The Role of Antimicrobial Use in the Epidemiology of Resistant Pneumococci: A 10-Year Follow Up

Abstract

The relative effects of risk factors on the prevalence of resistant pneumococcal clones are hard to determine. Our aim was to evaluate the effect of risk factors on the prevalence of resistant pneumococci in Iceland in 2003 and compare these data with results of identical studies performed in 1993 and 1998. A randomized sample of 1,107 children was chosen from all 2,532 children 1 to 6 years old living in four communities. Pneumococci were carried by 64% of the 824 children enrolled and 9.5% were penicillin nonsusceptible (PNSP), as opposed to 8.1% (1998) and 8.5% (1993), and multiresistant strains of serotype 6B were 2.5% compared to 7.5% and 7.7% (p < 0.001). Antimicrobial use had declined in 10 years from 1.5 to 1.0 courses/child per year. The only significant risk factor for carriage of PNSP and erythromycin-resistant pneumococci was antimicrobial consumption. The multiresistant type 6B strains disappeared from the areas with the lowest antimicrobial use but maintained unchanged prevalence in the area with the highest use. The number of erythromycin- resistant, penicillin-susceptible strains of all pneumococci (37/475, 7.8%) increased significantly from the previous studies (7/353, 2.0%, 1998, and 2/390, 0.5%, 1993). This observation is associated with increased use of macrolides, especially azithromycin, in one of the study areas. Spread of novel resistant clones appears to be the main reason for rapid and significant changes in pneumococcal resistance rates. The choice of antimicrobial class appears to influence the selective environment favoring particular resistant clones.

Antibiotic use and population ecology: How you can reduce your "resistance footprint"

“…Ecological studies, which measure both resistance and use at the population level rather than the individual or institutional level, demonstrate that the spatial and temporal distribution of resistance is strongly associated with the rate of use of specific classes of antibiotics in human populations. [12][13][14][15][16][17][18][19][20] These studies show a clear association between the use of penicillins, macrolides and fluoroquinolones and drug resistance in common human pathogens like Streptococcus pneumoniae and between the use of fluoroquinolones and resistance in Escherichia coli.…”

“…Several studies indicate that azithromycin is far more likely to select for macrolide resistance than drugs of the same class with shorter half-lives. [18][19][20][21] Finally, there is also strong ecological evidence that deliberate efforts to control antimicrobial use can have beneficial effects on the trajectory of resistance. 12,18,25 It appears that populations that use antibiotics prudently are benefiting.…”

The Role of Poverty in Antimicrobial Resistance

“…25 Investigators in Iceland showed the disappearance of a multidrugresistant strain of Pneumoccoci after 10 years in areas of lowest antimicrobial use and unchanged prevalence in areas of highest antimicrobial use. 26 Restricting over-the-counter dispensation of antimicrobials without a prescription will eliminate a large source of antibiotic usage; studies indicate that more than 50% of antibiotics dispensed in developing countries are done without a prescription. 12,13,27 Implementation would require governmental intervention to develop laws and regulations and to provide the means to enforce and monitor them.…”

Antibiotic prescribing and expenditures in outpatient adults in Greece, 2010 to 2013: evidence from real-world practice

“…There is evidence that a number of antibiotic prescriptions are dispensed for viral infections, for which antibiotics provide no benefit [2]. Such prescriptions indicate an overuse of antibiotics, a common and alarming problem for many countries, potentially resulting in redundant drug spending, increased risks of adverse effects and development of antimicrobial resistance [3][4][5]. The latter is a rapidly growing global health problem [6][7][8].…”