Research Articles (Medical Microbiology)

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Modifiable risk factors for anemia in pregnancy : an umbrella review of systematic reviews and meta-analyses
Dagne, Woldeteklehaymanot Kassahun; Shiferaw, Mulu; Gedfie, Solomon; Jemal, Abdu; Gashaw, Muluken; Kumie, Getinet; Bazezew, Alembante; Sisay, Assefa Legesse; Abebe, Wagaw; Nigatie, Marye; Misganaw, Tadesse; Asmare, Zelalem; Getachew, Ermias; Gashaw, Yalewayker; Ashagre, Agenagnew; Tefera, Zewdu; Alemu, Bewuketu Belete; Tamrat, Ephrem; Kassanew, Brhanu; Dejazmach, Zelalem; Reta, Melese Abate (BioMed Central, 2026-01)
BACKGROUND : Anemia during pregnancy affects more than one-third of women globally, with the heaviest burden in low- and middle-income countries. It contributes substantially to maternal morbidity, adverse birth outcomes, and increased neonatal mortality. Despite extensive research, there remains a lack of comprehensive and up-to-date synthesis on modifiable determinants to guide effective, targeted interventions. This umbrella review aimed to consolidate evidence from systematic reviews and meta-analyses on modifiable risk factors associated with anemia in pregnancy. METHODS : A systematic search was conducted across PubMed, Scopus, ScienceDirect, Epistemonikos, Hinari, Google Scholar, and the Cochrane Library. Search terms combined controlled vocabulary and free-text keywords including anemia, hemoglobin, iron deficiency, determinants, pregnant women, systematic review, and meta-analysis. Boolean operators (OR/AND) were applied, and the search was limited to English-language publications from 2014 to 2024. Eligible studies included systematic reviews and meta-analyses examining risk factors for anemia among pregnant women. Methodological quality was assessed using the Joanna Briggs Institute (JBI) critical appraisal tool, and synthesis followed JBI guidance to ensure rigor and transparency. Certainty of evidence assessed using GRADE. RESULTS : Of 13,348 records identified, 10 systematic reviews and meta-analyses were included. The synthesis highlighted several modifiable risk factors. Nutritional determinants included low dietary diversity (RR = 2.38–3.59), poor dietary practices (AOR = 1.63–2.97), and inadequate iron/folic acid supplementation (AOR = 1.38–1.82). Maternal health conditions, particularly intestinal parasite infections (AOR = 2.18–4.34) and malaria (AOR = 1.94–11.19), showed strong associations. Sociodemographic risks included low maternal education (AOR = 1.34–2.04), short birth intervals (< 24 months; AOR = 1.27–2.84), adolescent pregnancy (AOR = 2.60), large family size (AOR = 1.58–1.95), and rural residence (RR = 1.56). Limited healthcare access, especially lack of antenatal care (AOR = 1.36–2.02), further increased risk. Considerable heterogeneity (I²=0–94.5%) and low-to-moderate certainty ratings (GRADE) suggest variability across settings and highlight context dependence. CONCLUSIONS : Anemia during pregnancy arises from multiple modifiable factors, including poor nutrition, low dietary diversity, adolescent pregnancy, and infections like malaria and intestinal parasites. This umbrella review highlights the importance of developing context-specific interventions and implementing multisectoral policies that integrate nutrition and infection-control strategies to reduce the global burden of maternal anemia.
Reply to Datta, “Is static or cidal antibiotic falsifiable?”
Spellberg, Brad; Wald-Dickler, Noah; Holtom, Paul; Meyer-Sautter, Pascal; Camp, Austin; Diaz Diaz, Alejandro; Buhamad, Ranya; Meza Vazquez, Ali Sebastian; Aguirre-Garcia, Gloria Mayela; Stanton, Matthew; Butler-Wu, Susan M.; Chiu, Isabelle; Ergenc, Zeynep; Bhoojhawon, Guru; Murri, Rita; Maraolo, Alberto Enrico; Cabanilla, Gabriela; Riccardi, Niccolò; Tshisevhe, Vhudzani; Behenna, Curtis; Williams, Karen S.; Kufel, Wesley D.; Wojciaczyk, Natalia; Pimentel, Bernardo Vidal; Muyidi,, Ahmed; Costa, Rodrigo P.L.; Motta, Fabrizio; Bortolussi-Courval, Émilie; Lee, Todd C.; McDonald, Emily G.; Ghanem, Bassam; Nelson, Zachary (American Society for Microbiology, 2025-11)
We would like to thank Dr. Datta for his interest in our article. Dr. Datta wishes to defend the static vs. cidal antibiotic model against “absolutist framing.” He invokes “mono-parametric” assays like “MBC/MIC ratios or…reactive oxygen species generation” to suggest that in vitro static vs. cidal phenomenology may be phenotypically real.
