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Search Results (233)

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17 pages, 5992 KB  
Article
Development and Evaluation of Quadruplex Droplet Digital PCR Method to Multiplex Detection of Different Respiratory Pathogens of Chickens
by Yingli Mu, Xuejing Wang, Tongchao Dong, Xinran Bao, Qianqian Xu, Tianxiang Lan, Juxiang Liu and Ligong Chen
Animals 2026, 16(1), 139; https://doi.org/10.3390/ani16010139 - 3 Jan 2026
Viewed by 405
Abstract
Chicken respiratory diseases represent multifactorial conditions resulting from viral, bacterial, mycoplasmal pathogens, and environmental factors, causing significant economic losses within the poultry industry. A specific respiratory disease characterized by breathing difficulties and bronchial occlusion due to caseous exudates is termed chicken bronchial obstruction. [...] Read more.
Chicken respiratory diseases represent multifactorial conditions resulting from viral, bacterial, mycoplasmal pathogens, and environmental factors, causing significant economic losses within the poultry industry. A specific respiratory disease characterized by breathing difficulties and bronchial occlusion due to caseous exudates is termed chicken bronchial obstruction. However, the absence of rapid, precise, and highly sensitive diagnostic methods for differentiation of primary respiratory disease pathogens or opportunistic pathogens, including avian influenza virus (AIV), infectious bronchitis virus (IBV), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli), constitutes a substantial challenge. This study developed a quadruplex droplet digital polymerase chain reaction (ddPCR) method that targeted the HA gene of H9 subtype AIV, the M gene of IBV, the Pal gene of P. aeruginosa, and the UidA gene of E. coli. Following the optimization of annealing temperature, sensitivity, and repeatability, the minimum detectable concentrations were determined as 3.02 copies/μL for the HA gene of H9 subtype AIV, 3.08 copies/μL for the M gene of IBV, 3.19 copies/μL for the Pal gene of P. aeruginosa, 3.39 copies/μL for the UidA gene of E. coli. No cross-reactivity was observed with Newcastle disease virus (NDV), H5 subtype AIV, H7 subtype AIV, fowl adenovirus serotype 4 (FAdV-4), infectious laryngotracheitis virus (ILTV), Avibacterium paragallinarum, Streptococcus, Salmonella, Pasteurella multocida, and Staphylococcus aureus. The method demonstrated excellent repeatability, with a coefficient of variation (CV) below 9%. The 185 clinical samples collected in Hebei Province China are tested by both quadruplex ddPCR and quadruplex qPCR method and the results compared. The sensitivity of the quadruplex ddPCR method (57.30%; 106/185) slightly exceeded that of the quadruplex qPCR method (49.73%; 92/185). Pathogens or opportunistic pathogens positive rates obtained via the quadruplex ddPCR were 40.00% for H9 subtype AIV, 33.51% for IBV, 24.32% for P. aeruginosa, and 27.57% for E. coli. In comparison, the positive rates of H9 subtypes AIV, IBV, P. aeruginosa, and E. coli from the quadruplex qPCR were 36.22%, 30.81%, 21.62%, and 24.32%, respectively. The coincidence rates between the two methods were 96.22% for H9 AIV, 97.30% for IBV, 97.30% for P. aeruginosa, and 96.76% for E. coli. These results demonstrated that the quadruplex ddPCR method represented a highly sensitive, specific, and rapid technique for identifying H9 subtype AIV, IBV, P. aeruginosa, and E. coli. Full article
(This article belongs to the Special Issue Advances in Molecular Diagnostics in Veterinary Sciences)
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26 pages, 3426 KB  
Review
The Emerging Threat of Monkeypox: An Updated Overview
by Galal Yahya, Nashwa H. Mohamed, Al-Hassan Soliman Wadan, Esteban M. Castro, Amira Kamel, Ahmed A. Abdelmoaty, Maha E. Alsadik, Luis Martinez-Sobrido and Ahmed Mostafa
Viruses 2026, 18(1), 69; https://doi.org/10.3390/v18010069 - 3 Jan 2026
Viewed by 603
Abstract
Monkeypox (MPOX) is an emerging zoonotic disease caused by monkeypox virus (MPXV), an orthopoxvirus closely related to smallpox. Initially confined to endemic regions in Central and West Africa, MPOX has recently gained global significance with outbreaks reported across multiple continents. MPXV is maintained [...] Read more.
