Timely detection of highly infectious pathogens is essential for preventing and controlling public health risks. However, most traditional testing instruments require multiple tedious steps and ultimately testing in hospitals and third-party laboratories. The sample transfer process significantly prolongs the time to obtain test results. To tackle this aspect, a portable fiber optic surface plasmon resonance (FO-SPR) device was developed for the real-time detection of infectious pathogens. The portable device innovatively integrated a compact FO-SPR sensing component, a signal acquisition and processing system, and an embedded power supply unit. A gold-plated fiber is used as the FO-SPR sensing probe. Compared with traditional SPR sensing systems, the device is smaller size, lighter weight, and higher convenience. To enhance the detection capacity of pathogens, a monolayer graphene was coated on the sensing region of the FO-SPR sensing probe. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was used to evaluate the performance of the portable device. The device can accurately detect the SARS-CoV-2 spike S1 protein in phosphate-buffered saline (PBS) and artificial saliva within just 20 min, and the device successfully detected cultured SARS-CoV-2 virus. Furthermore, the FO-SPR probe has long-term stability, remaining stable for up to 8 days. It could distinguish between the SARS-CoV-2 spike protein and the MERS-CoV spike protein. Hence, this FO-SPR device provides reliable, rapid, and portable access to test results. It provides a promising point-of-care testing (POCT) tool for on-site screening of infectious pathogens.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as the prime challenge facing public health safety since 2019. Correspondingly, coronavirus disease 2019 (COVID-19) vaccines have been developed and administered worldwide, varying in design strategies, delivery routes, immunogenicity and protective efficacy. Here, a replication-competent vesicular stomatitis virus (VSV) vectored recombinant COVID-19 vaccine was constructed and evaluated in BALB/c mice and Syrian golden hamsters. In BALB/c mice, intramuscular (i.m.) inoculation of recombinant vaccine induced significantly higher humoral immune response than that of the intranasal (i.n.) inoculation group. Analyses of cellular immunity revealed that a Th1-biased cellular immune response was induced in i.n. inoculation group while both Th1 and Th2 T cells were activated in i.m. inoculation group. In golden hamsters, i.n. inoculation of the recombinant vaccine triggered robust humoral immune response and conferred prominent protective efficacy post-SARS-CoV-2 challenge, indicating a better protective immunity in the i.n. inoculation group than that of the i.m. inoculation group. This study provides an effective i.n.-delivered recombinant COVID-19 vaccine candidate and elucidates a route-dependent manner of this vaccine candidate in two most frequently applied small animal models. Moreover, the golden hamster is presented as an economical and convenient small animal model that precisely reflects the immune response and protective efficacy induced by replication-competent COVID-19 vaccine candidates in other SARS-CoV-2 susceptible animals and human beings, especially in the exploration of i.n. immunization.

Hebei Province is an important area for breeding broiler chickens in China, but the antimicrobial resistance and prevalence of Escherichia coli (E. coli) are still unclear. A total of 180 cloacal samples from broiler farms in Hebei Province were collected and used for the isolation and identification of E. coli. The isolates were subjected to resistance phenotyping, resistance profiling, and genotyping, and some multiresistant strains were subjected to multilocus sequence typing (MLST). The results showed that 175 strains were isolated. Among both types of broiler farms, the ampicillin resistance rate was the highest, and the meropenem resistance rate was the lowest. Serious multiresistance was present in both types of broiler farms. Thirty strains of multidrug-resistant E. coli were typed by MLST to obtain a total of 18 ST types, with ST10 being the most prevalent. This study was to simply analyze the antimicrobial resistance and prevalence of E. coli in broiler chickens in Hebei Province after the implementation of the pilot work program of action to reduce the use of veterinary antimicrobials in standard farms (SFs) and nonstandard farms (NSFs). This study will provide a research basis and data support for the prevention and control of E. coli in Hebei.

Lentinan (LNT) was found to reduce the aerosol transmission rate between golden hamsters from 100% (9/9) to 44.4% (4/9). The viral loads in the respiratory system, including the nasal turbinate, trachea, and lung, were significantly reduced in the infected golden hamsters that received LNT treatment. Furthermore, the amount of exhaled virus aerosols in hamsters treated with LNT was significantly lower than that in untreated hamsters throughout the entire disease progression. In detail, the amounts of virus-laden particles with aerodynamic diameters less than 5 µm exhibited a significant decreasing trend following LNT treatment. Moreover, the detection rate of infectious SARS-CoV-2 in each stage of the Anderson-6 sampler exhibited a decreasing trend following LNT treatment post-infection. In summary, our findings indicate that LNT therapy represents a promising therapeutic candidate for the treatment of COVID-19 patients. Meanwhile, during the course of treatment, LNT has the potential to reduce viral infectivity in affected individuals.

Avian influenza viruses (AIVs) pose a significant zoonotic threat, with the emerging H3N8 subtype raising increasing concern due to sporadic human infections. Current strategies for risk assessment of novel AIVs primarily rely on genetic surveillance and isolated case reports, which provide limited insight into their cross-species transmission potential. However, these approaches may overlook critical phenotypic determinants, such as pathogenicity, transmissibility, and environmental persistence, that directly influence zoonotic risk. This study investigates the evolutionary relationships, receptor-binding properties, replication dynamics, pathogenicity in mice, transmission efficiency in guinea pigs, and environmental persistence of three H3N8 strains isolated from a live poultry market. All three H3N8 strains bound exclusively to α-2,3 sialic acid receptor and achieved 100% transmissibility among guinea pigs through direct contact. Notably, the environment-origin strain A09 exhibited an indirect contact transmission efficiency of 33.3%. The findings reveal strain-specific differences, with A09 displaying enhanced pathogenicity, broader transmission routes, and greater environmental persistence compared with A05 and A01. This perspective underscores the value of integrated profiling from genotype to phenotype combined with multi-route transmission and environmental persistence analyses to delineate the adaptive roadmap of H3N8 from avian to mammalian hosts and to assess its emerging infection risk. Future directions for surveillance and intervention were also discussed, highlighting their potential to strengthen preparedness against zoonotic influenza threats.

The H7N9 influenza viruses, which are capable of causing severe respiratory syndrome in humans, were first discovered to infect humans in 2013 and continue to pose a persistent public health threat. Quail has been proposed as a potential intermediate host that may facilitate the emergence of novel reassorted influenza A viruses with the capacity to infect humans across species barriers; however, information on the biological characterization of quail H7N9 remains limited. In this study, we isolated and identified an avian H7N9 influenza virus from quails, designated as A/quail/Hebei/CH06-07/2018 (H7N9) and abbreviated as CH06-07, in Hebei, China. Phylogenetic analyses revealed that both the HA gene and the NA gene of CH06-07 were clustered in the Eurasian lineage. Furthermore, CH06-07 exhibited binding affinity for both α2,3-linked and α2,6-linked sialic acid receptors and demonstrated high pathogenicity in both quails and mice. Notably, transmission studies revealed that CH06-07 not only exhibited efficient inter-quail transmission and inter-guinea pig transmission but also demonstrated effective cross-species transmission. Importantly, infected quails and guinea pigs generated significant quantities of viral aerosols (≥18,998 ± 1672 copies per liter of air at 3 days post-infection), and infectious viruses were successfully recovered from environmental aerosols. These findings highlight the necessity for continuous surveillance of the prevalence of quail-origin H7N9 influenza A viruses in poultry populations due to their potential threat to human health.