Lytic phage W5, a novel isolate derived from poultry/livestock slaughterhouse effluent, displayed potent lysis against nine Salmonella serovars (e.g., Salmonella Typhimurium [S. Typhimurium], Salmonella Choleraesuis, and Salmonella Typhi). Integrated morphometry and genomic phylogeny affirmed its taxonomic placement within Cornellvirus (Guernseyvirinae and Myoviridae). Biological characterization demonstrated that under an optimal multiplicity of infection (MOI) of 1, the latent period was only 22 min, with the phage titer peaking at 3.67 × 10¹¹ PFU/mL during the logarithmic lysis phase (22-70 min). The phage retained stability at 50°C and across an extreme pH range (3-13) while achieving 98% host adsorption within 13 min in SM buffer/glycerol. In food applications, crystal violet staining confirmed that W5 significantly inhibited the growth of S. Typhimurium CMCC 50115 in milk, pork, and fresh eggs (eggshells and egg liquid), effectively preventing biofilm formation and eradicating preformed biofilms. Confocal laser scanning microscopy (CLSM) further verified efficient clearance of both nascent and mature biofilms formed by S. Typhimurium CMCC 50115 after phage W5 treatment under varied temperatures. Field emission scanning electron microscopy (FESEM) revealed potent lytic efficacy of the phage against biofilms on food-contact surfaces such as polypropylene (PP) and polyethylene (PE), with efficacy modulated by biofilm developmental stage and temperature, most prominently demonstrating superior eradication of early-stage biofilms on PE surfaces at 30°C. These findings collectively highlight phage W5's substantial potential as a novel biocontrol agent against Salmonella in the food industry, attributable to its broad-spectrum lytic potency, exceptional environmental resilience, and multi-mechanistic biofilm-clearing properties. Antimicrobial-resistant Salmonella poses a severe threat to food safety and public health, particularly through persistent biofilms on food-processing surfaces and animal-derived products. Traditional disinfection methods often fail against biofilms, while antibiotic overuse accelerates resistance. Bacteriophages offer a targeted, sustainable alternative, but their real-world efficacy in food systems remains underexplored. This study addresses critical gaps by evaluating a novel phage's potential to combat biofilms in relevant food matrices (dairy, meat, and eggs) and on common food-contact surfaces (PP/PE). By demonstrating practical biocontrol under varying storage conditions, this research advances phage-based strategies to enhance food safety while mitigating antimicrobial resistance-a priority for global health and sustainable agriculture. The findings have direct implications for industry sanitation and regulatory approvals for phage applications in food systems.
Rotavirus SA11 (RV SA11), a simian strain and member of group A, is widely used for RV research due to its attenuation and similarity to human strains. This study investigated the effects of food acidifying agents and common food processing and preservation conditions on the survivability of RV SA11. Acetic, citric, and lactic buffers (adjusted to pH 4.0) as simulated buffer systems and real food models, including traditional pickle, orange juice, and a fermented yogurt drink, were inoculated with RV SA11 at an initial titer of 7.22 log10 TCID50/ml. Viral titers were determined after exposing samples to refrigeration (4 °C for 2 and 4 days), room temperature (20 °C for 2 and 6 h), heating (90 °C for 10 and 30 min), and microwave treatment (0.5 and 2 min). At 4 °C, a 4.99 log10 TCID50/ml reduction was observed in the lactic acid system after 4 days, while complete inactivation occurred within 2 days in the citric and 4 days in the acetic systems. At 20 °C, viral titers decreased by 4.45, 3.99, and 3.06 log10 TCID50/ml in lactic, citric, and acetic systems, respectively. Heating at 90 °C completely inactivated the virus within 10 min in lactic and 30 min in acetic systems, while microwave exposure for 2 min eliminated infectivity in both acetic and citric buffers. Viral reductions in real foods after 6 h at 20 °C were lower than in simulated buffers (a range of 2.45 to 3.39 log10 TCID50/ml). Overall, these findings show that food composition and processing conditions significantly influence rotavirus persistence and inactivation in food matrices.
