Biosafety and Health最新文献

Monkeypox (mpox) outbreak in 2022 has caused more than 91,000 cases, has spread to 115 countries, regions, and territories, and has thus attracted much attention. The stability of poxvirus particles in the environment is recognized as an important factor in determining their transmission. However, few studies have investigated the persistence of poxviruses on material surfaces under various environmental conditions, and their sensitivity to biocides. Here, we systematically measured the stability of vaccinia virus (VACV) under different environmental conditions and sensitivity to inactivation methods via plaque assay, quantitative real-time polymerase chain reaction (qPCR), and Gaussia luciferase (G-luciferase) reporter system. The results show that VACV is stable on the surface of stainless steel, glass, clothing, plastic, towel, A4 paper, and tissue and persists much longer at 4 °C and −20 °C, but is effectively inactivated by ultraviolet (UV) irradiation, heat treatment, and chemical reagents. Our study raises the awareness of long persistence of poxviruses in the environment and provides a simple solution to inactivate poxviruses using common disinfectants, which is expected to help the control and prevention of mpox virus and future poxvirus outbreaks.

Coxsackievirus A6 of the D3a genotype (CVA6 D3a) is a primary pathogen causingmainland of China's hand, foot, and mouth disease (HFMD). Viral-like particle (VLP) vaccines represent a potential candidate vaccine to prevent HFMD. This study collected Anti-CVA6 D3a VLPs serum from BALB/c female mice immunized using CVA6 D3a VLPs. The neutralizing antibody levels were compared against the representative 14-JX2018 (D3a) and N4-YN2015 (D3b) strains between the antisera of different immune pathways. The immunoprotective effect of anti-CVA6 D3a VLPs against these strains was monitored using pathological sections and immunohistochemical results of lung and skeletal muscle tissues in seven-day-old Institute of Cancer Research (ICR) mice. Immunological protection against different branches of viruses was evaluated in 7-day-old (serum passive immune protection) and 14-day-old (VLPs active immune protection) neonatal ICR mice models. Serum-neutralizing antibody levels were positively correlated with the number of immunizations and higher against 14-JX2018 than against N4-YN2015. Furthermore, these levels were significantly higher with abdominal injection than intramuscular injection. The immunized serum of 7-day-old ICR mice inoculated three times was 100 % protected against CVA6 D3a 14-JX2018 (lethal titer: 10^6.25 TCID₅₀) and CVA6 D3b N4-YN2015 (lethal titer: 10^5.25TCID₅₀) fatal attacks, respectively. For ICR mice that have completed two active immunizations for 14 days, both CVA6 D3a 14-JX2015 (challenge titer: 10^8.25 TCID₅₀) and CVA6 D3b N4-YN2015 (challenge titer: 10^7.25 TCID₅₀) were used for the challenge, and the mice were able to survive. Overall, the CVA6 D3a VLPs prepared in this study are a potential vaccine candidate for CVA6, as it has the optimal protective effect against both CVA6 D3a and D3b evolutionary branches viruses.

The coronavirus disease of 2019 (COVID-19), a global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can result in severe health complications. In addition to physical preventative measures, pharmaceutical intervention is also crucial. Numerous natural products from medicinal fungi have shown promise as potential antiviral drugs and may serve as a source of effective components with antiviral activity against SARS-CoV-2 and other coronaviruses. In this study, we developed a workflow that integrates viral infection inhibition assays at both cellular and molecular levels, as well as molecular separation and characterization, to screen and identify natural products with antiviral activity. Using this workflow, we screened 167 extracts extracted from 36 medicinal fungi using optimized extraction methods. We assessed the antiviral effects of these extracts by measuring their ability to inhibit SARS-CoV-2 infection and receptor binding domain - human angiotensin-converting enzyme 2 (RBD-hACE2) binding in vitro. Following charge- and size-based characterization of the active compounds through filtration and chromatographic fractionation, mass spectrometry characterization of the fractionated compounds revealed that the active components are polysaccharides and determined their monosaccharide residue composition. Our findings provide new insights into the antiviral potential of natural products and their screening strategies and may contribute to the development of effective antiviral therapeutics against COVID-19 and other diseases.

