Virus Antibody Levels Research Articles

Study on Varicella-Zoster Virus Antibody Levels among Children Aged 1-7 Years in Changzhou, China.

We aim to understand the varicella-zoster virus (VZV) antibody levels in children after vaccination and to construct VZV-IgG centile curves and reference values for children aged 1-7 years. From September to October 2023, a total of 806 children were recruited according to the time intervals of 1 month, 6 months, 1 year, 2 years, and 3 years after vaccination, as well as age groups. A generalized additive model for location, shape, and scale (GAMLSS) was applied to estimate P3, P10, P25, P50, P75, P90, and P97 centile reference values of VZV-IgG, and 95% reference intervals were calculated. A total of 785 children were included in the analysis, with an overall positivity rate of 70.3%, a median antibody concentration of 192.05 (82.89-571.14) mIU/mL, and a positivity rate of 57.7% for one dose of vaccine and 84.2% for two doses. Antibody positivity rates at 1 month, 6 months, 1 year, 2 years, and 3 years after vaccination were 65.1%, 74.4%, 80.4%, 67.7%, and 63.0%, respectively. The GAMLSS results showed that VZV-IgG had a tendency to increase and then decrease after vaccination, and the second dose of vaccination could significantly increase VZV-IgG. Two doses of varicella vaccine should be administered to children in a timely manner and included in the routine vaccination programs.

Effect of anti-Ebola virus monoclonal antibodies on endogenous antibody production in survivors of Ebola virus disease in the Democratic Republic of the Congo: an observational cohort study

The use of specific anti-Ebola virus therapy, especially monoclonal antibodies, has improved survival in patients with Ebola virus disease. We aimed to assess the effect of monoclonal antibodies on anti-Ebola virus antibody responses in survivors of the 2018-20 Ebola outbreak in the Democratic Republic of the Congo. In this observational prospective cohort study, participants were enrolled at three Ebola survivor clinics in Beni, Mangina, and Butembo (Democratic Republic of the Congo). Eligible children and adults notified as survivors of Ebola virus disease (ie, who had confirmed Ebola virus disease [RT-PCR positive in blood sample] and were subsequently declared recovered from the virus [RT-PCR negative in blood sample] with a certificate of recovery from Ebola virus disease issued by an Ebola treatment centre) during the 2018-20 Ebola virus disease outbreak were invited to participate in the study. Participants were recruited on discharge from Ebola treatment centres and followed up for 12-18 months depending on recruitment date. Routine follow-up assessments were done at 1, 3, 6, and 12-18 months after inclusion. We collected sociodemographic (age, sex, visit site), clinical (anti-Ebola virus drugs), and laboratory data (RT-PCR and Ct values). The primary outcome was the antibody concentrations against Ebola virus glycoprotein, nucleoprotein, and 40-kDa viral protein antigens over time assessed in all participants. Antibody concentrations were measured by the multiplex immunoassay, and the association between anti-Ebola virus antibody levels and the relevant exposures, such as anti-Ebola virus disease drugs (ansuvimab, REGN-EB3, ZMapp, or remdesivir), was assessed using both linear and logistic mixed regression models. This study is registered at ClinicalTrials.gov, NCT04409405. Between April 16, 2020, and Oct 18, 2021, 1168 survivors were invited to participate in the Les Vainqueurs d'Ebola cohort study. 787 survivors were included in the study, of whom 358 had data available for antibody responses. 85 (24%) of 358 were seronegative for at least two Ebola virus antigens on discharge from the Ebola treatment centre. The antibody response over time fluctuated but a continuous decrease in an overall linear evolution was observed. Quantitative modelling showed a decrease in nucleoprotein, glycoprotein, and VP-40 antibody concentrations over time (p<0·0001) with the fastest decrease observed for glycoprotein. The probability of being seropositive for at least two antigens after 36 months was 53·6% (95% CI 51·6-55·6) for participants who received ansuvimab, 73·5% (71·5-75·5) for participants who received REGN-EB3, 76·8% (74·8-78·8) for participants who received remdesivir, and 78·5% (76·5-80·5) for participants who received ZMapp. Almost a quarter of survivors were seronegative on discharge from the Ebola treatment centre and antibody concentrations decreased rapidly over time. These results indicate that monoclonal antibodies might negatively affect the production of anti-Ebola virus antibodies in survivors of Ebola virus disease which could increase the risk of reinfection or reactivation. The French National Agency for AIDS Research-Emergent Infectious Diseases-The French National Institute of Health and Medical Research, the French National Research Institute for Development, and the European and Developing Countries Clinical Trials Partnership. For the French translation of the abstract see Supplementary Materials section.

