14 respiratory viruses was assessed by PCR methods, and viral findings were compared with symptom prevalences in the intervention groups. Rhinovirus was identified in 28.6% of 315 swab samples, followed by respiratory syncytial virus (12.4%), parainfluenza virus 1 (12.1%), enterovirus (8.9%), influenza A(H1N1)pdm09 (7.9%), human bocavirus 1 (3.8%), parainfluenza virus 2 (3.2%), adenovirus (2.9%), and influenza A(H3N2) (0.6%). The children in the probiotic group had less days with respiratory symptoms per month than the children in the control group (6.48 [95% CI 6.28–6.68] vs. 7.19 [95% CI 6.98–7.41], P < 0.001). Probiotic intervention did not reduce significantly the occurrence of the examined respiratory viruses, or have an effect on the number of respiratory symptoms observed at the time of a viral finding. Rhinovirus, respiratory syncytial virus, and parainfluenza virus 1 were the most common respiratory viruses in symptomatic children. Children receiving Lactobacillus rhamnosus GG had fewer days with respiratory symptoms than children in the control group, although probiotic intervention was not effective in reducing the amount of viral findings or the respiratory symptoms associated with viral findings. J. Med. Virol. 85:1632–1638, 2013. © 2013 Wiley Periodicals, Inc.

Journal ArticleDOI
TL;DR: Combined antiviral therapy (pegylated IFN plus ribavirin) gives satisfactory response in more than the half of patients with symptomatic mixed cryoglobulinemia associated with HCV, a systematic review of the literature with a meta‐analysis of clinical studies found.
Abstract: Hepatitis C virus (HCV) infection may be associated with extra-hepatic illness including mixed cryoglobulinemia. Evidence on HCV-related mixed cryoglobulinemia in the non-transplantation setting exists even if its appropriate management remains unclear. The cornerstone of treatment for symptomatic HCV-associated mixed cryoglobulinemia is antiviral therapy but little is known about its activity. A systematic review of the literature with a meta-analysis of clinical studies was performed in order to assess efficacy and safety of combination antiviral therapy for symptomatic HCV-associated mixed cryoglobulinemia in non-immunosuppressed individuals. The random effects model of DerSimonian and Laird was used, with heterogeneity and sensitivity analyses. The primary outcome was sustained virological response (as a measure of efficacy), and the secondary outcome was the rate of patients stopping (or dose reducing) antiviral agents (as a measure of tolerability). Ten clinical studies (300 unique patients) were identified; the rate of baseline kidney involvement ranged between 4% and 39%. The summary estimate of frequency of sustained viral response was 0.42 with a 95% confidence interval (CI) of 0.31; 0.54 (random effects model). Significant heterogeneity occurred (P = 0.00001; I(2) = 77.6%). Stratified analysis showed higher efficacy in those studies using combination therapy with pegylated-than conventional IFN; the summary estimate of sustained viral response being 0.52 (95% CI, 0.40; 0.63) and 0.32 (95% CI, 0.15; 0.49), respectively. There was good association between viral and clinical response, weighted K 0.634 (95% CI, 0.455; 0.814), by a meta-analysis at individual level on a subset of reports (n = 3; 74 unique patients). The summary estimate of frequency of patients stopping (or dose reducing) antiviral agents was 0.15 (95% CI, 0.08; 0.21); no heterogeneity occurred (P = 0.05; I(2) = 51%). In summary, combination antiviral therapy (pegylated IFN plus ribavirin) gives satisfactory response in more than the half of patients with symptomatic mixed cryoglobulinemia associated with HCV. HCV-related mixed cryoglobulinemia is uncommon in developed countries and this clearly hampers randomized controlled clinical trials aimed to evaluate efficacy and safety of antiviral therapy in non-immunosuppressed individuals.

Journal ArticleDOI
TL;DR: The data obtained in this study suggest that primary DENV infection cases exist certainly among DHF/DSS cases in Myanmar, and that additional mechanism(s) aside from the antibody‐dependent enhancement mechanism could have influenced the clinical severity inDHF/ DSS cases.
Abstract: In Myanmar, dengue fever (DF)/dengue hemorrhagic fever (DHF) is one of the leading causes of morbidity and mortality among children. From Pyinmana Hospital in 2004 and Mandalay Children Hospital in 2006, 160 patients diagnosed clinically to have DHF/dengue shock syndrome (DSS) were examined for immunoglobulin M (IgM) and IgG levels. A focus reduction neutralization test was also used to determine primary or secondary dengue virus (DENV) infection. By using IgM-capture ELISA, 139 cases were confirmed as DENV infections. Of these IgM-positives, 94 samples were collected 7-24 days from the onset of illness, to which 13 (14%) and 81 (86%) were determined to be primary and secondary DENV infections, respectively. The 13 primary DENV infection cases were spread among the various severity groups (DHF grade I-IV and DSS) and represented age groups ranging from <1 year of age to 9 years of age. The patients in these primary infection cases showed a remarkably high IgM with a low IgG titer response compared with the secondary infection cases. No significant differences were observed in IgG titers with clinical severity. The data obtained in this study suggest that primary DENV infection cases exist certainly among DHF/DSS cases in Myanmar, and that additional mechanism(s) aside from the antibody-dependent enhancement mechanism could have influenced the clinical severity in DHF/DSS cases.

Journal ArticleDOI
TL;DR: The “in‐house” method enabled HCV to be subtyped accurately with the detection, in some cases, of recombinant viruses or dual HCV infections.
Abstract: Hepatitis C virus (HCV) genotype determination is required in clinical practice to establish the dose and duration of antiviral treatment. Although subtype identification does not impact on current therapy this is changing with new specific inhibitors of HCV enzymes and functions which are becoming available worldwide. These new drugs may yield different antiviral responses and resistance profiles. Accurate classification of HCV genotype and subtype is therefore crucial. An "in-house" method was developed for improving HCV subtyping and the results were compared with a second-generation line probe assay (LiPA) used extensively in Portugal. Phylogenetic analysis was undertaken of the C/E1 and NS5B genomic regions of HCV isolated from 72 prisoners with chronic HCV infection and from reference samples. Although LiPA is considered to be a good method for genotyping, HCV was subtyped in only 47.2% of cases compared with 95.8% of cases by the "in-house" method. Molecular data for both C/E1 and NS5B regions were obtained in 88.9% of the samples. Two out of 23 cases of subtype 1a were misclassified as subtype 1b by LiPA. A putative recombinant like RF1_2k/1b, two potential inter-genotypic recombinants 1b/4a and 3a/4a, and also a potential intra-genotypic recombinant 2q/2k in C/E1 and 2k/2a in NS5B were also identified. The "in-house" method enabled HCV to be subtyped accurately with the detection, in some cases, of recombinant viruses or dual HCV infections. Near full-length genomic analysis to characterize these potential recombinant viruses is planned.

Journal ArticleDOI
TL;DR: It is suggested that CMV may shape immune response to neoantigens among younger persons; these groups should be included in future studies of immunosenescence and CMV.
Abstract: Human cytomegalovirus (CMV) infection has been implicated in immunosenescence. To examine the influence of CMV on ability of healthy adults to respond to a novel influenza antigen, the rate of seroconversion and the magnitude of titers to pandemic 2009 H1N1 vaccine was assessed. The clinical trial was stratified by age; 52 persons aged 18–64 and 55 aged 65 and older were enrolled. Among the younger group, 33% had CMV antibody compared with 62% among the older group No differences by CMV seropositivity in the proportion of participants achieving a seroprotective titer 21 days following the second immunization were noted. However, the geometric mean titer in hemagglutination inhibition assay was significantly higher among CMV seronegative younger participants compared with CMV seropositive younger participants (385 vs 142, p=0.013). In contrast, among the older group, CMV serostatus was not associated with differential antibody titers (53 vs 63, p=0.75). These data suggest that CMV may shape immune response to neoantigens among younger persons; these groups should be included in future studies of immunosenescence and CMV.

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TL;DR: The present study identified HCV NS2 as a potent interferon antagonist, and describes an explanation of how NS2 downregulates the major signaling pathways involved in the development of host innate antiviral responses.
Abstract: Hepatitis C virus (HCV) encodes for several proteins that can interfere with host cell signaling and antiviral response. Previously, serine protease NS3/4A was shown to block host cell interferon (IFN) production by proteolytic cleavage of MAVS and TRIF, the adaptor molecules of the RIG-I and TLR3 signaling pathways, respectively. This study shows that another HCV protease, NS2 can interfere efficiently with cytokine gene expression. NS2 and its proteolytically inactive mutant forms were able to inhibit type I and type III IFN, CCL5 and CXCL10 gene promoters activated by Sendai virus infection. However, the CXCL8 gene promoter was not inhibited by NS2. In addition, constitutively active RIG-I (ΔRIG-I), MAVS, TRIF, IKKe, and TBK1-induced activation of IFN-β promoter was inhibited by NS2. Cotransfection experiments with IKKe or TBK1 together with interferon regulatory factor 3 (IRF3) and HCV expression constructs revealed that NS2 in a dose-dependent manner inhibited IKKe and especially TBK1-induced IRF3 phosphorylation. GST pull-down experiments with GST-NS2 and in vitro-translated and cell-expressed IKKe and TBK1 demonstrated direct physical interactions of the kinases with NS2. Further evidence that the IKKe/TBK1 kinase complex is the target for NS2 was obtained from the observation that the constitutively active form of IRF3 (IRF3-5D) activated readily IFN-β promoter in the presence of NS2. The present study identified HCV NS2 as a potent interferon antagonist, and describes an explanation of how NS2 downregulates the major signaling pathways involved in the development of host innate antiviral responses.

Journal ArticleDOI
TL;DR: It is shown that CVB5‐associated aseptic meningitis is an emerging concern in China and two distinct lineages were observed for the 17 isolates in the phylogenetic tree, indicating that at least two different transmission chains ofCVB5 were responsible for this outbreak.
Abstract: In 2009, a major outbreak of aseptic meningitis was noted in Linyi city, Shandong province, China. From June to September 2009, a total of 2,104 cases were involved in this outbreak, and 98.6% of patients were <16 years of age. To determine the pathogen of the outbreak, 42 cerebrospinal fluid specimens collected from aseptic meningitis cases were tested for cell culture, and 17 (40.5%) enteroviruses were isolated and identified as Coxsackievirus B5 (CVB5). Homologous comparison indicated that these isolates had 0-7.7% nucleotide divergence with each other. Phylogenetic reconstruction showed global CVB5 could be separated into four genogroups, and all Linyi CVB5 isolates belonged to the genogroup C which had been circulating for recent 27 years in Asia and Europe. Interestingly, two distinct lineages were observed for the 17 isolates in the phylogenetic tree, indicating that at least two different transmission chains of CVB5 were responsible for this outbreak. This study showed that CVB5-associated aseptic meningitis is an emerging concern in China.

Journal ArticleDOI
TL;DR: The PCR‐based assay utilized in this study proved highly sensitive and specific for HPV‐DNA detection and genotyping in urine samples and suggest that a urine-based assay would be a suitable and effective tool for epidemiological surveillance and, most of all, screening programs.
Abstract: Human papillomavirus (HPV) testing has been proposed as a means of replacing or supporting conventional cervical screening (Pap test). However, both methods require the collection of cervical samples. Urine sample is easier and more acceptable to collect and could be helpful in facilitating cervical cancer screening. The aim of this study was to evaluate the sensitivity and specificity of urine testing compared to conventional cervical smear testing using a PCR-based method with a new, designed specifically primer set. Paired cervical and first voided urine samples collected from 107 women infected with HIV were subjected to HPV-DNA detection and genotyping using a PCR-based assay and a restriction fragment length polymorphism method. Sensitivity, specificity, Positive Predictive Value (PPV), and Negative Predictive Value (NPV) were calculated using the McNemar's test for differences. Concordance between tests was assessed using the Cohen's unweighted Kappa (k). HPV DNA was detected in 64.5% (95% CI: 55.1-73.1%) of both cytobrush and urine samples. High concordance rates of HPV-DNA detection (k = 0.96; 95% CI: 0.90-1.0) and of high risk-clade and low-risk genotyping in paired samples (k = 0.80; 95% CI: 0.67-0.92 and k = 0.74; 95% CI: 0.60-0.88, respectively) were observed. HPV-DNA detection in urine versus cervix testing revealed a sensitivity of 98.6% (95% CI: 93.1-99.9%) and a specificity of 97.4% (95% CI: 87.7-99.9%), with a very high NPV (97.4%; 95% CI: 87.7-99.9%). The PCR-based assay utilized in this study proved highly sensitive and specific for HPV-DNA detection and genotyping in urine samples. These data suggest that a urine-based assay would be a suitable and effective tool for epidemiological surveillance and, most of all, screening programs.

