Biosafety and Health最新文献

Hand, foot, and mouth disease (HFMD) is a contagious disease mainly occurring in young children, and outbreaks commonly occur among young children in the Asia–Pacific region including Thailand. Moreover, the World Health Organization (WHO) monitors HFMD in the Western Pacific region to detect outbreaks and other significant events by the Regional Event Based Surveillance System. HFMD is mainly caused by a group of enteroviruses (EVs) transmitted through direct contact (person to person) and indirect contact with contaminated objects (surface-to-hand). However, few studies have examined the surface stability of EVs. In this study, we investigated the stability of enterovirus A71 (EV-A71) and coxsackievirus A16 (CVA16) on three different dry surfaces (wood, plastic, and stainless steel) using the endpoint titration using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) staining of viable cells and real-time polymerase chain reaction (viral genome detection). The results revealed that virus infectivity dramatically decreased within a few hours on dry surfaces. However, viral RNA could be detected on dry surfaces for up to 28 days. Concerning heat inactivation, both EV-A71 and CVA16 were inactivated after exposure to 60°C for 15 min. Information on virus stability on different dry surfaces will provide useful information for HFMD transmission control.

In June 2023, the 2022 global mpox (monkeypox) outbreak began to affect Guangdong Province, one of the first regions in mainland China to report mpox cases. By July 10, 2023, 93 mpox cases had been reported in Guangdong Province. This study describes the epidemiological characteristics of these patients by collecting and analyzing data on demographics, sexual behavior, medical history, travel history, clinical symptoms, and diagnostic pathways and processes. The 93 mpox cases were all men aged 20-48 years, 95.70 % were men who have sex with men (MSM), and 48.39 % were HIV-positive. A few cases were married (to women) or living with children. The rash was present in almost all cases (98.91 %), with the most common sites being the genital and perianal areas (70.33 %). Intimate sexual contact was suspected to be the main route of infection, with a median incubation period of 8.5 days (IQR 5.0–11.8). The number of cases increased rapidly, and most patients had no history of international travel, suggesting sustained community transmission within the MSM population in Guangdong Province. In addition, 93.55 % of cases were detected by medical institutions, and more than half of these patients had two or more hospital visits before being diagnosed as an mpox case, indicating that clinicians need further training to increase their sensitivity to mpox. Targeted interventions should prioritize MSM while remaining vigilant for transmission to other populations, such as women and children.

In October 2017, a small outbreak of echovirus 30 (E30) associated with aseptic meningitis in nine cases occurred at a primary school in the Ningxia Hui Autonomous Region. That year, we observed a significant increase in E30 levels in an acute flaccid paralysis (AFP) case surveillance system. To investigate their phylogenetic relationships, we determined the whole genomic sequences of 12 strains isolated from aseptic meningitis cases, AFP cases, and healthy children. We found that the E30 strains circulating in Ningxia belong to two lineages (H and J). The strains isolated in 2010, 2012, and 2016 belonged to the H lineage. In 2017, a new lineage, J, emerged as the dominant lineage. Phylogenetic trees were constructed based on the whole genome and P1, P2, and P3 regions; clustering with other types of enterovirus species B was found, suggesting that recombination events had occurred. The recombination sites were mainly in regions 2B, 2C, and 3D. This study confirmed that the E30 strains in Ningxia in 2010, 2012, and 2016 had different recombination patterns and were recombined with different enteroviruses. The 2017 epidemic E30 originated from another new lineage with a complex recombination pattern and formed an independent transmission chain in Ningxia.

To develop a national reference panel for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen detection kit and establish a quality standard. The cultures of SARS-CoV-2 and other pathogens were collected to establish a national reference panel for SARS-CoV-2 antigen detection. The stability and homogeneity of the reference panel were evaluated. Based on World Health Organization (WHO) guidance and nucleic acid quantitative results, a quality standard reference panel was established. Currently, three generations of SARS-CoV-2 antigen national reference materials with batch numbers 370095–202001, 370095–202202, and 370095–202203 have been successfully established. These national reference panels comprised 8 positive samples, 20 negative samples, 1 repetitive sample, and 1 lower detection limit sample. The stability and homogeneity of the reference panel meet the requirements. The quality standards are as follows: the positive and negative coincidence rates are 8/8 and 20/20, respectively. The 10 test results of the medium and low-concentration repetitive reference materials should be positive, and the color rendering should be uniform (or the coefficient of variance should not be higher than 20.0%). The lower detection limit should be at least 5 × 10⁵ U/mL (equivalent to copies/mL), and higher concentrations above the lower detection limit must be positive. A national reference panel for the SARS-CoV-2 antigen detection kit has been established. As the standard of SARS-CoV-2 antigen reagents, the reference panel has played a crucial role in the pre-marketing quality evaluation and post-marketing quality supervision in China.

The coronavirus disease 2019 (COVID-19) pandemic is the third human disease outbreak caused by an emerging coronavirus in the 21st century. Caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the COVID-19 pandemic has been the most devastating, with millions of deaths. Medical countermeasures are needed to limit the number of infections and fatalities. Here, we discuss advances in clinical and research-based treatment methods for SARS-CoV-2 that were initially derived from treatments for other coronaviruses. Recent advances in SARS-CoV-2 treatments, from traditional drugs and immunotherapies to artificial intelligence to predict potential future treatment methods, are summarized and discussed.