Worldwide, infections caused by drug-resistant pathogens constitute a significant challenge threatening therapeutic efforts. According to the World Health Organization (WHO), antimicrobial resistance (AMR) ranks among the top 10 global public health threats. Organisms with a high rate of multiple host adaptivity, significant genetic diversity (multiple lineages), high virulence factors, and genetic exchange have been isolated from various sources (humans, animals, and the environment) even without exposure to prior antibiotics. Till now, the source of AMR and how resistant clones are selected in the environment remain largely elusive, and potential anthropogenic transmission has been reported in different studies. Various drug-resistant pathogens, lineages, resistant clones, outbreak clusters, plasmid replicates, and genes that play a critical role in resistance dissemination have been identified. Maintenance of certain multidrug-resistant (MDR) determinants has also been shown to enhance or support the propagation of MDR. So far, significant advances have been made in understanding the burden of AMR. However, overcoming AMR requires a holistic approach, as there is no single approach with sufficient precision to curb the threat. While strengthening AMR surveillance efforts is essential, as we have shown, there is also a need to intensify efforts to strengthen therapeutic interventions, especially in priority regions such as Africa. Herein, we discussed the burden of AMR and the dissemination of AMR in humans, animals, and the environment (non-medical drivers). We further delved into the big questions on Africa and discussed how therapeutic interventions involving vaccines and other viable biomaterials could be pivotal in reducing the burden of AMR to the barest minimum.

The real-time reverse transcription-polymerase chain reaction (RT-PCR) test is the gold standard for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection. Proper specimen collection and obtaining a sufficient specimen are the most essential steps for laboratory diagnosis. The nasopharyngeal (NP) swab is recommended as the reference collection method. However, NP swab collection is invasive and uncomfortable for patients and poses some risk to healthcare workers. This study aimed to compare the efficacy of SARS-CoV-2 RNA detection from surgical masks with the NP swab method using RT-PCR testing. Of 269 patients, RT-PCR RNA from NP swabs was detected among 82 patients (30.5%) and was undetected among 187 patients (69.5%). All patients were tested for SARS-CoV-2 RNA from surgical masks. SARS-CoV-2 RNA was detected in 25/82 (30.5%) surgical mask filters, while undetected among 57 (69.5%). For the surgical mask with an average use time of 7.05 h, the sensitivity was 30.5%, the specificity was 100.0%, with positive predictive value of 100.0% and negative predictive value of 76.2%. Therefore, surgical masks could be an alternative non-invasive specimen source for SARS-CoV-2 RT-PCR testing. The results of our study suggest that the test could be employed after wearing surgical masks for at least 8-12 h, with increased sensitivity when used for more than 12 h.

The risk factors of severe infections in children during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in Beijing remain elusive. SARS-CoV-2-positive children admitted to the intensive care unit (ICU) with collected plasma specimens were enrolled and screened for common pathogens using capillary electrophoresis-based multiplex PCR from December 12, 2022, to January 24, 2023. The SARS-CoV-2 sub-variants were identified using next-generation sequencing. Plasma was positive for two (positive; P), one (suspicious; S), or no (negative; N) SARS-CoV-2 genes were classified as plasmatic RNA-positive (RNAemia; P + S) or without RNAemia (N). Clinical and laboratory data of the enrolled cases were then collected and analyzed. The 34 enrolled children included 26 males and 24 younger than three years. All were negative for other respiratory pathogens. BF.7.14 (18/29) was the predominant subvariant. Viral loads in respiratory specimens, hours from symptom onset to the first respiratory specimen collection (time-variable), with comorbidities and BF.7.14 and BA.5.2 distributions were significantly different in P vs. N and RNAemia vs. without RNAemia group. Among most cases, the T lymphocyte ratios decreased, while the cytokine level and the B lymphocyte ratio increased. The time variables were 2.22 ± 2.05 and 4.00 ± 2.49 days in BF.7.14 and BA.5.2 infections, respectively. In conclusion, SARS-CoV-2 was more likely to cause severe infections among males aged ≤ 3 years old with comorbidities during the SARS-CoV-2 outbreak in Beijing, while RNAemia is more common in children at the early stage of severe BF.7.14 infections, and most had high cytokine levels and B-cell activation.

Antimicrobial resistance (AMR) is a growing global threat, especially in low- and middle-income countries (LMICs), causing prolonged illnesses, heightened antimicrobial use, increased healthcare expenses, and avoidable deaths. If not tackled, AMR could force 24 million people into severe poverty by 2030 and hinder progress on Sustainable Development Goals (SDGs). AMR spreads through interconnected ecosystems, with humans, animals, and the environment serving as reservoirs. Pharmaceutical wastewater, loaded with antibiotics and resistance genes, poses a significant environmental risk, mainly due to inadequate treatment and irresponsible disposal. The pharmaceutical industry is a notable contributor to environmental antibiotic pollution, with varying effluent management practices. Contaminated pharmaceutical wastewater discharge harms water sources and ecosystems. Urgent collaborative efforts are needed across policymakers, regulators, manufacturers, researchers, civil society, and communities, adopting a One Health approach to curb AMR's spread. Developing global standards for pharmaceutical effluent antibiotic residues, effective treatment methods, and improved diagnostics are vital in addressing AMR's environmental impact while safeguarding public health and the environment. National action plans should encompass comprehensive strategies to combat AMR. Preserving antibiotic efficacy and ensuring sustainable production require a united front from all stakeholders.