Prevalence and antimicrobial resistance of Salmonella in conventional and no antibiotics ever broiler farms in the United States

ABSTRACT Although changing patterns in antimicrobial resistance inStreptococcus pneumoniae have prompted several surveillance initiatives in recent years, the frequency with which these studies are needed has not been addressed. To approach this issue, the extent to which resistance patterns change over a 1-year period was examined. In this study we analyzed S. pneumoniaeantimicrobial susceptibility results produced in our laboratory with isolates obtained over 2 consecutive years (1997–1998 and 1998–1999) from the same 96 institutions distributed throughout the United States. Comparison of results revealed increases in resistant percentages for all antimicrobial agents studied except vancomycin. For four of the agents tested (penicillin, cefuroxime, trimethoprim-sulfamethoxazole, and levofloxacin), the increases were statistically significant (P < 0.05). Resistance to the fluoroquinolone remained low in both years (0.1 and 0.6%, respectively); in contrast, resistance to macrolides was consistently greater than 20%, and resistance to trimethoprim-sulfamethoxazole increased from 13.3 to 27.3%. Multidrug resistance, concurrent resistance to three or more antimicrobials of different chemical classes, also increased significantly between years, from 5.9 to 11%. The most prevalent phenotype was resistance to penicillin, azithromycin (representative macrolide), and trimethoprim-sulfamethoxazole. Multidrug-resistant phenotypes that included fluoroquinolone resistance were uncommon; however, two phenotypes that included fluoroquinolone resistance not found in 1997–1998 were encountered in 1998–1999. This longitudinal surveillance study of resistance inS. pneumoniae revealed that significant changes do occur in just a single year and supports the need for surveillance at least on an annual basis, if not continuously.

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Molecular Analysis ofEscherichia colifrom Retail Meats (2002–2004) from the United States National Antimicrobial Resistance Monitoring System

Clinical Infectious Diseases ◽

10.1086/599830 ◽

2009 ◽

Vol 49 (2) ◽

pp. 195-201 ◽

Cited By ~ 35

Author(s):

James R. Johnson ◽

James S. McCabe ◽

David G. White ◽

Brian Johnston ◽

Michael A. Kuskowski ◽

...

Keyword(s):

United States ◽

Antimicrobial Resistance ◽

Monitoring System ◽

Molecular Analysis ◽

The United States ◽

Resistance Monitoring ◽

Retail Meats

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Emergence of high rates of antimicrobial resistance among viridans group streptococci in the United States.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.40.4.891 ◽

1996 ◽

Vol 40 (4) ◽

pp. 891-894 ◽

Cited By ~ 184

Author(s):

G V Doern ◽

M J Ferraro ◽

A B Brueggemann ◽

K L Ruoff

Keyword(s):

United States ◽

Antimicrobial Resistance ◽

Blood Culture ◽

Rank Order ◽

The United States ◽

Medical Centers ◽

Streptococcus Milleri ◽

Intermediate Resistance ◽

High Level ◽

Viridans Group Streptococci

Three hundred fifty-two blood culture isolates of viridans group streptococci obtained from 43 U.S. medical centers during 1993 and 1994 were characterized. Included were 48 isolates of "Streptococcus milleri," 219 S. mitis isolates, 29 S. salivarius isolates, and 56 S. sanguis isolates. High-level penicillin resistance (MIC, > or = 4.0 micrograms/ml) was noted among 13.4% of the strains; for 42.9% of the strains, penicillin MICs were 0.25 to 2.0 micrograms/ml (i.e., intermediate resistance). In general, amoxicillin was slightly more active than penicillin. The rank order of activity for five cephalosporins versus viridans group streptococci was cefpodoxime = ceftriaxone > cefprozil = cefuroxime > cephalexin. The percentages of isolates resistant (MIC, > or = 2 micrograms/ml) to these agents were 15, 17, 18, 20, and 96, respectively. The rates of resistance to erythromycin, tetracycline, and trimethoprim-sulfamethoxazole were 12 to 38%. Resistance to either chloramphenicol or ofloxacin was uncommon (i.e., < 1%). In general, among the four species, S. mitis was the most resistant and "S. milleri" was the most susceptible.