Journal ArticleDOI
TL;DR: This largest study to date of norovirus infection in African children indicates the potential role of paediatric surveillance in predicting the emergence of Norovirus strains with global epidemic potential.
Abstract: Despite the increasing recognition of noroviruses as major pathogens associated with community-acquired diarrhoea in children, there are few studies from Africa. Long-term surveillance studies of rotavirus gastroenteritis in Malawian children have provided an opportunity to undertake a study of the importance and epidemiological features of norovirus infection in this population. Faecal specimens were collected from children <5 years of age admitted to hospital with acute diarrhoea, as well as from a comparison group of diarrhoea-free children, in Blantyre, Malawi between 1997 and 2007. Norovirus was detected using real-time PCR and strains genotyped by nucleotide sequence analysis. Norovirus was detected in 220/1,941 (11.3%) faecal specimens, comprising genogroup GI (1.8%), GII (9.4%) and mixed GI/GII (0.1%). The median age of children with norovirus was 6 months (range, 0-48 months). Norovirus was detected throughout the year, with peaks at the end of the rainy season (March) and towards the end of the dry season (August-November). Norovirus GII.4 was the most commonly detected genotype accounting for 70% of strains characterised, followed by GII.2 (6%), GII.6 (4%) and GII.12 (4%). Sub typing of GII.4 noroviruses demonstrated local circulation of strains prior to their subsequent detection in association with global epidemics of gastroenteritis. The prevalence of norovirus in children without diarrhoea was similar to the level in cases. This largest study to date of norovirus infection in African children indicates the potential role of paediatric surveillance in predicting the emergence of norovirus strains with global epidemic potential.

Journal ArticleDOI
TL;DR: Interestingly, the antiviral activity of K4K20S4 was effective on both acyclovir‐resistant and ‐sensitive viruses, and can be considered a promising candidate for future application as a therapeutic virucidal agent for the treatment of herpes viruses.
Abstract: Herpes simplex virus (HSV) infections have become a public health problem worldwide. The emergence of acyclovir-resistant viral strains and the failure of vaccination to prevent herpetic infections have prompted the search for new antiviral drugs. Accordingly, the present study was undertaken to synthesize chemically and evaluate Dermaseptin S4 (S4), an anti-microbial peptide derived from amphibian skin, and its derivatives in terms of anti-herpetic activity. The effects of biochemical modifications on their antimicrobial potential were also investigated. The peptides were incubated together with HSV-2 on target cells under various conditions, and the antiviral effects were examined via a cell metabolic labeling method. The findings revealed that DS4 derivatives elicited concentration-dependent antiviral activity at micromole concentrations. The biochemical modifications of S4 allowed for the reduction of peptide cytotoxicity without altering antiviral activity. Dermaseptins were added at different times during the viral cycle to investigate the mode of antiviral action. At the highest noncytotoxic concentrations, most of the tested derivatives were noted to exhibit high antiviral activity particularly when pre-incubated with free herpes viruses prior to infection. Among these peptides, K4K20S4 exhibited the highest antiviral activity against HSV-2 sensitive and resistant strains. Interestingly, the antiviral activity of K4K20S4 was effective on both acyclovir-resistant and -sensitive viruses. The findings indicate that K4K20S4 can be considered a promising candidate for future application as a therapeutic virucidal agent for the treatment of herpes viruses. J. Med. Virol.

