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PubMed1979

Etiology, manifestations and therapy of acute epididymitis: prospective study of 50 cases.

There were 50 patients with acute epididymitis who were evaluated prospectively by history, examination and microbiologic studies, including cultures for aerobes, anaerobes, Neisseria gonorrhoeae, Chlamydia trachomatis and Ureaplasma urealyticum. Escherichia coli was the predominant pathogen isolated from the urine of men more than 35 years old, while Chlamydia trachomatis and Neisseria gonorrhoeae were the predominant pathogens isolated from the urethra of men less than 35 years old. The etiologic role of Escherichia coli and Chlamydia trachomatis was confirmed by isolation from epididymal aspirates from a high proportion of men with positive urine or urethral cultures for these agents. Chlamydia trachomatis epididymitis accounted for two-thirds of idiopathic epididymitis in young men and often was associated with oligospermia. Of 9 female sexual partners of men with Chlamydia trachomatis infection 6 had antibody to Chlamydia trachomatis, of whom 2 had positive cervical cultures for this organism and 2 others had non-gonococcal pelvic inflammatory disease. Antibiotic therapy with tetracycline was effective for the treatment of men with Chlamydia trachomatis epididymitis and should be offered to the female sex partners.

Adolescent↗
PubMed2026

Genomic signatures associated with epidemiologically defined high-risk pathogenic Escherichia coli isolates identified by interpretable machine learning.

Pathogenic Escherichia coli is a major cause of foodborne illness worldwide and includes strains capable of causing severe disease. To establish a genome-informed framework for foodborne outbreak surveillance, we analyzed 1,029 E. coli isolates from clinical, food, livestock, and environmental sources using whole-genome sequencing. Pathogenic isolates obtained from human clinical cases or linked to documented outbreaks were classified as epidemiologically defined high-risk (EpiHR), whereas the remaining pathogenic isolates were classified as non-EpiHR. Virulence-associated genomic features were extracted using a bioinformatics pipeline, and four machine learning (ML) algorithms, including gradient boosting machine, random forest (RF), and support vector machines with linear and radial basis function kernels, were evaluated. Among them, the RF model showed the best performance, achieving an area under the curve (AUC) of 0.98 and accuracy of 0.93 in 10-fold cross-validation. Additional leave-one-group-out validation showed retained discrimination across held-out sequence types and serotypes, although performance was reduced when isolates were grouped by isolation source. Evaluation using an independent test dataset of 1,908 publicly available pathogenic E. coli genomes showed an AUC of 0.97 and a sensitivity of 0.98. Feature importance analysis using Shapley additive explanations identified influential predictive features, including traT, etpB, and enterotoxin-associated genes. A reduced 10-feature model achieved an AUC of 0.79 in the independent test dataset, supporting its exploratory use for future simplified screening approaches. These results indicate that genome-based ML provides a sensitive framework for surveillance-oriented prioritization of EpiHR pathogenic E. coli isolates, with model predictions interpreted together with epidemiological information.

Escherichia coli↗
PubMed1975

Antibiograms of pathogenic bacteria isolated from laboratory animals.

Study of antibiotic sensitivity patterns of 178 bacterial isolants from laboratory animals revealed that these bacteria in general were sensitive to many commonly used antibiotics; however, there were notable exceptions. This report presents current antibiotic sensitivity patterns of most gram-negative and gram-positive bacterial pathogens common to laboratory animals.

Ampicillin↗
PubMed1977

Imferon agar: improved medium for isolation of pathogenic Neisseria.

Imferon, an iron-dextran complex, enhances the growth of Neisseria gonorrhoeae and N. meningitidis. The use of Imferon as a replacement for ferric nitrate, in a defined supplement for GC agar significantly increased the average colony sizes of both gonococci and meningococci. In comparison with Thayer-Martin medium, Imferon agar increased the speed and rate of isolation of gonococci from clinical specimens.

Agar↗
PubMed1976

Pathogenic rotaviruses isolated from pigs and calves.