Severe acute respiratory syndrome Coronavirus-2, Norovirus GI and GII have been identified as one of the leading primary agents of lethal diseases such as COVID-19 and acute gastroenteritis, causing critical problems in public health, particularly in children, the elderly, and individuals with weakened immune systems. These pathogens contribute to substantial morbidity, mortality and pose a serious threat to human health, imposing a tremendous economic burden globally. Hence, this study sought to profile the co-occurrence of SARS-CoV-2 and Noroviruses in wastewater collection and treatment facilities within Buffalo City and Amathole District regions, Eastern Cape Province, South Africa. Raw wastewater samples were collected from the wastewater treatment facilities on a weekly basis for a 6-month sampling regime using the grab sampling technique. Total Ribonucleic acids (RNA) were extracted and purified using the commercial Total RNA extraction kits and the extracted RNA sample were further profiled for the presence of SARS-CoV-2 RNA and Noroviruses GI and GII using RT-qPCR. A total of 213 samples were screened using RT-qPCR. SARS-CoV-2 was detected in 146 (69%) samples, Norovirus GI in 58 (27%), Norovirus GII in 25 (12%) and 25 (12%) samples showed co-infection with both GI and GII norovirus targets. The RNA concentration of the extracted samples from wastewater treatment facilities in this study ranged between 102 ng/µl and 12,828 ng/µl. It was observed that the SARS-CoV-2 GC/mL range from 5.22 × 102 to an extreme 2.5650 × 104 GC/mL. The study findings demonstrate a high prevalence of SARS-CoV-2 RNA in wastewater, affirming the utility of wastewater surveillance as an early warning system for potential outbreaks at community levels. Furthermore, the study showed the co-occurrence of SARS-CoV-2 alongside Norovirus GI and GII in wastewater milieu, highlighting an exacerbated potential risk of co-infection and a major threat to public health and environmental safety.
Swine may act as 'epidemiological bridges' and reservoirs for the emergence of novel zoonotic influenza viruses with pandemic potential. While bidirectional exchange of influenza A viruses at the swine-human interface is well recognised, data on the extent of interspecies transmission are limited. We analysed the post-seasonal geometric mean titre (GMT) of influenza A(H1N1)pdm09 antibodies in humans and the seasonal prevalence of influenza A(H1N1)pdm09 antibodies in unvaccinated swine from 2009/2010-2022/2023 per county in Norway to search for evidence of interspecies transmission. We explored correlations at the national and individual county level and investigated possible associations by running a negative binomial regression model. Additionally, we distributed an influenza vaccination questionnaire to veterinarians and farmers working with swine to assess vaccination uptake and calculated total response rates per county and overall. The time series of H1N1pdm09 antibodies from humans and swine show significant positive correlations both across (0.8 Pearson correlation coefficient) and within certain individual counties, with especially high correlations in Innlandet (0.9), Vestland (0.8) and Rogaland (0.7) Counties. Our regression analysis revealed a significant positive association between the annual GMT of H1N1pdm09 antibodies in humans, the annual seroprevalence of H1N1pdm09 antibodies in swine, and the density of swine farms in counties. Vaccination uptake was 39% and 50% in farmers and veterinarians, respectively. Our findings indicate a temporal relationship between the disease in humans and swine; suggesting spillover, environmental factors facilitating disease spread, and/or indirect relationships driven by unknown factors. The time series of H1N1pdm09 antibodies in humans and swine shows significant correlations. Regression analysis links GMT of H1N1pdm09 antibodies in humans to seroprevalence of H1N1pdm09 in swine and density of swine farms. This indicates a temporal relationship possibly due to spillover, shared risk factors or indirect relationships driven by unknown factors. The influenza vaccination survey showed a 39% uptake among farmers and 50% among swine veterinarians.
Information on childhood cancer burden is crucial for effective cancer policy planning. Unfortunately, observed paediatric cancer data are not available in every country, and previous global burden estimates have not discretely reported several common cancers of childhood. We aimed to inform efforts to address childhood cancer burden globally by analysing results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2023, which now include nine additional cancer causes compared with previous GBD analyses. GBD 2023 data sources for cancer estimation included population-based cancer registries, vital registration systems, and verbal autopsies. For childhood cancers (defined as those occurring at ages 0-19 years), mortality was estimated using cancer-specific ensemble models and incidence was estimated using mortality estimates and modelled mortality-to-incidence ratios (MIRs). Years of life lost (YLLs) were estimated by multiplying age-specific cancer deaths by the standard life expectancy at the age of death. Prevalence was estimated using survival estimates modelled from MIRs and multiplied by sequelae-specific disability weights to estimate years lived with disability (YLDs). Disability-adjusted life-years (DALYs) were estimated as the sum of YLLs and YLDs. Estimates are presented globally and by geographical and resource groupings, and all estimates are presented with 95% uncertainty intervals (UIs). Globally, in 2023, there were an estimated 377 000 incident childhood cancer cases (95% UI 288 000-489 000), 144 000 deaths (131 000-162 000), and 11·7 million (10·7-13·2) DALYs due to childhood cancer. Deaths due to childhood cancer decreased by 27·0% (15·5-36·1) globally, from 197 000 (173 000-218 000) in 1990, but increased in the WHO African region by 55·6% (25·5-92·4), from 31 500 (24 900-38 500) to 49 000 (42 600-58 200) between 1990 and 2023. In 2023, age-standardised YLLs due to childhood cancer were inversely correlated with country-level Socio-demographic Index. Childhood cancer was the eighth-leading cause of childhood deaths and the ninth-leading cause of DALYs among all cancers in 2023. The percentage of DALYs due to uncategorised childhood cancers was reduced from 26·5% (26·5-26·5) in GBD 2017 to 10·5% (8·1-13·1) with the addition of the nine new cancer causes. Target cancers for the WHO Global Initiative for Childhood Cancer (GICC) comprised 47·3% (42·2-52·0) of global childhood cancer deaths in 2023. Global childhood cancer burden remains a substantial contributor to global childhood disease and cancer burden and is disproportionately weighted towards resource-limited settings. The estimation of additional cancer types relevant in childhood provides a step towards alignment with WHO GICC targets. Efforts to decrease global childhood cancer burden should focus on addressing the inequities in burden worldwide and support comprehensive improvements along the childhood cancer diagnosis and care continuum. St Jude Children's Research Hospital, Gates Foundation, and St Baldrick's Foundation.
Salmonella is a foodborne pathogen, and the emergence of antimicrobial-resistant (AMR) strains poses a serious global threat to public health. Instead of conventional antibiotics, alternative antimicrobial strategies such as bacteriophages should be considered in the farm-to-fork chain to prevent Salmonella transmission. This study investigated the viability and antimicrobial potential of six Salmonella-specific bacteriophages, each targeting a distinct serotype, including one jumbo phage (MET P1-082). Phage stability was first evaluated after lyophilization to determine whether the bacteriophages remained viable following this process. In addition, their stability was tested under different conditions of pH (4 and 7), temperature (4, 15, and 25°C), and salinity (0.9% and 10%) at multiple time intervals (1 h, 1 day, and 1 week). Phage titers were determined using the double agar overlay plaque assay. Based on the stability results, the antimicrobial efficacy of the phages was tested against Salmonella in artificially contaminated food matrices, including chicken feed (25°C), chicken meat (4°C), and lettuce (4°C). Reductions in Salmonella counts were quantified on Xylose Lysine Deoxycholate (XLD) agar plates. Titers of lyophilized phages showed average decrease of 1.3 log10 PFU mL-1. While most phages retained high stability, only MET P1-082 and MET P1-103 remained viable after 1 week at pH 4 (P < 0.001), despite a noticeable decrease in titer. Among the tested phages, the one targeting S. Kentucky achieved the highest reduction (5 log10 CFU g-1) in chicken feed after 24 h (P < 0.01). On chicken meat, the S. Infantis phage provided a 2.97 log10 CFU g-1 reduction after 24 h, while the S. Hadar phage resulted in a 2.76 log10 CFU g-1 reduction on lettuce after 1 week. The findings demonstrate that the tested bacteriophages remained stable under tested environmental conditions and effectively reduced at least 1 log10 CFU g-1 of Salmonella load in contaminated chicken feed, meat, and lettuce. These results highlight their potential as practical biocontrol agents in food safety applications.
Under a One Health framework, viruses of veterinary and zoonotic importance pose significant threats to animal and human health, food security, and livelihoods, particularly in regions with intense human-animal interactions. In West Africa, despite recent advances in surveillance programs, important gaps remain in understanding viral diversity and cross-species transmission at wildlife-livestock interfaces. We conducted metagenomic surveillance to characterize viruses circulating across livestock, domestic animals, and wildlife in rural Ghana in 165 animals sampled across five regions. Viral RNA from serum and tissue samples was sequenced with the Illumina platform, and genomes were de novo assembled with MEGAHIT. Phylogenetic relationships were reconstructed using Bayesian approaches. We report the first genomic sequences of porcine parvovirus 3, canine parvovirus, rotavirus A genotype R16, and bovine hepacivirus subtype B from Ghana in over a decade. Phylogenetic analyses revealed intercontinental linkages between Africa and Europe for parvoviruses, persistence of hepacivirus lineages, and evidence of cross-species transmission for rotavirus. Notably, detection in apparently healthy animals highlights underrecognized circulation, gaps in vaccination effectiveness, trade-related biosecurity vulnerabilities, and the role of wildlife in viral maintenance and transmission. Our findings reveal dynamic viral diversity and connectivity across animal populations and ecological interfaces, emphasizing the fluid and interconnected nature of pathogen circulation within One Health systems. By integrating metagenomics and phylogenetics, this study provides a scalable framework for enhancing surveillance capacity, enabling the early detection of emerging threats and informing targeted strategies to mitigate zoonotic and economically important viral diseases in West Africa.
Enterococcus hirae is an opportunistic pathogen capable of causing severe bacteremia and intestinal infections, thereby posing a threat to food safety. The rise of multidrug resistance driven by antibiotic misuse, coupled with pervasive drug residues in food and the environment, necessitates the development of alternative therapeutic agents. Bacteriophages, which lyse host bacteria with high specificity without causing pollution, represent a promising class of eco-friendly bio-bactericides. In this study, 158 environmental samples were collected from wastewater treatment plants in Xinjiang, leading to the isolation of 13 E. hirae phages. Through systematic comparison, a novel phage vB_EhiS_LPP isolated from a wastewater treatment plant in Shihezi City, was selected for further investigation. This phage displays large plaques, a high titer, a short latent period, a large burst size, and excellent environmental stability. Functional assays further demonstrated that vB_EhiS_LPP exerts strong lytic activity against E. hirae isolates even at a low multiplicity of infection (MOI = 0.01). Whole genome analysis revealed that vB_EhiS_LPP shares less than 10% average nucleotide identity with known Enterococcal phages, suggesting that it may represent a new genus. Further safety assessment confirmed the absence of antibiotic resistance genes and virulence factors in the vB_EhiS_LPP genome. Moreover, this bacteriophage does not cause hemolysis in chicken red blood cells, supporting its compliance with food safety standards. Application evaluation in a food model showed that vB_EhiS_LPP effectively eliminated E. hirae within 6 to 10 h and significantly delayed food spoilage, highlighting its potential as a green bio-preservative agent in the food industry.
Escherichia coli O157:H7 is a major foodborne pathogen characterized by its low infectious dose, strong environmental persistence, and robust biofilm-forming ability on food-contact surfaces. In this study, CAU_ECP01 is isolated, a novel strictly lytic bacteriophage specific to E. coli O157:H7, from a wastewater treatment facility in South Korea. Whole-genome sequencing of phage CAU_ECP01 revealed a double-stranded DNA genome of 169,126 bp and a 37.7% GC content. No virulence- or antibiotic resistance-related genes were detected. Phage CAU_ECP01 exhibited rapid adsorption (94% within 30 min) and remained stable over a wide range of temperature (0-60 °C) and pH (4-10). In planktonic cultures grown in LB broth at 37 °C, phage treatment at an MOI of 100 prevented detectable bacterial regrowth for 22 h, while even a low MOI of 0.1 resulted in a significant reduction in bacterial proliferation. On stainless steel and high-density polyethylene surfaces, phage CAU_ECP01 reduced pre-formed E. coli O157:H7 biofilms by 2.0 and 1.9 log CFU/cm2, respectively (P < 0.05). When applied to inoculated beef and lettuce stored at 25 °C, phage treatment (MOI 100) achieved significant reductions of 1.2 and 2.3 log CFU/g, respectively (P < 0.05). Hunter color and texture profile analysis revealed no significant differences between treated and untreated samples (P > 0.05), indicating no adverse effects on product quality. Overall, these findings demonstrate that phage CAU_ECP01 is a potent, stable, and safe biocontrol candidate capable of effectively mitigating E. coli O157:H7 contamination on food-contact surfaces, meat, and fresh produce, highlighting its potential application in modern food processing environments.