Immunomodulatory effect of Atractylodis macrocephala Koidz. polysaccharides in vitro

Vaccination is still the main method of preventing most infectious diseases, but there are inefficiencies and inaccuracies in immunization. Studies have reported that Atractylodis macrocephalae Koidz. polysaccharides (RAMP) have immunomodulatory effects, but the mechanisms involved in whether they can modulate the immune response in chickens are not yet clear. The aim of this study was to investigate the effect of RAMP on lymphocytes functions by analyzing cell proliferation, cell cycle, mRNA expression of cytokines and CD4 +/CD8+ratio. To identify potential molecules involved in immune regulation, we performed a comprehensive transcriptome profiling of chicken lymphocytes. In addition, the adjuvant effect of RAMP was evaluated by detecting indicators of hemagglutination inhibition. When lymphocytes were cultured with RAMP in vitro, the proliferation rate of lymphocytes was increased (P < 0.01), more cells in S phase and G2/M phase (P < 0.01) and the mRNA expression of IFN-γ was upregulated (P < 0.05), while the mRNA expression of TGF-β (P < 0.01) and IL-4 (P < 0.05) was downregulated and the CD4 +/CD8+ratio was increased (P < 0.05). Transcriptomic results showed that RAMP increased the expression of HIST1H46 (P < 0.05) and CENPP (P < 0.05). Validation of qPCR showed that RAMP may play an important role in regulating cellular immunity by downregulating the Notch pathway. The results also showed that RAMP could increase the serum Newcastle disease virus antibody levels in chickens. These data suggest that RAMP could enhance immune function of lymphocytes and was a candidate vaccine adjuvant in chickens.

Bovine Viral Diarrhea Virus Antibody Level Variation in Newborn Calves after Vaccination of Late-Gestational Cows.

This study was conducted to confirm variation in bovine viral diarrhea virus (BVDV) antibody levels transferred to calves from their mother's colostrum after vaccination of late-gestational cows. Blood samples were drawn from 60 pregnant cows that had been vaccinated more than one year and less than two years previously. The samples were collected six weeks prior to the expected date of delivery. After sample collection, the cows were divided into two groups of 30. One group received 2 mL of BVDV vaccine, and a control group received 2 mL of phosphate-buffered saline (PBS). Blood was collected from the cows three weeks post-administration. Additional blood samples were taken from calves at 1, 4, 8, 12, 16, and 20 weeks after birth. The serum was separated from the collected blood, and BVDV antibody changes were confirmed by enzyme-linked immunosorbent assays. BVDV antibody levels were higher from 8 to 20 weeks of age in calves born to late-gestational BVDV-vaccinated cows than in calves born to control cows (p < 0.0083). Further analysis confirmed a slow decline in BVDV maternal antibodies in calves born to pregnant cows that produced high levels of BVDV antibodies following pre-calving BVDV vaccination. These results suggest that BVDV vaccination of cattle in late pregnancy may help to extend the duration of protection against BVDV infection in newborn calves.

Safety and immunogenicity of a single-shot live-attenuated chikungunya vaccine: a double-blind, multicentre, randomised, placebo-controlled, phase 3 trial

VLA1553 is a live-attenuated vaccine candidate for active immunisation and prevention of disease caused by chikungunya virus. We report safety and immunogenicity data up to day 180 after vaccination with VLA1553. This double-blind, multicentre, randomised, phase 3 trial was done in 43 professional vaccine trial sites in the USA. Eligible participants were healthy volunteers aged 18 years and older. Patients were excluded if they had history of chikungunya virus infection or immune-mediated or chronic arthritis or arthralgia, known or suspected defect of the immune system, any inactivated vaccine received within 2 weeks before vaccination with VLA1553, or any live vaccine received within 4 weeks before vaccination with VLA1553. Participants were randomised (3:1) to receive VLA1553 or placebo. The primary endpoint was the proportion of baseline negative participants with a seroprotective chikungunya virus antibody level defined as 50% plaque reduction in a micro plaque reduction neutralisation test (μPRNT) with a μPRNT50 titre of at least 150, 28 days after vaccination. The safety analysis included all individuals who received vaccination. Immunogenicity analyses were done in a subset of participants at 12 pre-selected study sites. These participants were required to have no major protocol deviations to be included in the per-protocol population for immunogenicity analyses. This trial is registered at ClinicalTrials.gov, NCT04546724. Between Sept 17, 2020 and April 10, 2021, 6100 people were screened for eligibility. 1972 people were excluded and 4128 participants were enrolled and randomised (3093 to VLA1553 and 1035 to placebo). 358 participants in the VLA1553 group and 133 participants in the placebo group discontinued before trial end. The per-protocol population for immunogenicity analysis comprised 362 participants (266 in the VLA1553 group and 96 in the placebo group). After a single vaccination, VLA1553 induced seroprotective chikungunya virus neutralising antibody levels in 263 (98·9%) of 266 participants in the VLA1553 group (95% CI 96·7-99·8; p<0·0001) 28 days post-vaccination, independent of age. VLA1553 was generally safe with an adverse event profile similar to other licensed vaccines and equally well tolerated in younger and older adults. Serious adverse events were reported in 46 (1·5%) of 3082 participants exposed to VLA1553 and eight (0·8%) of 1033 participants in the placebo arm. Only two serious adverse events were considered related to VLA1553 treatment (one mild myalgia and one syndrome of inappropriate antidiuretic hormone secretion). Both participants recovered fully. The strong immune response and the generation of seroprotective titres in almost all vaccinated participants suggests that VLA1553 is an excellent candidate for the prevention of disease caused by chikungunya virus. Valneva, Coalition for Epidemic Preparedness Innovation, and EU Horizon 2020.

