B Viruses Research Articles

Characterization of antibodies in human immunoglobulin products from different regions worldwide

AimThe antibody levels against a broad spectrum of pathogens were assessed in commercial intravenous immunoglobulin (IVIG) manufactured from pooled plasma obtained from different global regions. MethodsTwenty-four IVIG commercial lots from eight manufacturers corresponding to 12 brands were analyzed. The plasma was collected in 10 countries/regions. Depending on each pathogen, antibody levels were measured using specific commercial IgG-specific enzyme immunoassay kits or by cell culture neutralization test and guinea pig skin neutralization test. A principal component analysis was performed. ResultsFor polio and diphtheria (reference markers of the US authorities), all IVIGs had relevant titers in accordance with reference levels. IVIGs from Canada, Australia, and the USA were positive for titers against globally distributed pathogens or those under vaccination programs in the developed world (parainfluenza, Epstein–Barr, varicella-zoster, influenza B, parvovirus B19, and measles viruses). IVIG from Taiwan and Hong Kong showed low antibody titers for these pathogens but high titers for Pseudomonas aeruginosa. IVIG from India had high titers for pathogens frequently found in developing countries (West Nile, dengue, chikungunya, and hepatitis E viruses and Streptococcus pneumoniae). IVIGs from Argentina, Spain, Israel, and Czechia showed intermediate antibody concentrations. ConclusionThe antibody profile in IVIG was greatly influenced by regional characteristics including climate, vaccination programs, and the prevalence of pathogens in the different countries and regions.

A longitudinal cohort study of enterovirus A71 infections in young children in Taiwan

Background: Enterovirus A71 (EV-A71) is causing cyclical epidemics of fatal hand-foot-mouth disease (HFMD) in Taiwan and other Asian countries. Evidence of its incidence rates and risk factors based on longitudinal cohort studies is scarce. This study aims to investigate age-specific and cumulative incidence rates and risk factors of EV71 infections from 2006 to 2012 in northern Taiwan. Methods and materials: A total of 759 neonates born between 2006 and 2009 were recruited. Participants’ sera were collected at their 6, 12, 24, 36, 48, 60, and 72 months of age to conduct serum neutralization test. In addition, throat swabs of the participants who presented symptoms of HFMD or herpangina were collected for virus isolation and molecular tests to detect EV71 infections. Asymptomatic primary infections and reinfections were identified based on >= 4-fold rise of serum neutralizing antibody titers in consecutive sera. We calculated age-specific and cumulative incidence rates, and fitted a Cox proportional hazards model to identify risk factors of EV71 infections. Results: Among the 576 participants being followed, 127 persons (22.0%) were confirmed as with EV71 infections (70 symptomatic, 57 asymptomatic cases). Of the 127 cases, 22 (17.3%) occurred their second (n = 20) or third (n = 2) reinfections (all asymptomatic) after the primary infection. Phylogenetic analysis revealed that two distinguishable genotype B5 viruses were introduced from southern Asia to cause large-scale epidemics in Taiwan in 2008 and 2012, respectively. Age-specific incidence increased from 2.03 per 100 person-years during 0–6 months of age to 19.33 during 49–60 months of age, and reduced to 9.57 during 61–72 months of age. The cumulative incidence till 72 months of age was 31.78%. A higher number of co-residing children under 5 years old was associated with higher risk of EV71 infections (hazard ratio = 1.28, 95% CI: 1.03–1.59). Conclusion: Our results indicated incidence rates increased with age and peaked at 5 years-old, cumulative incidence rate was nearly 32% by 6 years of age, and higher number of co-residing young children was associated with higher risk of EV71 infections. This longitudinal cohort study contributes to precisely estimate incidence rates of EV71 infections via a long-term follow-up, and provides insights into clinical trial designs of EV71 vaccines.