Monkeypox (MPOX) is an emerging zoonotic disease caused by monkeypox virus (MPXV), an orthopoxvirus closely related to smallpox. Initially confined to endemic regions in Central and West Africa, MPOX has recently gained global significance with outbreaks reported across multiple continents. MPXV is maintained in animal reservoirs but is increasingly transmitted from person to person, facilitated by close contact, respiratory droplets, and, in some cases, sexual transmission. Clinically, MPOX presents with fever, lymphadenopathy, and a characteristic vesiculopustular rash, though atypical manifestations have been observed in recent outbreaks, complicating diagnosis. Laboratory confirmation relies on molecular testing, while differential diagnosis must consider varicella, herpes, and other vesicular illnesses. Therapeutic options remain limited; supportive care is the cornerstone of management, but antivirals such as tecovirimat and brincidofovir, as well as smallpox vaccines, have shown efficacy in mitigating disease severity and preventing infection. The unprecedented global outbreak has underscored the importance of surveillance, rapid diagnostics, and coordinated public health responses to contain transmission. This review provides an overview of epidemiology, virology, clinical manifestations, modes of transmission, available diagnostics, and prophylactic and therapeutic strategies against MPOX. We also discuss the role of animal reservoirs, viral evolution, and human-to-human transmission in shaping the dynamics of recent MPOX outbreaks. By summarizing the latest evidence, this review aims to inform clinicians, researchers, and policymakers about key aspects of MPOX biology, clinical management, and prevention, while identifying gaps that warrant future investigation for the control of this and potentially other emerging zoonotic-related pathogens with an impact on human health. Full article
(This article belongs to the Special Issue Emerging and Re-Emerging Viral Zoonoses)
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15 pages, 1408 KB  
Article
Redesigning Isolation Practices: Evaluation of a Comprehensive Protocol for Respiratory Virus Control Including Cycle Threshold (Ct) Value Dynamics
by Stefanie Lemmens, Kevin Janssen, Tine Nelis, Ahmed Elmahy, Noëlla Pierlet, Els Oris and Deborah Steensels
Viruses 2026, 18(1), 40; https://doi.org/10.3390/v18010040 - 25 Dec 2025
Viewed by 424
Abstract
The recent literature has debunked the widespread hypothesis that viruses are primarily transmitted via droplets and not beyond 1.5 m, and transmission via contact has been downplayed. Hence, an evidence-based revision of the existing isolation guidelines for respiratory viruses was needed. Therefore, a [...] Read more.
The recent literature has debunked the widespread hypothesis that viruses are primarily transmitted via droplets and not beyond 1.5 m, and transmission via contact has been downplayed. Hence, an evidence-based revision of the existing isolation guidelines for respiratory viruses was needed. Therefore, a completely new protocol for respiratory virus isolation in terms of personal protective equipment and patient room air purification was evaluated. Isolation relief criteria based on Ct values in follow-up sampling were assessed. A Ct value of <28 was employed as a proxy for potential active replication and associated transmissibility. Between 25% and 50% of patients who tested positive for RSV, HRV, hMPV, or SARS-CoV-2 continued to exhibit high viral loads on day 7 post-initial diagnosis, underscoring the potential for sustained infectivity. Hence, the discontinuation of isolation measures for these patients without follow-up testing may carry a considerable risk of ongoing viral transmission. On the contrary, only 7% of patients positive for Flu and 14% for PIV had a follow-up sample on day 7 with a Ct value of less than 28. Ct values increased more rapidly in influenza, indicating faster viral clearance compared to other respiratory viruses. Based on these results, the policy of a standard 7-day isolation period without follow-up testing could be adopted for influenza-positive patients. Full article
(This article belongs to the Section General Virology)
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27 pages, 1531 KB  
Review
Hospital Influenza Outbreak Management in the Post-COVID Era: A Narrative Review of Evolving Practices and Feasibility Considerations
by Wei-Hsuan Huang, Yi-Fang Ho, Jheng-Yi Yeh, Po-Yu Liu and Po-Hsiu Huang
Healthcare 2026, 14(1), 50; https://doi.org/10.3390/healthcare14010050 - 24 Dec 2025
Viewed by 507
Abstract
Background: Hospital-acquired influenza remains a persistent threat that amplifies morbidity, mortality, length of stay, and operational strain, particularly among older and immunocompromised inpatients. The COVID-19 era reshaped control norms—normalizing N95 use during surges, ventilation improvements, and routine multiplex PCR—creating an opportunity to [...] Read more.