Association of fat-soluble vitamins (A, D, and E) status with humoral immune response to COVID-19 inactivated vaccination.

Fat-soluble vitamins (A, D, and E) are essential for the proper functioning of the immune system and are of central importance for infection risk in humans. Vitamins A, D, and E have been reported to be associated with the immune response following vaccination; however, their effects on the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination remain unknown. We measured the neutralizing antibody titers against wild type and omicron within 98 days after the third homologous boosting shot of inactivated SARS-CoV-2 vaccine (BBIBP-CorV or CoronaVac) in 141 healthy adults in a prospective, open-label study. High-performance liquid chromatography-tandem mass spectroscopy was used to determine the concentrations of plasma vitamins A, D, and E. We found that the anti-wide-type virus and anti-omicron variant antibody levels significantly increased compared with baseline antibody levels (P < 0.001) after the third vaccination. 25(OH)D3 was significantly negatively associated with the baseline anti-wide-type virus antibody concentrations [beta (95% CI) = -0.331 (-0.659 ~ -0.003)] after adjusting for covariates. A potentially similar association was also observed on day 98 after the third vaccination [beta (95% CI) = -0.317 (-0.641 ~ 0.007)]. After adjusting for covariates, we also found that 25(OH)D3 was significantly negatively associated with the seropositivity of the anti-omicron variant antibody at day 98 after the third vaccination [OR (95% CI) = 0.940 (0.883 ~ 0.996)]. The association between plasma 25(OH)D3 with anti-wild-type virus antibody levels and seropositivity of anti-omicron variant antibodies were persistent in subgroup analyses. We observed no association between retinol/α-tocopherol and anti-wide-type virus antibody levels or anti-omicron variant antibody seropositive in our study. The third inactivated SARS-CoV-2 vaccination significantly improved the ability of anti-SARS-CoV-2 infection in the human body. Higher vitamin D concentrations could significantly decrease the anti-wide-type virus-neutralizing antibody titers and anti-omicron variant antibody seropositive rate after the inactivated SARS-CoV-2 vaccination in people with adequate levels of vitamin D, better immune status, and stronger immune response; further studies comprising large cohorts of patients with different nutritional status are warranted to verify our results.

Comparison of Immune-Related Gene Expression in Two Chicken Breeds Following Infectious Bronchitis Virus Vaccination.

This study aims to identify the immune-related genes and the corresponding biological pathways following infectious bronchitis virus vaccination in Taiwan Country and White Leghorn chicken breeds. Transcriptomic analyses of the spleen of these two breeds were conducted by next-generation sequencing. Compared to White Leghorn chicken, Taiwan Country chicken showed a significantly higher level of anti-infectious bronchitis virus (IBV) antibodies at 14 and 21 days pos vaccination. At 7 days post vaccination, in the Taiwan Country chicken, higher expression of mitogen-activated protein kinase 10, Major histocompatibility complex class 1, and V-set pre-B cell surrogate light chain 3 were found. In contrast, the White Leghorn chicken had a high expression of interleukin 4 induced 1, interleukin 6, and interleukin 22 receptor subunit alpha 2. These findings have highlighted the variations in immune induction between chickens with distinct genetic background and provided biological pathways and specific genes involved in immune responses against live attenuated IBV vaccine.

The diagnostic significance of hepatitis C virus antibody levels for chronic hepatitis C virus infection.