Rotavirus is commonly isolated from diarrhoeic calves and pigs. Bacterium-free faecal filtrates containing rotavirus from five different outbreaks of disease in calves all caused diarrhoea and clinical illness in gnotobiotic calves and five different isolates from pigs were inoculated into gnotobiotic pigs with similar results. The author was unsuccessful in finding an avirulent strain although one of the calf isolates was from a non-diarrhoeic calf. The laboratory strain of calf virus retained its virulence after being passaged seven times in gnotobiotic calves, which included sucrose density gradient purification on two occasions. The calf tissue culture-adapted virus retained its virulence. Rotavirus isolates from humans, calves, pigs and foals were infectious to pigs. Although sharing a common antigen the viruses were separable according to host infectivity, virulence and neutralizing antigens. In both calves and pigs the main lesion was loss of the epithelial cell of the small intestine and stunting of villi. Passive protection of the calf and pig was poor. Circulating antibody was not protective and although high levels of clolostral antibody in the gut lumen at the time of infection protected calves clinically, the antibody level secreted in milk declined 10-fold 48 hours after parturition. Frequently other viruses are found together with rotavirus in cases of diarrhoea. Their role is being investigated.

Animals↗
PubMed1978

An overview of results of world-wide clinical trials with cefadroxil.

Céfadroxil, a new semisynthetic oral cephalosporin, is absorbed similarly by fasted and non-fasted subjects, produces sustained serum levels and is eliminated at a relatively slow rate. These pharmacokinetic properties permit less frequent and more convenient dosage scheduling than cephalexin and cephradine and consequently greater patient compliance. Cefadroxil was evaluated for safety in 1051 patients and for efficacy in 1030 patients. Overall it achieved a 91.8% rate of clinical success resulting from 881 complete cures and sixty-five clinical cures. Among 363 patients with respiratory tract infections and 471 patients with genito-urinary tract infections, cefadroxil treatment produced 97.5% and 84.5% clinical success, respectively. In the remaining infectious diseases treated, cefadroxil therapy resulted in 99.0% clinical success. Cefadroxil eradicated 87% of 1110 pathogens isolated, among which the most predominant pathogens were Staphylococcus aureus, beta-haemolytic streptococci, Streptococcus pneumoniae, Escherichia coli and Proteus mirabilis. Drug-related side-effects were reported in 7.2% of the patients.

Adolescent↗
PubMedDate not supplied

[Mark's disease: V. Experimental behavior of 3 isolates taken place in the country].

Three experiments were designed to determine the parameters of virus infection, antibodies and mortality with three different MD isolates inoculated in one day old birds from commercial origin. The animals were divided in three inoculated lots (1-2-3) and three control groups (4-1, 4-2, 4-3) and were followed weekly from hatching through 17 weeks. The former were inoculated respectivelly with FOV-6, FCV-8 and FCV-9. Each day old bird received between 50-75 FPU/bird by I.P. route. Samples were taken from circulating blood of five birds by cardiac puncture with an heparinized syringe (20 U/ml), were centrifuged and the white cells inoculated to 5-15 four day old embryos by yolk salk route for virus detection; plasma was assayed by immunodiffusion against MD antigen in order to detect precipitating antibodies, and mortality was recorded after microscopical examination. Infection appeared to persist indefinitelly in the host chicken flock and coexist with (100%) precipiting antibodies, (Fig. 1-2-3). First virus isolation was accomplished after 4 weeks post-inoculation and the 100% porcentage of antibodies, was found only 1-3 weeks after the first peak of viraemia. With the most pathogenic isolate FCV-6 (ig. 1) the antibody response was significantly delayed. Maternal antibodies decreased more rapidly in inoculated than in control birds. Accumulative mortality showed isolate FCV-6 and FCV-8 as pathogenic strains and FCV-9 strain as less pathogenic. Mortality begun 1-3 weeks after the first peak of virus detection in the flock, independently of the pathogenic pattern of the isolate, but frecuencies of death were markedly different.

Animals↗
PubMed1978

Characterization of an apparently nononcogenic Marek's disease virus.

A new isolate of Marek's disease virus (MDV) was described. This virus, SB, and a clone, SB-1, differed from pathogenic isolates in in vitro growth characteristics as described for other apathogenic isolates. Serologically, as with other apathogenic isolates, SB could be distinguished from pathogenic MDV and the avirulent turkey herpesvirus. SB failed to induce lesions characteristic of Marek's disease (MD) during a 6- to 11-week experimental period. Also, SB was nononcogenic in immunosuppressed chickens or in chickens inoculated with this virus in ovo. However, under those conditions, SB caused a cytolytic infection. The term "nononcogenic" rather than "apopathogenic" was therefore proposed to classify this and similar isolates. SB-1 protected chickens against challenge with either virulent MDV or the non-virus-producing MD tumor transplant, JMV. Possible mechanisms of protection are discussed.

