Access microbiology最新文献

{"title":"Fungal positivity seen in tertiary care hospital during COVID-19 pandemic.","authors":"Ravinder Kaur, Deepti Rawat, Ashish William, Pradeep Kumar Singh, Neelam S S Kandir, Akanksha Sharma","doi":"10.1099/acmi.0.000640.v5","DOIUrl":"10.1099/acmi.0.000640.v5","url":null,"abstract":"<p><p>Coronavirus disease 2019 (COVID-19) pandemic has been prevailing for more than a year, associated with an increased number of opportunistic invasive fungal infections in patients who have been critically ill or immunocompromised. In this retrospective study, details of various clinical specimens received from suspected patients of fungal infections were studied. Fungal cultures were positive in 64% (51 out of 79) of COVID-19-positive patients and 43% (163 out of 381) of COVID-19-negative patients during the second wave of COVID-19 in 2021. Among COVID-19-infected patients, the most commonly isolated fungi were <i>Candida</i> spp. (63%), followed by <i>Aspergillus</i> spp. (15%) and <i>Mucor</i> spp. (6%). The majority of samples that tested positive in COVID-19-infected patients were urine (17% from COVID-19-positive and 83% from COVID-19-negative patients), followed by serum (tested for <i>Aspergillus</i> galactomannan). <i>Candida</i> isolation was observed in 27% (21/79) of urine samples and 15% (12/79) of respiratory samples [bronchoalveolar lavage (BAL), tracheal aspirate, and sputum] from COVID-19-positive patients. <i>Rhizopus arrhizus</i> and <i>Rhizopus homothallicus</i> were isolated from nasal and tissue samples in 6% of COVID-19-positive patients. There was an overall increase in fungal co-isolations during the COVID-19 pandemic (64% in COVID-19-positive and 43% in COVID-19-negative patients), which is a matter of great concern. The correlation of clinical symptomatology and laboratory isolation is important for the diagnosis and effective management of these patients.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11777003/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143070148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights into the genome of Azotobacter sp. strain CWF10, isolated from an agricultural field in Central India.","authors":"Arindam Roy, Anwesha Ghosh, Yash, Prateeksha Mehra, Sumit Roy, Punyasloke Bhadury","doi":"10.1099/acmi.0.000930.v4","DOIUrl":"10.1099/acmi.0.000930.v4","url":null,"abstract":"<p><p><i>Azotobacter</i> sp. strain CWF10, an aerobic gram-negative, oval-shaped and motile bacterium, was isolated from the lateritic agricultural soil of Madhya Pradesh, India. The draft genome of the isolate is 5.7 Mb in size, consisting of 14 contigs with 65.09% G+C content. Average nucleotide identity (94.66%) and digital DNA-DNA hybridization (62%) calculation with the closest reference strains underpin the bacterium as a potential novel species. The bacterium has a plethora of plant growth-promoting genes that point towards the potential ability to enhance available nitrogen and biosynthesis of folic acid, among others. Siderophores such as vibrioferrin and crochelin A are also present in the genome and are known to regulate iron uptake. Overall, mining the genome of <i>Azotobacter</i> sp. strain CWF10 has revealed the potential of this strain for application in regenerative agriculture and sustaining soil health.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12282048/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probiotic potential of riboflavin-overproducing Bacillus subtilis ACU-I163MR and ACU-I11MR, isolated from fermented African locust beans.","authors":"Theresa Awotundun, Afolake Olanbiwoninu","doi":"10.1099/acmi.0.000883.v3","DOIUrl":"10.1099/acmi.0.000883.v3","url":null,"abstract":"<p><p>Riboflavin (vitamin B₂) is a water-soluble compound that plays an important role in multiple cellular functions. This study evaluates the probiotic potential of riboflavin-overproducing <i>Bacillus subtilis</i> strains isolated from fermented African locust beans. After strain improvement, <i>B. subtilis</i> ACU-I11MR and ACU-I163MR were selected due to their higher riboflavin production (0.01905±0.0005 mg l^-1 to 0.0259±0.0077 mg l^-1 and 0.0195±0.0054 mg l^-1 to 0.0267±0.0013 