Severe Gastroenteritis Research Articles

Niyangala (Gloriosa Superba) Poisoning Complicated with SIADH

Abstract Background: Niyangala poisoning used to be a common method of deliberate self-harm among people living in rural areas of Sri lanka. It is a plant that grows in the wild and has no usage. All parts of this plant are poisonous.The toxic ingredient in Niyangala is Colchicine. Even though Colchicine poisoning is uncommon, it can lead to life threatening complications and be considered a toxicological emergency. It can cause severe gastroenteritis, abdominal pain, hypotension, electrolyte imbalance in the initial phase, as well as granulocytopenia, thrombocytopenia, clotting defects, hepatic insufficiency and renal failure after the first 24 hours. Case presentation: A 62-year-old male presented to our medical unit with several episodes of severe watery diarrhea 6 hours after the ingestion of 3 tubers of Niyangala. He also had epigastric pain, nausea and vomiting. He had eaten Niyangala after consuming alcohol and claimed it was after a dispute with his wife. On admission, the patient was in pain with some dehydration but he was afebrile. Discussion: SIADH consists of hyponatremia, inappropriately elevated urine osmolality (>100 mOsm/kg), and decreased serum osmolality in a euvolaemic patient. SIADH should be diagnosed when these findings occur in the setting of otherwise normal cardiac, renal, adrenal, hepatic, and thyroid function; in the absence of diuretic therapy; and in the absence of other factors known to stimulate ADH secretion, such as hypotension, severe pain, nausea, and stress. Conclusion: SIADH is a well-recognized complication of colchicine poisoning. We report for the first time SIADH after the ingestion of tubers of Gloriosa superba. Hyponatremia in a patient after poisoning with Gloriosa superba is usually attributed to severe diarrhea which is a common and dominant clinical feature often managed with fluid replacement.

Rotavirus infections in children in Turkey: A systematic review.

We aimed to describe rotavirus epidemiology and clinical findings including extraintestinal manifestations in a setting that has yet to introduce rotavirus vaccines in the national immunization program. A literature search was performed by using the key words "Turkey" and "rotavirus." Ninety-eight studies published between 1987 and 2016 including epidemiological, clinical, and genotypical data at least 1year duration were included. There were a total of 117741 children with diarrhea and 26566 rotavirus gastroenteritis with a median detection rate 31.8% (95% CI, 31.3-32.4) under 5years of age. The rate of dehydration was 47% (95% CI, 23.4-91.6). There were 328 cases reported to be presenting with a various complication related to rotavirus in 2750 children in eight studies. The overall complication rate was 11.7% (95% CI, 10.7-12.9). The cumulative incidence of the most common genotypical combinations circulating worldwide was only 59.7% (G9[P8], 25%; G1[P8], 22%; G2[P4], 5.6%; G3[P8], 2.6%; G4[P8], 4.5%) whereas mixed, untypeable, and other genotypes were 2.4%, 15%, and 22.9% respectively. Our results point out the importance of rotavirus vaccination by presenting that rotavirus may cause severe complications besides severe gastroenteritis. The role of strain diversity in the variability of clinical presentations of rotavirus infections needs to be further investigated.

Detection of novel astroviruses among rodents of Gabon, Central Africa

Astroviruses (AstVs) are mostly responsible for mild to severe gastroenteritis infections in humans and animals. AstVs infect a wide range of host species, have a large genetic diversity with different circulating variants and are thus a high zoonotic risk for human populations. Among these host species, rodents are known to harbor several AstVs variants. Therefore, it is important to identify in rodent species which AstVs are circulating and evaluate their potential zoonotic risk for humans. In this context, this study aimed to screen the presence of AstVs in 267 rodents trapped in 2012 in Franceville and Makokou, two cities in Gabon. RNA extracted from grinded intestines were used for the screening of AstVs by amplification of a conserved region of the RNA dependent RNA polymerase. Results report the identification of AstVs in 12 individuals (4.6% rate), belonging to three different species including Rattus rattus, Mus musculus and Hybomys univittatus. These findings report the first identification of AstVs in R. rattus and H. univittatus. The phylogenetic analyses indicate host specificity of rodents AstVs. The absence of rodent AstVs within the human AstV clade suggests a low rate of interspecies transmission of these viruses and consequently a low zoonotic risk.