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Where have all the susceptible gonococci gone? A historical review of changes in MIC distribution over the past 75 years

10.21203/rs.2.13785/v2 ◽

2019 ◽

Author(s):

Chris Kenyon ◽

Jolein Laumen ◽

Dorien Van Den Bossche ◽

Christophe Van Dijck

Keyword(s):

United States ◽

South Africa ◽

Antimicrobial Resistance ◽

Historical Analysis ◽

Historical Review ◽

The United States ◽

Antimicrobial Consumption ◽

The Past ◽

The United Kingdom ◽

Loss Of Susceptibility

Abstract Background Does the emergence of antimicrobial resistance in Neisseria gonorrhoeae include the erasure of highly susceptible strains or does it merely involve a stretching of the MIC distribution? If it was the former this would be important to know as it would increase the probability that the loss of susceptibility is irreversible.Methods We conducted a historical analysis based on a literature review of changes of N. gonorrhoeae MIC distribution over the past 75 years for 3 antimicrobials (benzylpenicillin, ceftriaxone and azithromycin) in five countries (Denmark, Japan, South Africa, the United Kingdom and the United States).Results Changes in MIC distribution were most marked for benzylpenicillin and showed evidence of a right shifting of MIC distribution that was associated with a reduction/elimination of susceptible strains in all countries. In the case of ceftriaxone and azithromycin, where only more recent data was available, right shifting was also found in all countries but the extent of right shifting varied and the evidence for the elimination of susceptible strains was more mixed.Conclusions The finding of right shifting of MIC distribution combined with reduction/elimination of susceptible strains is concerning since it suggests that this shifting may not be reversible. Since excess antimicrobial consumption is likely to be responsible for this right shifting, this insight provides additional impetus to promote antimicrobial stewardship.

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Association between intensity of STI screening and development of antimicrobial resistance in N. gonorrhoeae in 12 cities in the USA: An ecological study

F1000Research ◽

10.12688/f1000research.15569.3 ◽

2018 ◽

Vol 7 ◽

pp. 1237

Author(s):

Chris R. Kenyon

Keyword(s):

United States ◽

Antimicrobial Resistance ◽

Ecological Study ◽

Geometric Mean ◽

The United States ◽

Transmitted Infection ◽

Sexually Transmitted ◽

Antimicrobial Sensitivity ◽

The Usa ◽

Sex With Men

In this study, we assessed if there was a city-level association between sexually transmitted infection (STI) screening intensity in men who have sex with men and antimicrobial sensitivity in Neisseria gonorrhoeae in the United States, 2007 to 2013. We found positive associations between STI screening intensity and increases in minimum inhibitory concentrations for cefixime and azithromycin, but not ceftriaxone when using change in city geometric mean N. gonorrhoeae MIC between 2005 and 2013.

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Trends in antimicrobial resistance among Bacteroides species and Parabacteroides species in the United States from 2010–2012 with comparison to 2008–2009

Anaerobe ◽

10.1016/j.anaerobe.2016.11.003 ◽

2017 ◽

Vol 43 ◽

pp. 21-26 ◽

Cited By ~ 27

Author(s):

D.R. Snydman ◽

N.V. Jacobus ◽

L.A. McDermott ◽

E.J.C. Goldstein ◽

L. Harrell ◽

...

Keyword(s):

United States ◽

Antimicrobial Resistance ◽

The United States ◽

Bacteroides Species

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Longitudinal Assessment of Antipneumococcal Susceptibility in the United States

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.8.2651-2655.2002 ◽

2002 ◽

Vol 46 (8) ◽

pp. 2651-2655 ◽

Cited By ~ 21

Author(s):

Mark E. Jones ◽

James A. Karlowsky ◽

Renée Blosser-Middleton ◽

Ian A. Critchley ◽

Elena Karginova ◽

...

