Search Results (32)

Neonatal diarrhea remains a significant threat to piglet health, resulting in substantial economic losses worldwide. Among the viral pathogens associated with this condition, rotavirus (RV) has been extensively reported in Brazil; however, lineage-level classification of circulating strains remains limited. This study aimed to characterize G and P genotypes of porcine RV field strains associated with diarrhea in piglets in Southern Brazil. A total of 10 fecal samples were collected by field veterinarian from diarrheic suckling piglets aged 1 to 14 days and analyzed by RT-PCR for the detection of RV species A, B, C, and H. RV species A (RVA) was detected in 90% (9/10) of the samples, while no other RV species were identified. Genotyping based on the VP7 and VP4 genes revealed a single G3P[6] genotype combination in all RVA-positive samples. Nucleotide (nt) and deduced amino acid (aa) sequence analysis revealed high genetic similarity among strains, with values of up to 99.3% for nt and 98.0% for aa of the VP7 gene and 100% for the VP4 gene (nt and aa). Phylogenetic analysis indicated that the VP7 sequences clustered with Brazilian G3 strains, forming a distinct group consistent with a novel lineage (putative G3-XII), whereas VP4 sequences supported a new sublineage (putative P[6]-Ig). These findings demonstrate low genetic variability of RVA field strains in this neonatal diarrhea outbreak, suggesting the circulation of a single viral population. They also emphasize the importance of continuous molecular surveillance to gain a deeper understanding of viral evolution and transmission dynamics in swine populations. Full article

Acute Diarrheal Disease (ADD) remains a major global health concern, with rotavirus A (RVA) and human adenovirus (HAdV) as key viral agents. This study evaluated the positivity rate and molecular characterization of RVA and HAdV in fecal samples from 114 children (0–5 years) in Goiás, Brazil, between January 2022 and December 2023, following the COVID-19 public health emergency. RVA was detected in 13.1% of samples (genotypes G1 and G6 associated with P[8]) and HAdV in 15.8% (genotypes A31, B3, C1, and C6), with two coinfection cases also being detected (1.7%). RVA predominated in unvaccinated 0-to-6-month-old children, while most asymptomatic cases occurred among vaccinated children. HAdV was also mainly identified in this age group, including asymptomatic children. Viral positivity was more common among children without access to treated water. In conclusion, this study underscores the ongoing circulation and genetic diversity of RVA and HAdV among children in Goiás in the post-pandemic period. The findings highlight the influence of vaccination coverage and sanitation on viral positivity, emphasizing the need for integrated public health strategies. Continuous molecular surveillance remains essential to detect emerging genotypes and guide effective prevention and control measures against ADD. Full article

Rotaviruses (RVs) are an important cause of piglet diarrhea. This study aimed to determine the prevalence of rotavirus A, B, and C (RVA, RVB and RVC) in two RVA-vaccinated (VAC) and four non-vaccinated (NON-VAC) farms, and the impact of RVA vaccination on production parameters. Additionally, RVs prevalence in consecutive weekly groups from one vaccinated and one non-vaccinated farm was assessed. Diarrheic feces or ileum content were screened for RVs using real-time RT-PCR. In VAC, no RVA or RVB was detected, while RVC was found in all the samples (15/15). In NON-VAC, RVA, RVB, and RVC were detected in 10.5%, 13.2%, and 52.6% of samples, respectively. RVC was the most prevalent species in longitudinal study, while RVA was found in single samples. RVB was detected in one sample from the vaccinated farm, and in four out of five groups from the non-vaccinated farm. The pre-wean mortality and weaning weight were lower in the vaccinated than in the non-vaccinated farm. Low RVA prevalence and no noticeable improvement in weaning outcomes suggest vaccination was probably unjustified. Our study emphasizes the importance of comprehensive screening before and after vaccination and highlights the importance of including RVB and RVC in diagnostics of neonatal diarrhea. Full article