2521. The Potential Rise in the Incidence of Rotavirus G3P[8] in Kuwait

BackgroundThe group A rotavirus infections are associated with severe gastroenteritis in children. G1P[8] was the most prevalent genotype found in Kuwait in a study conducted between 2005 and 2006. The demographic change in Kuwait, and the recent decision to include the Rotateq vaccine in the Kuwait national immunization program, prompted us to investigate a potential change in the prevalence of rotavirus genotypes circulating in Kuwait, and to identify the VP4 and VP7 subgenomic lineages.MethodsViral RNA was isolated from the stool samples of 101 children under 5 years of age, hospitalized for severe diarrhea. Rotavirus dsRNA was detected by RT-PCR in 24.7% of children with median age of 1 year.ResultsThe genotype G3P[8] accounted for 47% of cases, followed by G1P[8] (26%), G9P[8] (10.5%), G4P[8] (10.5%), and G9P[4] (5%). Only VP7 nucleotide sequences of rotavirus G3 or G4 type clustered in the same lineage as RotaTeq, while most VP4 nucleotide sequences of rotavirus P[8] type clustered in a different lineage than Rotarix and RotaTeq vaccines.ConclusionOur findings highlight the potential rise in the incidence of rotavirus G3P[8] in Kuwait, and invites future investigations to know whether the recent introduction of RotaTeq vaccine selects for certain genotypes and subgenomic lineages.Disclosures All authors: No reported disclosures.

First genetic detection and characterization of canine parvovirus from diarrheic dogs in Zambia.

Although canine parvovirus (CPV) causes severe gastroenteritis in dogs globally, information on the molecular epidemiology of the virus is lacking in many African countries. Here, 32 fecal samples collected from diarrheic dogs in Zambia were tested for CPV infection using molecular assays. CPV was detected in 23 samples (71.9%). Genetic characterization revealed the predominance of CPV-2c (91.3%). This finding differs from previous reports in Africa, which indicated that CPV-2a and CPV-2b were most prevalent. Phylogenetically, most Zambian CPVs formed a distinct cluster. This is the first report on the molecular characterization of CPV in Zambia.

Molecular characterisation of rotavirus strains detected during a clinical trial of the human neonatal rotavirus vaccine (RV3-BB) in Indonesia

BackgroundThe RV3-BB human neonatal rotavirus vaccine aims to provide protection from severe rotavirus disease from birth. The aim of the current study was to characterise the rotavirus strains causing gastroenteritis during the Indonesian Phase IIb efficacy trial. MethodsA randomized, double-blind placebo-controlled trial involving 1649 participants was conducted from January 2013 to July 2016 in Central Java and Yogyakarta, Indonesia. Participants received three doses of oral RV3-BB vaccine with the first dose given at 0–5 days after birth (neonatal schedule), or the first dose given at ∼8 weeks after birth (infant schedule), or placebo (placebo schedule). Stool samples from episodes of gastroenteritis were tested for rotavirus using EIA testing, positive samples were genotyped by RT-PCR. Full genome sequencing was performed on two representative rotavirus strains. ResultsThere were 1110 episodes of acute gastroenteritis of any severity, 105 episodes were confirmed as rotavirus gastroenteritis by EIA testing. The most common genotype identified was G3P[8] (90/105), the majority (52/56) of severe (Vesikari score ≥11) rotavirus gastroenteritis episodes were due to the G3P[8] strain. Full genome analysis of two representative G3P[8] samples demonstrated the strain was an inter-genogroup reassortant, containing an equine-like G3 VP7, P[8] VP4 and a genogroup 2 backbone I2-R2-C2-M2-A2-N2-T2-E2-H2. The complete genome of the Indonesian equine-like G3P[8] strain demonstrated highest genetic identity to G3P[8] strains circulating in Hungary and Spain. ConclusionsThe dominant circulating strain during the Indonesian Phase IIb efficacy trial of the RV3-BB vaccine was an equine-like G3P[8] strain. The equine-like G3P[8] strain is an emerging cause of severe gastroenteritis in Indonesia and in other regions.