Background: Hospital-acquired influenza remains a persistent threat that amplifies morbidity, mortality, length of stay, and operational strain, particularly among older and immunocompromised inpatients. The COVID-19 era reshaped control norms—normalizing N95 use during surges, ventilation improvements, and routine multiplex PCR—creating an opportunity to strengthen hospital outbreak management. Methods: We conducted a targeted narrative review of WHO/CDC/Infectious Diseases Society of America (IDSA) guidance and peer-reviewed studies (January 2015–August 2025), emphasizing adult inpatient care. This narrative review synthesizes recent evidence and discusses theoretical implications for practice, rather than establishing formal guidelines. Evidence was synthesized into pragmatic practice statements on detection, diagnostics, isolation/cohorting, antivirals, chemoprophylaxis, vaccination, surveillance, and communication. Results: Early recognition and test-based confirmation are pivotal. For inpatients, nucleic-acid amplification tests are preferred; negative antigen tests warrant PCR confirmation, and lower-respiratory specimens improve yield in severe disease. A practical outbreak threshold is ≥2 epidemiologically linked, laboratory-confirmed cases within 72 h on the same ward. Effective control may require immediate isolation or cohorting with dedicated staff, strict droplet/respiratory protection, and daily active surveillance. Early oseltamivir (≤48 h from onset or on admission) reduces mortality and length of stay; short-course post-exposure prophylaxis for exposed patients or staff lowers secondary attack rates. Integrated vaccination efforts for healthcare personnel and high-risk patients reinforce workforce resilience and reduce transmission. Conclusions: A standardized, clinician-led bundle—early molecular testing, do-not-delay antivirals, decisive cohorting and Personal protective equipment (PPE), targeted chemoprophylaxis, vaccination, and disciplined communication— could help curb transmission, protect vulnerable patients and staff, and preserve capacity. Hospitals should codify COVID-era layered controls for seasonal influenza and rehearse unit-level outbreak playbooks to accelerate response and recovery. These recommendations target clinicians and infection-prevention leaders in acute-care hospitals. Full article
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18 pages, 665 KB  
Review
Advances in Human Metapneumovirus Research: Clinical Impact, Diagnostic Innovations, and Therapeutic Challenges
by Md Mostafizur Rahman, Parul Suri, Mimnu Tasnim, Moushumi Afroza Mou, Amatun Noor Prapty and Rakhee Rathnam Kalari Kandy
Pathogens 2025, 14(12), 1277; https://doi.org/10.3390/pathogens14121277 - 12 Dec 2025
Viewed by 893
Abstract
Since its discovery in 2001, Human Metapneumovirus (hMPV) has been identified globally, exhibiting predictable seasonal outbreaks primarily affecting young children, the elderly, and individuals with preexisting health conditions. The virus is transmitted through airborne droplets and is responsible for a notable percentage of [...] Read more.
Since its discovery in 2001, Human Metapneumovirus (hMPV) has been identified globally, exhibiting predictable seasonal outbreaks primarily affecting young children, the elderly, and individuals with preexisting health conditions. The virus is transmitted through airborne droplets and is responsible for a notable percentage of respiratory illnesses, particularly in children under five years of age, with hospitalization rates peaking in the first year of life. The complex immune response elicited by hMPV, characterized by a Th17-like profile and excessive mucus production, contributes to respiratory complications, emphasizing the need for effective management strategies. This review discusses various diagnostic methods, emphasizing the potential of combining serology with RT-PCR to enhance diagnostic accuracy during outbreaks. Furthermore, it addresses the therapeutic approaches, including the promise of recombinant interferons and ongoing research on the use of passive immunity through neutralizing antibodies. A comprehensive overview of hMPV, emphasizing the importance of continued research to improve diagnostic and therapeutic options for this significant respiratory pathogen, offers promising strategies for manipulating responses through targeted interventions. Full article
(This article belongs to the Section Viral Pathogens)
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20 pages, 8620 KB  
Article
Multi-Omics Analysis Reveals Distinct Lipid Remodelling and Mitochondrial Stress in SH-SY5Y Cells Modelling Parkinson’s Disease
by Shu Wang, Zhen Ni, Gaoge Wang, Jingzheng Zhang, Yunfu Tan, Enliang Hong, Yunting Wang, Huan Chen, Hongwei Hou and Qingyuan Hu
Metabolites 2025, 15(12), 781; https://doi.org/10.3390/metabo15120781 - 4 Dec 2025
Viewed by 609
Abstract
Background: Neurotoxin-based in vitro models are commonly used to replicate the mitochondrial dysfunction and oxidative stress associated with Parkinson’s disease (PD). While these models reproduce similar hallmark features of PD pathology, their capacity to capture lipid dysregulation remains less well defined. In [...] Read more.
