Search Results (6,378)

Legionella species are ubiquitous bacteria found worldwide in water, moist environments, soils, and compost. Infection occurs through the inhalation of aerosols, leading to either Pontiac fever or Legionnaires’ disease (LD). Current routine diagnostics typically combine culture-based isolation with Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for species identification and the Latex Agglutination Test (LAT) for serotyping. However, this workflow is fragmented: MALDI-TOF MS lacks serogroup-specific resolution, while LAT relies on subjective visual interpretation. Therefore, this study evaluated Fourier-transform infrared spectroscopy (FT-IR) as a rapid, high-resolution typing method for Legionella isolates to assess its potential as a single-step diagnostic tool. A total of 200 clinical and environmental Legionella isolates were analyzed using FT-IR, including L. pneumophila serogroups (SG) 1–15 and various non-pneumophila species. Spectral data were analyzed using Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA). While MALDI-TOF MS provided accurate species identification, FT-IR spectroscopy demonstrated superior typing capabilities by successfully distinguishing L. pneumophila SG 1 distinct from the SG 2–15 complex and allowing for clear discrimination of most non-pneumophila species. Additionally, FT-IR resolved isolates that showed ambiguous or non-reactive results in LAT. These findings demonstrate that FT-IR overcomes the serotyping limitations of MALDI-TOF MS and offers a more objective, cost-efficient extension to the current multi-step routine, potentially closing the diagnostic gap between simple species identification and deep strain characterization. Full article

Human African Trypanosomiasis (HAT) and Malaria are serious infectious diseases endemic in tropical regions, caused by protozoan parasites, and necessitating an urgent development of new antiprotozoal drugs. As part of our ongoing search for new antiprotozoal steroidal alkaloids from plants, we investigated the methanolic stem bark extract of Holarrhena pubescens (Apocynaceae). H. pubescens is a tropical tree that some Kenyan coastal communities have long used to treat various ailments, including fever and stomach pain. The crude extract, alkaloid fraction, and 16 subfractions acquired through centrifugal partition chromatography (CPC) displayed promising in vitro antiprotozoal activity against Trypanosoma brucei rhodesiense (Tbr) and Plasmodium falciparum (Pf). Partial least squares (PLS) regression modeling of UHPLC/+ESI QqTOF-MS data and the antiprotozoal activity data of the crude extract and its fractions was performed to predict compounds that may be responsible for the observed antiplasmodial activity. Chromatographic separation of the alkaloid fraction afforded one new steroidal alkaloid (5), along with 18 known compounds (1, 2, 4, 6–20), and one artifact (3) that was presumably formed during the acid–base extraction process. The structural characterization of the isolated compounds was accomplished using UHPLC/+ESI-QqTOF-MS/MS and NMR spectroscopy. The isolated compounds were tested for their in vitro antiprotozoal properties against the two aforementioned pathogens, as well as for their cytotoxicity against mammalian cells (L6 cell line). Compounds 2 and 16 (IC₅₀ = 0.2 μmol/L) demonstrated the highest antitrypanosomal activity, with compound 2 showing the highest selectivity (SI = 127). The new compound 5 exhibited the strongest antiplasmodial activity and selectivity against Pf (IC₅₀ = 0.7 μmol/L, SI = 43). Our findings provide further promising antiprotozoal leads for HAT and Malaria. Full article

Pestiviruses, such as bovine viral diarrhea virus (BVDV) or classical swine fever virus (CSFV), are members of the family Flaviviridae and infect a broad range of species, causing significant economic losses in livestock. A unique feature of pestiviruses is the E^rns protein, which is part of the glycoprotein complex at the surface of the virion, but it is also secreted as an RNase that functions as an interferon (IFN) antagonist. This dual nature makes E^rns a particularly complex and multifunctional protein, highlighting its importance for understanding pestivirus biology. Bungowannah pestivirus (BuPV) was reported to exhibit high genetic plasticity, making it suitable for engineering recombinant tools. In this study, we generated a recombinant BuPV expressing green fluorescent protein (GFP) fused to the N-terminus of the E^rns protein from BVDV. The GFP-E^rns fusion was detected by fluorescence microscopy and remained stable across five serial passages. The recombinant virus infected all tested mammalian cell lines but replicated more slowly than the parental BuPV stock. RNase activity assays confirmed retention of enzymatic function. These results demonstrate stable expression, broad infectivity, and preserved activity of GFP-E^rns in the recombinant BuPV, indicating that this might be a useful tool for further investigations on pestivirus pathogenesis. Full article