In the Philippines, most of the population relies on decentralized wastewater systems, particularly septic tanks, and the rest on centralized wastewater systems. However, the performance of wastewater treatment systems in the Philippines in reducing viral contaminants remains to be characterized; thus, in this study, the occurrence and reduction of viruses in wastewater before and after treatment were assessed at a wastewater treatment plant (WWTP) that utilizes biological treatment technologies in the Philippines. Influent (n = 18) and effluent (n = 18) samples collected from WWTP from April to August 2024 were centrifuged, followed by viral nucleic acid extraction. Cross-assembly phage (crAssphage) was quantified through quantitative polymerase chain reaction (qPCR), and pepper mild mottle virus (PMMoV), influenza A virus (Inf-A), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and norovirus genogroups I (NoV-GI) and II (NoV-GII) were quantified by reverse transcription-qPCR. All viral targets were quantified in wastewater before and after treatment, except for Inf-A and SARS-CoV-2, which were absent in all effluent samples. The reduction in viral loads in wastewater after treatment was determined, with crAssphage, PMMoV, NoV-GI, and NoV-GII showing high log10 reduction values (LRVs) of 4.35, 4.28, 4.56, and 4.00, respectively, while their lowest LRVs were 2.17, 0.38, 0.72, and − 0.99, respectively. The persistence of crAssphage and PMMoV in wastewater samples and their significant positive associations with NoV-GI and NoV-GII suggest their potential application as indicators of enteric viruses in Philippine wastewater. These findings highlight the importance of viruses in characterizing treatment plant reduction performance and water and wastewater quality in the Philippines.
Klebsiella pneumoniae strains that combine multidrug resistance and enhanced virulence pose a growing global public health threat. Understanding the genetic basis of these high-risk lineages is critical for surveillance and mitigation. We isolated K. pneumoniae JU-BAEC-01 from treated effluent of antibiotic-manufacturing pharmaceutical facilities in Bangladesh and performed whole-genome sequencing with comparative genomic analyses to characterize its phylogeny, resistome, virulence-associated loci, mobile genetic elements, and predicted antiviral defense systems. JU-BAEC-01 belongs to a phylogenetically distinct lineage, serotype O3b: KL150 with resistance to nearly all clinically relevant antibiotic classes except carbapenems and colistin, mediated by an extensive acquired resistome, including tmexCD3-toprJ3 (tigecycline), armA, aac(6')-Ib-cr, qnrB4, oqxAB, blaDHA-1, blaSHV-182, and blaTEM-1B, mostly carried on conjugative IncC, IncFIB, IncHI1B, and IncR plasmids. Classical hypervirulence markers are present: complete aerobactin (iucABCD-iutA) and salmochelin (iroBCDEN) clusters, rmpA2, type 1 and type 3 fimbriae, T6SS, and pgaABCD. Notably, the strain encodes one of the most elaborate anti-phage defense arsenals reported in Klebsiella to date, comprising functional Type I-E, III-A, and IV-A CRISPR-Cas systems, multiple restriction-modification systems, BREX Type I, abortive infection systems (AbiE, AbiU), and additional novel defenses that coexist with phage-derived anti-CRISPR (AcrIE9) and anti-restriction (ArdA) proteins. K. pneumoniae JU-BAEC-01 is a "perfect storm" pathogen that combines multi-drug resistance (MDR), hypervirulence, and a multilayered, highly developed defense against bacteriophages. Together, these findings highlight the environmental emergence of a genetically distinct, multidrug-resistant K. pneumoniae with substantial virulence potential and complex phage-host interaction capacity, underscoring the need for genomic surveillance of pharmaceutical wastewater systems.