Although anti-hepatitis C virus (HCV) assay is widely used to screen for HCV infection, it has a high false-positive (FP) rate in low-risk populations. We investigated the accuracy of anti-HCV signal-to-cutoff (S/CO) ratio to distinguish true-positive (TP) from FP HCV infection. We retrospectively analyzed 77,571 patients with anti-HCV results. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic accuracy of anti-HCV S/CO ratio in anti-HCV positive patients. Overall, 1,126 patients tested anti-HCV positive; 34.7% of patients were FP based on HCV RNA and/or recombinant immunoblot assay (RIBA) results. The age and sex-adjusted anti-HCV prevalence was 1.22%. We identified significant differences in serum aspartate transaminase and alanine transaminase levels, anti-HCV S/CO ratio, and RIBA results between groups (viremia vs. non-viremia, TP vs. FP). Using ROC curves, the optimal cutoff values of anti-HCV S/CO ratio for HCV viremia and TP were 8 and 5, respectively. The area under the ROC curve, sensitivity, specificity, positive and negative predictive values were 0.970 (95% CI, 0.959-0.982, p < 0.001), 99.7%, 87.5%, 87.4%, and 99.7%, respectively, for predicting HCV viremia at an anti-HCV S/CO ratio of 8 and 0.987 (95% CI, 0.980-0.994, p < 0.001), 95.3%, 94.7%, 97.1%, and 91.4%, respectively, for TP HCV infection at an anti-HCV S/CO ratio of 5. No patients with HCV viremia had an anti-HCV S/CO ratio below 5. The anti-HCV S/CO ratio is highly accurate for discriminating TP from FP HCV infection and should be considered when diagnosing HCV infections.

Hepatitis B virus vaccination post serological testing and antibody levels of vaccinated health care workers in Accra, Ghana

IntroductionHepatitis B Virus (HBV) infection is an important occupational hazard to Health Care Workers (HCWs) all over the world. International health organizations have strongly recommended the use of the HBV vaccine, especially among individuals at risk of HBV infection. A laboratory test aimed at measuring Anti-HBs concentration (titer) 1–2 months following a 3-dose vaccination schedule is the most reliable approach for diagnosing seroprotection against HBV. This study sought to assess post-vaccination serological testing, seroprotection against HBV, and associated factors among vaccinated HCWs in Ghana. MethodsA hospital-based analytical cross-sectional study involving 207 HCWs. Pretested questionnaires were used to collect data. 5mls of venous blood were collected from consenting HCWs under strict aseptic conditions and quantitatively analyzed for Anti-HBs using ELISA procedures. SPSS Version 23 was used to analyze data with the level of significance set at 0.05. ResultsMedian age; 33, IQR of 29–39. The post-vaccination serological testing rate was 21.3 %. HCWs with high-risk perception and working at the regional hospital had lower odds of adherence to post-vaccination serological testing (aOR = 0.2; 95 % CI = 0.1–0.7) and (aOR = 0.1; 95 % CI = 0.1–0.6) p < 0.05. The seroprotection rate was 91.3 % (95 % CI = 87 %-95 %). Minority, 18 (8.7 %) of the 207 vaccinated HCWs had antibody titers below 10mIU/mL and were not seroprotected against HBV. Geometric Mean Titers (GMTs) were higher in those who received three doses, took a booster, and were less than 25 kg/m2. ConclusionThe post-vaccination serological testing practice was sub-optimal. The seroprotection rate was higher with higher GMTs in those who adhered to the 3-dose vaccination regimen, took a booster dose, and had BMI < 25 kg/m2. It may be inferred that those with Anti-HBs below 10 IU/ml had their antibodies diminishing or waning off with time or they are true vaccine non-responders. This observation calls for strict adherence to post-vaccination serological testing, especially for HCWs who are at high risk of percutaneous and mucocutaneous exposures that could result in HBV infection.

Factors Associated with Dog Rabies Immunization in Changsha, China: Results of a Cross-Sectional Cluster Survey, 2015-2021.

The objective of this study was to examine longitudinal trends in the prevalence of dogs that are successfully immunized against rabies virus (as measured by sufficient serum antibodies) in Changsha, an urban center of China. The secondary objective was to investigate the factors affecting the seroprevalence of rabies virus antibodies in dogs. In this study, 4515 canine serum samples were collected from 57 pet hospitals (immunization points) during the period of 2015-2021 in five major urban areas of Kaifu, Furong, Tianxin, Yuhua, and Yuelu in Changsha, China. The enzyme-linked immunosorbent assay (ELISA) method was used to analyze the level and trend of rabies virus antibodies in serum and further evaluate the potential factors affecting the immunization effect from five factors: sex, age, time interval after most recent vaccination and sample collection, number of vaccinations, and vaccine manufacturer. The results showed that the seroconversion from the urban dog in Changsha steadily increased from 46.13% to 73.38% during 2015-2017. The seropositivity prevalence remained above the international standard (70%) from 2018 to 2020 and up to 90.99% in 2021. Further analysis showed that the seroconversion of rabies virus among dogs was significantly affected by the age, the number of vaccinations, time interval after the most recent vaccination and sample collection, and vaccine manufacturer, while sex had less influence. The overall rabies vaccination situation in urban areas of Changsha generally meets international standards, with only a few areas showing low levels of antibodies in dogs after vaccination and risk of infectiousness. Therefore, it is recommended that the first vaccination should be given when the dog is about three months old and regularly repeated every year after that. At the same time, antibody concentrations in dogs, especially in newborn puppies and older dogs, need to be tested promptly after vaccination at the required time to ensure that they are at a high level of immune protection, which can strengthen the supervision of rabies.