Whole-genome sequencing for surveillance of Salmonella at a public health institution in South Africa
Smith, Anthony Marius; Sekwadi, Phuti; Ngomane, Hlengiwe M.; Disenyeng, Bolele; Erasmus, Linda K.; Thomas, Juno; Bogoshi, Dineo; Smouse, Shannon L.; Tau, Nomsa P. (AOSIS, 2025-12-09)
BACKGROUND : Whole-genome sequencing (WGS) is transforming communicable disease surveillance globally. The National Institute for Communicable Diseases, South Africa, participates in national laboratory-based surveillance for human isolates of Salmonella. OBJECTIVE : This study was to investigate human Salmonella isolates from South Africa, 2020–2023, using WGS analysis. METHODS : WGS was performed using Illumina NextSeq Technology. Data were analysed using multiple bioinformatics tools, including those available at the Center for Genomic Epidemiology, Pathogenwatch and EnteroBase. Data analysis allowed for identification and characterisation of isolates. Core-genome multilocus sequence typing was used to investigate the phylogeny of isolates. RESULTS : Of the 8006 isolates of Salmonella that were analysed using WGS, 130 distinctive serovars and subspecies were identified. Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) (4271/8006; 53.3%) and Salmonella Typhimurium (1430/8006; 17.9%) were the most prevalent serovars, accounting for 71.2% of all isolates. This was followed by Salmonella Typhi (482/8006; 6.0%). Sixteen per cent (1288/8006) of isolates showed the presence of antimicrobial resistance (AMR) determinants associated with ≥ 2 classes of antimicrobials. Salmonella Isangi (167/8006; 2.1%) showed the highest prevalence of AMR, with most isolates (159/167; 95.2%) showing AMR determinants associated with ≥ 7 classes of antimicrobials. Core-genome multilocus sequence typing was used to confirm several suspected clusters and outbreaks and identified additional cryptic or unreported clusters and outbreaks. Investigation of clusters and outbreaks mostly involved Salmonella Enteritidis and Salmonella Typhi. CONCLUSION : The implementation of WGS has enabled genomic surveillance of Salmonella, which allows for enhanced characterisation and AMR determination of isolates and identification of clusters and outbreaks, which informs targeted public health investigation and response. What this study adds: This study describes the population structure of Salmonella isolated from humans in South Africa and hugely contributes to the available Salmonella WGS data from Africa.
A retrospective analysis of uropathogens isolated and antimicrobial susceptibility patterns at a regional hospital in North West province, South Africa
Teixeira, Miguel J.; Pretorius, Vian; Hunt, Robert C.J.G.; Morar, Sanam; Colloty, Jamie; Radebe, Caleb M.; Morar, Rajen (AOSIS, 2025-11-30)
BACKGROUND : Urinary tract infections are among the most common infections affecting the general population. Their high incidence, as well as frequent antimicrobial use, contribute significantly to the development of antimicrobial resistance (AMR). OBJECTIVE : To determine the profile and prevalence of uropathogens isolated from urine specimens at a regional hospital and assess susceptibility patterns to commonly used antimicrobials recommended by the National Essential Medicines List (NEML). METHODS : This was a retrospective evaluation of laboratory reports for all urine specimens submitted between 01 January 2020 and 31 December 2023. RESULTS : The most frequently cultured organisms were Escherichia coli (n = 1481; 42%); Klebsiella pneumoniae (n = 568; 16%); Enterococcus faecalis (n = 249; 7%); Proteus mirabilis (n = 229; 7%), Enterobacter cloacae (n = 137; 4%), and Candida albicans (n = 119; 3%). Escherichia coli maintained high sensitivity to antimicrobials such as nitrofurantoin (92.2%) and gentamicin (90.6%), whilst K. pneumoniae had decreased sensitivities of 40% and 77%, respectively. Cumulative sensitivities of commonly used first-line antimicrobials showed low rates of susceptibility to ciprofloxacin (77%), nitrofurantoin (67%), and amoxicillin/clavulanate (68.7%). CONCLUSION : Escherichia coli was the most commonly identified isolate and remains sensitive to nitrofurantoin. It was, however, resistant to ciprofloxacin, amoxicillin/clavulanate, and trimethoprim sulfamethoxazole, as were all the other Gram-negative organisms. These sensitivity patterns do not align with the antimicrobials recommended in the current NEML guidelines, and highlight the need for targeted therapy and interventions. What this study adds: This retrospective analysis identifies predominant uropathogens’ updated antimicrobial susceptibility profiles, some of which misalign with NEML guidelines. Insights will guide targeted antimicrobial stewardship, empiric therapy, and local surveillance to curb AMR.