Human Aichi virus (AiV-A1), a member of the Kobuvirus genus associated with viral gastroenteritis, remains largely underdiagnosed in Latin America due to the absence of routine testing and limited epidemiological data. This study provides the first molecular evidence of AiV-A1 circulation in Argentina to date, based on the analysis of wastewater and pediatric stool samples collected in Córdoba between 2012 and 2019. A total of 93 untreated wastewater samples from the main wastewater treatment plant and 155 stool samples from children with acute gastroenteritis (AGE) were screened using a validated nested RT-PCR targeting the 3CD region, followed by sequencing and phylogenetic analysis. AiV-A1 was detected in 58% of wastewater samples, demonstrating continuous, year-round circulation without a defined seasonal pattern. Among clinical AGE cases, AiV-A1 was identified in 21.5%, including 10.3% as monoinfections. Inclusion of AiV-A1 in the diagnostic panel within this study, increased the overall viral detection rate from 62% to 69%, suggesting that its incorporation into routine diagnostics could improve the detection of virologically confirmed diarrhea cases. Phylogenetic reconstruction showed that all Argentine strains clustered within genotype B, forming two intragenotypic lineages and exhibiting high nucleotide identity (94.8%-99.6%) between environmental and clinical isolates. Together, these findings provide the first evidence of endemic AiV-A1 circulation in Argentina, highlight its potencial role in pediatric gastroenteritis, and establish a baseline for future regional epidemiological studies while offering relevant insight into the burden, transmission, and molecular epidemiology of AiV-A1 in the country.
Increasing water scarcity and climate-related extremes are amplifying the need for safe water reuse, however, wastewater treatment plants (WWTPs) may not fully remove viral pathogens, posing potential risks to freshwater environments. This study assessed human enteric and respiratory viruses using (RT)-qPCR, along with faecal indicators using culture-based methods, at WWTPs in two Mediterranean protected areas (Albufera Natural Park and the Ebro River region) across three campaigns. A total of influent (n = 33), reclaimed wastewater (n = 33), biosolids (n = 32), surface water (n = 33), and sediment (n = 29) samples were analysed. Influent wastewater contained a wide range of viral and faecal indicators, with biosolids showing similar levels. Although reclaimed water demonstrated reductions in Escherichia coli and somatic coliphages, these reductions remained below the ≥ 5 and ≥ 6 Log10 threshold required under EU water reuse regulations, respectively. In surface waters, human enteric viruses were detected at low concentrations, with human norovirus genogroup II (HuNoV GII) showing the highest incidence (36.36%). SARS-CoV-2 was detected in 15.15% of samples, while influenza A virus (IAV) was found in only one sample. Sediments yielded viral signals in 10–35% of samples, whereas E. coli and somatic coliphages were detected in 6.9% and 10.3% of samples, respectively. Hepatitis E virus (HEV) genotype 3f exhibited a clear winter trend, whereas faecal indicators were consistently detected across matrices. In contrast, E. coli and somatic coliphages showed no correlation with viral detections. As the first comprehensive survey of viral presence in these Mediterranean systems, this study provides a baseline for monitoring and managing viral contamination risks during and after extreme climate events, which may exacerbate pathogen mobilization and dissemination. Additionally, the detection of zoonotic viruses, including IAV and HEV, highlights the value of wastewater and environmental surveillance (WES) in biodiversity-rich environments.
Pepper Mild Mottle Virus (PMMoV) is widely used in wastewater-based surveillance as a faecal indicator and population size marker. It is highly abundant in domestic wastewater and originates from the consumption ofCapsicum-containing foods. Despite its widespread use, data on the variability of PMMoV concentrations in wastewater remain limited, and its primary dietary sources are not fully characterised. To evaluate the robustness of PMMoV as a human faecal marker, we analysed wastewater from multiple locations in Sweden over different timescales, ranging from daily to weekly sampling for up to nearly three years. We also investigated dietary sources by screening a broad range of foods. Wastewater consistently contained high PMMoV levels, averaging 10.34 log10 genome copies per inhabitant per day. The average daily PMMoV load scaled almost proportionally with the number of inhabitants connected to each catchment area. No clear temporal trends were detected over either short or long time periods, and no substantial associations were found with potentially influencing factors such as demographic or socioeconomic characteristics of the catchment population, season, wastewater temperature or weekday. Of 60 foods tested, 45 contained PMMoV, with concentrations ranging from 5.70 to 12.21 log10 genome copies per serving. The highest levels were found in spices, such as paprika powder, as well as in ready meals, spreads and snack products. These widely consumed foods likely contribute to the consistently high PMMoV levels observed in domestic wastewater. Taken together, our findings support the potential of PMMoV as a robust and broadly applicable human faecal marker.