Anti-viral activity of enisamium iodide against viruses of influenza and ARVI's on different cell lines

Characterization of the antiviral properties of enisamium iodide against human respiratory viruses in in vitro experiments. In the course of experiments, the cytotoxic properties of enisamium iodide were studied against the cell lines Vero, MA-104, A549, L-41 and HEp-2. The antiviral activity of enisamium iodide was studied using virus yield reduction assay against influenza viruses, parainfluenza virus, respiratory syncytial virus, Coxsackie B3 and Coxsackie B4 viruses, as well as adenoviruses types 5 and 6. The most sensitive to the action of enisamium iodide was the human parainfluenza virus, whose activity decreased by 2.3 orders of magnitude under the action of the drug in A549 cells. Of the cell cultures used, enisamium iodide exhibited the maximum antiviral effect in human lung carcinoma cells A549, where, in its presence, the level of reproduction of adenoviruses of types 5 and 6, Coxsackie viruses B3 and B4, and human parainfluenza virus decreased by an order of magnitude or more. The antiviral activity of enisamium iodide was least manifested in Vero cells. According to the results of in vitro experiments, enisamium iodide can be considered as an antiviral drug with a wide spectrum of activity against human respiratory viruses.

New multicomponent approach to polyfluoroalkylated pyrido[1,2-a]pyrimidine derivatives and bis-cyclohexenones

A one-pot three-component reactions between polyfluoroalkylated 3-oxo esters and methyl ketones with 1,3-diaminopropane result in 8-hydroxy-9a-alkyl(phenyl)-8-(polyfluoroalkyl)octahydro-6H-pyrido[1,2-a]pyrimidin-6-ones, whereas a similar reaction with 1,4-diaminobutane forms a salt with trifluoroacetoacetic ester. In a two-component reaction, diamines with a long aliphatic chain (1,4-diaminobutane, 1,6-diaminohexane and 1,8-diaminooctane) react with an aldol derived from trifluoroacetoacetic ester and acetone, to give bis-cyclohexenones having an aliphatic linker. Using 2-(aminomethyl)aniline in a three-component reaction with polyfluoroalkyl-3-oxo esters leads to new 7-hydroxy-5a-alkyl(phenyl)-7-(polyfluoroalkyl)-5a,6,7,8-tetrahydro-5H-pyrido[2,1-b]quinazolin-9(11H)-ones. Regioisomeric and spatial structures of new heterocycles were studied, and the mechanism of their formation was proposed. Some synthesized heterocycles were found to have moderate antiviral activity against influenza A/Puerto Rico/8/34 (H1N1) and Coxsackie B3 viruses.

Novel Antiviral and Antibacterial Activities of Hibiscus schizopetalus.

Hibiscus schizopetalus (Dyer) Hook.f. (Malvaceae) is an ornamental plant. The aim was to investigate its antimicrobial and antioxidant activities. In vitro antiviral, antibacterial, and antioxidant activities of the 70% ethanolic extract (Et-E) of the aerial parts of the plant were determined. The Dichloromethane Fraction (DCM-F) and the n-Butanol Fraction (Bu-F) were assessed using Liquid chromatography–mass spectrometry (LC-MS). The DCM-F showed higher antiviral activities against Coxsackie B4 (CoxB4) viruses (IC50 = 64.13 µg/mL) and adenoviruses (IC50 = 54.88 µg/mL) than acyclovir (IC50 = 72.79 µg/mL for CoxB4 viruses; IC50 = 91.92 µg/mL for adenoviruses). The DCM-F showed higher anti-helicobacter pylori activity (MIC = 3.9 µg/mL) than clarithromycin (MIC = 1.95 µg/mL). The DCM-F inhibited Herpes Simplex Virus (HSV) Type I (IC50 = 29.85 µg/mL) and HSV Type II (IC50 = 74.17 µg/mL). The Bu-F showed higher anti-mycobacterial activity (MIC = 7.81 µg/mL) than isoniazid (MIC = 0.24 µg/mL) and higher antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA)(MIC = 7.81 µg/mL) than vancomycin (MIC = 3.9 µg/mL). Antioxidant assays included total antioxidant capacity (TAC), 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picryl-hydrazyl (DPPH), and iron reducing power. The Bu-F showed the highest antioxidant activity. Chemical profiles were analyzed using HPLC-HR–ESI–MS to identify the metabolites responsible for these biological activities. We identified more than 60 metabolites that belong to anthocyanins, flavonoids, phenolics, terpenes, sterols, and fatty acids. In conclusion, Hibiscus schizopetalus is endowed with metabolites that could be used against viruses and antibiotic-resistant bacteria. They can also be potent antioxidants.