Cost-effectiveness estimates of vaccination against rotavirus in Piedmont, Italy.

Rotavirus-induced gastroenteritis (RVGE) represents the most frequent form of severe gastroenteritis in children. In such a scenario, the availability of an efficient anti-Rotavirus (anti-RV) vaccine represents an effective prevention tool able to prevent those complications mainly linked to the moderate-severe forms of this disease, which require hospital care. The aim of the present study is to estimate the cost effectiveness of universal routine infant RV vaccination program and its budget impact on the Regional Health Service (RHS) of Piedmont, Italy, in order to evaluate the opportunity of the implementation of a national anti-Rotavirus vaccination programme. The researchers performed a cost-effectiveness analysis comparing costs and benefits of a Rotarix two-dose vaccination versus non vaccination and a budget impact analysis (BIA), complementary to the cost-effectiveness analysis. Our results show that the mass implementation of an anti-RV vaccination in Piedmont, in addition to the expected public health benefits, also allows the RHS to save a considerable amount of money within a short period of time, due to the remarkable reduction of direct health costs associated with RVGE management. In fact, as the analysis shows, a universal vaccination against RV results in money-saving for the RHS already from the 2nd year (with a vaccination coverage of 50%). During the five year period, the active and free offer of the anti-RV vaccination would determine a total saving for RHS of about € 503.000. The cost-effectiveness analysis results showed a cost-saving ICER (incremental cost-effectiveness ratio) relevant to the RHS and equal to - €12.197/QALY. In conclusion the adoption of a universal preventive strategy for all the infants in the Piedmont Region may contribute significantly towards the control of RVGE incidence, thus allowing a noteworthy saving of economic and social resources for both the RHS and the general public.

Effect of Rotavirus Vaccination on Acute Diarrheal Hospitalizations Among Low and Very Low Birth Weight US Infants, 2001-2015.

The effectiveness of rotavirus vaccines in low and very low birth weight infants (LBW and VLBW) weighing <2500 and <1500 g at birth, respectively, a high-risk population for severe rotavirus gastroenteritis, has not been well examined. We analyzed inpatient commercial claims data for US children <5 years of age from July 2001 to June 2015. Claims for acute gastroenteritis (AGE) and rotavirus-coded hospitalizations and LBW, VLBW and normal birth weight (NBW) infants were identified. Receipt of rotavirus vaccine was defined using Current Procedural Terminology. Rate reductions were calculated using prevaccine (2001-2006) and postvaccine (2007-2015) annual AGE and rotavirus hospitalization rates. As of December 2014, rotavirus vaccine coverage was 87%, 82% and 64%, for NBW, LBW and VLBW infants, respectively. For 2014-2015, among NBW, LBW and VLBW children <5 years of age, AGE hospitalization rate reductions relative to the prevaccine introduction period were 60% [95% confidence interval (CI): 58%-61%], 64% (95% CI: 57%-70%) and 55% (95% CI: 39%-67%), respectively. Rotavirus hospitalization rate reductions were 91% (95% CI: 90%-92%), 98% (95% CI: 93%-100%) and 93% (95% CI: 70%-98%). Rotavirus vaccines resulted in a 62% (95% CI: 51%-71%), 72% (95% CI: 44%-86%) and 71% (95% CI: 7%-91%) reduction in AGE hospitalization rates comparing vaccinated versus unvaccinated NBW, LBW and VLBW children 3-23 months of age, respectively. Rotavirus vaccines have substantially reduced AGE hospitalizations and are highly effective in LBW and VLBW infants, similar to NBW infants. Efforts to improve vaccination coverage, particularly in LBW and VLBW infants, should continue.

L-Isoleucine Administration Alleviates Rotavirus Infection and Immune Response in the Weaned Piglet Model.

