resistance
Epidemiology and SurveillanceContinued Low Efficacy of Artemether-Lumefantrine in Angola in 2019Biennial therapeutic efficacy monitoring is a crucial activity for ensuring the efficacy of currently used artemisinin-based combination therapy in Angola. Children with acute uncomplicated Plasmodium falciparum infection in sentinel sites in the Benguela, Zaire, and Lunda Sul Provinces were treated with artemether-lumefantrine (AL) or artesunate-amodiaquine (ASAQ)...
Editor's Pick Mechanisms of ResistanceMutations in fbiD (Rv2983) as a Novel Determinant of Resistance to Pretomanid and Delamanid in Mycobacterium tuberculosisThe nitroimidazole prodrugs delamanid and pretomanid comprise one of only two new antimicrobial classes approved to treat tuberculosis (TB) in 50 years. Prior in vitro studies suggest a relatively low barrier to nitroimidazole resistance in Mycobacterium tuberculosis, but clinical evidence is limited to date. We selected pretomanid-resistant...
SusceptibilityIn Vitro Activity Analysis of a New Polymyxin, SPR741, Tested in Combination with Antimicrobial Agents against a Challenge Set of Enterobacteriaceae, Including Molecularly Characterized StrainsThe activities of azithromycin, fusidic acid, vancomycin, doxycycline, and minocycline were evaluated alone and in combination with SPR741. A total of 202 Escherichia coli and 221 Klebsiella pneumoniae isolates were selected, and they included a genome-sequenced subset (n = 267), which was...
Antiviral AgentsMutations Identified in the Hepatitis C Virus (HCV) Polymerase of Patients with Chronic HCV Treated with Ribavirin Cause Resistance and Affect Viral Replication FidelityRibavirin has been used for 25 years to treat patients with chronic hepatitis C virus (HCV) infection; however, its antiviral mechanism of action remains unclear. Here, we studied virus evolution in a subset of samples from a randomized 24-week trial of ribavirin monotherapy versus placebo in chronic HCV patients, as well as the viral resistance mechanisms of the observed ribavirin-associated mutations in cell culture. Thus, we...
Mechanisms of ResistanceEffect of Exposure to Chlorhexidine Residues at “During Use” Concentrations on Antimicrobial Susceptibility Profile, Efflux, Conjugative Plasmid Transfer, and Metabolism of Escherichia coliThere is no standardized protocol to predict the concentration levels of microbicides that are left on surfaces as a result of the use of these products, and there is no standardized method to predict the potential risk that such levels pose to emerging antibacterial resistance. The ability to distinguish between selection and adaption processes for antimicrobial resistance in bacteria and the impact of different concentrations of...
SusceptibilityIn Vitro Activity of Manogepix against Multidrug-Resistant and Panresistant Candida auris from the New York OutbreakAn ongoing Candida auris outbreak in the New York metropolitan area is the largest recorded to date in North America. Laboratory surveillance revealed NY C. auris isolates are resistant to fluconazole, with variable resistance to other currently used broad-spectrum antifungal drugs, and that several...
SusceptibilityNatural Polymorphisms in Mycobacterium tuberculosis Conferring Resistance to Delamanid in Drug-Naive PatientsMutations in the genes of the F420 signaling pathway of Mycobacterium tuberculosis complex, including dnn, fgd1, fbiA, fbiB, fbiC, and fbiD, can lead to delamanid resistance. We searched for such mutations among 129 M. tuberculosis...
Mechanisms of ResistanceCharacterization of Large Deletion Mutants of Mycobacterium tuberculosis Selected for Isoniazid ResistanceLarge genomic deletions (LGDs) (6 to 63 kbp) were observed in isoniazid-resistant Mycobacterium tuberculosis mutants derived from four M. tuberculosis strains. These LGDs had no growth defect in vitro but could be defective in intracellular growth and showed various sensitivities toward...
Antiviral AgentsAssessment of Drug Resistance during Phase 2b Clinical Trials of Presatovir in Adults Naturally Infected with Respiratory Syncytial VirusThis study summarizes drug resistance analyses in 4 recent phase 2b trials of the respiratory syncytial virus (RSV) fusion inhibitor presatovir in naturally infected adults. Adult hematopoietic cell transplant (HCT) recipients, lung transplant recipients, or hospitalized patients with naturally acquired, laboratory-confirmed RSV infection were enrolled in 4 randomized, double-blind, placebo-controlled studies with study-specific...
Mechanisms of ResistanceAntileishmanial Aminopyrazoles: Studies into Mechanisms and Stability of Experimental Drug ResistanceCurrent antileishmanial treatment is hampered by limitations, such as drug toxicity and the risk of treatment failure, which may be related to parasitic drug resistance. Given the urgent need for novel drugs, the Drugs for Neglected Diseases initiative (DNDi) has undertaken a drug discovery program, which has resulted in the identification of aminopyrazoles, a highly promising antileishmanial chemical series. Multiple...