Animals↗
PubMed2026

Patterns of antimicrobial resistance genes in pathogens across One Health sectors in Ireland: an in silico approach.

As part of a rapid risk assessment, an in silico approach was used to detect antimicrobial resistance (AMR) in pathogenic isolates from humans, animals, and the environment. A total of 11,670 genomic data sets were retrieved from the NCBI Pathogen Detection system for Ireland, which represented 47 pathogenic species, including Salmonella enterica, Escherichia coli/Shigella spp., Staphylococcus aureus, Klebsiella pneumoniae, and Enterococcus faecium. Identifying the most critical pathogenic strains over time is essential, as these organisms significantly contribute to mortality, morbidity, and hospitalization. The analysis identified 799 antimicrobial resistance genes (ARGs), including their allelic diversity, 117 plasmid replicons, and 274 virulence factors. Several critical ARGs, particularly those conferring resistance to beta-lactams, aminoglycosides, quinolones, and colistin, were common across isolates originating from human, animal, and environmental sources, suggesting shared resistance profiles across One Health sectors. Klebsiella pneumoniae, E. coli/Shigella spp., S. enterica, and S. aureus were the dominant hosts of these ARGs and associated mobile genetic elements. Increasing resistance across major antibiotic classes aligned with trends reported across other European countries. This study provides a national-scale in silico comparison of AMR across pathogens and One Health sectors using publicly available genomic data. The findings help reinforce Ireland's AMR surveillance by showing which resistance genes are present and how they spread across critical pathogens in humans, animals, and the environment. These findings highlight the urgent need for improved antibiotic stewardship and integrated One Health surveillance to limit the emergence and spread of AMR.IMPORTANCEAntimicrobial resistance (AMR) is a growing threat to human, animal, and environmental health. This study used publicly available genomic data to identify antimicrobial resistance genes (ARGs) in key bacterial pathogens circulating in Ireland. By analyzing over 11,000 genomes from humans, animals, and the environment, we found that several dangerous resistance genes, including those against last-resort antibiotics, were widespread across different sources. The study highlights which bacteria and resistance genes are most critical and how they may spread between humans, animals, and the environment. These insights provide a national snapshot of AMR, supporting more effective monitoring and prevention strategies. By revealing patterns of resistance and modes of transmission, our findings underscore the importance of coordinated antibiotic stewardship and One Health approaches to slow the emergence and spread of resistant infections, protecting public health and ensuring antibiotics remain effective.

Humans↗
PubMed2026

A Decade of Achievements and Future Directions in Global Antimicrobial Resistance Surveillance System in Korea (Kor-GLASS).

OBJECTIVES: To comprehensively evaluate the 10-year operational outcomes (2016-2025) Global Antimicrobial Resistance Surveillance System in Korea (Kor-GLASS), assess its public health significance for national stewardship and global surveillance, and propose strategies for future development. METHODS: The study described the operational framework of Kor-GLASS, including its strain collection, analysis, and quality control systems, based on surveillance data. It analyzed resistance trends among key bloodstream pathogen isolates collected from 2016 to 2024 and evaluated major achievements, including alignment with the World Health Organization (WHO)'s Global Antimicrobial Resistance Surveillance System (GLASS), integration with the Emerging Antimicrobial Resistance Reporting (EAR) system, and activities as a WHO Collaborating Centre. RESULTS: Kor-GLASS operates on a foundation of standardized, isolate-based surveillance supported by an independent quality management system that complies with WHO GLASS standards. In alignment with the strategic direction of WHO GLASS, the surveillance scope has progressively expanded in terms of catchment areas, target pathogens, specimen types, and antimicrobial panels. From 2016 to 2024, a total of 116,955 clinical isolates were collected and analyzed through the network of collection and analysis centers. This has enabled the continuous generation of nationally representative antimicrobial resistance (AMR) data from general hospitals. The accumulated surveillance data provide fundamental evidence for tracking long-term resistance trends and elucidating the molecular epidemiological characteristics of key pathogens. These outcomes are disseminated through the publication of the "National Antimicrobial Resistance Surveillance Annual Report" and data submissions to WHO GLASS and GLASS-EAR, thereby supporting both national and global AMR surveillance efforts. Furthermore, Kor-GLASS has strengthened international surveillance and One Health collaboration capacities through its designation and redesignation as a WHO Collaborating Centre for AMR Surveillance. CONCLUSIONS: Over the past decade, Kor-GLASS has served as the cornerstone of national antimicrobial resistance surveillance, providing evidence to inform policy and supporting global surveillance systems. Moving forward, Kor-GLASS is expected to evolve into a pivotal national AMR surveillance system through the introduction of whole-genome sequencing and stronger integration with national antimicrobial consumption surveillance.