7-Imidazolyl-substituted 4'-methoxy and 3',4'-dimethoxy-containing polyfluoroflavones as promising antiviral agents

A simple and convenient method for the synthesis of new methyl 2-(4-methoxyphenyl)- and 2-(3,4-dimethoxyphenyl)-4-oxo-4H-polyfluorochromen-3-carboxylates as analogs of natural methoxy-containing flavones is proposed. As a result of their directed modification under basic conditions, 7-imidazolyl-substituted derivatives were obtained. In aqueous-organic medium under basic conditions, 5,6,7,8-tetrafluoro-3-(methoxycarbonyl)flavones were transformed into 6,8-difluoro-5-hydroxy-7-(1H-imidazol-1-yl)-3-(methoxycarbonyl)flavones as a result of flavone-5-hydroxyflavone rearrangement, while 6,7,8-trifluorinated analogs underwent a flavone-coumarin rearrangement to give 6,8-difluoro-3-(hydroxyarylidene)-7-(1H-imidazol-1-yl)coumarins under the same conditions. Acid hydrolysis of methyl polyfluoroflavone-3-carboxylates allowed to obtain 2-aryl-4H-polyfluorochromen-4-ones. Evaluation of the antiviral activity of the synthesized compounds against influenza A (H1N1) and Coxsackie B3 viruses showed that 2-(3,4-dimethoxyphenyl)-5,6,8-trifluoro-7-(1H-imidazol-1-yl)-4H-chromene-4-one has the most promising properties.

Emergence of genotype C1 Enterovirus A71 and its link with antigenic variation of virus in Taiwan.

An outbreak of the hand-foot-mouth disease with severe neurological cases, mainly caused by the genotype C1 enterovirus A71 (EV-A71), occurred in Taiwan between 2018 and early 2019. In the recent decade, the most dominant EV-A71 genotypes in Taiwan were B5 and C4 but changed to C1 in 2018. Antibody-mediated immunity plays a key role in limiting the EV-A71 illness in humans. However, the level of neutralizing activities against genotype C1 virus by human polyclonal and monoclonal antibodies (MAbs) remains largely unclear. In the study, we demonstrated that that 39% (9 in 23) of post-infection sera from the genotype B5- or C4-infected patients in 2014–2017 exhibit reduced titers with the 2018–2019 genotype C1 viruses than with the earlier B5 and C4 viruses tested. This finding with polyclonal sera is confirmed with human MAbs derived from genotype B5 virus-infected individuals. The 2018–2019 genotype C1 virus is resistant to the majority of canyon-targeting human MAbs, which may be associated with the residue change near or at the bottom of the canyon region on the viral capsid. The remaining three antibodies (16-2-11B, 16-3-4D, and 17-1-12A), which target VP1 S241 on the 5-fold vertex, VP3 E81 on the 3-fold plateau and VP2 D84 on the 2-fold plateau of genotype C1 viral capsid, respectively, retained neutralizing activities with variable potencies. These neutralizing antibodies were also found to be protective against a lethal challenge of the 2018–2019 genotype C1 virus in an hSCARB2-transgenic mice model. These results indicate that the EV-A71-specific antibody response may consist of a fraction of poorly neutralizing antibodies against 2018–2019 genotype C1 viruses among a subset of previously infected individuals. Epitope mapping of protective antibodies that recognize the emerging genotype C1 virus has implications for anti-EV-A71 MAbs and the vaccine field.

Inhibition of 2C Coxsackie B Virus Protein to Decrease Pathogenicity of Diabetes Mellitus Type 1.