Porcine Rotavirus (PoRV), a predominant causative agent of neonatal diarrhea in piglets, shares substantial genetic homology with human rotavirus and represents a considerable threat to both public health and the global swine industry in the absence of specific antiviral interventions. The VP6 protein, an internal capsid component, is characterized by exceptional sequence conservation and robust immunogenicity, rendering it an ideal candidate for viral genotyping and vaccine development. In the present study, the recombinant plasmid pET28a(+)-VP6 was engineered to facilitate the high-yield expression and purification of the VP6 antigen. BALB/c mice were immunized to generate monoclonal antibodies (mAbs) through hybridoma technology, and the antigenic specificity of the resulting mAbs was stringently validated. Subsequently, a panel of truncated protein constructs was designed to precisely map linear B-cell epitopes, followed by comparative conservation analysis across diverse PoRV strains. Functional validation demonstrated that all three mAbs exhibited high-affinity binding to VP6, with a peak detection titer of 1:3,000,000 and exclusive specificity toward PoRVA. These antibodies effectively recognized representative genotypes such as G3 and X1, while exhibiting no cross-reactivity with unrelated viral pathogens; however, their reactivity against other PoRV serogroups (e.g., types B and C) remains to be further elucidated. Epitope mapping identified two novel linear B-cell epitopes, ¹²⁸YIKNWNLQNR¹³⁷ and ¹³⁸RQRTGFVFHK¹⁴⁷, both displaying strong sequence conservation among circulating PoRV strains. Collectively, these findings provide a rigorous experimental framework for the functional dissection of VP6 and reinforce its potential as a valuable diagnostic and immunoprophylactic target in PoRV control strategies. Full article

Group A rotavirus (RVA) is the leading cause of acute gastroenteritis in infants and young children worldwide. To elucidate the molecular epidemiology of G2P[4] rotavirus in China and the protective effects of vaccines, whole-genome analysis of 13 G2P[4] RVA strains collected from China in 2022 was performed. Twelve strains possessed the typical DS-1-like genome constellation G2-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Only GS2265 possessed the genome constellation G2-P[4]-12-R2-C2-M2-A2-N2-T2-E1-H2. With the exception of the NSP4 segment of GS2265, all other sequences of the 13 G2P[4] RVA strains clustered within the same lineage on phylogenetic analysis. However, QD2210 and SX2205 were grouped into different branches compared to the other strains. In the VP7 antigenic epitopes, four residues differed from the RotaTeq G2 strain; specifically, A87T and D96N in the 7-1a region and S213D and S242N in the 7-1b region. Comparison of the current G2P[4] RVA strains circulating in China with those circulating globally revealed a high degree of sequence identity. High genetic variability among the newly characterized G2P[4] RVA strains suggest the strains evolve fast. Finally, our data suggest that the multivalent RotaTeq vaccine could have provided better protection than the monovalent Rotarix and LLR. Full article

Porcine rotavirus (PoRV) is a significant enteric pathogen causing gastroenteritis in piglets, which causes huge economic loss to the Chinese pig industry. In this study, six porcine rotavirus A strains were isolated from three adjacent sow farms belonging to the same company within one year, which suffered severe diarrhea outbreaks. AHBZ2303 (G11P[7]) and AHBZ2305 (G9P[23]), AHBZ2304 (G9P[23]) and AHBZ2312 (G4P[6]), AHBZ2310 (G9P[23]) and AHBZ2402 (G5P[23]) were isolated from Farm A, B and C, respectively. All six isolates were related to human rotavirus through complete genome analysis, suggesting the potential cross–species infection between humans and pigs. Evolutionary analysis revealed that AHBZ2303 and AHBZ2304 likely emerged simultaneously in Farm A and B, and then AHBZ2304 was introduced to Farm A and C, leading to the emergence of AHBZ2305 and AHBZ2310. Recombination and large variation were identified for AHBZ2312 and AHBZ2402. These findings provided insights into the transmission and evolution of PoRV among farms and underscored the need for enhanced monitoring to mitigate the risk of outbreaks from novel variants. Full article

