Explore the vast range of titles available.

Protective antibody levels are critical for protection from severe enterovirus 71 infection. However, little is known about the specificities and functional properties of the enterovirus 71-specific antibodies induced by natural infection in humans. Here we characterize 191 plasmablast-derived monoclonal antibodies from three enterovirus 71-infected children, each of whom shows a distinct serological response. Of the 84 enterovirus 71-specific antibodies, neutralizing antibodies that target the rims and floor of the capsid canyon exhibit broad and potent activities at the nanogram level against viruses isolated in 1998–2016. We also find a subset of infected children whose enterovirus 71-specific antibodies are focused on the 3- and 2-fold plateau epitopes localized at the margin of pentamers, and this type of antibody response is associated with lower serum titers against recently circulating strains. Our data provide new insights into the enterovirus 71-specific antibodies induced by natural infection at the serological and clonal levels. Enterovirus 71 is a leading cause of hand-foot-and-mouth disease and herpangina. Here, the authors characterize a large panel of plasmablast-derived IgG mAbs that target the capsid of EV71 to identify neutralizing antibodies induced by natural infection.

Herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) are common human pathogens and might cause severe illness. Following primary infection, the viruses establish lifelong latent infection and are transmitted by close contact, both sexual and nonsexual. However, the information about the seroprevalence of HSV-1 and HSV-2 across all age groups is limited. Residual sera collected during the nationwide serosurvey in 2007 in Taiwan were selected for the study. The enzyme-linked immunosorbent assay was used to detect anti-HSV-1 and anti-HSV-2 type-specific glycoprotein IgG. Demographics and personal health data were used for risk analysis. A total of 1411 and 1072 serum samples were included for anti-HSV-1 and anti-HSV-2 seroprevalence analysis, respectively. The weighted overall seroprevalence was 63.2% for HSV-1, and 7.7% for HSV-2, respectively. The HSV-1 seropositive rate was 19.2% for those less than 5 years old, increased to 46.4% for those aged 5-13 years, 60.9% for those aged 14-29 years, and reached as much as 95.0% for those aged over 30 years. In contrast, the HSV-2 seropositve rate was 1.6% for those less than 30 years old, rose to 10.1% for those age 30-39 years, and was up to 31.2% for those aged over 60 years. A significantly higher HSV-2 seropositive rate was noted in females than males aged over 40 years (26.3% v.s. 16.8%), and the overall HSV-2 seropositive rate was almost twice higher in females than males. Smoking history, drinking habit, and educational level were associated with the HSV-1 seropositivity. Female gender and rural residence were independent factors for the HSV-2 seropositivity. An obvious increase of primary HSV-1 infection occurred in late adolescents and young adults, joined by the rise of HSV-2 infection in middle-aged adults, especially females. The acquistion and transmission of HSV warrant further studies in the susceptible population.

Enterovirus A71 (EV-A71) infections are a major Asia-Pacific health issue. However, this infection can cause serious and potentially fatal neurological issues. We attempt to explain EV-A71's molecular virology, epidemiology, and recombination events in this review. The clinical and neurological signs of EV-A71 infections are well documented. The review discusses EV-A71 central nervous system infections' causes, diagnostic criteria, treatment choices, and prognosis. Some consequences are aseptic meningitis, acute flaccid paralysis, and acute transverse myelitis. These problems' pathophysiology and EV-A71's central nervous system molecular processes are examined in the review. EV-A71 infections must be diagnosed accurately for therapy. No particular antiviral medications exist for EV-A71 infections, thus supportive care is the main treatment. The study emphasises addressing symptoms including temperature, dehydration, and pain to ease suffering. EV-A71 CNS infections have different prognoses depending on severity. The review discusses long-term effects and neurological sequelae of EV-A71 infections. In conclusion, Asia-Pacific public health is threatened by EV-A71 infections. This review helps prevent, diagnose, and treat EV-A71 infections by addressing the mechanisms, diagnostic criteria, treatment choices, and prognosis. This study fully examines the challenges and considerations of managing and treating EV-A71 infections. It also recommends future research and development to generate effective viral infection treatments.

•Associations between individual infections and childhood immune cell malignancies have been reported.•Some associations may be due to infection caused by malignancies already active prior to diagnosis.•Guided by unexplained lymph nodes, we found malignancies could be active years before diagnosis.•We also found increase in multiple infection presentations prior to malignancy diagnosis.•In all, most apparent associations could not be largely attributed to infection as a cause of malignancy. Infection is hypothesised as a contributory cause of childhood immune cell malignancies. Although some have reported associations between individual infections and immune cell malignancies, some could be spurious due to infections caused by malignancies that were already active prior to diagnosis. Identified from Taiwan Cancer Registry, ∼3000 children with four commonest immune cell malignancies diagnosed during 2001–2015 at age 1–20 years were identified and matched with 1:10 controls. Using logistic regression, we estimated the time-specific case-versus-control odds ratios of seven common infection presentations in their health records. We also compared recorded unexplained lymph nodes between cases and controls to explore for how long malignancy may be active prior to diagnosis. Unexplained lymph nodes were increasingly recorded months before the diagnosis of childhood leukaemias and years before the diagnosis of childhood lymphomas. When using p < 0.01 as a guide, large case-control differences in infection records were found mostly within 0–2 months prior to the diagnosis (15 out of 28 comparisons). Changes in odds ratios within 3–35 months (2 out of 28 comparisons) and case-control differences beyond 36+ months prior to diagnosis (7 out of 28 comparisons) was relatively small (∼10 % difference in leukaemias). Statistical power varied according to incidence of malignancy, incidence of infection records, and the age distribution. Immune cell malignancies were likely to be active some time before the diagnosis. Previous studies using conventional population-based methods may not be able to distinguish any small causal link between infection and immune cell malignancies from spurious associations.