Keyword(s):

United States ◽

Multidrug Resistance ◽

Antimicrobial Resistance ◽

The United States ◽

Longitudinal Assessment ◽

Amoxicillin Clavulanate ◽

Resistance To Penicillin

ABSTRACT The prevalence of antimicrobial resistance among 4,940 U.S. pneumococcal isolates collected during 1999 was as follows: penicillin, 16.2%; amoxicillin-clavulanate, 12.2%; cefuroxime, 28.1%; ceftriaxone, 3.6%; trimethoprim-sulfamethoxazole, 30.3%; azithromycin, 21.4%; levofloxacin, 0.6%; and moxifloxacin, 0.1%. Compared to the previous 1997-1998 study (Jones et al., Antimicrob. Agents Chemother. 44:2645-2652, 2000), increases were noted for resistance to penicillin (3.7%; P < 0.001), amoxicillin-clavulanate (3.9%; P < 0.001), cefuroxime (5.7%; P < 0.001), azithromycin (2.4%; P = 0.014), trimethoprim-sulfamethoxazole (15.4%; P < 0.001), and levofloxacin (0.3%; P = 0.017). Resistance to ceftriaxone (0.1%; P = 0.809) and moxifloxacin (0.03%; P = 0.570) decreased. Concurrently, multidrug resistance increased (P < 0.001) from 6.3% to 11.3%.

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Population-Based Surveillance of Neisseria meningitidis Antimicrobial Resistance in the United States

Open Forum Infectious Diseases ◽

10.1093/ofid/ofv117 ◽

2015 ◽

Vol 2 (3) ◽

Cited By ~ 29

Author(s):

Brian H. Harcourt ◽

Raydel D. Anderson ◽

Henry M. Wu ◽

Amanda C. Cohn ◽

Jessica R. MacNeil ◽

...

Keyword(s):

United States ◽

Antimicrobial Resistance ◽

Neisseria Meningitidis ◽

Susceptibility Testing ◽

The United States ◽

Population Based ◽

Antimicrobial Treatment ◽

Penicillin G ◽

Gyra Gene ◽

Active Population

Abstract Background. Antimicrobial treatment and chemoprophylaxis of patients and their close contacts is critical to reduce the morbidity and mortality and prevent secondary cases of meningococcal disease. Through the 1990's, the prevalence of antimicrobial resistance to commonly used antimicrobials among Neisseria meningitidis was low in the United States. Susceptibility testing was performed to ascertain whether the proportions of isolates with reduced susceptibility to antimicrobials commonly used for N meningitidis have increased since 2004 in the United States. Methods. Antimicrobial susceptibility testing was performed by broth microdilution on 466 isolates of N meningitidis collected in 2004, 2008, 2010, and 2011 from an active, population-based surveillance system for susceptibility to ceftriaxone, ciprofloxacin, penicillin G, rifampin, and azithromycin. The molecular mechanism of reduced susceptibility was investigated for isolates with intermediate or resistant phenotypes. Results. All isolates were susceptible to ceftriaxone and azithromycin, 10.3% were penicillin G intermediate (range, 8% in 2008–16.7% in 2010), and <1% were ciprofloxacin, rifampin, or penicillin G resistant. Of the penicillin G intermediate or resistant isolates, 63% contained mutations in the penA gene associated with reduced susceptibility to penicillin G. All ciprofloxacin-resistant isolates contained mutations in the gyrA gene associated with reduced susceptibility. Conclusions. Resistance of N meningitidis to antimicrobials used for empirical treatment of meningitis in the United States has not been detected, and resistance to penicillin G and chemoprophylaxis agents remains uncommon. Therapeutic agent recommendations remain valid. Although periodic surveillance is warranted to monitor trends in susceptibility, routine clinical testing may be of little use.

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