Rotavirus (RV) infection is one of the main pathogenic causes of severe gastroenteritis and diarrhea in infants and young animals. This study aimed to determine how dietary l-isoleucine supplementation improves the growth performance and immune response in weaned piglets with RV infection. In cell culture experiment, after IPEC-J2 and 3D4/31 cells were treated by 8 mM l-isoleucine for 24 h, the gene expressions of β-defensins and pattern recognition receptors (PRR) signaling pathway were significantly increased. Then, in the in vivo experiment, 28 crossbred weaned pigs were randomly divided into two groups fed with basal diet with or without l-isoleucine for 18 days. On the 15th day, the oral RV gavage was executed in the half of piglets. Average daily feed intake and gain of piglets were impaired by RV infection (P < 0.05). RV infection also induced severe diarrhea and the increasing serum urea nitrogen concentration (P < 0.05), and decreased CD4+ lymphocyte and CD4+/CD8+ ratio of peripheral blood (P < 0.05). However, dietary l-isoleucine supplementation attenuated diarrhea and decreasing growth performance (P < 0.05), decreased the NSP4 concentration in ileal mucosa, and enhanced the productions and/or expressions of immunoglobulins, RV antibody, cytokines, and β-defensins in serum, ileum, and/or mesenteric lymph nodes of weaned piglets (P < 0.05), which could be relative with activation of PRR signaling pathway and the related signaling pathway (P < 0.05) in the weaned pigs orally infused by RV. These results indicate that dietary l-isoleucine could improve the growth performance and immune function, which could be derived from l-isoleucine treatment improving the innate and adaptive immune responses via activation of PRR signaling pathway in RV-infected piglets. It is possible that l-isoleucine can be used in the therapy of RV infection in infants and young animals.

Cynomolgus Monkeys (Macaca fascicularis) as an Experimental Infection Model for Human Group A Rotavirus

Group A rotaviruses (RVA) are one of the most common causes of severe acute gastroenteritis in infants worldwide. Rotaviruses spread from person to person, mainly by faecal–oral transmission. Almost all unvaccinated children may become infected with RVA in the first two years of life. The establishment of an experimental monkey model with RVA is important to evaluate new therapeutic approaches. In this study, we demonstrated viral shedding and viraemia in juvenile–adult Macaca fascicularis orally inoculated with Wa RVA prototype. Nine monkeys were inoculated orally: seven animals with human RVA and two control animals with saline solution. During the study, the monkeys were clinically monitored, and faeces and blood samples were tested for RVA infection. In general, the inoculated animals developed an oligosymptomatic infection pattern. The main clinical symptoms observed were diarrhoea in two monkeys for three days, associated with a reduction in plasmatic potassium content. Viral RNA was detected in seven faecal and five sera samples from inoculated animals, suggesting virus replication. Cynomolgus monkeys are susceptible hosts for human Wa RVA infection. When inoculated orally, they presented self-limited diarrhoea associated with presence of RVA infectious particles in faeces. Thus, cynomolgus monkeys may be useful as animal models to evaluate the efficacy of new antiviral approaches.

Assessment of Nutritional Supplements Prescribed in Pregnant Women and Pediatric Patients in Basaveshwara Teaching and General Hospital