The second leading cause of death in children under five years old is diarrheal disease. Probiotics, specifically bifidobacteria, have been associated with a reduction in the number of diarrhea episodes and their severity in babies. In this paper, we summarize the preclinical and clinical evidence of the efficacy of B. longum subsp. infantis IM1^® against various gastrointestinal pathogens using in vitro models, animal models, and clinical studies carried out in our laboratory. The preclinical data demonstrate that IM1^® effectively inhibits rotavirus replication (by up to 36.05%) in MA-104 and HT-29 cells and from infection (up to 48.50%) through the production of an 11-amino-acid peptide. IM1^® displays the capability to displace pathogens from enterocytes, particularly Cronobacter sakazakii and Salmonella enterica, and to reduce the adhesion to the HT29 cells of C. sakazakii and Shigella sonnei. In animal models, the IM1^® strain exhibits in vivo protection against rotavirus and improves the clinical symptomatology of bacterial gastroenteritis. A clinical study involving infants under 3 months of age revealed that IM1^® reduced episodes of diarrhea, proving to be safe, well tolerated, and associated with a lower prevalence of constipation. B. infantis IM1^® emerges as an effective probiotic, diminishing episodes of diarrhea caused by gastrointestinal pathogens. Full article

Rotaviruses (RVs) are known to infect various avian and mammalian hosts, including swine. The most common RVs associated with infection in pigs are A, B, C and H (RVA-C; RVH). In this study we analysed rotavirus strains circulating on a porcine farm in the Western Cape province of South Africa over a two-year period. Whole genomes were determined by sequencing using Illumina MiSeq without prior genome amplification. Fifteen RVA genomes, one RVB genome and a partial RVC genome were identified. Phylogenetic analyses of the RVA data suggested circulation of one dominant strain (G5-P[6]/P[13]/P[23]-I5-R1-C1-M1-A8-N1-T7-E1-H1), typical of South African porcine strains, although not closely related to previously detected South African porcine strains. Reassortment with three VP4-encoding P genotypes was detected. The study also reports the first complete RVB genome (G14-P[5]-I13-R4-C4-M4-A10-T4-E4-H7) from Africa. The partial RVC (G6-P[5]-IX-R1-C1-MX-A9-N6-T6-EX-H7) strain also grouped with porcine strains. The study shows the continued circulation of an RVA strain, with a high reassortment rate of the VP4-encoding segment, on the porcine farm. Furthermore, incidents of RVB and RVC on this farm emphasize the complex epidemiology of rotavirus in pigs. Full article

Rotavirus is the main cause of acute diarrhea in children up to five years of age. In this regard, probiotics are commonly used to treat or prevent gastroenteritis including viral infections. The anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana, by reducing viral infectivity and improving IFN-type I response, has been previously reported. The present study aimed to study the effect of B. longum and/or C. sorokiniana on modulating the antiviral cellular immune response mediated by IFN-γ, IL-10, SOCS3, STAT1, and STAT2 genes in rotavirus-infected cells. To determine the mRNA relative expression of these genes, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection. In addition, infected cells were treated with B. longum and/or C. sorokiniana. Cellular RNA was purified, used for cDNA synthesis, and amplified by qPCR. Our results demonstrated that the combination of B. longum and C. sorokiniana stimulates the antiviral cellular immune response by upregulating IFN-γ and may block pro-inflammatory cytokines by upregulating IL-10 and SOCS3. The results of our study indicated that B. longum, C. sorokiniana, or their combination improve antiviral cellular immune response and might modulate pro-inflammatory responses. Full article

