Antibiotic usage

Antibiotics were used in folk medicine at least as early as 2500 years ago when the Chinese reported the medicinally beneficial effects of moldy bean curd. Evidence for some type of tetracycline antibiotic usage by the Sudanese-Nubian civilization (350 AD) was reported in 1980 (6). Fluorescent areas in human bones from this eta were observed that were identical in location and characteristics to modern bone from patients treated with tetracyclines. Identification of tetracycline in the ancient bones was further substantiated by fluorescence spectmm measurements and microbiological inhibition studies (7). 

Veterinary Applications. Another use for antibiotics is for veterinary appHcations and for animal feed supplements to promote growth in Hvestock (see Feeds and feed additives). Feed antibiotics used in the United States far surpass all other agricultural appHcations in terms of kilogram quantities used and approach quantities used in human medicines (25). In 1980 the USA feed antibiotic usage was estimated to be between five and six million kg. The U.S. Council of Agricultural Science and Technology estimates that feed additives save the U.S. consumer approximately 3500 million per year in meat prices, and antibiotic use accounts for most of this. 

Three broad groupings, of the antibiotic substances presently used in animal production, include (a) broad-spectrum antibiotics, including penicillins and tetracyclines, which are effective against a wide variety of pathogenic and non-pathogenic bacteria (b) several narrow-spectrum antibiotics that are not used in human medicine and. (c) the ionophore antibiotics, monensin. lasalocid and salinomycin Monensin and lasalocid are used as rumen fermentation regulators in beef cattle, and the three ionophores are used as coccidiostats in poultry production. The ionophores. which are not used in human medicine, were first introduced in the 1970 s and account for most of the increase in antibiotic usage in animal production since the 1960 s. 

These two herds have provided information on development, persistency and transfer of antibacterial resistance and. furthermore, they have provided information regarding the impact the previously proposed restrictions (Fed. Reg. 42 43770 and 42 52645. 1977) of antibiotic usage would have on antibiotic resistant bacteria of animal origin as a health hazard to humans. 

It may conceivably be argued that no one has proposed a complete ban on antibiotic usage, and that these studies would not be useful in evaluating the effects of restricted antibiotic use. However, the impact any restrictions would have on antibiotic resistance must be considered in evaluating the effectiveness of alternatives other than a complete ban. We have monitored the level and pattern of antibiotic resistance in enteric bacteria at periodic intervals during the past 13 years. Initially, the enteric bacteria of the two herds did not differ greatly in level or pattern of resistance. