Front Vet Sci. 2025 Mar 5;12:1495128. doi: 10.3389/fvets.2025.1495128. eCollection 2025.
ABSTRACT
INTRODUCTION: Porcine Reproductive and Respiratory Syndrome (PRRS) is a highly contagious disease that causes reproductive disorders in sows and respiratory problems in pigs of different ages. It first appeared in the late 20th century in the United States and Europe before spreading globally, leading to significant economic losses in the swine industry. Porcine Reproductive and Respiratory Syndrome virus (PRRSV) has a high rate of genetic recombination, resulting in considerable genetic diversity within the virus. The lack of cross-protection between different lineages often leads to unsuccessful vaccination attempts.
METHODS: To accurately distinguish PRRSV lineages and develop effective vaccination strategies for pigs, we have developed a fluorescence quantitative PCR (qPCR) method by designing specific primers and SYBR green dye. This method allows for the simultaneous identification of different PRRSV genotypes.
RESULTS: Our experimental results show that these methods have good specificity and do not react with other common viral pathogens in pigs. This method also demonstrates good sensitivity, with the ability to detect low levels of the virus. The detection limits of these assay were 102 copies/μL for PRRSV-1 (European-type PRRS) and 101 copies/μL for PRRSV-2 (American-type PRRSV), HP-PRRSV (Highly Pathogenic PRRSV), and NL-PRRSV (NADC30-like PRRSV), respectively. Furthermore, the reproducibility of this method is commendable, with intra- and inter-assay coefficients of variation remaining below 3%. In the subsequent study, a total of 316 clinical samples of porcine with respiratory and reproductive failure symptoms were collected from 14 cities in Guangdong. The results showed that among these samples, 22.78% (72 out of 316) tested positive for PRRSV-2, 15.51% (49 out of 316) tested positive for HP-PRRSV, and 0.95% (3 out of 316) tested positive for NL-PRRSV. However, PRRSV-1 was not detected in any of the samples.
DISCUSSION: Our method provides a quick way to identify PRRSV genotypes in pig herds in Guangdong, which has certain significance for developing effective vaccination strategies against PRRS.
PMID:40110430 | PMC:PMC11921047 | DOI:10.3389/fvets.2025.1495128
Front Vet Sci. 2025 Feb 27;11:1472658. doi: 10.3389/fvets.2024.1472658. eCollection 2024.
ABSTRACT
INTRODUCTION: Hepatitis E virus (HEV) is a major cause of acute hepatitis in humans and recognized as a zoonotic pathogen, with swine serving as a primary reservoir. Despite substantial research, comprehensive analysis encompassing regional variations and pig growth stages within China, as well as the influence of recent biosecurity measures on HEV prevalence, remains limited. In this study, we aim to assess the prevalence and risk factors associated with swine HEV in China.
METHODS: A thorough review of HEV infection studies was conducted using six databases: China National Knowledge Infrastructure, Wanfang, Wipro, Centre for Agriculture and Biosciences International, PubMed, and ScienceDirect, covering publications from January 1, 2004 to December 31, 2023. Eighty-seven studies investigating the seroprevalence of swine HEV IgG antibodies and HEV RNA detection rates were included. A rigorous meta-analysis and quality assessment followed.
RESULTS: The combined seroprevalence of swine HEV IgG antibodies was 58.0% (95% confidence interval [CI]: 52.0-65.0). The seroprevalence from 2019 to 2023 was lower (27.4, 95% CI: 26.3-28.2) than that in other years. The seroprevalence was higher in sows (67.2, 95% CI: 55.8-78.7) than in suckling, nursery, and fattening pigs. The detection rate of HEV RNA was 13.0% (95% CI: 11.0-15.0), with fattening pigs showing a significantly higher positivity rate (16.9, 95% CI: 13.2-20.7) than sows and suckling pigs. HEV RNA detection was significantly lower in bile (8.3, 95% CI: 6.3-10.3) than in feces and liver.
DISCUSSION: This study highlights the widespread presence of HEV in pig farms across China, with prevalence strongly linked to pig growth stage, study year, and sample type. The findings underscore the importance of pig growth stage, sample type, and recent biosecurity measures in controlling HEV prevalence, providing actionable insights for improving biosecurity practices in pig farms.
PMID:40084118 | PMC:PMC11905393 | DOI:10.3389/fvets.2024.1472658
Molecules. 2025 Feb 8;30(4):790. doi: 10.3390/molecules30040790.