Infection with the Hantaan virus (HTNV) may result in severe hemorrhagic fever with renal syndrome (HFRS). The functions of HLA-E-restricted CD8⁺ T lymphocytes in virus control and vaccine development have recently received increased attention. The purpose of this research is to discover HLA-E-restricted CD8⁺ T cell epitopes on HTNV as well as the features of these epitope-specific CD8⁺ T cells in HFRS patients. To anticipate HLA-E-restricted HTNV epitopes, the NetMHCpan servers were utilized. The K562/HLA-E cell binding test and the enzyme-linked immunospot assay were used to confirm epitope binding to HLA-E. The number and features of HLA-E-restricted epitope-specific CD8⁺ T lymphocytes in HFRS patients were investigated using tetramer staining, intracellular cytokine labeling, proliferation, and cytotoxicity assays. Six HTNV-derived HLA-E-restricted CD8⁺ T cell epitopes were found in this study. In mild/moderate HFRS patients, the frequency of HLA-E-restricted epitope-specific CD8⁺ T cells was greater than in severe/critical patients. CD38⁺HLA-DR⁺ HLA-E-restricted CD8⁺ T cells were identified. Meanwhile, CD45RA⁺CCR7⁻ effector memory-re-expressing CD45RA T cells with early and intermediate maturation and differentiation characteristics predominated. Notably, CD8⁺ T cells from milder HFRS patients produced more interferon-γ, interleukin-2, and granzyme B, had a stronger proliferative potential, and were inversely linked with the amount of plasma HTNV virus load. Furthermore, HLA-E-restricted epitope-specific CD8⁺ T cells demonstrated improved cytotoxic activity in vitro during the acute stage of HFRS. Taken together, the findings demonstrate the protective effects of HLA-E-restricted CD8⁺ T cells during HTNV infection, suggesting that HLA-E-targeted vaccines against HTNV might be developed for HLA-diverse populations.

This paper comprehensively analyses the first-ever monkeypox outbreak in Shenzhen, China, encompassing clinical symptomatology, therapeutic approaches, epidemiological research, and comprehensive laboratory tests, aiming to establish a robust reference for future monkeypox mitigation and management strategies. The investigation involved a thorough investigation of all identified positive cases, including extensive molecular analysis by nucleic acid detection and whole-genome sequencing of the monkeypox virus. Contact tracing and containment of the infected individuals were also undertaken. Three distinct monkeypox cases were identified in this unique outbreak, exhibiting mild and atypical clinical manifestations, primarily fever and rash. All cases were associated with a single transmission chain, primarily facilitated through close contact and homosexual behavior, indicative of a high-risk factor for monkeypox transmission.

The monkeypox (mpox) virus has caused worldwide transmission since its initial report in England in early May 2022. Available data from the World Health Organization (WHO) show that Europe and the Americas experienced a huge wave of mpox virus infection. Now the number of infected cases is on the rise in Asia. Several sporadic infections have been reported in China. In this study, we obtained high-quality whole viral genomic sequences using a mpox virus-specific amplicon-based sequencing strategy. Our analysis of the phylogenomic characteristics indicated that all eight mpox virus sequences from Guangzhou belonged to the clade IIb lineage B.1.3 cluster. However, we could not locate the exact origins where the virus was imported, based on all the available mpox virus sequences from the Global Initiative on Sharing Avian Influenza Data (GISAID) database (https://gisaid.org/), except for their closest sequence similarity to that was reported from Japan. Novel amino acid mutations were found among the eight cases, suggesting that a local transmission may have occurred in Guangzhou, China.

Data on the viral rebound and safety of nirmatrelvir/ritonavir in lung transplant (LTx) recipients are limited. The study prospectively followed four LTx recipients. Clinical characteristics, viral RNA dynamic in throat swabs, and tacrolimus blood concentration were monitored regularly. All four LTx recipients, aged 35–74 years, were not vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). They got coronavirus disease 2019 (COVID-19) after more than one week of admission during the era of Omicron. All cases received nirmatrelvir/ritonavir (NM/r) within two days of infection, and the relative viral RNA copies dropped quickly. Viral load rebound was observed in all four cases after discontinuation of the first five days of NM/r treatment. Three of them received another 5-days antiviral therapy with NM/r. The duration of positive viral PCR testing was 25-28 days. None of them progressed into severe or critical COVID-19. Tacrolimus was stopped 12 h before NM/r and held during the 5-day course of antiviral therapy. Blood concentration of tacrolimus were maintained at a baseline level during these five days. Tacrolimus was re‐initiated at its baseline daily dose 3-4 days after NM/r therapy. However, during the second round of antiviral therapy with NM/r, the concentration of tacrolimus fluctuated wildly. In conclusion, the 5-day course of NM/r treatment was not sufficient for LTx recipients and the viral rebound was common. More data are needed to clarify whether LTx recipients with SARS-CoV-2 viral rebound could benefit from additional treatment with NM/r.

Although inactivated vaccines against rabies have the advantage of high safety, effective protection against rabies virus (RABV) infection often requires multiple, high-dose immunization. Incorporating a molecular adjuvant into the viral particles has been found to be a useful strategy to promote the immune effectiveness of inactivated vaccines. In this study, we constructed a recombinant virus, rCVS11-LTB, which chimerically expresses a molecular adjuvant heat-labile enterotoxin B subunit (LTB) protein on the surface of the RABV particles. Immunogenicity in vivo was found to be promoted by rCVS11-LTB through the activation of dendritic cells (DCs). Our results demonstrated that inactivated rCVS11-LTB was able to induce higher levels of virus-neutralizing antibodies (VNAs) in both mice and dogs than the parent virus rCVS11, to enhance the cellular immune response and T cell immune memory in mice, and was also able to provide 100% protection in mice from lethal doses of rabies virus, indicating its potential as a safe and effective inactivated rabies vaccine candidate.