Immune response of European sea bass (Dicentrarchus labrax L.) against combination of antigens from three different pathogens

Three of the most important diseases of Mediterranean intensive European sea bass farming are, viral nervous necrosis (VNN) caused by the red grouper nervous necrosis virus (RGNNV) genotype of b-nodavirus, photobacteriosis caused by Photobacterium damselae subsp. piscicida (Phdp) and vibriosis caused mainly by the O1 serotype of Vibrio anguillarum (VaO1). Prevention against these diseases is performed through vaccination with a monovalent vaccine against the viral disease and, usually, with bivalent vaccines against the bacterial diseases. However, it is very difficult to program two vaccinations during the same season for the same fish stock and producers are forced to either vaccinate for the viral or the bacterial diseases or to perform double vaccination with both vaccines, without any prior knowledge on any interactions that may occur due to the plethora of antigens (Ag) injected. Ideally, therefore, a trivalent vaccine should be developed against all three diseases. The objective of this work was to analyse the immune response of sea bass against combinations of Ags from all three pathogens, namely viral particles, Phdp whole cells (WC), lipopolysaccharide (LPS), capsular polysaccharide (CPS) and extracellular products (ECPs) and VaO1 WC and ECPs in respect to the identification of any phenomena of immunodominance/immunosuppression between Ags with a view to select candidate Ags for inclusion in a trivalent vaccine formulation. Eight triplicate groups of fish were immunized with different combinations of the aforementioned Ags and another triplicate group served as negative control. Blood serum was isolated at various time-points post-immunization for the measurement of specific antibodies against each Ag and, in addition, leucocytes were isolated at day 29 post-immunization for analysis of various cellular activities. Results indicated that best levels of specific a-NNV virus antibodies (Abs) were produced when VaO1 ECPs were not included in the Ag combinations, in contrast to the leucocytes proliferation assay where best stimulation against NNV Ags was measured when VaO1 ECPs were present in Ag combinations. VaO1 ECPs apparently is a strong immunogen for both humoral and cellular responses but suppresses immunological reactions against the other Ags.VaO1 WC, Phdp LPS and ECPs raised good humoral immune responses in the groups with best responses against VNN Ags, but only VaO1 WC and Phdp ECPs provided good stimulation of leucocytes, with Phdp WC and CPS effecting either similar stimulation with untrained leucocytes (control groups) or down-stimulation. Results are discussed with a view to select Ags from all three pathogens for inclusion in trivalent vaccine against all three pathogens.

Human immune globulin treatment controls Zika viremia in pregnant rhesus macaques.

There are currently no approved drugs to treat Zika virus (ZIKV) infection during pregnancy. Hyperimmune globulin products such as VARIZIG and WinRho are FDA-approved to treat conditions during pregnancy such as Varicella Zoster virus infection and Rh-incompatibility. We administered ZIKV-specific human immune globulin as a treatment in pregnant rhesus macaques one day after subcutaneous ZIKV infection. All animals controlled ZIKV viremia following the treatment and generated robust levels of anti-Zika virus antibodies in their blood. No adverse fetal or infant outcomes were identified in the treated animals, yet the placebo control treated animals also did not have signs related to congenital Zika syndrome (CZS). Human immune globulin may be a viable prophylaxis and treatment option for ZIKV infection during pregnancy, however, more studies are required to fully assess the impact of this treatment to prevent CZS.

Human immunodeficiency virus p24 antigen and antibody, herpes simplex virus-2 IgM and tumor necrosis factor alpha plasma levels in adult female children living in single-parent households: a case-control observational study