ABSTRACT
Avian coccidiosis, caused by protozoan parasites of the genus Eimeria, poses a major threat to the poultry industry worldwide, leading to severe economic losses through reduced growth rates, poor feed efficiency, and increased mortality. Although the conventional management of this disease has relied on anticoccidial drugs, the overwhelming use of these agents has led to the rapid emergence and spread of drug-resistant Eimeria isolates, highlighting the urgent need for novel therapeutic approaches. This study employed computational approaches to identify novel inhibitors targeting Eimeria tenella prolyl-tRNA synthetase (EtPRS). Based on the virtual screening of a library of 3045 natural compounds, 42 high-confidence inhibitors were identified. Three compounds, including Chelidonine, Bicuculline, and Guggulsterone, demonstrated strong and selective binding to EtPRS through stable interactions within the active site. ADMET predictions revealed favorable safety profiles, while molecular dynamic simulations confirmed binding stability. Overall, this research established a solid framework for the development of effective anticoccidial agents targeting PRS, contributing to the advancement of therapeutic strategies for combating parasitic infections in the poultry industry.
PMID:40005102 | PMC:PMC11858595 | DOI:10.3390/molecules30040790
Sci China Life Sci. 2025 Feb 20. doi: 10.1007/s11427-024-2856-y. Online ahead of print.
ABSTRACT
Identification of host factors that play a key role in viral replication is of great importance for antiviral development. Metabotropic glutamate receptor subtype 2 (mGluR2) is the receptor to trigger clathrin-mediated endocytosis (CME), the major pathway by which influenza virus enters cells. However, other host factors almost certainly involved in the influenza virus CME are largely unknown. Here, we found that the four-transmembrane protein claudin-11 plays an integral part in influenza virus CME. Claudin-11 promotes the dissociation of KCa1.1 (potassium calcium-activated channel subfamily M alpha 1) from mGluR2 and, together with mGluR2, is internalized in virus-containing clathrin-coated pits (CCPs), where it regulates the depolymerization of polymerized F-actin, allowing the CCPs to mature. Importantly, over 60% of claudin-11-silenced mice survived infection with a lethal influenza virus. Our findings advance the understanding of influenza virus infection and provide a promising strategy for the development of host-based antiviral drugs.
PMID:39985647 | DOI:10.1007/s11427-024-2856-y
Lancet Infect Dis. 2025 Feb 17:S1473-3099(25)00068-4. doi: 10.1016/S1473-3099(25)00068-4. Online ahead of print.
NO ABSTRACT
PMID:39978373 | DOI:10.1016/S1473-3099(25)00068-4
BMC Vet Res. 2025 Feb 12;21(1):62. doi: 10.1186/s12917-025-04508-2.
ABSTRACT
BACKGROUND: Infectious diseases including Newcastle disease (ND) impair poultry productivity and represent a significant burden to sustainable agriculture in Nigeria. This study aimed to investigate the active circulation and seroprevalence of Newcastle disease virus (NDV) caused by virulent forms of avian paramyxovirus type-1 (APMV-1) in poultry at live bird markets (LBMs) across Nigeria.
METHODS: A cross-sectional study of 18 LBMs was conducted within three states in Nigeria (Kano, Oyo, and Abuja). Paired swab and tissue samples (n = 413) were collected from birds on FTA cards and tested for APMV-1 using real-time reverse transcription polymerase chain reaction (rRT-PCR). A subset of rRT-PCR-positive samples were selected for whole genome sequencing based on the originating species (chicken, duck, geese), date, and market location to provide a broad range of isolates for characterisation. Blood samples (n = 405) were also collected from birds and the seroprevalence of APMV-1 antibodies was measured using an enzyme-linked immunosorbent assay (ELISA).
RESULTS: APMV-1 RNA was detected in 21.5% (89/413) of samples from LBMs by rRT-PCR. At least one APMV-1 positive sample was detected in 55.6% (10/18) of LBMs. The largest proportion of APMV-1-positive markets was in Kano (83.3%, 5/6), whereas the lowest was in Oyo (16.7%, 1/6). Assessment of genetic data demonstrated that genotype XIV.2 APMV-1 was circulating within Nigeria with the viruses detected clustering closely with other Nigerian isolates described previously. The seroprevalence of APMV-1 in birds was 45.9% (186/405) and 94.4% (17/18) of LBMs had at least one APMV-1 seropositive sample (i.e., with at least one APMV-1-antibody-positive bird). The LBMs in Kano had the lowest seroprevalence (88.3%, 5/6).
CONCLUSIONS: This study demonstrated that APMV-1 continues to circulate in LBMs in Nigeria. LBM traders, poultry producers, and related industry and policy stakeholders should be aware of the occurrence of APMV-1 and how ND may negatively impact upon poultry production and the livelihoods of poultry farmers and LBM traders. Training initiatives aimed at improving the knowledge of APMV-1 infection and improvements in biosecurity practises and the role of disease mitigation through vaccination are required to reduce the impact of this threat to food security.
PMID:39939962 | PMC:PMC11817539 | DOI:10.1186/s12917-025-04508-2
Nat Commun. 2025 Jan 20;16(1):861. doi: 10.1038/s41467-024-55737-2.
ABSTRACT
The World Health Organization describes brucellosis as one of the world's leading zoonotic diseases, with the Middle East a global hotspot. Brucella melitensis is endemic among livestock populations in the region, with zoonotic transmission occurring via consumption of raw milk, amongst other routes. Control is largely via vaccination of small ruminant and cattle populations. Due to sociocultural and religious influences camel milk (camelus dromedarius) is widely consumed raw, while milk from other livestock species is largely boiled. To investigate the potential public health impact of Brucella in camels we conduct a cross-sectional study in southern Jordan including 227 herds and 202 livestock-owning households. Here we show daily consumption of raw camel milk is associated with Brucella seropositive status among the study population, ORadj 2.19 (95%CI 1.23-3.94) on multivariable analysis, highlighting the need for socioculturally appropriate control measures; targeted interventions among the camel reservoir being crucial for effective control.
PMID:39833143 | PMC:PMC11756418 | DOI:10.1038/s41467-024-55737-2
Adv Sci (Weinh). 2025 Mar;12(9):e2414651. doi: 10.1002/advs.202414651. Epub 2025 Jan 10.
ABSTRACT
To bolster the capacity for managing potential infectious diseases in the future, it is critical to develop specific antiviral drugs that can be rapidly designed and delivered precisely. Herein, a CRISPR/Cas13d system for broad-spectrum targeting of influenza A virus (IAV) from human, avian, and swine sources is designed, incorporating Cas13d mRNA and a tandem CRISPR RNA (crRNA) specific for the highly conserved regions of viral polymerase acidic (PA), nucleoprotein (NP), and matrix (M) gene segments, respectively. Given that the virus targets cells with specific receptors but is not limited to a single organ, a Susceptible Cell Selective Delivery (SCSD) system is developed by modifying a lipid nanoparticle with a peptide mimicking the function of the hemagglutinin of influenza virus to target sialic acid receptors. The SCSD system can precisely deliver an all-RNA-based CRISPR/Cas13d system into potentially infected cells. This drug is shown to reduce the viral load in the lungs by 2.37 log10 TCID50 mL-1 and protect 100% of mice from lethal influenza infection. The SCSD-based CRISPR/Cas13d system shows promise for the flexible and efficient therapy of infections caused by rapidly evolving and novel viruses.
PMID:39792803 | PMC:PMC11884569 | DOI:10.1002/advs.202414651
Nat Commun. 2025 Jan 9;16(1):432. doi: 10.1038/s41467-024-55193-y.
ABSTRACT
Influenza remains a persistent global health challenge, largely due to the virus' continuous antigenic drift and occasional shift, which impede the development of a universal vaccine. To address this, the identification of broadly neutralizing antibodies and their epitopes is crucial. Nanobodies, with their unique characteristics and binding capacity, offer a promising avenue to identify such epitopes. Here, we isolate and purify a hemagglutinin (HA)-specific nanobody that recognizes an H7 subtype of influenza A virus. The nanobody, named E10, exhibits broad-spectrum binding, cross-group neutralization and in vivo protection across various influenza A subtypes. Through phage display and in vitro characterization, we demonstrate that E10 specifically targets an epitope on HA head which is part of the conserved lateral patch and is highly immunodominant upon H7 infection. Importantly, immunization with a peptide including the E10 epitope elicits cross-reactive antibodies and mediates partial protection from lethal viral challenge. Our data highlights the potential of E10 and its associated epitope as a candidate for future influenza prevention strategies.
PMID:39788944 | PMC:PMC11718266 | DOI:10.1038/s41467-024-55193-y
PLoS Biol. 2024 Nov 12;22(11):e3002916. doi: 10.1371/journal.pbio.3002916. eCollection 2024 Nov.
ABSTRACT
H5 influenza is considered a potential pandemic threat. Recently, H5 viruses belonging to clade 2.3.4.4b have caused large outbreaks in avian and multiple nonhuman mammalian species. Previous studies have identified molecular phenotypes of the viral hemagglutinin (HA) protein that contribute to pandemic potential in humans, including cell entry, receptor preference, HA stability, and reduced neutralization by polyclonal sera. However, prior experimental work has only measured how these phenotypes are affected by a handful of the >10,000 different possible amino-acid mutations to HA. Here, we use pseudovirus deep mutational scanning to measure how all mutations to a 2.3.4.4b H5 HA affect each phenotype. We identify mutations that allow HA to better bind α2-6-linked sialic acids and show that some viruses already carry mutations that stabilize HA. We also measure how all HA mutations affect neutralization by sera from mice and ferrets vaccinated against or infected with 2.3.4.4b H5 viruses. These antigenic maps enable rapid assessment of when new viral strains have acquired mutations that may create mismatches with candidate vaccine virus, and we show that a mutation present in some recent H5 HAs causes a large antigenic change. Overall, the systematic nature of deep mutational scanning combined with the safety of pseudoviruses enables comprehensive measurements of the phenotypic effects of mutations that can inform real-time interpretation of viral variation observed during surveillance of H5 influenza.
PMID:39531474 | PMC:PMC11584116 | DOI:10.1371/journal.pbio.3002916