Lactobacillus-rich cervicovaginal microbiome associated with lower BV, HPV, and cytology outcomes in women
Osei Sekyere, John; Trama, Jason; Adelson, Martin; Trikannad, Charulata; DiBlasi, Desiree; Schuster, Rachel; Yang, Jing Jing; Mordechai, Eli (Elsevier, 2025-10-17)
The cervicovaginal microbiome modulates susceptibility to bacterial vaginosis (BV), high-risk human papillomavirus (hrHPV) infection, and epithelial cell abnormalities that precede cervical cancer. We retrospectively analyzed 15 607 qPCR-profiled cervicovaginal specimens from U.S. women (ages 14–95; 32 states) and integrated microbiome abundances, hrHPV genotyping, Pap-cytology, and demographics. BV was present in 53% and hrHPV in 11% of samples. Lactobacillus crispatus, L. gasseri, and L. jensenii were enriched in BV-negative and cytologically normal (NILM) samples, whereas L. iners and BV-associated anaerobes co-occurred with hrHPV and abnormal cytology. Machine-learning models confirmed age, hrHPV status, and L. crispatus abundance as the strongest multivariate predictors of BV and cytological outcomes (BV AUROC ≈0.97). Interaction analyses revealed synergistic associations between specific hrHPV genotypes and Gardnerella/Fannyhessea that further increased cytological risk. These findings underscore the clinical value of microbiome profiling and support probiotic strategies that promote protective Lactobacillus communities to reduce BV and hrHPV-related cervical pathology.
Prevalence of colistin resistance in multidrug-resistant Klebsiella pneumoniae recovered from clinical samples in Africa
Gashaw, Yalewayker; Asmare, Zelalem; Sisay, Asefa; Getatachew, Ermias; Gedfie, Solomon; Ashagre, Agenagnew; Bitew, Getachew; Tigabie, Mitkie; Reta, Melese Abate (Oxford University Press, 2025-08)
BACKGROUND : Colistin resistance in multidrug-resistant (MDR) Klebsiella pneumoniae is a growing concern in Africa, complicating treatment and public health management. Colistin is a last-resort antibiotic for Gram-negative infections, but its resistance in clinical settings presents significant challenges. This study aims to determine the pooled prevalence of colistin resistance in MDR K. pneumoniae isolates from clinical specimens in Africa. METHODS : Articles were sourced from PubMed, Scopus, ScienceDirect and Google Scholar. Studies included were those reporting colistin resistance in MDR K. pneumoniae from clinical specimens in Africa, using EUCAST and CLSI-standard drug susceptibility testing. Data were extracted into Excel and analysed using STATA 17 with a random-effects model to determine the pooled prevalence. Heterogeneity was assessed using the I2 statistic, and publication bias was checked with Egger’s test. Subgroup analyses were performed to explore heterogeneity. RESULTS : The study analysed data from 30 articles on colistin resistance in MDR K. pneumoniae. The pooled prevalence was 21.59% (95% CI: 12.12–31.06), with high heterogeneity (I2 = 99.71%). Sub-regional variation was significant (P < 0.001), with prevalence rates differing across regions: 42.34% in East Africa, 37.1% in West Africa, 17.1% in Southern Africa and 13.0% in North Africa. Country-specific rates were highest in Nigeria (39.12%), followed by Kenya (22.52%), South Africa (17.12%) and Egypt (14.0%) (P < 0.001). CONCLUSIONS : Colistin resistance in MDR K. pneumoniae is high in Africa, with notable regional differences. The study calls for strict colistin regulations, robust antimicrobial stewardship and rapid diagnostic tools for resistance detection.