Rational use of nutritional supplements is extremely important for better survival of the patient, especially in children where poor nutritional status will cause many co-morbid conditions with an increased risk of death. About 35% of under-five space deaths in the world are associated with malnutrition. Nutrition also place a major role in maternal health poor maternal nutritional status has been related to adverse birth outcomes [1]. The aim of the study was to assess the nutritional supplements prescribed in pregnant women and pediatric patients. A six month hospital based prospective observational study was carried out in the department of pediatric and gynecology at BTGH, Gulbarga. The aim of the study was to assess the nutritional supplements prescribed in pregnant women and pediatric patients at the respective departments. The data was collected in a specially designed data collection form, from the case sheet of inpatient of pediatric department and outpatient of gynecology department enrolled into the study [2]. The study result shows that out of 75 patients in pediatric department, 41 (54.66%) were females and 34(45.33%) were males, malnutrition is more prevalent in toddlers (1-5 years) i.e. 48 patients (64%) when compared to neonates (up to 1 month) 02(2.66%), infants (1month-1year) 20(26.66%), children (5-14years), 5(6.66%).the educational status of their parents 27(36.00%) were grade 0 followed by 19(25.33%) were belonged to grade 1,6(8%) belonged to grade 2,11(14.66%) belonged to grade 3 and 10(13,33%) belonged to grade 4. Out of 75 patients grade 2 PEM 33(44%) is more when compared to grade 1 PEM 7(9.33%), grade 3 PEM 19(25.33%) and grade 4 PEM 16(21.33%). 57 patients were improved 14 patient were discharged under request, 4 patient were referred and 00 deaths are reported [3]. The majority of supplements were administered orally (75%) followed by parenteral route 25% various types of nutrients are prescribed in pediatrics majority including multi vitamin, elemental iron +folic acid, vit A, vit C, zinc acetate, calcium carbonate+vitD3, electrolytes. the majority of prescription were with brand name (73.33%) followed by generic name (26.66%) among the associated co-morbidity conditions with malnutrition bronchopneumonia (13.33%) followed by severe anemia (10.66%), nutritional anemia (12%), acute gastroenteritis (9.33%),pulmonary TB (6.66%) and others [4]. [Table 1-5] Out of 100 pregnant women 50(25%) are of second trimester, 25(25%) are of first trimester, 25(25%) are of third trimester the majority of prescription were with brand name (72%) followed by generic name (28%). Majority of the supplements were administered orally (90%) when compared to parenteral administration (10%). The nutrients prescribed for pregnant women include T.doxinate plus for 47 patients, T.livogen Z (68 patients), T.mecalvit (65 patients), T.orofer XT (19 patients), cap. Becosule (23 patients), protein powder (25 patients), T.folvite (7 patients) [5]. [Table 6-9] The economic and literacy status of the households are the main factors causing nutritional imbalances in children. The number of cases reported concluded the shortage of nutrients to this region and unawareness in pregnant women [6].

Glycan Binding Specificity and Mechanism of Human and Porcine P[6]/P[19] Rotavirus VP8*s.

Rotaviruses (RVs), which cause severe gastroenteritis in infants and children, recognize glycan ligands in a genotype-dependent manner via the distal VP8* head of the spike protein VP4. However, the glycan binding mechanisms remain elusive for the P[II] genogroup RVs, including the widely prevalent human RVs (P[8], P[4], and P[6]) and a rare P[19] RV. In this study, we characterized the glycan binding specificities of human and porcine P[6]/P[19] RV VP8*s and found that the P[II] genogroup RV VP8*s could commonly interact with mucin core 2, which may play an important role in RV evolution and cross-species transmission. We determined the first P[6] VP8* structure, as well as the complex structures of human P[19] VP8*, with core 2 and lacto-N-tetraose (LNT). A glycan binding site was identified in human P[19] VP8*. Structural superimposition and sequence alignment revealed the conservation of the glycan binding site in the P[II] genogroup RV VP8*s. Our data provide significant insight into the glycan binding specificity and glycan binding mechanism of the P[II] genogroup RV VP8*s, which could help in understanding RV evolution, transmission, and epidemiology and in vaccine development.IMPORTANCE Rotaviruses (RVs), belonging to the family Reoviridae, are double-stranded RNA viruses that cause acute gastroenteritis in children and animals worldwide. Depending on the phylogeny of the VP8* sequences, P[6] and P[19] RVs are grouped into genogroup II, together with P[4] and P[8], which are widely prevalent in humans. In this study, we characterized the glycan binding specificities of human and porcine P[6]/P[19] RV VP8*s, determined the crystal structure of P[6] VP8*, and uncovered the glycan binding pattern in P[19] VP8*, revealing a conserved glycan binding site in the VP8*s of P[II] genogroup RVs by structural superimposition and sequence alignment. Our data suggested that mucin core 2 may play an important role in P[II] RV evolution and cross-species transmission. These data provide insight into the cell attachment, infection, epidemiology, and evolution of P[II] genogroup RVs, which could help in developing control and prevention strategies against RVs.