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TL;DR: The approximately 10% relative frequency of G12P[6] strains detected in this study suggests that this strain is emerging in Cameroon and should be monitored carefully as rotavirus vaccine is implemented in this country, as it shares neither G‐ nor P‐type specificity with strains in the RotaTeq® and Rotarix® vaccines.
Abstract: In this study the emergence of rotavirus A genotype G12 in children <5 years of age is reported from Cameroon during 2010/2011. A total of 135 human stool samples were P and G genotyped by reverse transcriptase PCR. Six different rotavirus VP7 genotypes were detected, including G1, G2, G3, G8, G9, and G12 in combinations with P[4], P[6] and P[8] VP4 genotypes. Genotype G12 predominated in combination with P[8] (54.1%) and P[6] (10.4%) genotypes followed by G1P[6] (8.2%), G3P[6] (6.7%), G2P[4] (5.9%), G8P[6] (3.7%), G2P[6] (0.7%), G3P[8] (0.7%), and G9P[8] (0.7%). Genotype P[6] strains in combination with various G-types represented a substantial proportion (N = 44, 32.6%) of the genotyped strains. Partially typed strains included G12P[NT] (2.2%); G3P[NT] (0.7%); G(NT)P[6] (1.5%); and G(NT)P[8] (0.7%). Mixed infections were found in five specimens (3.7%) in several combinations including G1 + G12P[6], G2 + G3P[6] + P[8], G3 + G8P[6], G3 + G12P[6] + P[8], and G12P[6] + P[8]. The approximately 10% relative frequency of G12P[6] strains detected in this study suggests that this strain is emerging in Cameroon and should be monitored carefully as rotavirus vaccine is implemented in this country, as it shares neither G- nor P-type specificity with strains in the RotaTeq® and Rotarix® vaccines. These findings are consistent with other recent reports of the global spread and increasing epidemiologic importance of G12 and P[6] strains. J. Med. Virol. 85:1485–1490, 2013. © 2013 Wiley Periodicals, Inc.

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TL;DR: It is suggested that HBV and HCV infection is common among hemodialysis patients in Yogyakarta, and probably occurs through nosocomial infection, and implementation of strict infection‐control programs is necessary in he modialysis units in Indonesia.
Abstract: Hemodialysis patients are at an increased risk of acquiring hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. However, the prevalence of hepatitis viral infection and its genotype distribution among hemodialysis patients in Indonesia are unclear. In order to investigate these issues and the possibility of nosocomial transmission, 161 hemodialysis patients and 35 staff members at one of the hemodialysis unit in Yogyakarta, Indonesia, were tested for serological and virological markers of both viruses. HBV surface antigen (HBsAg) was detected in 18 patients (11.2%) and in two staff members (5.7%). Anti-HCV was detected in 130 patients (80.7%) but not in any staff members. Occult HBV and HCV infection were detected in 21 (14.7%) and 4 (12.9%) patients, respectively. The overall prevalence rates of HBV and HCV infection among patients were 24.2% and 83.2%, respectively. HCV infection was independently associated with hemodialysis duration and the number of blood transfusions. Phylogenetic analysis revealed that 23 of 39 tested HBV strains (59%) were genotype B, 11 (28.2%) were genotype C, and 5 (12.8%) were genotype A. HCV genotype 1a was dominant (95%) among 100 tested HCV strains. Nosocomial transmission was suspected because the genotype distribution differed from that of the general population in Indonesia, and because the viral genomes of several strains were identical. These findings suggest that HBV and HCV infection is common among hemodialysis patients in Yogyakarta, and probably occurs through nosocomial infection. Implementation of strict infection-control programs is necessary in hemodialysis units in Indonesia.

Journal ArticleDOI
TL;DR: A significant decrease in HCV and HBV prevalences in Chinese dialysis units showed that infection control measures were effective, however, because nosocomial transmissions persist, strict adherence to infection Control measures should be emphasized to reduce the risk of transmission.
Abstract: Hemodialysis patients are at risk for hepatitis C and B virus infections. This study investigated the prevalences and risk factors of HCV and HBV infection and the distribution of HCV genotypes among hemodialysis patients and their spouses. From August to November 2011, a cross-sectional study was conducted on 20 hemodialysis units in Beijing to investigate prevalences and risk factors for markers of HCV and HBV among 2,120 patients and 409 spouses. In hemodialysis patients, prevalences of anti-HCV, HCV RNA, and hepatitis B surface antigen (HBsAg) were 6.1%, 4.6%, and 7.0%, respectively. The prevalence of HCV antibodies among spouses was 0.5%, of HCV RNA was 0.2%, and of HBsAg was 4.2%. Risk factors for HCV infection were dialysis duration, blood transfusion, and attending more than one dialysis unit. HBV infection was independently associated with age, family member with hepatitis infection, gender, and surgery. The predominant HCV genotypes were 1b (89.0%) and 2a (7.7%), and genotypes 3a, 3b, and 6a were each 1.1%. A significant decrease in HCV and HBV prevalences in Chinese dialysis units showed that infection control measures were effective. However, because nosocomial transmissions persist, strict adherence to infection control measures should be emphasized to reduce the risk of transmission.