Nocardia species epidemiology and susceptibility profiles from 2019 to 2022 in South Africa
Thomas, T.; Lowe, M.; Le Roux, K.; Strydom, Kathy-Anne (South african Medical Association, 2025-08)
BACKGROUND : Nocardia species cause infections in humans, from localised to disseminated disease. They constitute a public health threat owing to the lack of sufficient information about them. In South Africa (SA), the last publication on this organism was in 2010. Predominant species types and antibiotic susceptibilities may have changed over this period. OBJECTIVE : To address the knowledge gap surrounding Nocardia species and their antibiotic susceptibilities in SA. METHODS : This was a retrospective and cross-sectional study. Data were collected from the Central Data Warehouse (CDW) of the National Health Laboratory Service (NHLS) on suspected Nocardia species from 1 January 2019 to 31 December 2022. Organism speciation was performed using 16S rRNA sequencing and antibiotic susceptibility testing (AST) by the broth microdilution (BMD) method. Data analysis included patient age, sample types from which the organism was cultured, distribution in the various SA provinces, species types and species AST profiles, including a record of trimethoprim-sulfamethoxazole (TMP/SMX) non-susceptibility. RESULTS : One hundred and sixty-five positive culture results were analysed. The majority of positive cultures (28%, n=46) were from the 30 - 39-year age group. The organism was predominantly cultured from pus samples (31%, n=51). The top two provinces from which the largest numbers of isolates were submitted were Gauteng (69%, n=114) and Western Cape (18%, n=30) provinces. Two percent (n=4) of isolates were not sequenced, and 18% (n=30) of isolates lacked AST results. Twenty-nine percent (n=47) of the Nocardia species that were sequenced could not be speciated using 16S rRNA sequencing. The top two species country-wide were N. abscessus complex (25%, n=42) and N. cyriacigeorgica (18%, n=29). Approximately 90% (n=121) of all isolates tested were TMP/SMX susceptible. CONCLUSION : The predominant isolation of Nocardia species from pus samples suggests that the majority were deep-seated infections. The most common Nocardia species types and the AST profiles have changed over time. The study highlights the need for alternative methods for the speciation of this organism.
Spectrum of sexual partner types among adults screened for sexually transmitted infections in the Eastern Cape, South Africa
De Vos, Lindsey; Mdingi, Mandisa M.; Gigi, Ranjana M.S.; Gebengu, Avuyonke; Peters, Remco P.H. (Public Library of Science, 2025-05-07)
In South Africa, Chlamydia trachomatis prevalence is 14.7% in women and 6.6% in men, while Neisseria gonorrhoeae rates are 6.0% and 3.4%. Partner management, including identifying and screening for STIs, is essential for STI control efforts but challenging due to relationship dynamics, fear of disclosure and stigma. This study aims to understand how adults in the Eastern Cape report partner types when seeking STI care, enhancing partner notification strategies and reducing transmission. From February-August 2023, a cross-sectional evaluation of a Neisseria gonorrhoeae lateral flow assay was conducted among asymptomatic adults aged 18-49 years at four primary healthcare facilities in Buffalo City, Eastern Cape. Participants completed surveys classifying partners into LUSTRUM team's 8 partner types and 5 type-classifications. Data were analyzed using StataSE 17, examining associations between partner types and variables like gender, location, number of sexual partners, and STI test results. A total of 500 men and 400 women (median ages 31 and 32) were recruited. The most reported partner types were main/serious/long-term partners (41%) and girlfriend/boyfriend (29%) or LUSTRUM's 4: established (67%) and occasional partners (28%). Participants reporting main/long-term partners, steady, or boyfriend/girlfriend showed variability in partner numbers. Male adults more commonly reported casual partner types like friends with benefits (21% vs. 9%) and fuck buddy/booty call (9% vs. 3%), with significant associations for super casual/hook-up/meet/one-night stand (p = 0.02). Regional differences in partner types and a significant association between new partners and NG Xpert positivity (p = 0.01) were observed. This study confirms the diverse spectrum of sexual partner types. Findings reveal that men and women may have different relationships, and regional variations suggest context-specific approaches are needed. Identifying partner types can enhance communication and treatment strategies and address significant gaps in partner notification and STI care.
Mobile genetic elements of global Escherichia coli ST131 clades with carbapenemases
Peirano, Gisele; Matsumara, Yasufumi; Pitout, Johann D.D. (Springer, 2025-09)
Please read abstract in the article.
Genomic epidemiology of Pseudomonas aeruginosa sequence type 111
Matsumara, Yasufumi; Peirano, Gisele; Kock, Marleen M.; Pitout, Johann D.D. (Springer, 2025-02)
Please read abstract in the article.
Molecular epidemiology of global carbapenemase-producing Serratia spp. (2015-2017)
Peirano, Gisele; Matsumura, Yasufumi; Pitout, Johann D.D. (Springer, 2025-12)
Please read abstract in the article.