Universal rotavirus vaccination program in Sicily: Reduction in health burden and cost despite low vaccination coverage

ABSTRACTRotavirus is considered the main cause of severe gastroenteritis and nosocomial infections in Pediatric units, especially during late winter and early spring season in temperate region. In 2013 Sicilian Region, for the first time in Italy, introduced universal Rotavirus vaccination. This study aims to estimate health and economic impact on rotavirus Gastroenteritis (RVGE) among children aged 0–59 months in Sicily, after rotavirus vaccine introduction.We analyzed hospital discharge records including a diagnosis of RVGE occurred from 1st January 2009 to 31st December 2016 among hospitalized children aged 0 to 59 months, residents in Sicily. RVGEs were defined as all hospitalizations with an ICD-9-CM diagnosis code of 008.61 on first or any diagnosis position. Also an economic impact analysis on Health Regional System was conducted.We observed a consistent decline of hospitalization after rotavirus vaccination introduction from 394 per 100,000 in 2009–2012 to 220 per 100,000 in 2013–2016. We found a change in the peak of reported cases by at least one month from March-April in the pre-vaccination period to May-June in the post-vaccination period. Since 2013, we estimated that the annual average cost saved is 1,134,056 € when considering direct and indirect costs to health care as well as vaccination costs.Our study is the first analysis conducted as far as we are aware in a high-income setting with poor coverage (lower than 50%), demonstrating a significant reduction of RVGE hospitalizations in Sicily after vaccine introduction. Moreover, was observed a consistent impact of vaccination on health care cost saving.

Generation of Recombinant Rotaviruses Expressing Fluorescent Proteins by Using an Optimized Reverse Genetics System.

An entirely plasmid-based reverse genetics system for rotaviruses was established very recently. We improved the reverse genetics system to generate recombinant rotavirus by transfecting only 11 cDNA plasmids for its 11 gene segments under the condition of increasing the ratio of the cDNA plasmids for NSP2 and NSP5 genes. Utilizing this highly efficient system, we then engineered infectious recombinant rotaviruses expressing bioluminescent (NanoLuc luciferase) and fluorescent (enhanced green fluorescent protein [EGFP] and mCherry) reporters. These recombinant rotaviruses expressing reporters remained genetically stable during serial passages. Our reverse genetics approach and recombinant rotaviruses carrying reporter genes will be great additions to the tool kit for studying the molecular virology of rotavirus and for developing future next-generation vaccines and expression vectors.IMPORTANCE Rotavirus is one of the most important pathogens causing severe gastroenteritis in young children worldwide. In this paper, we describe a robust and simple reverse genetics system based on only rotavirus cDNAs and its application for engineering infectious recombinant rotaviruses harboring bioluminescent (NanoLuc) and fluorescent (EGFP and mCherry) protein genes. This highly efficient reverse genetics system and recombinant group A rotaviruses expressing reporters could be powerful tools for the study of different aspects of rotavirus replication. Furthermore, they may be useful for next-generation vaccine production for this medically important virus.

Norovirus and Rotavirus Disease Severity in Children: Systematic Review and Meta-analysis.

Rotaviruses (RVs) and noroviruses (NoVs) are the most common causes of severe acute gastroenteritis in children. It is generally accepted that RVs cause severe acute gastroenteritis in a higher proportion of cases compared with NoVs. To our knowledge, there are no systematic reviews and meta-analyses comparing the severity of NoV and RV disease. We searched MEDLINE for studies reporting data for NoV and RV medically attended disease severity in children. We included studies where all children had been tested for both NoV (reverse transcription polymerase chain reaction) and RV (enzyme-linked immunosorbent assay or reverse transcription polymerase chain reaction) and that reported disease severity using the Vesikari or modified Vesikari score, or provided clinical information on severity. We generated pooled estimates of the mean with 95% confidence intervals using random effects meta-analysis. We identified 266 publications, of which 31 were retained for qualitative analysis and 26 for quantitative analysis. Fourteen studies provided data on severity score for the meta-analysis. The pooled mean severity scores (95% confidence interval) among outpatients were 10 (8-12) and 11 (8-14) for NoV and RV, respectively. Among inpatients, they were 11 (9-13) for NoV and 12 (10-14) for RV. The difference was statistically significant among inpatients, but relatively small (1 point in a 20-point scale). About 20% more children with RV required rehydration when compared with children with NoV. NoV causes moderate to severe disease similar to RV in young children. This information should be useful for future evaluations of an eventual introduction of NoV vaccines in national immunization programs.