Murine typhus (also called flea-borne or endemic typhus) is an undifferentiated febrile illness caused by the bacterium Rickettsia typhi. The disease, transmitted by rat and cat fleas, is endemic to seaboard regions worldwide. Recently, murine typhus has reemerged as an increasingly recognized cause of febrile illness in the United States, especially in Texas and Southern California. In addition to fever, manifestations often include headache, malaise, myalgias, and a maculopapular rash in approximately half of cases. Although usually considered a mild illness, when untreated, symptoms can last up to 3 weeks. Severe manifestations such as pneumonitis, acute kidney injury, and meningoencephalitis may occur. Historically, death has occurred in 0.4%, but in Southern California, the case fatality rate has been recently recorded at 1.8%. As murine typhus has reemerged, there have been growing reports that this infection has triggered hemophagocytic lymphohistiocytosis, a life-threatening hyperinflammatory syndrome. We herein report two fatal cases of hemophagocytic lymphohistiocytosis secondary to murine typhus. Autopsy revealed typhus group rickettsial antigen in tissues via immunohistochemistry, along with hemophagocytosis. Interestingly, the classic vascular and perivascular histopathologic findings associated with disseminated rickettsial infection were absent. These findings highlight an aberrant inflammatory cascade leading to hemophagocytic lymphohistiocytosis. Full article

Flaviviruses are arthropod-borne RNA viruses associated with significant human diseases globally. There are no effective direct-acting antivirals approved to treat these viral infections. Given its critical role in viral replication, the RNA-dependent RNA polymerase (RdRp) is a logical target for antiviral drug development. Remdesivir (formerly GS-5734), a 1′-cyano modified C-adenosine monophosphate prodrug, was the first US Food and Drug Administration (FDA) approved antiviral for coronavirus disease 2019 (COVID-19) and was also shown to inhibit flavivirus replication. GS-7682, a 4′-cyano modified C-adenosine prodrug, exhibits a broad-spectrum antiviral activity. Here, we determined the anti-flavivirus potency of both remdesivir and GS-7682 and characterized their active triphosphate forms, GS-443902 and GS-646939, respectively, against a panel of purified flavivirus RdRps. These include dengue, Japanese encephalitis, West Nile, yellow fever, and Zika. Enzyme kinetics demonstrate efficient RNA incorporation of GS-443902 and GS-646939. GS-646939 acts as an immediate chain terminator. Conversely, GS-443902 acts through a template-dependent inhibition mechanism by impeding the incorporation of the complementary UTP. Both mechanisms correlate with anti-flavivirus activity, although remdesivir is generally superior. The data demonstrate that immediate chain termination is not necessarily a preferred mechanism of action of nucleotide analogs. Template-dependent inhibition should also be considered, especially for viruses lacking intrinsic proofreading activities. Full article

A rare but potentially fatal hyperinflammatory disease that develops following SARS-CoV-2 infection is called multisystem inflammatory syndrome in children (MIS-C). Mucocutaneous manifestations are common and frequently overlap with other pediatric inflammatory illnesses, including Kawasaki disease, and may serve as early diagnostic indicators. We describe a 6-year-old girl who was previously healthy but was hospitalized in the pediatric intensive care unit due to a high-grade fever, toxic appearance, and quickly progressing mucocutaneous symptoms, such as bilateral non-purulent conjunctivitis and broad maculopapular rash. Myocardial dysfunction, severe anemia and thrombocytopenia, respiratory failure necessitating mechanical ventilation, and hypotensive shock complicated the clinical course. Laboratory tests showed positive SARS-CoV-2 serology and significantly increased inflammatory markers. Several microbiological tests came up negative. Bacterial sepsis and Kawasaki diseases were not included. A diagnosis of MIS-C was made based on clinical, laboratory, and epidemiological data. In addition to supportive intensive care, the patient received systemic corticosteroids and intravenous immunoglobulin. After two weeks, she was released in a stable condition after gradually improving clinically and biochemically. This instance emphasizes how crucial it is to identify noticeable mucocutaneous manifestations as early warning signs of MIS-C. Immunomodulatory therapy must be started as soon as possible in order to minimize serious consequences and enhance the prognosis of afflicted infants. Full article