Insulin-dependent Diabetes Mellitus Type 1 (T1D) also referred to as autoimmune diabetes. T1D is a chronic disease which is characterized by way of insulin deficiency. The deficiency is due to the loss of pancreatic β cells and leads to hyperglycemia. There are many factors which play a significant role in T1D disease pathogenicity including genetic predisposition, the immune system, and environmental factors. The environmental factors may include Coxsackie B4 virus, a small RNA virus. The objective of current in silico study is to identify active lead compounds against Coxsackie B4 virus, a small RNA virus which has been reported in diabetic patients after PCR. There is a need to predict inhibitors against TID caused by Coxsackie B4 viral protein that may be used as a drug against TID in the future. For this purpose, different bioinformatics databases and tools were used. The protein structure generation and validation, retrieval of ligands and their properties analysis were performed by different databases, web servers, and software tools. Moreover, the docking tools were used to identify the target site of the protein and interaction of different inhibitors with the target protein molecule. Based on the analysis, two lead compounds ZINC00034488 and ZINC00034585 were selected as potential drugs. These compounds are non-toxic and have best interaction energy and fulfill Lipinski rule, Veber rule, Ghose Rule, Weighted QED, Unweighted QED and BBB likeness parameters. Our work will help researchers to get an idea about the understanding of chemicals against Coxsackie B4 Viruses and helpful to design a drug and test these chemicals to overcome Diabetes Mellitus Type 1 caused by Coxsackie B4 virus.

Antiviral and virucidal activities of Lucilia cuprina maggots’ excretion/secretion (Diptera: Calliphoridae): first work

Maggots of Lucilia sericata and L. cuprina are a backbone of the maggot debridement therapy. Further, the excretion/secretion (E/S) of these maggots has antibacterial and antifungal activities, nevertheless the antiviral activity of E/S for these maggots still out the focus. This study aimed to evaluate the E/S of L. cuprina maggots against the Rift Valley Fever (RVF) and Coxsackie B4 (CB4) viruses for first time. After collection of the E/S, its cytotoxicity on Vero cells was evaluated and the safe concentration was determined which used to investigate the antiviral and virucidal effect of E/S on the selected viruses. The E/S decreased the titers of the tested viruses compared with that of untreated viruses. The outcome data refer to that the E/S of L. cuprina consider as a promising antiviral and virucidal agent.

Human metapneumovirus prevalence and patterns of subgroup persistence identified through surveillance of pediatric pneumonia hospital admissions in coastal Kenya, 2007\u20132016

BackgroundHuman metapneumovirus (HMPV) is an important respiratory pathogen that causes seasonal epidemics of acute respiratory illness and contributes significantly to childhood pneumonia. Current knowledge and understanding on its patterns of spread, prevalence and persistence in communities in low resource settings is limited.MethodsWe present findings of a molecular-epidemiological analysis of nasal samples from children < 5 years of age admitted with syndromic pneumonia between 2007 and 2016 to Kilifi County Hospital, coastal Kenya. HMPV infection was detected using real-time RT-PCR and positives sequenced in the fusion (F) and attachment (G) genes followed by phylogenetic analysis. The association between disease severity and HMPV subgroup was assessed using Fisher’s exact test.ResultsOver 10 years, 274/6756 (4.1%) samples screened were HMPV positive. Annual prevalence fluctuated between years ranging 1.2 to 8.7% and lowest in the recent years (2014–2016). HMPV detections were most frequent between October of one year to April of the following year. Genotyping was successful for 205/274 (74.8%) positives revealing clades A2b (41.0%) and A2c (10.7%), and subgroups B1 (23.4%) and B2 (24.9%). The dominance patterns were: clade A2b between 2007 and 11, subgroup B1 between 2012 and 14, and clade A2c in more recent epidemics. Subgroup B2 viruses were present in all the years. Temporal phylogenetic clustering within the subgroups for both local and global sequence data was seen. Subgroups occurring in each epidemic season were comprised of multiple variants. Pneumonia severity did not vary by subgroup (p = 0.264). In both the F and G gene, the sequenced regions were found to be predominantly under purifying selection.ConclusionSubgroup patterns from this rural African setting temporally map with global strain distribution, suggesting a well-mixed global virus transmission pool of HMPV. Persistence in the local community is characterized by repeated introductions of HMPV variants from the global pool. The factors underlying the declining prevalence of HMPV in this population should be investigated.

ЭТИОЛОГИЧЕСКАЯ СТРУКТУРА ЭНТЕРОВИРУСНЫХ ИНФЕКЦИЙ В РОССИЙСКОЙ ФЕДЕРАЦИИ В 2017–2018 ГГ.