Intragenogroup Recombination in the Complete Genome Sequence of Human Sapovirus Circulating in Bangladesh.

ABSTRACTHuman sapovirus (SaV) is responsible for severe gastroenteritis among infants and children. Research about the genetic configuration of SaV is scarce in Bangladesh. Here, we report the complete genome sequence of an SaV strain with intragenogroup recombination, isolated from an infant with severe diarrhea in Bangladesh in 2005.

Genotypic characterization of rotavirus in children under 5 years circulating in C\xf4te D\u2019Ivoire from 2010 to 2013

BackgroundRotavirus infection is the most common cause of severe gastroenteritis in children under five years of age in both developed and developing countries. The World Health Organisation (WHO) recommends the surveillance of rotavirus strains prior to vaccine introduction in all applicable countries. The objective of this study was to describe the epidemiological characteristics as well as to determine the circulating genotypes of rotaviruses in Côte d’Ivoire prior to vaccine introduction.MethodsThe study included children under five years of age who met the inclusion criteria after informed consent had been sort from their parents or guardians. Rotavirus VP6 antigens were detected for each stool sample using Enzyme Immunoassay (EIA). Genotyping of positive EIA samples was performed by reverse-transcriptase-PCR (RT-PCR) assays.ResultsA total of 684 children were recruited. Children aged between 6 and 11 months were the most represented with 34%. Rotavirus VP6 antigens were found in 27.1% (186/684) of samples tested. Commonly detected G genotypes included G12 (46.6% (82/176) and G1 (13.1% (23/176) whilst P[8] (49.8% (91/183) was the most predominant P genotype. Rotavirus G12P[8] was the most predominant strain circulating in Côte d’Ivoire within the period of study and constituted 26.6% of all strains detected.ConclusionThe monitoring of circulating strains will help guide decision-makers in the choice of vaccine. Genotypic variability of circulating rotavirus strains over the years implies there is a need for continuous rotavirus strain surveillance even after vaccine introduction.

Bovine Nebovirus Interacts with a Wide Spectrum of Histo-Blood Group Antigens.

ABSTRACTSome viruses within the Caliciviridae family initiate their replication cycle by attachment to cell surface carbohydrate moieties, histo-blood group antigens (HBGAs), and/or terminal sialic acids (SAs). Although bovine nebovirus (BNeV), one of the enteric caliciviruses, is an important causative agent of acute gastroenteritis in cattle, its attachment factors and possibly other cellular receptors remain unknown. Using a comprehensive series of protein-ligand biochemical assays, we sought to determine whether BNeV recognizes cell surface HBGAs and/or SAs as attachment factors. It was found that BNeV virus-like particles (VLPs) bound to A type/H type 2/Ley HBGAs expressed in the bovine digestive tract and are related to HBGAs expressed in humans and other host species, suggesting a wide spectrum of HBGA recognition by BNeV. BNeV VLPs also bound to a large variety of different bovine and human saliva samples of all ABH and Lewis types, supporting previously obtained results and suggesting a zoonotic potential of BNeV transmission. Removal of α1,2-linked fucose and α1,3/4-linked fucose epitopes of target HBGAs by confirmation-specific enzymes reduced the binding of BNeV VLPs to synthetic HBGAs, bovine and human saliva, cultured cell lines, and bovine small intestine mucosa, further supporting a wide HBGA binding spectrum of BNeV through recognition of α1,2-linked fucose and α1,3/4-linked fucose epitopes of targeted HBGAs. However, removal of terminal α2,3- and α2,6-linked SAs by their specific enzyme had no inhibitory effects on binding of BNeV VLPs, indicating that BNeV does not use terminal SAs as attachment factors. Further details of the binding specificity of BNeV remain to be explored.IMPORTANCE Enteric caliciviruses such as noroviruses, sapoviruses, and recoviruses are the most important etiological agents of severe acute gastroenteritis in humans and many other mammalian host species. They initiate infection by attachment to cell surface carbohydrate moieties, HBGAs, and/or terminal SAs. However, the attachment factor(s) for BNeV, a recently classified enteric calicivirus genus/type species, remains unexplored. Here, we demonstrate that BNeV VLPs have a wide spectrum of binding to synthetic HBGAs, bovine and human saliva samples, and bovine duodenal sections. We further discovered that α1,2-linked fucose and α1,3/4-linked fucose epitopes are essential for binding of BNeV VLPs. However, BNeV VLPs do not bind to terminal SAs on cell carbohydrates. Continued investigation regarding the proteinaceous receptor(s) will be necessary for better understanding of the tropism, pathogenesis, and host range of this important viral genus.