Value of a commercial multiplex molecular panel for the diagnosis of cholera in an outbreak setting in Hammanskraal, Tshwane, South Africa
Safiyyah, Khan; Skosana, Lebogang Busisiwe; Colloty, Jamie; Nchabeleng, Maphoshane; Ntlemo, Grace; Said, Mohamed (Elsevier, 2025-09)
Cholera is not endemic in South Africa. However, between February and July 2023, 1073 suspected cholera cases, and 198 laboratory-confirmed cases were reported nationally. This is the first report of the use of a commercial, rapid diagnostic assay in an outbreak setting. This method evaluation study was conducted at the National Health Laboratories Service (NHLS) Tshwane Microbiology laboratory in Pretoria, South Africa, during the outbreak period. Eighteen retrospective stored culture-positive Vibrio cholerae isolates and 102 prospective clinical specimens were processed on the EntericBio® Dx panel (Serosep, Limerick, Ireland) as well as the gold standard of culture. For the EntericBio® processing, stools were processed according to the manufacturer’s instructions. Real time polymerase chain reaction (PCR) was performed on the Roche LightCycler®. The diagnostic performance was compared between culture and the EntericBio® Dx assay. All discrepant results were resolved at a referral laboratory using an in-house PCR assay. The mean time to results using EntericBio® was 48 h earlier than culture results. Overall, the EntericBio® Dx panel demonstrated a sensitivity of 100 % for the detection of Vibrio species when compared to culture. Although the EntericBio® platform reported the results as Vibrio species, the pre-test probability was high for V. cholerae in an outbreak setting. Further serotyping methods have confirmed this. The quick turnaround time and excellent sensitivity of the EntericBio® platform expedites patient treatment and institution of appropriate infection control practices and has potential to rapidly control such outbreaks.
Effect of contraceptive methods on the vaginal microbiome and host immune factors
Serrano, Myrna G.; Edwards, David; Ahmed, Khatija; Bailey, Veronique C.; Beksinska, Mags; Edupuganti, Laahirie; Harryparsad, Rushil; D'Hellencourt, Florence L.; Meyer, Bahiah; Mehou-Loko, Celia; Radzey, Nina; Taku, Ongeziwe; Williamson, Anna-Lise; Smit, Jennifer; Spaine, Katherine; Zhu, Bin; Jefferson, Kimberly K.; Nanda, Kavita; Strauss III, Jerome F.; Morrison, Charles S.; Deese, Jennifer; Masson, Lindi; Buck, Gregory A.; Deese, Jennifer; Masson, Lindi; Buck, Gregory A. (Elsevier, 2025-08)
OBJECTIVE : The objective of this study was to assess alterations in vaginal microbiota and immune markers over the first 3 months following initiation of copper intrauterine device (copper IUD), levonorgestrel (LNG) implant, and intramuscular depot medroxyprogestone acetate (DMPA-IM). STUDY DESIGN : We included 162 participants from the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial, which enrolled healthy, HIV-negative women seeking contraception and randomized them to a copper IUD, LNG implant, or DMPA-IM. Microbiome and immune profiles in vaginal swab samples collected at enrollment, 1 month and 3 months were analyzed. We categorized microbiome profiles as ‘‘optimal’’, ‘‘intermediate’’, or ‘‘non-optimal’’ based on established criteria [1]. We compared microbiome and immune markers across contraceptive groups and evaluated changes to 1 and 3 months. RESULTS : Copper IUD users had a more diverse vaginal microbiome and generally increased inflammatory cytokines and antimicrobial peptides over the 3-month follow-up, compared to LNG-implant and DMPA-IM users [2]. LNG-implant users had less complex vaginal microbiomes with reduced inflammation, while DMPA-IM showed little change in either microbiome composition or inflammatory markers. Copper IUD users exhibited lower microbiome stability and a higher likelihood of transitioning to less optimal profiles. In contrast, LNG-implant users showed greater stability and a higher probability of transition to optimal microbiome and immune marker profiles. CONCLUSIONS : Contraceptive methods affect the vaginal microbiome differently. Copper IUD use may lead to less favorable profiles and increased levels of some immune markers, indicating potential adverse health effects. Conversely, LNG-implant usage promotes a more favorable microbiome and immune marker balance. IMPLICATIONS : Our findings suggest that copper IUDs are associated with decreased prevalence of Lactobacillus-dominated microbiomes, higher transition rates towards less optimal microbiome and increased inflammatory profiles, which may lead to negative implications for gynecologic and reproductive health, the LNG-implant may offer positive health benefits with increased prevalence of L. crispatus-dominated microbiomes.