Type of enterovirus was detected in 2753 cases when examining 4122 patients with various clinical forms of enterovirus infection (EVI) during the 2017-2018 period. We identified viruses of 42 types belonging to Enterovirus A-B-С species. The ratio of EV-A: EV-B: EV-C species was 51.29 percent: 47.06 percent: 1.65 percent. In 413 environment samples 29 non-polio enteroviruses were identified, three of which, CA14, EVA76 and ECHO25, were not detected in the period in patients with EVI. The Coxsackie A6 virus, which caused a drastic increase in the morbidity of exanthema forms was the dominant agent in the etiological structure of EVI in 2017 in most areas; the leading etiological agents of enteroviral meningitis (ECM) were the ECHO30, ECHO9, ECHO18 viruses. There was a decrease in the morbidity of both all forms of EVI and computers due to a decrease in the activity of the circulation of epidemic variants of the Coxsackie A6 and ECHO30 viruses as a whole in Russia in 2018. The computer epidemic process in 2018 was supported by the become active or remained active viruses of ECHO6, Coxsacke B5, ECHO9, ECHO18 and other viruses of the Enterovirus B species. The remaining relatively high morbidity of exanthema forms of EVI in addition to the Koksaki A6 virus was supported by the activated viruses Koksaki A16, Koksaki A5 and other viruses of the Enterovirus A species. The results of phylogenetic analysis of genome sequences that dominated etiological agents of EVI indicate that in 2018 there was a multiple importation of enterovirus epidemic variants into the territory of the Russian Federation, which supported the EVI / computer epidemiological process in the Russian Federation as a whole and caused a complication of the epidemiological situation in a number of subjects. It is possible that these events contributed to the arrival of a large number of fans at the 2018 FIFA World Cup and visa-free entry into the territory of the Russian Federation for this category of tourists until the end of the year.

Phylogenetic analysis of influenza B viruses in Qingdao from 2011 to 2018

Objective To investigate the molecular epidemiological characteristics of hemagglutinin (HA) and neuraminidase (NA) of influenza B viruses (IBV) isolated in Qingdao from 2011 to 2018. Methods A total of 12 236 samples of influenza-like cases in Qingdao from 2011 to 2018 were collected to extract viral RNAs. All samples were screened for influenza A viruses (IAV) and IBV by one-step multiplex real-time RT-PCR. Lineages of IBV were identified. One hundred and eighty-two strains of IBV were selected to amplify HA and NA genes by RT-PCR and then analyzed by sequencing. Phylogenetic analysis and variation analysis of genes and amino acids were carried out. Results IBV was detected almost every year in Qingdao from 2011 to 2018. The positive rate was only slightly lower than that of IAV (4.99% vs 6.21%). B/Victoria linkage had two prominent epidemic years (2011-2012, 2015-2016), while B/Yamagata linkage had three (2013-2014, 2014-2015, 2017-2018). Most of the infected people were children under 10 years old, and the people infected with the two lineages had similar age characteristics. Phylogenetic analysis of HA genes showed clusters in Victoria clades of 1A and 1B and Yamagata clades of 2 and 3. IBV of Yamagata lineage had more amino acid mutation sites than those of Victoria lineage in HA genes with greater genetic diversity. The B/Yamagata strains had 12 amino acid mutations and the B/Victoria strains had seven in four major epitopes. In the receptor binding sites, two amino acid mutations were detected in the B/Yamagata strains and three in the B/Victoria strains. In Qingdao, 26 strains of IBV were intra-lineage reassortments, mostly of the B/Victoria lineage, and 23 strains were inter-lineage reassortments, mostly between HA-B/Yamagata and NA-B/Victoria strains. A possible resistant strain to NA inhibitor was found. Conclusions The significance of IBV in seasonal influenza should not be neglected. Amino acid substitution, insertion/deletion and gene reassortment were the main strategies for the natural evolution of IBV. Influenza surveillance was of great importance and influenza vaccine strains needed to be updated in time. Key words: Influenza B virus; Hemagglutinin (HA) gene; Neuraminidase (NA) gene; Phylogenetic analysis

Molecular characterization of measles viruses in China: Circulation dynamics of the endemic H1 genotype from 2011 to 2017.