The suboptimal performance of rotavirus (RV) vaccines in developing countries and in animals necessitates further research on the development of novel therapeutics and control strategies. To initiate infection, RV interacts with cell-surface O-glycans, including histo-blood group antigens (HBGAs). We have previously demonstrated that certain non-pathogenic bacteria express HBGA^- like substances (HBGA⁺) capable of binding RV particles in vitro. We hypothesized that HBGA⁺ bacteria can bind RV particles in the gut lumen protecting against RV species A (RVA), B (RVB), and C (RVC) infection in vivo. In this study, germ-free piglets were colonized with HBGA⁺ or HBGA^- bacterial cocktail and infected with RVA/RVB/RVC of different genotypes. Diarrhea severity, virus shedding, immunoglobulin A (IgA) Ab titers, and cytokine levels were evaluated. Overall, colonization with HBGA⁺ bacteria resulted in reduced diarrhea severity and virus shedding compared to the HBGA^- bacteria. Consistent with our hypothesis, the reduced severity of RV disease and infection was not associated with significant alterations in immune responses. Additionally, colonization with HBGA⁺ bacteria conferred beneficial effects irrespective of the piglet HBGA phenotype. These findings are the first experimental evidence that probiotic performance in vivo can be improved by including HBGA⁺ bacteria, providing decoy epitopes for broader/more consistent protection against diverse RVs. Full article

Acute diarrheal disease (ADD) caused by rotavirus (RV) contributes significantly to morbidity and mortality in children under five years of age. Currently, there are no specific drugs for the treatment of RV infections. Previously, we reported the anti-rotaviral activity of the protein metabolites derived from Bifidobacterium adolescentis. In this study, our aim was to assess the impact of B. adolescentis-secreted proteins (BaSP), with anti-rotaviral activity on the human intestinal C2BBe1 cell line. We initiated the production of BaSP and subsequently confirmed its anti-rotaviral activity by counting the infectious foci using immunocytochemistry. We then exposed the C2BBe1 cells to various concentrations of BaSP (≤250 µg/mL) for 72 h. Cell viability was assessed using the MTT assay, cell monolayer integrity was monitored through transepithelial electrical resistance (TEER), and cytoskeleton architecture and tight junctions (TJs) were examined using confocal microscopy with F-actin and occludin staining. Finally, we utilized a commercial kit to detect markers of apoptosis and necrosis after 24 h of treatment. The results demonstrated that BaSP does not have adverse effects on C2BBe1 cells. These findings confirm that BaSP inhibits rotavirus infectivity and has the potential to strengthen intestinal defense against viral and bacterial infections via the paracellular route. Full article

Since 2017, pneumococcal vaccination has evolved from a recommended chargeable vaccination to a mandatory, and therefore free, vaccination for all children. While a 10-valent vaccine is commonly used, parents have the option to use a 13-valent vaccine for a fee. This study aimed to investigate whether and how the introduction of free pneumococcal vaccination affected the uptake of recommended vaccination and to assess the association of chargeable pneumococcal vaccination with recommended vaccination. Data from 1595 vaccination record cards kept by six primary care clinics in urban and rural areas of Poland were collected and analyzed for children born between 2015 and 2018. Belonging to the clinic and the year of birth were the only inclusion criteria. Following the introduction of free universal pneumococcal vaccination, more children were vaccinated with the recommended vaccination (61.2% vs. 66.6%, p = 0.026). The most significant change was in vaccination against rotavirus (48.5% vs. 54.4%, p = 0.018) and against meningococcal B bacteria (4.8% vs. 17.0%, p < 0.001). Children who received chargeable pneumococcal vaccination were also significantly more likely to be vaccinated with recommended vaccines (54.6% vs. 75.9%, p < 0.001). In particular, this was the case for multivalent vaccinations—against rotavirus, chickenpox, and meningococcal C bacteria. Reducing the impact of the economic factor, for example, by introducing free vaccinations, should have a positive impact on the uptake of other recommended vaccinations. Full article