Background: Neurotoxin-based in vitro models are commonly used to replicate the mitochondrial dysfunction and oxidative stress associated with Parkinson’s disease (PD). While these models reproduce similar hallmark features of PD pathology, their capacity to capture lipid dysregulation remains less well defined. In particular, it is unclear whether different neurotoxins induce distinct glycerophospholipid (GPL) alterations that reflect upstream mechanisms driving mitochondrial impairment. Methods: We conducted a comparative multi-omics analysis in SH-SY5Y cells treated with either 6-hydroxydopamine (6-OHDA) or 1-methyl-4-phenylpyridinium (MPP+). Lipidomic profiling focused on GPL composition, while transcriptomic changes and organelle stress responses were assessed in parallel, including mitochondrial morphology and lipid droplet accumulation. Results: A total of 389 GPL species were identified. MPP+ suppressed the expression of mitochondrial genome-encoded respiratory genes and increased polyunsaturated 20:4 GPL species, while selectively depleting odd-chain lipids. In contrast, 6-OHDA activated pathways related to ferroptosis and endoplasmic reticulum stress, along with an accumulation of 20:3 enriched GPLs. In addition, GPL profiles in MPP+-treated cells showed a stronger similarity to previously reported alterations in PD patient brain tissue. Despite inducing some shared phenotypes such as lipid droplet accumulation and mitochondrial fragmentation, the two models displayed divergent molecular responses. Conclusions: Our findings reveal that MPP+ and 6-OHDA drive fundamentally different patterns of GPL remodelling and cellular stress. These results highlight lipid remodelling as a mechanistic indicator of neurotoxin-induced mitochondrial dysfunction and suggest that the MPP+ model may provide greater relevance for investigating GPL-related processes in PD. Full article
(This article belongs to the Special Issue Metabolomics in Neurodegenerative Diseases, 2nd Edition)
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11 pages, 1328 KB  
Commentary
Mpox Insights: From Structure to Human Cell Interaction
by Md S. Zaman, Robert C. Sizemore, Draven Rodriguez, Emilio Lopez, S. M. Golam Alam, Suleyman Tufa, Juan C. Lopez-Alvarenga, Nuraly S. Akimbekov and Mohammed S. Razzaque
J. Mol. Pathol. 2025, 6(4), 29; https://doi.org/10.3390/jmp6040029 - 21 Nov 2025
Viewed by 646
Abstract
Mpox, a zoonotic viral disease, has emerged as a global concern due to outbreaks in both endemic and non-endemic regions in 2022. Rodents, including African squirrels and Gambian pouched rats, are suspected key reservoirs, with human infections occurring through direct contact with infected [...] Read more.
Mpox, a zoonotic viral disease, has emerged as a global concern due to outbreaks in both endemic and non-endemic regions in 2022. Rodents, including African squirrels and Gambian pouched rats, are suspected key reservoirs, with human infections occurring through direct contact with infected animals or bushmeat consumption. Previously confined to rural Africa, mpox has spread via international travel and the exotic pet trade. Human-to-human transmission occurs mainly via respiratory droplets and direct contact with bodily fluids or lesions. The virus has a double-stranded DNA genome within a lipid envelope. Despite lower mutation rates in DNA viruses, mpox has developed mutations, particularly in genes like F8L, G9R, and F13L, facilitating viral replication and immune evasion. The virus targets immune cells such as monocytes and macrophages, weakening host defenses and prolonging infection. Immunocompromised individuals are at higher risk of severe complications. Although generally self-limiting, severe cases may require antiviral treatment. This article briefly summarizes the therapeutic and preventive strategies, and public health measures to combat zoonotic threats. Full article
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10 pages, 793 KB  
Article
Development and Validation of a Droplet Digital PCR Assay for Detection of Feline Herpesvirus Type-1
by Yaxi Zhou, Danni Wu, Mengle Tang, Zihan Ye, Erkai Feng, Haili Zhang, Guoliang Luo, Zhenjun Wang, Chunxia Wang, Lina Liu and Yuening Cheng
Vet. Sci. 2025, 12(11), 1107; https://doi.org/10.3390/vetsci12111107 - 20 Nov 2025
Viewed by 715
Abstract
Feline herpesvirus type-1 (FHV-1), a double-stranded DNA virus, which is a highly infectious upper respiratory tract infection of felids, particularly in kittens. Droplet digital PCR (ddPCR) provides an absolute quantification method with high sensitivity and accuracy. This study aimed to develop a highly [...] Read more.