Using sputum and tongue swab specimens for in-home point-of- care targeted universal testing for tuberculosis of household contacts : an acceptability and feasibility analysis
Bezuidenhout , Charl; Long, Lawrence; Nichols, Brooke; Meyer-Rath, Gesine; Fox, Matthew P.; Olifant, Sharon; Theron, Grant; Fiphaza, Kuhle; Pieruccini, Maria; Ruhwald, Morten; Penn-Nicholson, Adam; Fourie, Bernard P.; Medina-Marino, Andrew (BMJ Publishing Group, 2025-08-21)
INTRODUCTION : Effective strategies are essential for early tuberculosis (TB) detection. Reliance on passive case detection, symptom screening and collection of sputum results in delayed or undiagnosed TB, contributing to on-going TB transmission. This study assessed the acceptability of in-home targeted universal TB testing (TUTT) using GeneXpert MTB/RIF Ultra at point-of-care (POC) during household contact investigations (HCIs) and the feasibility of using sputum and tongue swab specimens. METHODS : The TB Home Study sought to evaluate the predictive value of different specimen types for use as a household-level triage test for TB. Household contacts of people with TB residing in the Buffalo City Metro Health District (Eastern Cape Province, South Africa) who received in-home POC TUTT through the TB Home Study were asked to complete a post-test acceptability survey. The survey assessed the level of comfort, confidence in the test results and perceived appropriateness of in-home POC TUTT. A feasibility framework was used to assess the feasibility of using sputum and tongue swab specimens for testing. RESULTS : Of the 325 eligible household contacts, 281/325 (86.5%) provided consent. Of those contacts, 278/281 (98.9%) provided a tongue swab, and 50/281 (17.8%) could expectorate sputum. All specimens were successfully prepared for immediate in-home testing. Of the 172 tongue swab-based tests performed, 169 (98.3%) produced a valid result, whereas 47 of 49 (95.9%) sputum-based tests had a valid result. An immediate tongue swab-based test result was available for 274/278 (98.6%) clients compared with 47/49 (95.9%) sputum-based test results. The mean in-home POC TUTT acceptability score (5=highly acceptable) was 4.2/5 (SD=0.4). CONCLUSION : In-homePOC TUTT using sputum and tongue swab specimens was highly acceptable and feasible. Tongue swabs greatly increased the testing rates owing to the high sample collection yield. Combining sputum and tongue swabs for in-home POC testing offers a promising strategy to improve TB case detection and reduce diagnostic delays.
Electro-impedimetric detection of human anti-mycolate antibody biomarkers of TB before, during, and after treatment
Baumeister, Carl Robert; Verschoor, Jan Adrianus; Ueckermann, Veronica; Molatseli, Mosa; Sesing, Thoriso; Khuboni, Nomthandazo; Fourie, Bernard P. (Taylor and Francis, 2025)
Efficient TB management requires rapid and accurate diagnosis of active pulmonary and extrapulmonary TB at the point-of-care. Blood-based antibody biomarker assays may be ideal if unaffected by HIV co-infection and antibody memory from prior TB or vaccination. AIM : This study assessed electro-impedimetric detection (EIS-MARTI) of anti-mycolate antibodies (AMAb) in TB patients before, during, and after treatment, compared to sputum culture (MGIT) as the gold standard. METHODS : A prospective pilot study enrolled 15 confirmed TB patients and 73 healthy controls at a Pretoria hospital (2016–2017). A prospective monitoring study followed 25 confirmed TB patients over 6 months of treatment at a Pretoria clinic (2019–2020) to evaluate biomarker behavior. Outcomes were analyzed using descriptive statistics, wherein diagnostic accuracy and predictive values were assessed by ROC curve analysis. RESULTS : EIS-MARTI detected 14/15 true TB-positive cases independent of HIV co-infection and 68/73 true TB-negatives in the pilot study. In the monitoring study, EIS-MARTI correlated with culture in 7/8 cases at treatment end, but not during the first 2 months. CONCLUSION : AMAbs arise independently of HIV co-infection in active TB, recede during treatment, and are rapidly detected by a hand-held EIS-MARTI device. While suitability for treatment monitoring remains uncertain, EIS-MARTI shows promise for rapid, accurate TB diagnosis and confirming cure. PLAIN LANGUAGE SUMMARY : The purpose of this work was to investigate anti-mycolate antibodies as a suitable biomarker for diagnosing tuberculosis, monitoring treatment, and screening people at risk for TB.