Rift Valley fever (RVF) transmission has intensified in southwestern Uganda since 2016. To quantify human and livestock exposure and associated risks, we conducted a cross-sectional serosurvey in Isingiro, Kabale and Rubanda districts between October and November 2023. A total of 766 humans and 2383 livestock were sampled and tested for RVF antibodies using ELISA, with structured questionnaires capturing demographic, behavioral and environmental data. Human seroprevalence was 11.5% (88/766), varying by district (13.8% Isingiro, 11.8% Rubanda, 6.8% Kabale; p = 0.04). Independent predictors from the multivariate model included raw-meat consumption (aOR 6.11; 95% CI 1.16–27.80), cattle ownership (aOR 2.33; 95% CI 1.27–4.36), male sex (aOR 1.64; 95% CI 1.02–2.66) and younger age compared with ≥50 years (31–49 years: aOR 2.02; 95% CI 1.20–3.48; 18–30 years: aOR 2.37; 95% CI 1.04–5.14). Herd-level seroprevalence was 42.5% (204/480), associated with cattle presence (aOR 6.48; 95% CI 4.10–10.40), lack of carcass burial (aOR 15.70; 95% CI 4.23–63.60), on-farm slaughter (aOR 2.14; 95% CI 1.21–3.89) and increased mosquito activity (aOR 1.75; 95% CI 1.13–2.73). Animal-level seroprevalence was 14.6% (347/2383), highest in cattle (33.8%), with cattle having markedly higher odds than goats (aOR 6.73; 95% CI 4.96–9.14). These findings demonstrate substantial transmission and highlight cattle-centered interfaces as primary targets for control to humans. Full article

Background/Objectives: African swine fever virus (ASFV), the causative agent of African swine fever (ASF), is a highly contagious virus affecting both domestic and feral pig populations with mortality rates approaching 100% within one week of infection. Currently, there are limited treatments or vaccines available to control the disease. Although ASF is endemic in sub-Saharan Africa, the virus has also spread widely, reaching regions of the European Union, Russia, China, Southeast Asia, and, more recently, to the Dominican Republic and Haiti, bringing the threat closer to the United States (U.S.). ASF introduction to the U.S. would have severe consequences for swine producers and the national pork industry. Consequently, there is an urgent need to develop effective vaccine strategies to manage ongoing outbreaks abroad and mitigate the risk of future ASF incursions. Recent efforts have identified several ASFV epitopes and evaluated them in experimental vaccine trials. However, these vaccine candidates have elicited limited protective immune responses and have not demonstrated full protective efficacy. Methods: In this study, we employed in silico modeling and epitope prediction tools to design a synthetic multiepitope ASF protein incorporating key immunogenic regions of ASFV. The goal was to generate a single-antigen construct capable of inducing broad and robust immune responses when formulated with an established nanoparticle-based vaccine platform. The multiepitope ASF protein was subsequently expressed and entrapped into mannose-conjugated chitosan (M-CS) nanoparticles for vaccine formulation. The candidate vaccine, formulated with M-CS nanoparticle-entrapped adjuvant (ADU S100), was administered intramuscularly to pigs, and both T- and B-cell responses were assessed following the primary (DPV 22) and booster (DPV 42) doses. Results: Our M-CS ASF protein vaccine elicited antigen-specific T- and B-cell responses, both of which are recognized as central correlates of protection against ASFV. Conclusions: These promising preliminary immunological findings suggest that this nanoparticle vaccine has the potential to confer protection against ASFV challenge, a hypothesis that will be examined in future studies. Full article

Increased international trade and tourist flows are key factors in the introduction of transboundary animal diseases such as African swine fever (ASF). Despite the availability of sufficiently detailed data on legal commercial trade, the movement of pork products intended for personal consumption is insufficiently reported and difficult to track when carried in passenger luggage, and may act as an introduction pathway. In this study, we analyze the risk of ASF reintroduction in Sardinia, an island that has recently achieved disease-free status after a long epidemic. An anonymous questionnaire on travelers’ awareness of ASF and their food transportation habits was administered at the main Sardinian airports between July and December 2025, and a total of 6525 responses were received. The results show a low level of knowledge regarding ASF, with approximately 95% of respondents stating they were unaware of the disease, while almost 10% of travelers reported having transported meat or other pork products, often originating from countries where the virus is circulating. Our investigation highlights how passenger flows, especially during the seasonal peak, could act as a vector for potential disease reintroduction through the transport of pork products. The results stress that the adoption of behavioral survey tools is essential to supplement traditional surveillance systems, highlighting the need to improve targeted communication strategies at both ports and airports in order to reduce the risk of virus reintroduction and protect regional livestock. Full article