Feline herpesvirus type-1 (FHV-1), a double-stranded DNA virus, which is a highly infectious upper respiratory tract infection of felids, particularly in kittens. Droplet digital PCR (ddPCR) provides an absolute quantification method with high sensitivity and accuracy. This study aimed to develop a highly sensitive and accurate ddPCR assay for the detection of FHV-1. We designed primers and a probe targeting the FHV-1 glycoprotein D (gD) gene and evaluated the assay’s limit of detection (LOD), sensitivity, repeatability, and specificity in comparison to quantitative real-time PCR (qPCR). The developed ddPCR assay demonstrated a strong linear dynamic range (R2 ≥ 0.99) and an exceptionally low LOD of 0.18 copies/μL, which was significantly more sensitive than the method qPCR (LOD ~10 copies/μL). Additionally, the assay exhibited high specificity with no cross-reactivity against other common feline pathogens (feline calicivirus, FCV; feline panleukopenia virus, FPV; feline infectious peritonitis virus, FIPV; Bordetella bronchiseptica and Chlamydia felis) and displayed outstanding repeatability (inter-run CV < 1.35). When applied to 118 clinical samples, the ddPCR assay achieved a significantly higher positive detection rate (27.4%) compared to qPCR (14.8%). In conclusion, we have successfully established a reliable ddPCR assay for the absolute quantification of FHV-1, providing a superior tool for laboratory diagnosis and research. Full article
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12 pages, 1792 KB  
Article
Chronic Intermittent Low-Pressure Hypoxia Suppresses Inflammation and Regulates Glycolipids by Modulating Mitochondrial Respiration in db/db Mice
by Xin Jiang, Keqing Yuan, Xiaofeng Ge, Lili Yu, Yufei Cui, Lianhai Jin and Ying Chang
Metabolites 2025, 15(11), 707; https://doi.org/10.3390/metabo15110707 - 30 Oct 2025
Viewed by 695
Abstract
Background/Objectives: Type 2 Diabetes Mellitus (T2DM) is a chronic disease with persistent hyperglycemia as the main clinical manifestation. Chronic Intermittent Hypobaric Hypoxia (CIHH) is a clinical intervention with intermittent low-pressure hypoxic environmental stimulation. The aim of this study was to evaluate the [...] Read more.
Background/Objectives: Type 2 Diabetes Mellitus (T2DM) is a chronic disease with persistent hyperglycemia as the main clinical manifestation. Chronic Intermittent Hypobaric Hypoxia (CIHH) is a clinical intervention with intermittent low-pressure hypoxic environmental stimulation. The aim of this study was to evaluate the therapeutic effect and anti-inflammatory effect of CIHH in db/db mice. Methods: A simulated 5000 m altitude environment was used to intervene db/db mice. db/db mice were divided into an intervention group (6 h/d) (n = 10) and a control group (n = 10); meanwhile, healthy mice were divided into two groups, the intervention group (6 h/d) (n = 10) and the control group (n = 10). The intervention lasted for 6 weeks. Biochemical analyses and pathological tests were performed to evaluate the therapeutic effects, and for the evaluation of mitochondrial respiration, changes in the respiratory capacity of liver mitochondria at various stages of respiration were examined using Oxygraph-2 k. Changes in inflammatory factors in the liver of mice were analyzed using ELISA. Results: Following CIHH intervention, db/db mice exhibited significant reductions in body weight, food intake, FBG, TC, TG, and LDL, along with increased HDL levels. Liver indices, PEPCK, G-6-phosphate dehydrogenase, and GLUT2 decreased, while GLUT4 and p-AMPK increased. Hepatic HE staining revealed reduced lipid droplets in the liver. HOMA-IR decreased while HOMA-IS increased. Hepatocyte mitochondrial respiration-related indicators CI + CII stage RCR, CII stage RCR, and CI stage SCR increased, while CI stage SCR decreased. Inflammation-related factors NLRP3, TNF-α, IL-1β, and IL-6 decreased in liver tissue. Conclusions: CIHH effectively improves gluconeogenesis and insulin resistance in db/db mice, a result potentially linked to enhanced mitochondrial respiratory capacity and anti-inflammatory effects. Therefore, CIHH offers a potential therapeutic approach for type 2 diabetes. Full article
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20 pages, 4358 KB  
Article
Legionella in the City: Unveiling Legionella pneumophila in Hillbrow’s High-Rise Water Systems
by Keletso Emily Buthane, Zaakirah Delair, Tobias George Barnard and Atheesha Singh
Microorganisms 2025, 13(9), 2152; https://doi.org/10.3390/microorganisms13092152 - 15 Sep 2025
Viewed by 1337
Abstract
Urban settings in developing countries present unique challenges such as high population density, inadequate water infrastructure and water supply, all factors that contribute to the growing threat of premise plumbing pathogens such as Legionella. Water droplets from showers and faucets aerosolise Legionella [...] Read more.