Hepatitis A (HepA) is a viral hepatitis caused by the hepatitis A virus (HAV), and currently Mexico is considered to have an intermediate-HAV endemicity. Wastewater-based epidemiology (WBE) is a tool for monitoring infectious diseases but has been poorly evaluated in intermediate-HAV-endemicity settings. From June 2024 to June 2025, 24-hour composite wastewater samples were collected twice a week from three wastewater treatment plants in the metropolitan area of San Luis Potosí, Mexico. Wastewater samples were ultracentrifuged, RNA was extracted, and HAV and crAssphage (for normalization) were detected by qPCR and weighted by the wastewater treatment plant's inflow. We compared these results with HepA hospital admissions from eight public hospitals in the city during the same period. We compared HAV genotype sequences obtained from wastewater and patients. We processed 244 wastewater samples over 46 weeks, of which 35.1% tested positive for HAV. Seventy-three HepA hospital admissions were reported during this period. The Spearman correlation between HAV viral load and hospital admissions, along with its displacement over 10 weeks, showed the strongest correlation between Lag 4 to Lag 6. We genotyped six HAV strains from wastewater samples and two from HepA patients. Phylogenetic analysis revealed that the patient strains were distinct but identical or closely related to the circulating wastewater strains. In conclusion, WBE HAV surveillance may predict an increase in HepA admissions four to six weeks in advance. Diverse, but closely related HAV strains constantly circulate in intermediate HAV-endemicity settings.
Pepper mild mottle virus (PMMoV) has emerged as a promising viral indicator for human fecal contamination and evaluating viral removal efficiency in water treatment systems. However, few studies have examined this potential from a genetic perspective over extended timescales. This study investigated PMMoV presence and genetic diversity across multiple water environments in Sweden, including wastewater, lake water, and raw water used for drinking water production, collected between 2016 and 2024. PMMoV was consistently detected in both wastewater and lake water, showing relatively stable concentrations in wastewater between years, and with levels typically 4-7 log₁₀ higher than in lake water. Comparative genotyping of the coat protein (CP) and replication-associated (RP) regions for wastewater samples showed no significant differences. We successfully sequenced 67 isolates from wastewater, 16 from lake water, and 2 from source water at the CP region. Sequence analysis revealed extremely high nucleotide identities (> 96%) with minimal divergence between samples collected six years apart or from different water types. Phylogenetic comparisons with global reference sequences confirmed high genetic conservation worldwide. These findings demonstrate the remarkable genetic stability of PMMoV over time and geography, supporting its reliability as a viral process indicator for water treatment systems. However, the potential for PMMoV to originate from non-human sources suggests it should not be used as a standalone marker for human-specific fecal contamination. Overall, this study highlights the global genetic conservation of PMMoV and its utility for long-term environmental surveillance and water quality assessment.
Antibiotic-resistant Enterococcus faecalis and E. faecium are persistent contaminants in food and environmental settings, including poultry-related matrices, contributing to food safety risks and antimicrobial resistance (AMR) dissemination. This study aimed to identify Enterococcus phages through environmental screening and evaluate their biocontrol potential using a chicken wing food model. From 1719 environmental samples, 45 Enterococcus-targeting phages were isolated, and two (Efs.1 1-1 and Efm 3-10) with the broadest lytic profiles were selected for characterization. Transmission electron microscopy revealed that both phages belong to Caudoviricetes with siphovirus-like morphology, latent periods (6-8 min), and high burst sizes (90-110 PFU per cell). Whole-genome sequencing revealed complete circular genomes with estimated completeness values between 0.97 and 1.00, and no detectable virulence, lysogeny, or AMR genes. The phages were stable at pH 4 for 60 min and tolerated 40-60 °C for 1 h. Phage titers decreased from 10.0 to no less than 6.0 log PFU mL-1 across all storage conditions over 12 months. In vitro assays in tryptic soy broth showed that while the control groups reached 8.56-9.12 log CFU mL-1 at 24 h at 37 °C, no bacteria were detected in any of the phage-treated samples (limit of detection: 1 CFU mL-1). In the chicken wing food model, phage treatment maintained bacterial counts below the detection limit (<1 log CFU g-1) throughout refrigerated storage. Mean log reductions reached 1.78-2.78 and 3.71-4.71 log CFU g-1, respectively. These novel lytic phages exhibit strong stability and rapid antibacterial activity, offering promising biocontrol agents to reduce Enterococcus contamination in chicken meat. © 2026 Society of Chemical Industry.