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TL;DR: Hepatitis E virus antigen detection was found to be an early diagnostic marker of acute infection and anti‐HEV IgM was the main diagnostic indicator of infection.
Abstract: Hepatitis E virus (HEV) is implicated in many outbreaks of viral hepatitis in the Indian subcontinent. The conventional diagnosis of such outbreaks rests on the detection of anti-HEV IgM antibodies. However, IgM antibodies develop after 4-5 days of infection. An early-diagnostic marker is imperative for timely diagnosis of the outbreak and also initiation of control measures. This study aimed to determine the use of hepatitis E virus antigen detection as an early diagnostic marker in an outbreak in comparison to anti-HEV IgM and RT-PCR analyses. Forty samples were collected during a suspected outbreak of viral hepatitis due to HEV. A total of 36 samples were positive for one or more HEV markers. The positivity for anti-HEV IgM, HEV antigen, and RT-PCR was 91.6%, 69.4%, and 47.2% respectively. RT-PCR and HEV antigen detection gave the highest positive results (100%) in the first 3 days of illness. Positive HEV PCR declined to 54% by Days 4-7, whereas HEV antigen and IgM detection were 88% and 100%, respectively. Sequencing of representative HEV samples indicated that the strains responsible for this outbreak belonged to genotype I, subtype 1a. HEV antigen was found to be an early diagnostic marker of acute infection. HEV antigen was detected in three additional cases in the early phase (1-3 days), and they had no detectable anti-HEV IgM antibodies. These three samples were also positive for HEV RNA. After Day 7, anti-HEV IgM was the main diagnostic indicator of infection.

Journal ArticleDOI
TL;DR: The seroprevalence of HBsAg and anti‐HBs in Korea varies significantly by age, sex and geographical location and coexisted in 2.9% ofHBsAg‐positive subjects, suggesting continuous monitoring of seroepidemiology may facilitate the eventual eradication of HBV infection.
Abstract: Hepatitis B virus (HBV) infection is the major cause of chronic liver disease in Korea. This study investigated the seroprevalence of HBV infection with an emphasis on the coexistence of hepatitis B surface antigen (HBsAg) and antibody (anti-HBs). In all, 290,212 people undergoing health check-up examinations in 29 institutions during 2009 were recruited. The crude seroprevalences of HBsAg and anti-HBs was adjusted by age, sex, and geographic area using the 2009 estimated population of Korea. The adjusted seroprevalences of HBsAg and anti-HBs was 4.0% and 73.5%, respectively. Males showed higher HBsAg positivity and lower anti-HBs positivity than females (P < 0.001). HBsAg positivity increased with age from 3.5% in people 20–29 years old to 4.8% in people 40–49 years old, followed by a decrease in people ≥50 years old. HBsAg positivity in Southern provinces (4.5%) including Jeju (5.9%), was significantly higher than that in Central provinces (3.6%; P < 0.001). Interestingly, HBsAg and anti-HBs coexisted in 0.1% of the total subjects and in 2.9% of the HBsAg-positive group, showing distinct age distribution and higher alanine aminotransferase levels than those of the group positive for only HBsAg. In conclusion, the seroprevalence of HBsAg and anti-HBs in Korea varies significantly by age, sex and geographical location and coexisted in 2.9% of HBsAg-positive subjects. Continuous monitoring of seroepidemiology may facilitate the eventual eradication of HBV infection. J. Med. Virol. 85:1327–1333, 2013. © 2013 Wiley Periodicals, Inc.