Background. Antibodies play a major role in the protection against influenza virus in human. However, the antibody level is usually short-lived and the cellular mechanisms underlying influenza virus–specific antibody response to acute infection remain unclear. Methods. We studied the kinetics and magnitude of influenza virus–specific B-cell and serum antibody responses in relation to virus replication during the course of influenza infection in healthy adult volunteers who were previously seronegative and experimentally infected with seasonal influenza H1N1 A/Brisbane/59/07 virus. Results. Our data demonstrated a robust expansion of the virus-specific antibody-secreting cells (ASCs) and memory B cells in the peripheral blood, which correlated with both the throat viral load and the duration of viral shedding. The ASC response was obviously detected on day 7 post-infection when the virus was completely cleared from nasal samples, and serum hemagglutination-inhibition antibodies were still undetectable. On day 28 postinfection, influenza virus-specific B cells were further identified from the circulating compartment of isotype-switched B cells. Conclusions. Virus-specific ASCs could be the earliest marker of B-cell response to a new flu virus infection, such as H7N9 in humans.

Background. Enterovirus 71 (EV71) remains a leading pathogen for acute infectious diseases in children, especially in Asia. The cellular basis for establishing a virus-specific antibody response to acute EV71 infections is unclear in children. Methods. We studied the magnitude of virus-specific antibody-secreting cells (ASCs) and its relationship with serological response, clinical parameters, and virological parameters among children with laboratory-confirmed EV71 infection. Results. A potent EV71 genogroup B-and virus-specific ASC response was detected in the first week of illness among genotype B5 EV71-infected children. The cross-reactive EV71-specific ASC response to genogroup C viral antigens composed about 10% of the response. The EV71-specific ASC response in children aged ≥3 years produced immunoglobulin G predominantly, but immunoglobulin M was predominant in younger children. Proliferation marker was expressed by the majority of circulating ASCs in the acute phase of EV71 infection. Virus-specific ASC responses significantly correlated with throat viral load, fever duration, and serological genogroup-specific neutralization titer. Conclusions. The presence of a virus-specific ASC response serves an early cellular marker of an EV71-specific antibody response. Further detailed study of EV71-specific ASCs at the monoclonal level is crucial to delineate the specificity and function of antibody immunity in children.

BackgroundChildren with cancer, type 1 diabetes and other immune diseases often present initially with non-specific problems. It is unknown how long children with these conditions seek medical help before a diagnosis is reached.MethodsDuring the period 2002 to 2013, 7238 children aged 2–15 years diagnosed with cancer at seven sites, type 1 diabetes, and three other immune diseases were registered in the Taiwan National Health Insurance Catastrophic Illness Database. Their healthcare visit records in the year before diagnosis were extracted and compared to the records of matched controls during comparable periods using mixed-effect models.ResultsExcept for diabetes, there were substantial increases in healthcare visit rates in the last few months before a diagnosis of cancer or immune conditions, suggesting that some children had been seeking medical help and it had taken months to achieve a diagnosis. Many recorded presentations during this time were consistent with typical manifestations of the underlying condition, such as increasing apparent injuries before the diagnosis of bone cancer (6.6-fold increase in the most recent 4 months, 95% CI 4.9 to 9.0). Comparatively, healthcare visits in the year before the diagnosis of diabetes were less common, but at the time of diagnosis 64% (1504/2335) of children presented with diabetes ketoacidosis.ConclusionsMany children with cancer or immune diseases, even with typical presentations, required a period of time for the diagnosis to be confirmed. By contrast, children with type 1 diabetes typically did not visit a doctor until ketoacidosis had occurred.

Background Herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) are common human pathogens and might cause severe illness. Following primary infection, the viruses establish lifelong latent infection and are transmitted by close contact, both sexual and nonsexual. However, the information about the seroprevalence of HSV-1 and HSV-2 across all age groups is limited. Methods Residual sera collected during the nationwide serosurvey in 2007 in Taiwan were selected for the study. The enzyme-linked immunosorbent assay was used to detect anti-HSV-1 and anti-HSV-2 type-specific glycoprotein IgG. Demographics and personal health data were used for risk analysis. Results A total of 1411 and 1072 serum samples were included for anti-HSV-1 and anti-HSV-2 seroprevalence analysis, respectively. The weighted overall seroprevalence was 63.2% for HSV-1, and 7.7% for HSV-2, respectively. The HSV-1 seropositive rate was 19.2% for those less than 5 years old, increased to 46.4% for those aged 5-13 years, 60.9% for those aged 14-29 years, and reached as much as 95.0% for those aged over 30 years. In contrast, the HSV-2 seropositve rate was 1.6% for those less than 30 years old, rose to 10.1% for those age 30-39 years, and was up to 31.2% for those aged over 60 years. A significantly higher HSV-2 seropositive rate was noted in females than males aged over 40 years (26.3% v.s. 16.8%), and the overall HSV-2 seropositive rate was almost twice higher in females than males. Smoking history, drinking habit, and educational level were associated with the HSV-1 seropositivity. Female gender and rural residence were independent factors for the HSV-2 seropositivity. Conclusions An obvious increase of primary HSV-1 infection occurred in late adolescents and young adults, joined by the rise of HSV-2 infection in middle-aged adults, especially females. The acquistion and transmission of HSV warrant further studies in the susceptible population.