Abstract Objective: Human immunodeficiency virus (HIV) p24 antigen and antibody and herpes simplex virus 2 IgM are seromarkers indicating infection with HIV and herpes simplex virus-2 (HSV-2), respectively, whereas tumor necrosis factor α is an inflammatory biomarker that can be triggered by infections. Female children of single parents are faced with many socio-economic challenges that make them vulnerable to sexual influences and prone to sexually transmitted infections. The goal of this work was to determine HIV p24 antigen/antibody, HSV-2 IgM and tumor necrosis factor-α plasma levels in adult female children living in single-parent households. Methods: In this case-control observational study, 100 adult female children living with a single parent (50 living with a single mother and 50 living with a single father; age: 18–22 years) and 100 age-matched women living with both parents were recruited to serve as the test and control groups, respectively. All subjects were negative for acid-fast bacilli, plasmodium, hepatitis C virus, and hepatitis B virus. Human tumor necrosis factor α, HSV-2 IgM, antibody to hepatitis C virus, hepatitis B surface antigen and human immunodeficiency virus p24 antigen and antibody (HIV p24 Ag/Ab) levels were determined by ELISA, while the detection of acid-fast bacilli in sputum and Plasmodium in blood was carried out by optical microscopy. This work was carried out in the Owo/Ose Federal Constituency in Ondo State that shares boundaries with Edo State. The study protocol was approved by the Research and Ethical Committee of the Department of Medical Laboratory Science, Achievers University, Owo, Nigeria (AUO/MLS/2020/127) on August 27, 2020. Results: HIV p24 Ag/Ab was detected in 0 adult female children living with a single mother, 1 (2%) adult female child living with a single father and 1 (1%) adult female child living with both parents. HSV-2 IgM was detected in 9 (18%) adult female children living with a single mother, 13 (26%) adult female children living with a single father, and 5 (10%) adult female children living with both parents. Conclusion: This work shows that adult female children of single parents are vulnerable to sexual influences, and thereby more prone to HSV-2 and possibly HIV, especially adult female children of single fathers.

Prevalence and Genetic Analysis of Porcine Circovirus 3 in China From 2019 to 2020.

Porcine circovirus type 3 (PCV3), a virus belonging to the Circoviridae family, is considered to be associated with respiratory and neurological signs, cardiac and multisystemic inflammation, reproductive failure, and porcine dermatitis and nephropathy syndrome-like disease in pigs (Sus scrofa). In this study, epidemiological and serological investigations of PCV3 in clinically healthy pigs from different regions of China were performed. Overall, 42.87% (1,101/2,568) of pigs were positive for PCV3 Cap antibody via indirect enzyme-linked immunosorbent assay, with a higher prevalence of PCV3 in multiparous sows (62.22%, 881/1,416) and fattening pigs (28.96%, 159/549) than in suckling piglets (8.96%, 32/357) and nursery pigs (11.79%, 29/246). Of the 2,568 samples, 255 were further tested for PCV3 DNA using real-time polymerase chain reaction, and 63.14% of these were positive, with nearly half having <10 virus copies. The PCV3 DNA and antibody positivity rates were high in the pig serum samples; however, the virus titers and antibody levels were both low, indicating that the humoral immune response of PCV3-infected pigs was weak or lagging, and persistent or repeated infections could occur. Additionally, the complete genomes of 23 PCV3 strains were sequenced and analyzed, which showed nucleotide identities of 98.5~100.0%, 98.6~100.0%, and 99.2~100.0% in the complete genome, open reading frame (ORF)2, and ORF1 sequences, respectively, and amino acid identities of 96.7~100.0% and 99.3~100.0% in the capsid and replicase proteins, respectively. Phylogenetic analysis based on ORF2 nucleotide sequences indicated that the PCV3 strains obtained in the present study could be classified into three sub-clades, with most strains clustered into clade 3c, indicating that PCV3c is the dominant subtype in the regions of China investigated. In general, the present study revealed a high prevalence and high genetic divergence of PCV3 among Chinese pig herds, and indicated that the potential effect of PCV3 on the pig industry may be a concern.

Association Between Traditional Herbal Diet and Nasopharyngeal Carcinoma Risk: A Prospective Cohort Study in Southern China.

IntroductionProspective evidence for herbal diet and nasopharyngeal carcinoma (NPC) development is absent. We therefore evaluated the associations of herbal soup and herbal tea with NPC in a prospective cohort study in southern China.MethodsBased on an NPC screening cohort established in 2008–2015, information on herbal diet consumption, potential confounding factors, and Epstein-Barr virus (EBV) antibody levels were collected from 10,179 individuals aged 30–69 years in Sihui city, southern China. Cox regression models were performed to examine herbal diet with NPC risk, and logistic regression models were used to examine herbal diet with EBV reactivation.ResultsDuring a median of 7.54 years of follow-up, 69 participants developed NPC. Herbal soup consumption was associated with decreased NPC risk, with HRs of 0.31 (95% confidence interval (CI): 0.15–0.62) for the highest intake frequency and 0.29 (95% CI: 0.16–0.51) for a longer duration. However, herbal tea was not significantly associated. Moreover, we identified herbal soup was inversely associated with EBV seropositivity among all the participants at baseline, with the adjusted ORs being 0.78 (95% CI: 0.65–0.93) for immunoglobulin A antibodies against EBV capsid antigens (VCA-IgA) and 0.76 (95% CI: 0.64–0.91) for nuclear antigen 1 (EBNA1-IgA) in those with the highest frequency and 0.70 (95% CI: 0.59–0.84) for VCA-IgA and 0.64 (95% CI: 0.54–0.77) for EBNA1-IgA in those with the longer duration. Inverse associations were also observed in non-NPC individuals.ConclusionsWith inhibition of EBV reactivation by plants, herbal soup could significantly decrease the risk of NPC in endemic areas.