Organoid and Enteroid Modeling of Salmonella Infection

Salmonella are Gram-negative rod-shaped facultative anaerobic bacteria that are comprised of over 2,000 serovars. They cause gastroenteritis (salmonellosis) with headache, abdominal pain and diarrhea clinical symptoms. Salmonellosis brings a heavy burden for the public health in both developing and developed countries. Antibiotics are usually effective in treating the infected patients with severe gastroenteritis, although antibiotic resistance is on the rise. Understanding the molecular mechanisms of Salmonella infection is vital to combat the disease. In vitro immortalized 2-D cell lines, ex vivo tissues/organs and several animal models have been successfully utilized to study Salmonella infections. Although these infection models have contributed to uncovering the molecular virulence mechanisms, some intrinsic shortcomings have limited their wider applications. Notably, cell lines only contain a single cell type, which cannot reproduce some of the hallmarks of natural infections. While ex vivo tissues/organs alleviate some of these concerns, they are more difficult to maintain, in particular for long term experiments. In addition, non-human animal models are known to reflect only part of the human disease process. Enteroids and induced intestinal organoids are emerging as effective infection models due to their closeness in mimicking the infected tissues/organs. Induced intestinal organoids are derived from iPSCs and contain mesenchymal cells whereas enteroids are derive from intestinal stem cells and are comprised of epithelial cells only. Both enteroids and induced intestinal organoids mimic the villus and crypt domains comparable to the architectures of the in vivo intestine. We review here that enteroids and induced intestinal organoids are emerging as desired infection models to study bacterial-host interactions of Salmonella.

Oral immunization with rotavirus VP7-CTB fusion expressed in transgenic Arabidopsis thaliana induces antigen-specific IgA and IgG and passive protection in mice.

Human rotavirus (HRV) is the primary cause of severe gastroenteritis in children. However, there is currently no protective virus for rotavirus available. In the present study, an HRVVP7-cholera toxin B subunit (CTB) fusion protein was expressed in Arabidopsis thaliana. To determine the adjuvant effect of HRVVP7-CTB, HRVVP7 without CTB was expressed in the same manner. HRVVP7-CTB accounted for 0.39% of the total soluble protein (TSP) in the transgenic seeds and 52.65 µg/g of HRVVP7 protein was expressed in these seeds. Mice were immunized with TSP from the transformed seeds and produced serum immunoglobulin G (IgG) and mucosal IgA specifically directed against HRVVP7. Antibody titers were highest in mice orally immunized with the plant-expressed HRVVP7-CTB protein, whereas HRVVP7-CTB-specific IgG neutralized the rotavirus. Suckling pups born from dams immunized with the HRVVP7-CTB fusion protein were protected against challenge with virulent rotavirus. The results of the present study suggest that the HRVVP7-CTB fusion protein produced in A. thaliana may be a rotaviral-specific candidate subunit vaccine.