Anti-bacterial agents↗
PubMed1979

Role of viruses in febrile convulsions.

A disseminated viral illness was demonstrated by isolating a virus from the CSF, blood or urine in 27% of 73 children who were admitted to hospital after a first febrile convulsion. However, a viral aetiology could be implicated for 86% of the children after combining results of tissue culture, electron microscopy, mouse inoculation, complement fixation tests, and interferon assay. Parallel bacterial cultures showed a possible pathogen in 29% of children, but in only 4% was the pathogen isolated from the CSF, blood, or urine. No correlation was found between the nature of the pathogen (or evidence of its dissemination) and the severity of the convulsion, degree of fever, CSF protein, CSF white cells, or the WBC. The results suggest that a febrile convulsion could be a response to invasion of the blood stream or central nervous system by a micro-organism which is usually a virus. Invasion may be of such brief duration that successful isolation of the virus from the blood, CSF, or urine in not more commonly achieved.

Child↗
PubMed1978

p-nitrophenylglycerol--a superior antiswarming agent for isolating and identifying pathogens from clinical material.

The antiswarming agent p-nitrophenylglycerol (PNPG) has been found invaluable for the recognition and isolation of pathogenic bacteria from specimens contaminated with swarming strains of Proteus spp. PNPG is cheap, stable and non-toxic. All strains tested grew well in its presence and produced characteristic morphology. PNPG was without effect on the results of a variety of identification tests performed directly on colonies from media containing PNPG. This permitted identification without the need for further subculture.

Bacteria↗
PubMed1978

Incidence of infections with Salmonella enteritidis serotypes in Black and Indian children. A 16-year survey.

A 16-year survey (1960--1975) of Salmonella infections other than typhoid fever in Black and Indian children admitted to King Edward VIII Hospital, Durban, is reported. The 3,393 patients yielded 3,688 Salmonella enteritidis serotypes, mainly typhimurium, johannesburg/duval, manhattan, enteritidis, and senftenberg. Organisms were isolated from one or more of the following: stool, urine, blood, cerebrospinal fluid, liver, sputum, subcutaneous tissue, ear and bone. Patients' ages varied from 1 day to 12 years, with a median age of 8 months. The high incidence of malnutrition, other debilitating diseases and multiple pathogens isolated from many of the patients precluded firm decisions as to the role played by most salmonellae as contributory factors or causes of death.

Black or African American↗
PubMedDate not supplied

Comparative studies of cefoxitin and cephalothin: an overview.

A comparative study of the efficacy and safety of cefoxitin and cephalothin in the treatment of serious infections was carried out by 21 investigators. A total of 320 patients were treated with cefoxitin, and 276 patients were treated with cephalothin. In each group 50% of patients could be evaluated. Patients were randomly allocated to groups in open fashion, and final analysis showed that the groups were comparable in terms of sex, age, severity of illness, and duration of therapy. The majority of pathogens isolated were susceptible to both agents, although 13% of gram-negative bacilli and anaerobes were susceptible to cefoxitin alone. The overall percentage of patients cured or improved by cephalothin was 93%; for cefoxitin the proportion was 91%. No statistical differences in response by type of organism or site of infection were shown. Cefoxitin was effective in treating infections and in eradicating the pathogenic bacteria. Cefoxitin was as well tolerated as cephalothin and produced no more adverse reactions or abnormal laboratory findings than did cephalothin. The results of this study demonstrate that cefoxitin is as effective in achieving bacteriologic and clinical cures as is cephalothin and also is effective in treatment of infections due to cephalothin-resistant bacteria.