mg l^-1, respectively). Their safety was confirmed through haemolytic assay, antibiotic susceptibility tests and the absence of gelatinase and biogenic amine activity. Probiotic potential was assessed via <i>in vitro</i> assays including resistance to low pH, bile salts, phenol, temperature and NaCl; auto-aggregation; cell hydrophobicity; biofilm formation; antibacterial activity; and enzyme and exopolysaccharide production. Both strains were non-haemolytic and negative for gelatinase and biogenic amine activity. They showed significant viability at pH 2 (survival 85.05; 87.09%), 1% bile salts (survival 88.82; 87.64%) and 0.5% phenol (survival 48.80; 59.52%), respectively. ACU-I11MR was susceptible to 9 out of 12 antibiotics, while ACU-I163MR was 100% susceptible. The strains demonstrated strong cell surface adhesion and auto-aggregation and inhibited several pathogenic bacteria. They produce amylase, protease and exopolysaccharide and thrive under various temperature and NaCl conditions. <i>B. subtilis</i> ACU-I163MR, showing superior probiotic potential, could be a promising candidate for developing riboflavin-enriched <i>Bacillus</i>-fermented functional foods.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12282050/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacterial skin infection caused by a plant pathogen Kosakonia cowanii: identification with the MALDI Biotyper sirius one and susceptibility testing.","authors":"John Merlino, Kiora Pillay, Sophia Rizzo, Sai Rupa Baskar, Daniel Seed, Steven Siarakas, Ravin Hettiarachchi, Genevieve McKew, Timothy Gray","doi":"10.1099/acmi.0.000923.v3","DOIUrl":"10.1099/acmi.0.000923.v3","url":null,"abstract":"<p><p><i>Kosakonia cowanii</i> is a Gram-negative bacillus belonging to the order Enterobacterales. <i>K. cowanii</i> is a plant pathogen; we report the isolation of this organism from a gardening puncture injury from a plant. Pus examined from the site of infection showed the infecting organism as <i>K. cowanii</i> by MALDI-TOF MS Biotyper Sirius One and 16S rRNA analysis. The organism failed to be identified biochemically by the Vitek 2 XL identification system as <i>Kosakonia</i> spp. The Gram-negative bacilli on the system were biochemically identified as <i>Pantoea</i> spp. Difficulties in species identification biochemically suggest that <i>K. cowanii</i> might potentially represent an underestimated opportunistic human pathogen in skin infections associated with plant injuries. The MALDI-TOF MS Biotyper Sirius One software was found to be a fast and reliable identification of the organism. The isolate was found to be susceptible to first-generation cephalosporins, both cefalexin and cefazolin, by disc diffusion and Vitek 2 XL, even though antibiotic breakpoints currently do not exist using European Committee on Antimicrobial Susceptibility Testing or Clinical and Laboratory Standards Institute (CLSI) guidelines for this organism.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12281777/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Protein profile of the Escherichia coli strain, BW25113, exposed to two novel iron-halide compounds: Fe(Hampy)2Cl4 and Fe(Hampy)2Br4.","authors":"Nusrat Abedin, Sarah Wagner, Yukta Sanjay Khalkar, Zulekha Johnson, Biola F Egbowon, Alan J Hargreaves, Anthony J Fitzpatrick, Amanda K Miles, Felix Dafhnis-Calas","doi":"10.1099/acmi.0.000783.v4","DOIUrl":"10.1099/acmi.0.000783.v4","url":null,"abstract":"<p><p>The mortality rate and economic burden of infections caused by antimicrobial-resistant pathogens are increasingly higher. This frustrating scenario emphasizes the urgent need for developing new antimicrobial drugs. We have previously addressed this problem by studying the antimicrobial activity of two novel iron-halide complexes, Fe(Hampy)₂Cl₄ (iron tetrachloride) and Fe(Hampy)₂Br₄ (iron tetrabromide). Both compounds showed bactericidal and antibiofilm activities against bacteria with an antimicrobial resistance phenotype. Herein, we used a proteomic approach to investigate the proteomic profile of bacterial cells previously exposed to both iron-halide complexes. For this study, the <i>Escherichia coli</i> strain, BW25113, was used as a model to facilitate the rapid identification of deregulated proteins. Heat map analysis of the common deregulated proteins highlighted that both complexes caused the downregulation of proteins associated with key metabolic pathways, biofilm formation, cell envelope biogenesis and iron ion binding. In addition, a network study suggested that the most influential proteins of the tetrachloride activity were those involved in the TCA cycle, oxidative phosphorylation, iron ion homeostasis and carbon/secondary metabolism. This protein-protein interaction analysis also hinted that the main drivers of the tetrabromide activity were proteins involved in translation, ribosomal biogenesis and cell motility. The above results strongly suggested how the presence of different halide ligands could be used to generate compounds with potentially different molecular mechanisms. Importantly, the findings of this study can also be used as a reference to compare with the protein profile of bacteria exposed to future variants of the iron-halide complexes.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12282026/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anaerobic HgII reduction is driven by cellular HgII-thiol interactions.","authors":"N C Lavoie, A J Poulain","doi":"10.1099/acmi.0.000932.v3","DOIUrl":"10.1099/acmi.0.000932.v3","url":null,"abstract":"<p><p>Redox reactions play a critical role in determining the availability of mercury species, Hg^II and Hg⁰, to anaerobic microbes responsible for methylating inorganic mercury into toxic monomethylmercury. Some anaerobes also contribute to Hg cycling in methylation hotspots by reducing Hg^II to its gaseous elemental form, Hg⁰. However, their contributions remain poorly quantified due to limited mechanistic insights and the absence of genetic targets. In this study, we investigated the mechanisms of anaerobic Hg^II reduction in the versatile anoxygenic photoheterotroph and fermenter <i>Heliomicrobium modesticaldum</i> Ice1. Given Hg^II strong electrophilic affinity for thiol groups, we hypothesized that cellular thiols are key interaction sites mediating Hg^II reduction. Exposure of <i>H. modesticaldum</i> to the thiol-alkylating agent <i>N</i>-ethylmaleimide (NEM), which irreversibly binds thiols, resulted in a concentration-dependent inhibition of Hg⁰ production during both photoheterotrophy and fermentation. Hg partitioning assays with <i>Escherichia coli</i> cells revealed no significant differences in Hg-cell partitioning in the presence or absence of NEM, suggesting that Hg^II reduction is dependent on intracellular thiol interactions. These findings highlight the importance of thiol-mediated pathways in Heliobacterial Hg^II reduction. Although the exact cellular components remain unidentified, we discuss potential thiol-containing coupling sites that warrant further investigation.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12282025/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial flora of the respiratory tract and skin of artisanal municipal solid waste handlers in Aba, Abia State, Nigeria.","authors":"I W Nwankwo, N C Nwachukwu, E C Onwuchekwa, O C Okamgba, O C Ugbogu","doi":"10.1099/acmi.0.000876.v5","DOIUrl":"10.1099/acmi.0.000876.v5","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Municipal solid waste handling carries occupational risk for waste handlers due to exposure to diverse microorganisms and hazardous substances that cause respiratory and skin infections. A cross-sectional study was carried out, and 150 respondents were recruited using a simple random sampling technique. The sociodemographic characteristics, health-related complaints, health-seeking behaviour and the bacterial and fungal microflora of the respiratory tract and skin of artisanal municipal solid waste handlers and some controls in Aba, Nigeria, were determined using a mixed methods research design, involving the use of interviewer-administered structured questionnaires and conventional culture techniques. We analysed the data using IBM SPSS version 25. The results are presented in tables as frequencies and percentages. The majority of artisanal municipal solid waste handlers in Aba are male (95%). Their mean