Rotavirus A species (RVA), RVB, RVC, and RVH are four species of rotaviruses (RVs) that are prevalent in pig herds, and co-infections occur frequently. In this study, a quadruplex real-time quantitative RT-PCR (RT-qPCR) for the simultaneous detection of four porcine RVs was developed by designing specific primers and probes based on the VP6 gene of RVA, RVB, RVC, and RVH, respectively. The method showed high specificity and could only detect RVA, RVB, RVC, and RVH, without cross-reaction with other porcine viruses; showed excellent sensitivity, with a limit of detection (LOD) of 1.5 copies/µL for each virus; showed good repeatability, with intra-assay coefficients of variation (CVs) of 0.15–1.14% and inter-assay CVs of 0.07–0.96%. A total of 1447 clinical fecal samples from Guangxi province in China were tested using the developed quadruplex RT-qPCR. The results showed that RVA (42.71%, 618/1447), RVB (26.95%, 390/1447), RVC (42.92%, 621/1447), and RVH (13.68%, 198/1447) were simultaneously circulating in the pig herds, and the co-infection rate of different species of rotaviruses was found to be up to 44.01% (579/1447). The clinical samples were also detected using one previously reported method, and the coincidence rate of the detection results using two methods was more than 99.65%. The phylogenetic tree based on the VP6 gene sequences of RVH revealed that the porcine RVH strains from Guangxi province belonged to the genotype I5, which was closely related to Japanese and Vietnamese strains. In summary, an efficient, sensitive, and accurate method for the detection and differentiation of RVA, RVB, RVC, and RVH was developed and applied to investigate the prevalence of porcine RVs in Guangxi province, China. This study is the first to report the prevalence of porcine RVH in China. Full article

Probiotics are effective to treat or prevent gastrointestinal infections, and microalgae have demonstrated important health-promoting effects and in some cases function as prebiotics. In this regard, the anti-rotavirus effect of Bifidobacterium longum and Chlorella sorokiniana by reducing viral infectivity is well known. However, their effect on immune response against rotavirus has not yet been investigated. Therefore, the aim of this study was to determine the role of Bifidobacterium longum and/or Chlorella sorokiniana in influencing an IFN type I-mediated antiviral response in rotavirus-infected cells. In pre-infection experiments, HT-29 cells were treated with B. longum and C. sorokiniana alone or in combination, followed by rotavirus infection, whereas in post-infection assays, HT-29 cells were treated after infection. The cells’ mRNA was then purified to determine the relative expression level of IFN-α, IFN-β, and precursors of interferons such as RIG-I, IRF-3, and IRF-5 by qPCR. We showed that combination of B. longum and C. sorokiniana significantly increased IFN-α levels in pre-infection and IFN-β in post-infection assays, as compared with individual effects. Results indicate that B. longum, C. sorokiniana, or their combination improve cellular antiviral immune response. Full article

Discrimination and limited access to healthcare services in remote areas can affect vaccination coverage. Therefore, this study aimed to estimate vaccination coverage for children living in quilombola communities and rural settlements in the central region of Brazil during their first year of life and to analyze the factors associated with incomplete vaccination. An analytical cross-sectional study was conducted on children born between 2015 and 2017. The percentage of children who received all vaccines recommended by the National Immunization Program in Brazil by 11 months and 29 days was used to calculate immunization coverage. Children who received the following vaccines were considered as having a complete basic vaccination schedule: one dose of BCG; three doses of Hepatitis B, of Diphtheria-Tetanus-Pertussis (DPT), of Haemophilus influenzae type b (Hib), and of Poliovirus (Polio); two doses of Rotavirus, of 10-valent pneumococcal (PCV10), and of Serogroup C meningococcal conjugate (MenC); and one dose of Yellow Fever (YF). Measles-mumps-rubella (MMR) and other doses recommended at or after 12 months were not included. Consolidated logistic regression was used to identify factors associated with incomplete vaccination coverage. Overall vaccination coverage was 52.8% (95% CI: 45.5–59.9%) and ranged from 70.4% for the Yellow Fever vaccine to 78.3% for the Rotavirus vaccine, with no significant differences between the quilombola and settler groups. Notably, the likelihood of incomplete general vaccination coverage was higher among children who did not receive a visit from a healthcare professional. Urgent strategies are required to achieve and ensure health equity for this unique and traditionally distinct group with low vaccination coverage. Full article