Empowering women's PrEP choices : qualitative insights into long-acting PrEP preferences and decision-making during pregnancy and breastfeeding in South Africa and Botswana
Chen-Charles, Jenny; De Vos, Lindsey; Vundhla, Prisca; Gebengu, Avuyonke; Rousseau, Elzette; Bekker, Linda-Gail; Peters, Remco P.H.; Mussa, Aamirah; Morroni, Chelsea; Toska, Elona; Babalola, Chibuzor M.; Klausner, Jeffrey D.; Davey, Dvora Joseph (Springer, 2026-01)
Pregnant and breastfeeding women (PBW) are at heightened risk of HIV acquisition. We aimed to explore PBW’s preferences of various long-acting PrEP modalities. In-depth interviews were conducted with PBW at three sites: Cape Town, East London (South Africa), and Gaborone (Botswana). We conducted thematic analysis, guided by the Health Belief Model, to examine participants’ HIV risk perception during pregnancy and breastfeeding, their perceived individual-level facilitators and barriers of each PrEP modality, and the support needed by participants for PrEP uptake and continuation. 40 participants were interviewed, aged 18–39 years (mean 27 years), including 13 adolescent girls and young women (AGYW; 18–24 years). Participants were either pregnant (n = 20) or breastfeeding (n = 20). Perceived HIV risk during pregnancy motivated PrEP use. Long-acting methods were preferred over daily pills for convenience and perceived reliability, with injectables most favoured due to familiarity with contraceptive injections. However, concerns about pain and side effects persisted. Monthly oral PrEP was seen as easier than daily pills but raised similar concerns about adherence. Implants were met with fear and mistrust, often rooted in negative contraceptive experiences, though some valued their long-term protection. The vaginal ring was least acceptable due to unfamiliarity and discomfort with insertion. Participants emphasised the importance of external support (e.g. reminders), privacy and discretion, and community transparency to support PrEP adherence and reduce stigma. Addressing barriers – especially concerns about the safety and effectiveness of new modalities and challenges around adherence – could help improve strategies to better assist PBW in utilising long-acting PrEP modalities.
No evidence of MMR induced trained immunity to prevent SARS COV2 : results from a multi-centre RCT
Delany-Moretlwe, Sinead; Dehbi, Hakim-Moulay; Sikazwe, Izukanji; Kyei, George; Koram, Kwadwo; Dubberke, Erik; Mwelase, Noluthando; Hague, Dominic;; Bekker, Linda-Gail; Yun, Linda; Nel, Annalene; Du Toit, Leon; Biccard, Bruce; Gill, Katherine; Chipeta, Chikumbutso; Mngadi, Kathryn T.; Lebina, Limakatso; Dassaye, Reshmi; Asari, Villeshni; Fry, Samantha H.; Turton, Edwin; Ahmed, Khatija; Kusi, Kwadwo; Adu-Amankwah, Susan; Chilengi, Roma; Chilekwa, Joyce Chinyama; Lovat, Laurence; McGuckin, Dermot; Caverly, Emilia; Politi, Mary; Swan, Ben; DeSchryver, Anne; Mckinnon, Sherry; Gupta, Ananya; Jones, Gemma; Freemantle, Nicholas; Khader, Shabaana; Rees, Helen; Netea, Mihai G.; Moonesinghe, S. Ramani; Avidan, Michael S. (Frontiers Media, 2025-09-16)
BACKGROUND : Measles-containing vaccines (MCV), by training innate immune cells, are hypothesized to prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19). METHODS : In this international, double-blind, placebo-controlled trial, we randomly assigned adults, 18 years and older, to receive MCV or saline. The primary outcome was polymerase chain reaction (PCR) confirmed symptomatic COVID-19, up to 60 days after intervention. Secondary outcomes were PCR-confirmed symptomatic COVID-19 and serologically confirmed SARS-CoV-2 infection, up to 150 days after intervention. RESULTS : Of 3411 randomised participants, the modified intention-to-treat population included 1607 in the MCV and 1545 in the saline group. The estimated risk of symptomatic COVID-19 by 60 days was 1.5% in the MCV and 1.2% in the saline group (risk difference, 0.3 percentage points, 95% CI, -0.5 to 1.1; p=0.52). At 150 days, these percentages were 4.1% (65/1585) and 4.1% (64/1544) in the MCV and saline groups, respectively (risk difference, 0.04 percentage points, 95% CI, -1.4 to 1.3; p=0.95). Based on serology results available at 0 and 150 days, 10.6% (100/945) of participants in the MCV and 10.3% (98/951) in the saline group had infection with SARS-CoV-2 over the course of the trial (risk difference, 0.3 percentage points, 95% CI, -2.6 to 3.1; p=0.84). Three patients were hospitalised with COVID-19 disease in the MCV and one in the saline group. CONCLUSIONS : Administering MCVs to stimulate trained immunity did not prevent COVID-19 or SARS-CoV2 infection. Stimulating trained immunity might not be useful for preventing respiratory illness during future pandemics. CLINICAL TRIAL REGISTRATION : https://clinicaltrials.gov/, identifier NCT04333732.