age is 30 years, and the age group of 21-40 years constitutes the highest proportion (65%) of the workforce. Health-related complaints were higher (95%) among the waste handlers compared to the control subjects (4%). The findings show a high prevalence of respiratory (57%), eye (34%) and skin (87%) complaints among the waste workers, compared to 6%, 0% and 2%, respectively, among the control subjects. Seventy-eight (78%) of the waste handlers indulge in self-medication via over-the-counter (OTC) drugs; 17 (17%) access diagnostic laboratories and only 4 (4%) visit hospitals for treatment, as compared to the control subjects, who recorded 1 (2%) for OTC drugs, 46 (92%) for laboratories and 2 (4 %) for hospitals. Acquisition (15%) and use (3%) of personal protective equipment (PPE) were very low amongst the waste handlers. A total of 704 bacterial isolates and 191 fungal organisms were isolated from the study subjects. Among the waste handlers, the percentage distribution of bacteria was almost the same at both sites: respiratory tract, 241 (49.9%) and skin, 242 (50.1%), compared to the control subjects' respiratory tract, 105 (47.5%) and skin, 116 (52.5%), which showed a slight difference between the sites. &lt;i&gt;S. epidermidis&lt;/i&gt; (24%) and &lt;i&gt;B. cereus&lt;/i&gt; (13%) were predominant in the respiratory tract, whereas &lt;i&gt;S. aureus (29%) and S. epidermidis&lt;/i&gt; (19%) predominated the skin of the waste handlers. Similarly, &lt;i&gt;S. aureus&lt;/i&gt; (34.3%) and &lt;i&gt;B. cereus&lt;/i&gt; (20.9%) were predominant in the respiratory tract, while &lt;i&gt;B. cereus&lt;/i&gt; (37.9%) and &lt;i&gt;S. epidermidis&lt;/i&gt; (18.1%) predominated the skin of the control subjects. &lt;i&gt;Candida&lt;/i&gt; spp. was the most predominant fungus in the respiratory tract (81.4%) and skin (42.9%) of the waste handlers, as well as in the respiratory tract (85%) and skin (78%) of the controls. The presence of the isolated bacteria and fungi in increased proportions in the waste handlers may be attributed to occupational exposure through direct contact with waste, inhalation of organic dust laden with biological agents and","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12281963/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Peribacillus simplex and Klebsiella pneumoniae responsible for pyonephrosis with secondary psoas abscess: a case report.","authors":"Zakaria Malihy, Tilila Abassor, Yassine Ben Lahlou, Elmostafa Benaissa, Mariama Chadli","doi":"10.1099/acmi.0.000911.v3","DOIUrl":"10.1099/acmi.0.000911.v3","url":null,"abstract":"<p><p>Bacterial urinary tract infections (UTIs) are common, ranging from benign cystitis to complicated pyelonephritis, which can lead to severe complications such as pyonephrosis and sepsis. Pyonephrosis, characterized by the presence of pus in the renal cavities, often requires urgent urological intervention. We report a unique case of pyonephrosis with a psoas abscess caused by <i>Klebsiella pneumoniae</i> and <i>Peribacillus simplex</i> in a 64-year-old diabetic female patient. This is the first case of pyonephrosis caused by <i>P. simplex</i>. The patient presented with acute right lumbar pain, fever and altered consciousness. Imaging revealed severe right hydronephrosis, pyonephrosis and a perirenal phlegmon infiltrating the psoas with abscesses. Surgical drainage and nephrectomy were performed. Microbiological and proteomic analyses identified <i>K. pneumoniae</i> and <i>P. simplex</i>. This case highlights the importance of considering environmental bacteria like <i>P. simplex</i> in severe infections and ensuring rigorous protocols to avoid contamination. Successful management of pyonephrosis relies on prompt surgical drainage and appropriate antibiotic therapy based on culture results.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11729731/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142985956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pancreatic tuberculosis revealed by a mass with neoplastic appearance: a case report.","authors":"","doi":"10.1099/acmi.0.000907.v3","DOIUrl":"10.1099/acmi.0.000907.v3","url":null,"abstract":"<p><p><b>Introduction.