Due to the Expanded Program on Immunization (EPI) and supplementary immunization activities (SIAs) in China, the incidence of measles in China has decreased extensively. The incidence reached its lowest levels in contemporary history in 2012 and 2017, with incidence rates of 4.6 and 4.3 per million population, respectively. However, more than 147,000 measles cases were reported from 2013 to 2016. Furthermore, the proportions of cases in infants < 8 months and adults have been increasing since 2013, representing a considerable challenge for measles elimination in China. A total of 14,868 measles viruses were isolated from confirmed measles cases from 2011 to 2017, of which 14,631 were identified as the predominant endemic genotype, H1; 87 were identified as genotype A viruses that were vaccine associated strains; and 150 were identified as non-H1 genotype viruses. The non-H1 genotype viruses included 62 D8 viruses, 70 D9 viruses, 3 D11 viruses, 14 B3 viruses, and 1 G3 virus, which were identified as imported or import-related viruses that caused sporadic cases or small outbreaks. Most of the transmission chains detected during the period 2011–2012 were interrupted and were followed by many new transmission chains of unknown origin that spread, causing a large measles resurgence in China during 2013–2016. After 4 years of measles resurgence and continuous implementation of the routine immunization program and SIAs, the population immunity reached a sufficiently high level to interrupt most of the transmission chains; only a few strains survived, which continued to be sporadically detected in China in 2017. In the present study, the results from the combined epidemiological and molecular virological data demonstrated the great progress towards measles elimination in China by the further analysis of circulation dynamics for the endemic H1 genotype measles virus from 2011 to 2017. And this study accumulated critical baseline data on circulating wild-type measles viruses in China and provides comprehensive information to the world. These comprehensive baseline data provide evidence to support measles elimination in the future, not only in China but also in other countries worldwide. In addition, the information will be very useful to other countries for tracing their sources of measles cases and for identifying transmission links, which can help prevent potential measles outbreaks.

Relation of Coxsackie B3 and B4 Viral Infections for Development of type 1 Diabetes Mellitus in Children: A Case-Control Study

Background: Human Type 1 diabetes (T1D), previously called Juvenile-onset diabetes is one of the most common chronic, multifactorial diseases of autoimmune origin with a strong genetic component, affecting about 542 000 children in the world and represents about 5-10% of all cases of diabetes. Human enteroviruses (HEVs), particularly Coxsackie B viruses (CVBs), might trigger the onset of type 1 diabetes (T1D). Objectives: Find out any relation between the Coxsackie virus type B3 & B4 infections in addition to GAD65 autoantibodies and the development of T1DM Patients and Methods: A matched case-control study was conducted and sixty cases and 120 controls were enrolled in the study.Enzyme-Linked Immunoassay (ELIZA) technique was used to detect IgM and IgG in serum against the Coxsackie B3 , B4 and GAD65 (Glutamic Acid Decarboxylase 65) autoantibodies of both cases and controls. Qualitative detection of the RNA of the Coxsackie B3 & B4 viruses in the cases and controls by the conventional PCR method using suitable primers in both cases and control. Molecular detection of the CB3 and CB4 RNA was done using according to the manufacturers’ instruction. Results:The following risk factors were found to be independently associated with illness, it were significantly associated with illness and at higher risk of T1DM : CB4 IgM Positivity (OR 47 [95% = 6.1-364.1], p = 0.0002).), CB4 RNA Positive (OR 39.6 [95%CI= 5.1 – 309], p = 0.0004 IgG Antibodies against both CVB3 and GAD65 (OR 32.9 [95%CI = 4.2 - 258.7], p = 0.0009). , GAD65 IgG Positivity (OR 11.8 [95% CI = 4.4 – 31.2], p = 0.001).and IgM Antibodies against both CB4 andGAD65 (OR 8.8 [95%CI = 2.7 – 28.2], p = 0.0002). other risk factors like CB3 IgM Positivity (OR 1.7 [95%CI = 0.6 – 4.5] p= 0.2),CB3 IgG Positivity((OR 1.3 [95%CI = 0.7-2.4], p=0.3).CB4 IgG Positivity(OR 2.1 [95%CI = 0.9-44], p = 0.06) and IgM -Antibodies against both CB3andGAD65 ((OR 1.3 [95%CI = 0.3 – 5.0], p = 0.6) with a moderately increased risk of illness, but these were not statistically significant. CB3 RNA Positive (OR 0.8 [95%CI= 0.3 -1.9] p = 0.6), GAD65 IgM Positivity (OR 0.7 [95%CI = 0.4 – 1.5], p = 0.7), IgG Antibodies against both CB4-GAD65 (OR 0.9 [95%CI = 2.9 – 8.8], p = 0.05) was not associated with illness as these were not statistically significant with the decreased risk of illness and has protective role against infection with T1D. Conclusions: We propose that children aged less than 17 years are at risk of T1D infection if exposure to CB4 whereas CB3 has protective role.