BACKGROUND: Acinetobacter baumannii, is a WHO-recognized critical pathogen, poses a severe clinical threat due to multidrug resistance, environmental persistence and a robust biofilm formation. The rapid failure of conventional antibiotics necessitates alternative strategies, with bacteriophage therapy emerging as a promising, targeted, and eco-friendly approach. METHODS AND RESULTS: In this study, a lytic bacteriophage, designated TANUVAS_MVC-VPH-AB, was isolated and characterized for its activity against Acinetobacter spp. Morphological and genomic analyses classified the phage within the class Caudoviricetes, possessing a linear double-stranded DNA genome of 45 kb and a GC content of 37.61%. Genome annotation identified 93 putative genes, with no virulence-associated genes and antibiotic resistance determinants supporting its safety as a potential therapeutic agent. The phage demonstrated strong lytic activity and a restricted yet polyvalent host range within the A. calcoaceticus - A. baumannii complex, along with detectable stability across the tested pH and temperature conditions. Additionally, it demonstrated potent biofilm inhibition and eradication on abiotic surfaces (polystyrene). CONCLUSION: These findings suggest that TANUVAS_MVC-VPH-AB is a promising candidate for bacteriophage therapy, offering a viable alternative to combat MDR A. baumannii infections, particularly in biofilm-associated environments within hospital and food related settings.
Bacillus cereus is a major foodborne pathogen responsible for food spoilage and foodborne illness, including strains producing emetic toxins. In this study, two bacteriophages, PBC_MG88 and PBC_MG99, were isolated from wastewater using emetic B. cereus strains as hosts and were comprehensively characterized. Both phages formed clear plaques with halos and exhibited siphovirus morphology. Host range analysis against 172 B. cereus strains showed that PBC_MG88 and PBC_MG99 infected 50 and 60 strains, respectively. One-step growth experiments revealed efficient lytic activity, with latent periods of 20-25 min and burst sizes of 59-63 PFU per infected cell. More than 90% of phage particles adsorbed to host cells within 15 min. Both phages were stable across a wide temperature range (4-55 °C) and pH values (4-11). Genome sequencing revealed ~37 kb double-stranded DNA genomes lacking antibiotic resistance or virulence genes; however, the presence of lysogeny-related genes suggests a temperate lifestyle. Comparative genomic analyses indicated that both phages represent novel species within the genus Lwoffvirus. Biofilm assays demonstrated significant inhibition of B. cereus biofilm formation and reduction of pre-established biofilms. Overall, this study expands knowledge of B. cereus phage diversity and highlights the importance of genomic characterization in phage-based biocontrol research.
Enterobacter hormaechei (E. hormaechei) is an opportunistic pathogen in poultry, increasingly associated with multidrug resistance due to the extensive use of antibiotics in animal production. The emergence of resistant E. hormaechei strains poses a significant threat to poultry health and food safety, highlighting the urgent need for alternative antimicrobial strategies. This study aimed to isolate and characterize a novel lytic bacteriophage targeting E. hormaechei and to evaluate its biological properties and therapeutic potential in a gastrointestinal infection mice model. A lytic phage, designated S18-3, was isolated from environmental water using E. hormaechei strain HZW1 isolated from diseased broiler liver. Phage S18-3 forms clear plaques (~ 0.6 cm) and exhibits an icosahedral head with a long tail. Optimal infectivity occurs at an MOI of 0.1. S18-3 remains stable from 30 to 50 °C and tolerates a broad pH range (pH 4-11). Whole-genome sequencing revealed no known virulence factors or antimicrobial resistance genes, indicating favorable genetic safety. In a murine intestinal infection model established by antibiotic pretreatment and oral challenge, E. hormaechei caused significant weight loss and mortality. Oral administration of S18-3 markedly improved survival and mitigated weight loss compared with infected controls. Phage S18-3 titers were detectable in feces in infection group, with only transient, low-level presence in blood. Histopathology showed no evident liver injury or inflammatory changes, suggesting no hepatotoxicity associated with phage treatment. Phage S18-3 is a stable, genetically safe lytic phage that effectively alleviates intestinal E. hormaechei infection in a murine model without observable adverse effects. These data support the potential of S18-3 as an antibiotic alternative for controlling E. hormaechei infections in poultry. Further validation in broiler models and farm-level settings is warranted to assess translational applicability in sustainable poultry production.