</b> Pancreatic tuberculosis is an extremely rare form of extrapulmonary tuberculosis. This condition can be challenging to diagnose due to its rarity, nonspecific symptoms and radiological features that may mimic a neoplastic origin. <b>Case report.</b> A 46-year-old immunocompetent patient with no past history of tuberculosis exposure presented with spontaneously resolving jaundice over the past month, accompanied by nonspecific fever episodes and general fatigue with no other associated digestive symptoms. Abdominal computed tomography (CT) and magnetic resonance imaging (MRI) scans revealed a poorly defined, partially necrotic mass in the pancreatic head with heterogeneous hypodensity and enhancement after contrast injection. Additionally, there were nodal and hilar macro-nodal lesions with necrotic appearances, as well as peripancreatic lymphadenopathy. The patient was scheduled for an endoscopic ultrasound (EUS) examination, which revealed the presence of a heterogeneous lesion with areas of necrosis in the posterosuperior aspect of the head and isthmus of the pancreas, accompanied by perilesional and coeliac lymphadenopathies with necrotic centres. EUS-guided tissue sampling allowed the diagnosis of pancreatic tuberculosis, with both histological examination and GeneXpert MTB/RIF testing rapidly positive for <i>Mycobacterium tuberculosis</i>, followed by culture on solid Loewenstein-Jensen medium. The patient responded well to antitubercular chemotherapy. <b>Conclusion.</b> Pancreatic tuberculosis, though rare, should be considered in cases of pancreatic masses, especially in endemic regions. Tissue samples with necrosis should be tested for <i>M. tuberculosis</i> using GeneXpert and Loewenstein-Jensen culture. This work highlights the GeneXpert MTB/RIF test as highly sensitive, specific and fast, making it ideal for diagnosing extrapulmonary tuberculosis, particularly when smear results are negative.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12281965/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunogenicity of bivalent versus monovalent mRNA booster vaccination among adult paramedics in Canada who had received three prior mRNA wild-type doses.","authors":"Michael Asamoah-Boaheng, David M Goldfarb, Iryna Kayda, Justin Yap, Tracy Kirkham, Mohammad Ehsanul Karim, Paul Demers, Jeffrey M Copp, Brian Grunau","doi":"10.1099/acmi.0.000791.v3","DOIUrl":"10.1099/acmi.0.000791.v3","url":null,"abstract":"<p><p><b>Introduction.</b> Comparative immunogenicity from different mRNA booster vaccines (directed at WT, BA.1 or BA.4/5 antigens) remains unclear. <b>Methods.</b> We included blood samples from adult paramedics who received three mRNA WT-directed vaccines plus a fourth dose of the following: (1) WT monovalent, (2) Moderna BA.1-WT bivalent or (3) Pfizer BA.4/5 WT bivalent vaccine. The primary outcome was angiotensin-converting enzyme 2 (ACE2) inhibition to BA.4/5 antigen. We used optimal pair matching (using age, sex-at-birth, preceding SARS-CoV-2 infection and fourth vaccine-to-blood collection interval) to create balanced groups to individually compare each vaccine type to each other vaccine (overall, within subgroups defined by SARS-CoV-2 infection and after combining BA.1 and BA.4/5 cases). We compared outcomes with the Wilcoxon matched-pairs signed rank test. <b>Results.</b> Overall, 158 paramedics (mean age 45 years) were included. ACE2 inhibition was higher for BA.1 compared to WT (<i>P</i>=0.002); however, no difference was detected between BA.4/5 vs. WT or BA.1 vs. BA.4/5. Among cases with preceding SARS-CoV-2, there were no detected between-group differences. Among cases without preceding SARS-CoV-2, the only detected difference was BA.1>WT (<i>P</i>=0.003). BA.1 and BA.4/5 cases combined had higher ACE2 inhibition than WT (<i>P</i>=0.003). <b>Conclusion.</b> Omicron-directed vaccines appear to improve Omicron-specific immunogenicity; however, this appears limited to SARS-CoV-2-naive individuals.</p>","PeriodicalId":94366,"journal":{"name":"Access microbiology","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11728694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142980914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}