A global view of antibiotic resistance

Martínez, José Luis; Fajardo, Alicia; Garmendia, Leonor; Hernandez, Alvaro G.; Linares, Juan F.; Martínez-Solano, Laura; Sánchez, María Blanca

doi:10.1111/j.1574-6976.2008.00142.x

Cited by 296 publications

(243 citation statements)

References 263 publications

(361 reference statements)

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“…Furthermore, resistance genes may be transferred horizontally to environmental microorganisms, those of the microbiota (MARTINEZ et al, 2009;WITTE, 2000), and even strictly human pathogens, limiting therapeutic options.…”

Section: Discussionmentioning

confidence: 99%

In vitro antimicrobial susceptibility and genetic resistance determinants of Streptococcus agalactiae isolated from mastitic cows in Brazilian dairy herds

Silva

Castro

Gonçalves

et al. 2017

SCA

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Streptococcus agalactiae is one of the main causative agents of bovine mastitis and is associated with several economic losses for producers. Few studies have evaluated antimicrobial susceptibility and the prevalence of genetic resistance determinants among isolates of this bacterium from Brazilian dairy cattle. This work aimed to evaluate the frequency of the antimicrobial resistance genes ermA, ermB, mefA, tetO, tetM, aphA3, and aad-6, and in vitro susceptibility to the antimicrobials amikacin, erythromycin, clindamycin, tetracycline, gentamicin, penicillin, ceftiofur, and cefalotin, and the associations between resistance genotypes and phenotypes among 118 S. agalactiae isolates obtained from mastitic cows in Brazilian dairy herds. Of the resistance genes examined, ermB was found in 19 isolates (16.1%), tetO in 23 (19.5%), and tetM in 24 (20.3%). The genes ermA, mefA, aphA3, and aad-6 were not identified. There was an association between the presence of genes ermB, tetM, and tetO and phenotypic resistance to erythromycin, clindamycin, and tetracycline. Rates of resistance to the tested antibiotics varied, as follows: erythromycin (19.5%), tetracycline (35.6%), gentamicin (9.3%), clindamycin (20.3%), penicillin (3.4%), and amikacin (38.1%); conversely, all isolates were susceptible to ceftiofur and cefalotin. Antimicrobial resistance testing facilitates the treatment decision process, allowing the most judicious choice of antibiotics. Moreover, it enables regional and temporal monitoring of the resistance dynamics of this pathogen of high importance to human and animal health. Key words: Antimicrobial resistance genes. Bovine diseases. Bovine mastitis. GBS, MIC. ResumoStreptococcus agalactiae é um dos principais agentes causadores de mastite em bovinos e de consequentes perdas econômicas aos produtores. Poucos estudos que avaliaram a susceptibilidade a antimicrobianos e a presença de determinantes genéticos de resistência para este agente em bovinos leiteiros do Brasil. Este trabalho teve por objetivo avaliar a frequência dos genes de resistência a antimicrobianos ermA, ermB, mefA, tetO, tetM, aphA3, aad-6, bem como a susceptibilidade in vitro aos antimicrobianos amicacina, eritromicina, clindamicina, tetraciclina, gentamicina, penicilina, ceftiofur e cefalotina, e as associações entre genótipos e fenótipos de resistência em 118 isolados de S. agalactiae provenientes de casos de mastite em rebanhos bovinos brasileiros. Dentre os genes de resistência pesquisados, ermB foi encontrado em 19 isolados (16,1%), tetO em 23 (19,5%) e tetM em 24 (20,3%). Os genes ermA, mefA, apha3 e aad6 não foram detectados. Verificou-se associação entre a presença dos genes ermB, tetM e tetO e os fenótipos de resistência à eritromicina, clindamicina e tetraciclina. Foram encontrados diferentes índices de resistência aos antibióticos testados: Eritromicina (19,5%), tetraciclina (35,6%), gentamicina (9,3%), clindamicina (20,3%), penicilina (3,4%) e amicacina (38,1%). Todos os isolados foram susceptíveis ceftiofur e cefalotina. ...

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Section: Discussionmentioning

confidence: 99%

In vitro antimicrobial susceptibility and genetic resistance determinants of Streptococcus agalactiae isolated from mastitic cows in Brazilian dairy herds

Silva

Castro

Gonçalves

et al. 2017

SCA

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“…Despite the clear benefits of antibiotics to agriculture, liberal antibiotic use combined with rapid and widespread emergence of both animal and human pathogens resistant to multiple antibiotics has led some to question the prudence of current antibiotic use (4,5). Studies of environmental and intestinal microbial communities reveal enormous diversity of antibiotic resistance genes (6)(7)(8). The addition of antibiotics to feed introduces a selective pressure that may lead to lasting changes in livestock commensal microorganisms.…”

mentioning

confidence: 99%

In-feed antibiotic effects on the swine intestinal microbiome

Looft

Johnson

Allen³

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

913

661

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Antibiotics have been administered to agricultural animals for disease treatment, disease prevention, and growth promotion for over 50 y. The impact of such antibiotic use on the treatment of human diseases is hotly debated. We raised pigs in a highly controlled environment, with one portion of the littermates receiving a diet containing performance-enhancing antibiotics [chlortetracycline, sulfamethazine, and penicillin (known as ASP250)] and the other portion receiving the same diet but without the antibiotics. We used phylogenetic, metagenomic, and quantitative PCR-based approaches to address the impact of antibiotics on the swine gut microbiota. Bacterial phylotypes shifted after 14 d of antibiotic treatment, with the medicated pigs showing an increase in Proteobacteria (1-11%) compared with nonmedicated pigs at the same time point. This shift was driven by an increase in Escherichia coli populations. Analysis of the metagenomes showed that microbial functional genes relating to energy production and conversion were increased in the antibiotic-fed pigs. The results also indicate that antibiotic resistance genes increased in abundance and diversity in the medicated swine microbiome despite a high background of resistance genes in nonmedicated swine. Some enriched genes, such as aminoglycoside O-phosphotransferases, confer resistance to antibiotics that were not administered in this study, demonstrating the potential for indirect selection of resistance to classes of antibiotics not fed. The collateral effects of feeding subtherapeutic doses of antibiotics to agricultural animals are apparent and must be considered in cost-benefit analyses.intestinal microbiota | microbiome shifts | swine bacteria | BioTrove microarray | metagenomics

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“…Resistance determinants to these antibiotics were originally selected in their hosts for metabolic purposes or signal trafficking. Other antibiotic-resistance genes have been obtained by virulent bacteria through horizontal gene transfer (Martinez et al, 2009a). For example, S. aureus mecA gene is located on a mobile genetic element, the staphylococcal cassette chromosome mec (SCCmec) (Tsubakshita et al, 2010), horizontally acquired from other staphylococcal species S. sciuri (Couto et al, 1996) and S. fleurettii (Katayama et al, 2000).…”

Section: Wwwintechopencommentioning

confidence: 99%

“…Under physiological conditions, efflux pumps are involved in housekeeping activities like detoxification of intracellular metabolites, cell homeostasis, intracellular signal trafficking and bacterial virulence in animal and plant hosts. However, in the presence of high concentration of antibiotics and other environmental factors, they can shift their functional roles (Martinez et al, 2009a). …”

Section: Wwwintechopencommentioning

confidence: 99%