Urban settings in developing countries present unique challenges such as high population density, inadequate water infrastructure and water supply, all factors that contribute to the growing threat of premise plumbing pathogens such as Legionella. Water droplets from showers and faucets aerosolise Legionella, which, when inhaled, invade the human respiratory tract to manifest as Legionnaires’ disease. Densely populated, high-rise buildings present an ideal case study for investigating the presence of Legionella. The aim of this study was to investigate the occurrence of Legionella pneumophila (L. pneumophila) in water systems of 15 high-rise buildings in Hillbrow, Johannesburg, South Africa. A total of 67 hot- and cold-water samples and 121 swab samples were collected and analysed for the presence of Legionella pneumophila. Samples were analysed using the Legiolert assay, the South African National Standard (SANS) 11731:2017 method, and the amoeba enrichment method for detecting amoeba-associated Legionella. Molecular confirmation of the pathogen was conducted using conventional PCR and quantitative real-time PCR targeting the mip gene. Legionella pneumophila was found in 93% (14/15) of the buildings that were sampled and was more prevalent in cold-water samples (65%) compared to warm-water (35%) samples. All buildings were positive (100%) for the growth of free-living amoeba (FLA) from water and swab samples. Of these samples, three were confirmed positive for L. pneumophila by PCR and the sequencing alignment results confirmed the identity and relatedness of the isolates to L. pneumophila. Full article
(This article belongs to the Section Public Health Microbiology)
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35 pages, 2122 KB  
Review
Xenobiotic Toxicants and Particulate Matter: Effects, Mechanisms, Impacts on Human Health, and Mitigation Strategies
by Tamara Lang, Anna-Maria Lipp and Christian Wechselberger
J. Xenobiot. 2025, 15(4), 131; https://doi.org/10.3390/jox15040131 - 14 Aug 2025
Cited by 1 | Viewed by 3243
Abstract
Particulate matter (PM), a complex mixture of solid particles and liquid droplets, originates from both natural sources, such as sand, pollen, and marine salts, and anthropogenic activities, including vehicle emissions and industrial processes. While PM itself is not inherently toxic in all its [...] Read more.
Particulate matter (PM), a complex mixture of solid particles and liquid droplets, originates from both natural sources, such as sand, pollen, and marine salts, and anthropogenic activities, including vehicle emissions and industrial processes. While PM itself is not inherently toxic in all its forms, it often acts as a carrier of xenobiotic toxicants, such as heavy metals and organic pollutants, which adhere to its surface. This combination can result in synergistic toxic effects, significantly enhancing the potential harm to biological systems. Due to its small size and composition, PM can penetrate deep into the respiratory tract, acting as a physical “shuttle” that facilitates the distribution and bioavailability of toxic substances to distant organs. The omnipresence of PM in the environment leads to unavoidable and constant exposure, contributing to increased morbidity and mortality rates, particularly among vulnerable populations like the elderly, children, and individuals with pre-existing health conditions. This exposure also imposes a substantial financial burden on healthcare systems, as treating PM-related illnesses requires significant medical resources and leads to higher healthcare costs. Addressing these challenges necessitates effective mitigation strategies, including reducing PM exposure, improving air quality, and exploring novel approaches such as AI-based exposure prediction and nutritional interventions to protect public health and minimize the adverse effects of PM pollution. Full article
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29 pages, 6486 KB  
Article
Optimisation of Atomisation Parameters of Gas–Liquid Two-Phase Flow Nozzles and Application to Downhole Dust Reduction
by Jianguo Wang, Xinni He and Shilong Luo
Processes 2025, 13(8), 2396; https://doi.org/10.3390/pr13082396 - 28 Jul 2025
Viewed by 639
Abstract
Considering the serious hazard of respiratory dust in underground coal mines and the low efficiency of traditional dust-reduction technology, this study optimizes the atomisation parameters of the gas–liquid two-phase flow nozzle through numerical simulation and experimental testing, and designs an on-board dust-reduction system. [...] Read more.
