Interactions among Strategies Associated with Bacterial Infection: Pathogenicity, Epidemicity, and Antibiotic Resistance

Abstract

SUMMARY Infections have been the major cause of disease throughout the history of human populations. With the introduction of antibiotics, it was thought that this problem should disappear. However, bacteria have been able to evolve to become antibiotic resistant. Nowadays, a proficient pathogen must be virulent, epidemic, and resistant to antibiotics. Analysis of the interplay among these features of bacterial populations is needed to predict the future of infectious diseases. In this regard, we have reviewed the genetic linkage of antibiotic resistance and bacterial virulence in the same genetic determinants as well as the cross talk between antibiotic resistance and virulence regulatory circuits with the aim of understanding the effect of acquisition of resistance on bacterial virulence. We also discuss the possibility that antibiotic resistance and bacterial virulence might prevail as linked phenotypes in the future. The novel situation brought about by the worldwide use of antibiotics is undoubtedly changing bacterial populations. These changes might alter the properties of not only bacterial pathogens, but also the normal host microbiota. The evolutionary consequences of the release of antibiotics into the environment are largely unknown, but most probably restoration of the microbiota from the preantibiotic era is beyond our current abilities.

Antimicrobial resistance and virulence genes of non-typhoidal Salmonella isolates in The Gambia and Senegal

“…The simultaneous presence in the same bacterial cell of a resident virulence plasmid and resistance gene has been frequently reported in Salmonella [12]. It has been reported that resistance plasmids carry genes encoding virulence factors [23]. Also, antibiotic resistance and virulence genes can be linked in the same replicon, or eventually a single determinant can be involved in both virulence and resistance [23].…”

Antimicrobial resistance, presence of integrons and biofilm formation ofSalmonellaPullorum isolates from eastern China (1962–2010)

“…The increasing appearance of multidrug-resistant Salmonella has become a worldwide concern. The link between the use of antimicrobials in food animals and the emergence of antimicrobial resistance of human pathogenic bacteria is well documented (Martínez & Baquero, 2002;Ahmed et al, 2009;Araque, 2009). Integrons are capable of capturing and mobilizing antimicrobial resistance bacterial genes.…”

Antibiotics as intermicrobial signaling agents instead of weapons

“…Learning the response of P. aeruginosa to subinhibitory concentrations of antibiotics is thus a relevant task to understanding the biological responses of this bacterium in patients under treatment (6). To that goal, we have developed a P. aeruginosa subgenomic DNA microarray containing 555 genes selected as relevant for the development of chronic colonization and infection, antibiotic resistance, transcriptional regulation, and stress response.…”