Rapidly spreading Enterobacterales with OXA-48-like carbapenemases
Peirano, Gisele; Pitout, Johann D.D. (American Society for Microbiology, 2025-02)
Enterobacterales (mostly Klebsiella pneumoniae, Escherichia coli) with OXA-48-like carbapenemases (e.g., OXA-48, -181, -232, -244) are undermining the global efficiency of carbapenem therapy. In the Middle East, North Africa, and some European countries, OXA-48-like carbapenemases are the most common types of carbapenemases among Enterobacterales. Currently, OXA-48 is endemic in the Middle East, North Africa, Spain, France, and Belgium; OXA-181 is endemic in Sub-Saharan Africa and the Indian Subcontinent, while OXA-232 has been increasing in the Indian Subcontinent. European countries (e.g., Germany, Denmark, Switzerland, France) are experiencing community outbreaks with E. coli ST38 that produce OXA-244, and these strains have been introduced into Norwegian, Polish, and Czech hospitals. The global ascendancy of OXA-48-like genes is due to the combination of carbapenemases with horizontal spread through promiscuous plasmids (e.g., IncL, IncX3, ColE2) and vertical spread with certain high-risk multidrug-resistant clones (e.g., K. pneumoniae ST14, ST15, ST147, ST307; E. coli ST38, ST410). This is a powerful “gene survival strategy” that has assisted with the survival of OXA-48-like genes in different environments including the community setting. The laboratory diagnosis is complex; therefore, bacteria with “difficult to detect” variants (e.g., OXA-244, OXA-484) are likely underreported and are spreading silently “beneath the radar” in hospital and community settings. K. pneumoniae and E. coli with OXA-48-like carbapenemases are forces to be reckoned with.
The emerging concern of IMP variants being resistant to the only IMP-type metallo-β-lactamase inhibitor, xeruborbactam
Le Terrier, Christophe; Drusin, Salvador I.; Nordmann, Patrice; Pitout, Johann D.D.; Peirano, Gisele; Vila, Alejandro J.; Moreno, Diego M.; Poirel, Laurent (American Society for Microbiology, 2025-07)
Metallo-β-lactamases (MBLs) of IMP type are not inhibited by currently commercialized β-lactamase inhibitors, including taniborbactam (TAN), which inhibits only NDM- and VIM-type enzymes. However, the development of xeruborbactam (XER), which additionally inhibits IMP enzymes, may provide effective drug combinations such as meropenem-XER (MEM-XER) against most MBL producers. Thirty-two IMP-producing clinical gram-negative isolates were tested for MEM-XER. Susceptibility testing of β-lactams with TAN or XER at 4 or 8 µg/mL was performed. Noticeably, MEM-XER remained ineffective against all IMP-producing Pseudomonas aeruginosa isolates. By contrast, supplementation with XER significantly lowered MEM MICs for several IMP-producing Enterobacterales isolates, except for isolates and recombinant E. coli strains producing IMP-6, IMP-10, IMP-14, and IMP-26. Interestingly, IMP-59 producers showed susceptibility to both TAN- and XER-based combinations, although IMP enzymes are not supposed to be inhibited by TAN. Determinations of 50% inhibitory concentration (IC50) values of XER showed values being >15-fold higher for IMP-6, IMP-10, IMP-14, and IMP-26 compared with IMP-1. Interestingly, the IC50 value of TAN for IMP-59 was found in the same range as that for NDM-1 (7 µM). Finally, structural analyses and molecular modeling simulations indicated that the Ser262Gly mutation in IMP-6 may alter the electronic properties of the active site, whereas the Phe residue in IMP-10 may exert a steric effect counteracting XER binding. Resistance to XER in IMP-6, IMP-10, IMP-14, and IMP-26 variants, conferring resistance to MEM-XER, might be considered a serious concern since MEM-XER will be supposed to be a salvage therapy for MBL-, and especially IMP-producing Enterobacterales infections.
Static vs. cidal : it's not complex; it's simply incorrect
Spellberg, Brad; Wald-Dickler, Noah; Holtom, Paul; Meyer-Sautter, Pascal; Camp, Austin; Diaz, Alejandro Diaz; Buhamad, Ranya; Vazquez, Ali Sebastian Meza; Aguirre-Garcia, Gloria Mayela; Stanton, Matthew; Butler-Wu, Susan M.; Chiu, Isabelle; Ergenc, Zeynep; Bhoojhawon, Guru; Murri, Rita; Maraolo, Alberto Enrico; Cabanilla, Gabriela; Riccardi, Niccolo; Tshisevhe, Vhudzani; Behenna, Curtis; Williams, Karen S.; Kufel, Wesley D.; Wojciaczyk, Natalia; Pimentel, Bernardo Vidal; Muyidi, Ahmed; Costa, Rodrigo P.L.; Motta, Fabrizio; Bortolussi-Courval, Emilie; Lee, Todd C.; Mcdonald, Emily; Ghanem, Bassam; Nelson, Zachary (American Society for Microbiology, 2025-08)
No abstract available.

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