Evolutionary histories of coxsackievirus B5 and swine vesicular disease virus reconstructed by phylodynamic and sequence variation analyses

Coxsackievirus (CV)-B5 is a common human enterovirus reported worldwide; swine vesicular disease virus (SVDV) is a porcine variant of CV-B5. To clarify the transmission dynamics and molecular basis of host switching between CV-B5 and SVDV, we analysed and compared the VP1 and partial 3Dpol gene regions of these two viruses. Spatiotemporal dynamics of viral transmission were estimated using a Bayesian statistical inference framework. The detected selection events were used to analyse the key molecules associated with host switching. Analyses of VP1 sequences revealed six CV-B5 genotypes (A1–A4 and B1–B2) and three SVDV genotypes (I–III). Analyses of partial 3Dpol revealed five clusters (A–E). The genotypes evolved sequentially over different periods, albeit with some overlap. The major hub of CV-B5 transmission was in China whereas the major hubs of SVDV transmission were in Italy. Network analysis based on deduced amino acid sequences showed a diverse extension of the VP1 structural protein, whereas most sequences were clustered into two haplotypes in the partial 3Dpol region. Residue 178 of VP1 showed four epistatic interactions with residues known to play essential roles in viral host tropism, cell entry, and viral decoating.

Development of a high-growth enterovirus 71 vaccine candidate inducing cross-reactive neutralizing antibody responses

Although Enterovirus 71 (EV71) has only one serotype based on serum neutralization tests using hyperimmune animal antisera, three major genogroups (A, B and C) including eleven genotypes (A, B1-B2, and C1-C5) can be well classified based on phylogenetic analysis. Since 1997, large-scale EV71 epidemics occurred cyclically with different genotypes in the Asia-Pacific region. Therefore, development of EV71 vaccines is a national priority in several Asian countries. Currently, five vaccine candidates have been evaluated in clinical trials in China (three C4 candidates), Singapore (one B2 candidate), and Taiwan (one B4 candidate). Overall, the peak viral titers of these 5 vaccine candidates could only reach about 107 TCID50/mL. Moreover, genotypes of these 5 candidates are different from the current predominant genotype B5 in Taiwan and South-Eastern Asia. We adapted a high-growth EV71 genotype B5 (HG-B5) virus after multiple passages and plaque selections in Vero cells and the HG-B5 virus could reach high titers (>108 TCID50/mL) in a microcarrier-based cell culture system. The viral particles were further purified and formulated with alum adjuvant. After two doses of intramuscular immunization in rabbits, the HG-B5 vaccine candidate could induce cross-reactive neutralizing antibodies against the three major EV71 genogroups. In conclusion, a high-growth EV71 virus was successfully adapted in Vero cells and could induce broad spectrum neutralizing antibody titers against three (A, B5, and C4) genotypes in rabbits.

Identification of measles virus genotype B3 associated with outbreaks in Islamabad, Pakistan, 2013-2015.

Measles virus infection remains a significant cause of childhood mortality and morbidity despite continued global efforts and the availability of a safe and effective vaccine. Molecular analysis of indigenous measles viruses could provide critical information on outbreak linkages and transmission pathways that can aid the implementation of appropriate control programs in Pakistan. Blood samples and throat swabs were collected from subjects suspected with measles in Islamabad, Pakistan from 2013 to 2015. Serum samples were tested for the presence of measles immunoglobulin M (IgM) antibodies using enzyme-linked immunosorbent assay (ELISA) while throat swabs were used for the isolation (Vero/SLAM cell line) and subsequent characterization and phylogenetic analysis of measles strains. Of 373 blood samples, 66% tested positive for measles IgM. Male subjects were more often infected (58%) than female (42%) with the highest frequency of positive cases (63%) in the 0-5-years age group. Among the positive cases, only 13% had received one or two doses of the measles vaccine, while 87% were unvaccinated. Of 80 throat swabs, 29 (36%) showed a measles virus-specific cytopathic effect (CPE) and were characterized as genotype B3 through partial sequencing of the nucleoprotein (N) gene. Phylogenetic analysis revealed the Pakistani B3 strains to be closely related to strains from neighboring countries (Iran and Afghanistan) as well as with B3 viruses from the USA, Germany, and the UK. The study results showed that despite the availability of an effective vaccine, the burden of measles infections is very high in Pakistan due to poor routine immunization coverage even in major cities, including the capital city of Islamabad. It is imperative that national health authorities take urgent strategic steps to improve routine immunization and implement adequate molecular identification methods to tackle future measles outbreaks.