The detection rate of Porcine Reproductive and Respiratory Syndrome Virus type 1 (PRRSV-1) in China has been increasing, with its growing genetic diversity and evolving pathogenicity posing significant challenges to disease control. In this study, a novel PRRSV-1 strain, designated GD18-2, was identified from a pig farm in Guangdong Province that experienced an outbreak despite vaccination with a PRRSV-2 vaccine. Whole-genome sequencing indicated that the GD18-2 strain possesses a genome length of 14,932 bp and exhibits 81.4% to 83.9% nucleotide identity with classical PRRSV-1 strains. Phylogenetic analyses based on both the complete genome and the ORF5 gene indicated that GD18-2 belongs to a distinct, new lineage. A unique amino acid deletion (positions 306–357) was identified in the non-structural protein Nsp2, along with specific mutations within the hypervariable regions of the structural proteins GP3 and GP4. Pathogenicity assessment demonstrated that GD18-2 induced fever, respiratory symptoms, and mortality in piglets. In pregnant sows, it caused reproductive failure (abortion, stillbirth, weak piglets) and was capable of vertical transmission via the placenta. This study highlights the emergence of a PRRSV-1 strain with a unique genetic background and high pathogenicity in southern China, underscoring the necessity for enhanced molecular epidemiological surveillance and updated control strategies. Recombination analysis using RDP4 revealed no significant recombination events in GD18-2. Full article

The global spread of lumpy skin disease (LSD), a devastating cattle disease caused by the lumpy skin disease virus (LSDV), is hampered by the lack of a practical small animal model for vaccine evaluation. Here, we established a mouse model by challenging C57BL/6 mice with goatpox virus (GTPV), a close relative of LSDV. Intranasal inoculation with a high dose (10^4.5 TCID₅₀) of GTPV induced robust infection characterized by weight loss, fever, high viral loads in the lungs and livers, and significant pulmonary pathology including immune cell infiltration and alveolar wall thickening. Infected mice mounted potent humoral immunity, with rapid IgM and sustained IgG and GTPV-specific binding antibody responses. The infection also elicited a dynamic cellular immune response, marked by biphasic IFN-γ production and dose-dependent increases in IL-17A and TNF-α. This GTPV-based murine model effectively recapitulates critical aspects of LSDV pathogenesis and immunity, providing a valuable and accessible tool for the accelerated development and preclinical assessment of novel LSDV vaccines. Full article

Background: Transrectal ultrasound-guided prostate biopsy remains the gold standard in diagnosing prostate cancer, but is associated with infectious and non-infectious complications. Increasing fluoroquinolone resistance and regulatory restrictions have prompted evaluation of alternative prophylactic strategies, including fluoroquinolone-sparing agents and targeted prophylaxis. This study compared ciprofloxacin and fosfomycin as empirical prophylactic agents, focusing on microbiological concordance, clinical outcomes, and patient-reported outcomes. Methods: In this prospective observational study, 265 men undergoing transrectal ultrasound-guided prostate biopsy received empirical antibiotic prophylaxis with either ciprofloxacin (n = 146) or fosfomycin trometamol (n = 119). Rectal swabs were obtained prior to biopsy, and antimicrobial susceptibility was analyzed post hoc. Infectious and non-infectious complications were recorded. Lower urinary tract symptoms (IPSS), erectile function (IIEF-5), and patient-reported quality of life were assessed before and after biopsy. Results: Microbiological concordance between administered prophylaxis and rectal flora susceptibility was higher in the ciprofloxacin group than in the fosfomycin group (80.1% vs. 65.0%, p = 0.007), while resistance rates were similar (10.9% vs. 10.2%). Post-biopsy fever occurred in 5.3% of patients, and hospitalization was required in 3.1%, with no significant differences between prophylaxis groups. IPSS increased significantly after biopsy (p < 0.001), while IIEF-5 scores remained unchanged. Patients with microbiological concordance reported significantly better post-biopsy quality of life (p = 0.006). Conclusions: Ciprofloxacin and fosfomycin showed similar safety profiles as empirical prophylaxis before transrectal prostate biopsy. Although ciprofloxacin achieved higher microbiological concordance, fosfomycin remains a viable alternative. The link between microbial concordance and improved patient-reported quality of life underscores the importance of targeted prophylaxis and supports antimicrobial stewardship in prostate cancer diagnostics. Full article