Considering the serious hazard of respiratory dust in underground coal mines and the low efficiency of traditional dust-reduction technology, this study optimizes the atomisation parameters of the gas–liquid two-phase flow nozzle through numerical simulation and experimental testing, and designs an on-board dust-reduction system. Based on the Fluent software (version 2023 R2), a flow field model outside the nozzle was established, and the effects of the air supply pressure, gas-phase inlet velocity, and droplet mass flow rate on the atomisation characteristics were analyzed. The results show that increasing the air supply pressure can effectively reduce the droplet particle size and increase the range and atomisation angle, and that the dust-reduction efficiency is significantly improved with the increase in pressure. The dust-reduction efficiency reached 69.3% at 0.6 MPa, which was the economically optimal operating condition. Based on the parameter optimization, this study designed an annular airborne gas–liquid two-phase flow dust-reduction system, and a field test showed that the dust-reduction efficiency of this system could reach up to 86.0%, which is 53.5% higher than that of traditional high-pressure spraying, and that the dust concentration was reduced to less than 6 mg/m3. This study provides an efficient and reliable technical solution for the management of underground coal mine dust and guidance for promoting the development of the coal industry. Full article
(This article belongs to the Section Chemical Processes and Systems)
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34 pages, 25005 KB  
Article
Indoor Transmission of Respiratory Droplets Under Different Ventilation Systems Using the Eulerian Approach for the Dispersed Phase
by Yi Feng, Dongyue Li, Daniele Marchisio, Marco Vanni and Antonio Buffo
Fluids 2025, 10(7), 185; https://doi.org/10.3390/fluids10070185 - 14 Jul 2025
Viewed by 1023
Abstract
Infectious diseases can spread through virus-laden respiratory droplets exhaled into the air. Ventilation systems are crucial in indoor settings as they can dilute or eliminate these droplets, underscoring the importance of understanding their efficacy in the management of indoor infections. Within the field [...] Read more.
Infectious diseases can spread through virus-laden respiratory droplets exhaled into the air. Ventilation systems are crucial in indoor settings as they can dilute or eliminate these droplets, underscoring the importance of understanding their efficacy in the management of indoor infections. Within the field of fluid dynamics methods, the dispersed droplets may be approached through either a Lagrangian framework or an Eulerian framework. In this study, various Eulerian methodologies are systematically compared against the Eulerian–Lagrangian (E-L) approach across three different scenarios: the pseudo-single-phase model (PSPM) for assessing the transport of gaseous pollutants in an office with displacement ventilation (DV), stratum ventilation (SV), and mixing ventilation (MV); the two-fluid model (TFM) for evaluating the transport of non-evaporating particles within an office with DV and MV; and the two-fluid model-population balance equation (TFM-PBE) approach for analyzing the transport of evaporating droplets in a ward with MV. The Eulerian and Lagrangian approaches present similar agreement with the experimental data, indicating that the two approaches are comparable in accuracy. The computational cost of the E-L approach is closely related to the number of tracked droplets; therefore, the Eulerian approach is recommended when the number of droplets required by the simulation is large. Finally, the performances of DV, SV, and MV are presented and discussed. DV creates a stratified environment due to buoyant flows, which transport respiratory droplets upward. MV provides a well-mixed environment, resulting in a uniform dispersion of droplets. SV supplies fresh air directly to the breathing zone, thereby effectively reducing infection risk. Consequently, DV and SV are preferred to reduce indoor infection. Full article
(This article belongs to the Special Issue Respiratory Flows)
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32 pages, 1959 KB  
Review
hMPV Outbreaks: Worldwide Implications of a Re-Emerging Respiratory Pathogen
by Alexandra Lianou, Andreas G. Tsantes, Petros Ioannou, Efstathia-Danai Bikouli, Anastasia Batsiou, Aggeliki Kokkinou, Kostantina A. Tsante, Dionysios Tsilidis, Maria Lampridou, Nicoletta Iacovidou and Rozeta Sokou
Microorganisms 2025, 13(7), 1508; https://doi.org/10.3390/microorganisms13071508 - 27 Jun 2025
Cited by 5 | Viewed by 5525
Abstract
Human metapneumovirus (hMPV), a member of the Pneumoviridae subfamily, has emerged as a significant etiological agent of acute respiratory tract infections across diverse age groups, particularly affecting infants, the elderly, and immunocompromised individuals. Since its initial identification in 2001, hMPV has been recognized [...] Read more.