Performance Evaluation of the Alere i Influenza A&B Rapid Diagnostic Test, 2016

Influenza is an annually occurred infectious disease, causing severe infections and death among human cases. The use of rapid influenza diagnostic tests (RIDTs) facilitates antiviral prescription for influenza treatment, reduces the need for unnecessary antibacterial agents and allows the implementation of infection control measures. In this study, we evaluated a new RIDT, the Alere i Influenza A&B, for its detection ability against both influenza A and B viruses and compared to real-time RT-PCR assay. A total of 112 throat swab specimens were tested. Compared with the results of real-time RT-PCR assay, the Alere i assay exhibited a detection rate of 43.8% for influenza A viruses with cycle of crossing point (Cp) value ranged from 28-35, and 38.5% for B viruses at Cp value of 26-33, respectively. Detailed analysis showed that the assay had better detection ability of 88% toward influenza A viruses when Cp value was in the range of 28-29. In contrast, no significant difference was observed for the detection ability toward influenza B viruses when the Cp value was lower than 33. The evaluated specificity of Alere i Influenza A&B was 100%. These data indicate that this new RIDT provides fairly accurate results against influenza A viruses, highlighting the future applications for clinical diagnosis of influenza infections.

Polymyalgia Rheumatica After Influenza Vaccine

Influenza is an acute upper respiratory tract infection that occurs in epidemics almost every year, and is caused by influenza A and B viruses. It can cause serious complications including death especially in older adults and individuals with underlying health problems. Influenza vaccination is a very effective way of preventing influenza and is recommended by CDC. The common side effects of the vaccine vary from mild injection site reactions, to rhinorrhea, nasal congestion, headache and sore throat. On the other hand, there have been very rare reports of Guillain-Barre’s syndrome and also some cases of polymyalgia rheumatica (PMR) after influenza vaccine. Our patient, an 86-year-old female, presented with bilateral shoulder and hip pain, and stiffness 2 weeks after she received her influenza vaccine, and both the patient and family were very adamant and upset that the problem was caused by the vaccination. Patient’s erythrocyte sedimentation rate and C-reactive protein were elevated, a clinical diagnosis of PMR was made, and she was started on steroids to which she had a dramatic response. While we strongly recommend the administration of influenza vaccination, we also want to create awareness among the clinicians of this possibility, and proper education of the patients regarding this existence and the fact that if it happens at all, there is a treatment for it, and it should not discourage the patients from getting the vaccine in future. Also this association would need more studies in future. J Med Cases. 2017;8(4):117-118 doi: https://doi.org/10.14740/jmc2788w

Genetic diversity of currently circulating rubella viruses: a need to define more precise viral groups.

Recent studies have shown that the currently circulating rubella viruses are mostly members of two genotypes, 1E and 2B. Also, genetically distinct viruses of genotype 1G have been found in East and West Africa. This study used a Mantel test to objectively include both genetic diversity and geographic location in the definition of lineages, and identified statistically justified lineages (n=13) and sub-lineages (n=9) of viruses within genotypes 1G, 1E and 2B. Genotype 2B viruses were widely distributed, while viruses of genotype 1E as well as 1G and 1J were much more geographically restricted. This analysis showed that more precise groupings for rubella viruses are possible, which should improve the ability to track rubella viruses worldwide. A year-by-year analysis revealed gaps in surveillance that need to be resolved in order to support the surveillance needed for enhanced control and elimination goals for rubella.