Low immunity against vaccine preventable diseases in Turkish HIV cohort

Background/aimHIV infection increase the risk of serious disease resulting from common vaccine-preventable infections. Vaccinations are particularly important for HIV infected adults. We aimed to investigate the immunity rates against measles, mumps, rubella, hepatitis A, B, and tetanus in newly diagnosed HIV patients. Materials and methodsPatients who admitted to outpatient clinics of three centers with newly diagnosed HIV infection, between 1 January 2015 and 31 June 2017 were included. Measles, mumps, rubella, varicella zoster virus, hepatitis A, hepatitis B, and tetanus antibody levels were measured by commercial diagnostic kits. Demographical and laboratory data of the patients were recorded.ResultsFive hundred and twenty-three patients were enrolled in the study. Of the patients 87% were male (n = 455) and the mean age was 38 ± 13 years. Serology was available for measles 74.2% (388/523), mumps 73.8% (386/523), rubella 77.8% (407/523), hepatitis A 88.5% (463/523), hepatitis B 97.7% (511/523), tetanus 8.6% (45/523), and VZV 79.9% (418/523). Seropositivity was 82% for measles, 75.6% for mumps, 92.1% for rubella. Of the patients whom all three of the components of the MMR vaccine was tested, 37.7% (127/337) were susceptible at least one and needed the vaccine. Mean age was lower in patients who are nonimmune to measles and mumps (p = 0.008). Younger patients were also nonimmune for hepatitis A, while older patients were nonimmune for hepatitis B.ConclusionIn our study we found that rates of nonimmunity can increase up to one third of the patients even though there is a national vaccination program. Nonimmune individuals should be detected and vaccinated in line with recent guidelines and response should be monitored because of the possibility of impaired immunity and possible suboptimal response. National campaigns can be launched for adult immunization and physicians should be aware of the importance of adult immunization.

A Meta-analysis on varicella-zoster virus antibody levels in healthy population in China

Objective: To systematically analyze and evaluate the IgG antibody levels of varicella-zoster virus (VZV) in healthy population in China. Methods: CNKI, Wanfang, CBM and PubMed databases were used for the retrieval of literatures about VZV IgG antibody levels in healthy people in China from January 1, 2000 to November 3, 2020. The quality of the included papers was evaluated by the critical appraisal tools for cross sectional study from Joanna Briggs Institute (JBL). The stratified analysis on the IgG antibody levels in populations in different age groups, provinces, regions, gender groups, and years was performed by using software Stata 14.0. Results: A total of 59 papers were included that met the inclusion criteria, including 51 papers in Chinese and 8 papers in English. There were 22 papers with quality score of 8, 16 papers with quality score of 7, 15 papers with quality score of 6, and 6 papers with quality score of 5. Meta-analysis showed that the positive rate of VZV IgG antibody in healthy population in China was 64% (95%CI:60%-67%, I2 =98.7%), and the IgG antibody levels were reported in the papers for 22 provinces of China. The positive rate of VZV IgG antibody was highest in Yunnan (79%, 95%CI: 64%-93%, I2 =94.7%) and lowest in Inner Mongolia (50%, 95%CI: 46%-54%); the positive rate of VZV IgG antibody was highest in Northeastern China (71%, 95%CI: 69%-73%) and lowest in Eastern China (62%, 95%CI: 57%-67%); the positive rate of VZV IgG antibody in urban population was higher than that in rural population (RR=1.08, 95%CI: 1.04-1.11). The positive rate of VZV IgG antibody in women was higher than that in men (RR=1.10, 95%CI: 1.08-1.11); the positive rate of VZV IgG antibody in the population increased with age; and the positive rate of VZV IgG antibody increased with the change of sampling time. Conclusion: The positive rate of VZV IgG antibody in healthy population in China was relatively low; the coverage of varicella vaccine should be improved for the outbreak control and incidence reduction of varicella in China.

The Effect of the Antimicrobial Peptide Plectasin on the Growth Performance, Intestinal Health, and Immune Function of Yellow-Feathered Chickens.