Trollius chinensis Bunge (TCB), a perennial Ranunculaceae herb, produces Flos Trollii-dried flowers with medicinal properties including heat clearing, detoxification, and relieving oral/throat discomfort, eye pain, and cold-induced fever. TCB is mainly cultivated in northern China, while Trollius ledebouri Rchb. (TLR), distributed in Heilongjiang’s Great Xing’an Mountains, is morphologically similar to TCB. However, their regulatory statuses are inconsistent, and comprehensive comparative studies are lacking. This study adopted morphological assessment, microscopy, DNA barcoding, and physicochemical analysis to explore whether TLR could be a potential alternative source of Flos Trollii. Key differences were identified: TLR’s sepals are shorter than petals, whereas TCB’s sepals and petals are nearly equal in length; TLR has brown secretory structures absent in TCB. Genetic distance analysis showed high conservation in ITS2 and trnL-trnF sequences between the two species, but psbA-trnH sequence divergence exceeded the 0.05 threshold. HPLC quantification revealed that TLR contained slightly higher levels of orientin and vitexin than TCB. HPLC quantification revealed that TLR contained slightly higher levels of orientin (5.370–5.377 mg/g) and vitexin (1.954–2.053 mg/g) compared to TCB (orientin: 4.493–4.620 mg/g; vitexin: 1.361–1.451 mg/g). Collectively, TLR exhibits comparable flavonoid content and holds potential as an alternative Flos Trollii source. Given the limited bioactive compounds analyzed, future research should conduct comprehensive metabolomic profiling to fully evaluate its phytochemical composition and medicinal value. These data establish chemotaxonomic markers for Trollius authentication in herbal medicine. Full article

As survival rates for children with cancer and immune disorders have improved, clinical focus has shifted toward managing serious treatment-related complications. Intestinal perforation remains life-threatening and is typically diagnosed by signs of peritonitis and inflammation. This report presents three high-risk pediatric patients who developed severe intestinal perforation without the usual clinical symptoms. Each patient was receiving high-dose corticosteroids and/or targeted biologic immunomodulators (ruxolitinib, anakinra, tocilizumab, eculizumab). Classic indicators such as fever, leukocytosis, hemodynamic instability, and abdominal pain were absent, despite surgical findings of fecal contamination and bowel necrosis. All three patients survived to hospital discharge. These cases demonstrate that potent immunomodulatory therapies can mask the physiological response to perforation. Relying solely on traditional clinical signs may delay diagnosis. In this population, subtle findings such as persistent gastrointestinal bleeding, feeding intolerance, or minor imaging abnormalities should prompt consideration of perforation. Early imaging and multidisciplinary review are essential for timely intervention and improved outcomes. Full article

Background: The COVID-19 pandemic has contributed to the increase in maternal mortality due to the direct effects of the viral infection and the indirect effects caused by the overload of health services, and the resulting economic and social crises. This study aims to analyze sociodemographic, gestational, and clinical factors associated with maternal deaths from COVID-19 in Pernambuco between 2020 and 2021. Method: The study included 37 cases (deaths) and 112 controls (survivors). Crude and adjusted odds ratios were estimated using conditional and Firth’s penalized logistic regression models, respectively, to evaluate sociodemographic, gestational, and clinical factors. Results: In the bivariate analysis, the main factors associated with maternal death from COVID-19 were ≤8 years of schooling, the postpartum period, multiparity, oxygen saturation below 95%, obesity, and diabetes mellitus. The presence of fever and cough was associated with a lower probability of death. The independent factors that remained associated with maternal death were the postpartum period (aOR: 80.78; 95% CI: 16.54–394.37), parity ≥ 1 (aOR: 5.74; 95% CI: 1.16–28.22), and oxygen saturation below 95% (aOR: 7.16; 95% CI: 1.37–37.44), with fever acting as a possible protective factor (aOR: 0.08; 95% CI: 0.01–0.42). Factors such as obesity and diabetes were not independent predictors in the final multivariable model. Conclusions: The findings reinforce that maternal death is a multifactorial phenomenon. The relevance of this investigation lies in identifying clinical and obstetric vulnerability profiles in a region heavily impacted by the health crisis. Knowledge gained from past crises contributes to the improvement of public health strategies and clinical management protocols, aiming to mitigate preventable maternal deaths in future public health emergencies. Full article