Human metapneumovirus (hMPV), a member of the Pneumoviridae subfamily, has emerged as a significant etiological agent of acute respiratory tract infections across diverse age groups, particularly affecting infants, the elderly, and immunocompromised individuals. Since its initial identification in 2001, hMPV has been recognized globally for its seasonal circulation pattern, predominantly in late winter and spring. hMPV is a leading etiological agent, accounting for approximately 5% to 10% of hospitalizations among pediatric patients with acute respiratory tract infections. hMPV infection can result in severe bronchiolitis and pneumonia, particularly in young children, with clinical manifestations often indistinguishable from those caused by human RSV. Primary hMPV infection typically occurs during early childhood; however, re-infections are frequent and may occur throughout an individual’s lifetime. hMPV is an enveloped, negative-sense RNA virus transmitted through respiratory droplets and aerosols, with a 3–5-day incubation period. The host immune response is marked by elevated pro-inflammatory cytokines, which contribute to disease severity. Advances in molecular diagnostics, particularly reverse transcription–quantitative polymerase chain reaction (RT-qPCR) and metagenomic next-generation sequencing (mNGS), have improved detection accuracy and efficiency. Despite these advancements, treatment remains largely supportive, as no specific antiviral therapy has yet been approved. Promising developments in vaccine research, including mRNA-based candidates, are currently undergoing clinical evaluation. This review synthesizes current knowledge on hMPV, highlighting its virological, epidemiological, and clinical characteristics, along with diagnostic advancements and emerging therapeutic strategies, while underscoring the critical role of continued research and sustained preventive measures—including vaccines, monoclonal antibodies, and non-pharmaceutical interventions—in mitigating the global burden of hMPV-related disease. Full article
(This article belongs to the Special Issue Emerging and Re-Emerging Infections in the Immunocompromised Host)
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21 pages, 2246 KB  
Review
Potential Resistance Mechanisms Exhibited by Cystic Fibrosis Patients Against SARS-CoV-2
by Yasmin K. Elsharabassi, Nuha T. Swaidan and Mohamed M. Emara
Viruses 2025, 17(7), 919; https://doi.org/10.3390/v17070919 - 27 Jun 2025
Viewed by 1052
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the 2019 coronavirus disease pandemic. The virus primarily spreads through person-to-person contact via aerosols and droplets, contributing to high case numbers and related morbidities. SARS-CoV-2 targets the respiratory tract, causing acute [...] Read more.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the 2019 coronavirus disease pandemic. The virus primarily spreads through person-to-person contact via aerosols and droplets, contributing to high case numbers and related morbidities. SARS-CoV-2 targets the respiratory tract, causing acute respiratory distress syndrome, particularly in immunocompromised individuals such as those with cystic fibrosis (CF). CF is a life-threatening genetic disorder caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, leading to impaired respiratory function and recurrent severe respiratory symptoms. Despite their potential vulnerability, CF patients have shown a lower incidence of severe COVID-19, suggesting protective factors against SARS-CoV-2. Differential expression of the ACE2 receptor, crucial for viral entry, and other host factors, such as TMPRSS2, may play a role in this resistance to SARS-CoV-2. Analyzing the genomics and transcriptomics profiles of CF patients could provide insights into potential resistance mechanisms. The potential resistance mechanisms include blood and extracellular ATP levels, a deleted/dysfunctional CFTR gene, ACE and ACE2 regulation and expression, ACE and ACE2 polymorphism effects, host proteins and SARS-CoV-2 interactions, and SMN1 and ACE/ACE2 interactions. This review discusses the underlying factors and potential resistance mechanisms contributing to CF patients’ responses to SARS-CoV-2 infection. The review provides an opportunity to further investigate future therapy and research through understanding the underlying potential resistance mechanisms exhibited by CF patients against SARS-CoV-2, including ACE and ACE2 polymorphisms. Full article
(This article belongs to the Section Coronaviruses)
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