{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:21:13Z","timestamp":1760059273926,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,5,30]],"date-time":"2025-05-30T00:00:00Z","timestamp":1748563200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Swedish International Development Agency under the Joint Programming Initiative on Antimicrobial Resistance, through the African Population Health Research Centre (APHRC)","award":["274.846","2010\/859"],"award-info":[{"award-number":["274.846","2010\/859"]}]},{"name":"Helse Nord Award","award":["274.846","2010\/859"],"award-info":[{"award-number":["274.846","2010\/859"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background\/Objectives: Wastewater treatment plants (WWTPs) serve as a sink for both antimicrobial residues and bacteria carrying resistant genes, which are later disseminated into the environment, facilitating the spread of antimicrobial resistance. This study investigated the presence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (Ec), Klebsiella pneumoniae (Kp), and Enterobacter cloacae (Enc) in effluent from WWTP in Blantyre, Malawi, to generate evidence and provide baseline information for interventions. Methods: Selective chromogenic agar was used to identify ESBL-producing bacteria. Results: A total of 288 samples were collected between April 2023 and March 2024, and 97.6% (281\/288) yielded one or more presumptive ESBL isolates. Bacterial growth was confirmed as 48.9% Ec (255\/522), 33.0% Kp (172\/522), and 10.0% Enc (52\/522). Antibiotic susceptibility testing showed the highest resistance to ceftriaxone (Ec, 100.0%; Kp, 98.3%; Enc, 100.0%) and the lowest resistance to meropenem (Ec, 6.3%, Kp, 1.2%; Enc, 3.8%) among the antibiotics that were tested. Multiple antibiotic resistance phenotypes were observed in 73.1% of the isolates, with the most prevalent phenotype being amoxicillin + clavulanate\/cotrimoxazole\/doxycycline\/ciprofloxacin\/gentamicin\/azithromycin\/ceftriaxone (55, 15.7%). Conclusions: The study demonstrated ongoing environmental contamination with antibiotic-resistant bacteria from sewage effluent. Therefore, the functionality of WWTPs should be improved to minimize the release of these organisms into the environment.<\/jats:p>","DOI":"10.3390\/antibiotics14060562","type":"journal-article","created":{"date-parts":[[2025,6,2]],"date-time":"2025-06-02T11:40:32Z","timestamp":1748864432000},"page":"562","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Prevalence of Extended-Spectrum \u03b2-Lactamase-Producing Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae in Wastewater Effluent in Blantyre, Malawi"],"prefix":"10.3390","volume":"14","author":[{"given":"Edna","family":"Ibrahim","sequence":"first","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"},{"name":"School of Science and Technology, Malawi University of Business and Applied Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charity","family":"Mkwanda","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9289-3704","authenticated-orcid":false,"given":"Edward","family":"Masoambeta","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Luigia","family":"Scudeller","sequence":"additional","affiliation":[{"name":"Scientific Direction, Fondazione IRCCS Policlinico San Matteo, Viale Camillo Golgi 19, 27100 Pavia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1259-4876","authenticated-orcid":false,"given":"Tomislav","family":"Kostyanev","sequence":"additional","affiliation":[{"name":"Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4473-296X","authenticated-orcid":false,"given":"Hussein H.","family":"Twabi","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"},{"name":"Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yohane K.","family":"Diness","sequence":"additional","affiliation":[{"name":"Malawi Liverpool Wellcome Program, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jobiba","family":"Chinkhumba","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Janelisa","family":"Musaya","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rajhab S.","family":"Mkakosya","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Surbhi","family":"Malhotra-Kumar","sequence":"additional","affiliation":[{"name":"Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chantal M.","family":"Morel","sequence":"additional","affiliation":[{"name":"Institute for Public Health and Hygiene, University Hospital Bonn, Venusberg-Campus 1, 53127 Bonn, Germany"},{"name":"KPM Center for Public Management, University of Bern, Schanzeneckstrasse 1, 3012 Bern, Germany"},{"name":"Multidisciplinary Center for Infectious Diseases, University of Bern, Hallerstrasse 6, 3012 Bern, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3329-5875","authenticated-orcid":false,"given":"Save","family":"Kumwenda","sequence":"additional","affiliation":[{"name":"School of Science and Technology, Malawi University of Business and Applied Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2304-886X","authenticated-orcid":false,"given":"Chisomo L.","family":"Msefula","sequence":"additional","affiliation":[{"name":"Pathology Department, Kamuzu University of Health Sciences, Blantyre 312200, Malawi"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Singer, A.C., Shaw, H., Rhodes, V., Hart, A., and Balcazar, J.L. 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