The goal of the study was to test the effects of an antibiotic substitute, plectasin, on the growth performance, immune function, intestinal morphology and structure, intestinal microflora, ileal mucosal layer construction and tight junctions, ileal immune-related cytokines, and blood biochemical indices of yellow-feathered chickens. A total of 1,500 one-day-old yellow-feathered chicks were randomly divided into four dietary treatment groups with five replicates in each group and 75 yellow-feathered chicks in each replication, as follows: basal diet (group A); basal diet supplemented with 10 mg enramycin/kg of diet (group B), basal diet supplemented with 100 mg plectasin/kg of diet (group C), and basal diet supplemented with 200 mg plectasin/kg of diet (group D). It was found that the dietary antimicrobial peptide plectasin could improve the ADG and had better F/G for the overall period of 1–63 days. Dietary plectasin can enhance H9N2 avian influenza virus (AIV) and Newcastle disease virus (NDV) antibody levels of yellow-feathered chickens at 21, and 35 days of age. Dietary plectasin can enhance the intestine structure, inhibit Escherichia coli and proinflammatory cytokines in the ileum, and ameliorate the blood biochemical indices of yellow-feathered chickens at 21 days of age. This study indicates that the antimicrobial peptide plectasin has beneficial effects on the growth performance, intestinal health and immune function of yellow-feathered chickens.

Porcine reproductive and respiratory syndrome virus (PRRSV) antibody levels in large swine farms in selected regions of Yunnan province, China

Porcine reproductive and respiratory syndrome (PRRS) is caused by the PRRS virus (PRRSV), and it is a widespread disease that severely affects swine production in all age groups. Detection of PRRSV antibody levels in pig farms is beneficial for immunity evaluations. In this study, a total of 1,206 serum samples of breeding boars, breeding sows, reserve pigs and commercial pigs from 16 large-scale swine farms in 4 different regions of Yunnan province in China were collected during 2019 and detected by indirect enzyme-linked immunosorbent assay (ELISA). The results showed that the average positive rate of PRRSV antibody was 88.32%, among which the antibody-positive rates were 89.03%, 89.18%, 92.11%, and 82.95% in East Yunnan (E. Yunnan), Central Yunnan (Cent. Yunnan), Northwest Yunnan (N.W. Yunnan) and Northeast Yunnan (N.E. Yunnan), respectively (P &gt; 0.05). For the different pig categories, the reserve pigs (93.51%) showed much higher antibody-positive rates, followed by breeding sows (92.44%), commercial pigs (87.34%) and breeding boars (85.62%). Statistical analysis revealed that the rates were significantly different among different pig categories (P &lt;0.05). These s results indicated that pig categories were significantly associated with PRRSV antibody levels in this study. All the positive rates in this study fulfilled the requirement of ≥ 70% set by the National Animal Disease Surveillance Plan of China (2011). The study could provide evidence of the antibody response of PRRSV at the farm level.

New Algorithms Improving PML Risk Stratification in MS Patients Treated With Natalizumab.

Overview: We assessed the role of age and disease activity as new factors contributing to establish the risk of progressive multifocal leucoencephalopathy in multiple sclerosis patients treated with natalizumab in 36 University Hospitals in Europe. We performed the study in 1,307 multiple sclerosis patients (70.8% anti-John Cunninghan virus positive antibodies) treated with natalizumab for a median time of 3.28 years. Epidemiological, clinical, and laboratory variables were collected. Lipid-specific IgM oligoclonal band status was available in 277 patients. Factors associated with progressive multifocal leucoencephalopathy onset were explored by uni- and multivariate logistic regression.Results: Thirty-five patients developed progressive multifocal leucoencephalopathy. The multivariate analysis identified anti-John Cunninghan virus antibody indices and relapse rate as the best predictors for the onset of this serious opportunistic infection in the whole cohort. They allowed to stratify progressive multifocal leucoencephalopathy risk before natalizumab initiation in individual patients [area under the curve (AUC) = 0.85]. The risk ranged from <1/3,300 in patients with anti-John Cunninghan virus antibody indices <0.9 and relapse rate >0.5, to 1/50 in the opposite case. In patients with lipid-specific IgM oligoclonal bands assessment, age at natalizumab onset, anti-John Cunninghan virus antibody indices, and lipid-specific IgM oligoclonal band status predicted progressive multifocal leucoencephalopathy risk (AUC = 0.92). The absence of lipid-specific IgM oligoclonal bands was the best individual predictor (OR = 40.94). The individual risk ranged from <1/10,000 in patients younger than 45 years at natalizumab initiation, who showed anti John Cunningham virus antibody indices <0.9 and lipid-specific IgM oligoclonal bands to 1/33 in the opposite case.Conclusions: In a perspective of personalized medicine, disease activity, anti-lipid specific IgM oligoclonal bands, anti Jonh Cunninghan virus antibody levels, and age can help tailor natalizumab therapy in multiple sclerosis patients, as predictors of progressive multifocal leucoencephalopathy.