Bacterial Infections↗
PubMed2026

Surface architecture of the bacterial envelope determines phage adsorption route in pathogenic Escherichia coli O157:H7.

UNLABELLED: The outermost surface layers of Gram-negative bacteria determine phage access to terminal receptors, yet their genetic basis has been mapped almost exclusively in laboratory strains that lack them. Here we apply genome-wide RB-TnSeq fitness profiling to four Escherichia coli O157:H7 strains from distinct phylogenetic clades sharing the O157 O-antigen, using 38 phages with terminal receptors previously mapped in E. coli K-12 strain. RB-TnSeq fitness landscapes across all four pathogenic backgrounds were mostly similar, and dominated by surface-associated loci, including the gfc-etk group 4 capsule operon, O-antigen biosynthesis genes, LPS core assembly genes and outer membrane proteins. Disruption of gfc-etk abolished infection in 11 genetically diverse myoviruses, establishing the O-antigen capsule as a widespread required primary recognition substrate. O-antigen loci generated two classes of fitness score patterns. For 10 phages, disruption increased infectivity, indicating it is a barrier to receptor access; for 3 others, disruption abolished infectivity, demonstrating it can also be a primary recognition substrate. Outer membrane protein receptor identity was conserved across laboratory and pathogenic backgrounds, with the same proteins recognized in both K-12 and O157:H7, while glycan layer state determines whether these receptors are reached. These results demonstrate that outer surface glycan layers can act as primary and optional recognition substrates for phage infection, or as physical barriers preventing terminal receptor access. Extending the ability to probe phage-targeted receptors beyond outer membrane proteins provides a framework for incorporating glycan layer state into predictive models of phage-host interactions. IMPORTANCE: Bacteriophage-based interventions for controlling Escherichia coli O157:H7, a major foodborne pathogen responsible for tens of thousands of illnesses annually in the United States, require a mechanistic understanding of the factors governing strain-level susceptibility. Predictive frameworks developed in laboratory model strains lacking O-antigen and capsular polysaccharides can map the terminal protein receptors that phages bind, but are currently limited in their ability to determine whether those receptors are accessible in pathogenic isolates carrying full outer surface complexity. This study provides the first genome-scale, functional genetic map of phage susceptibility determinants in O157:H7 and demonstrates that the state of the outer surface layers, specifically the O-antigen and the gfc-etk capsule, determines whether phages can reach conserved terminal receptors. This finding explains differences in phage susceptibility between strains sharing nearly identical gene content, and identifies the molecular layers that must be characterized to predict phage host interaction in pathogenic E. coli backgrounds.

Journal Article↗
PubMed1979

Comparative study of erythromycin, amoxicillin and ampicillin antimicrobial activity against human respiratory tract pathogens.

An in vitro test system was used to compare the antimicrobial activity of erythromycin, amoxicillin and ampicillin against respiratory tract pathogens isolated from man. The minimum inhibitory concentrations (MICs) of fresh clinical isolates of Streptoccus pyogenes, Streptocuccus pneumoniae, Staphylococcus aureus and Haemophilus influenzae to the macrolide and penicillins ranged between 0.01 and 0.9 microgram/ml. The microbes were exposed to each antibiotic for approximately 3 h at 1x,2x and 5x the relevant MIC. Irreversible surface defects and intracellular lesions were resolved by scanning and transmission electron microscopy in all antibiotic-treated bacterial species, irrespective of the antimicrobial used. In each case, inhibition of growth was recorded by turbometric assay; no significant difference was observed among the declining slopes of post-dosing growth curves for either erythromycin-, amoxicillin- or ampicillin-treated pathogens. The experimental observations show that the onset of antimicrobial activity and the bactericidal effectiveness of equipotent concentrations of erythromycin, amoxicillin and ampicillin were comparable in this study. The results complement previous clinical, bacteriologic and ultrastructure studies in vivo and demonstrate the contribution of the combined in vivo/in vitro study design for better understanding of antimicrobial activity in human respiratory tract infections.

Amoxicillin↗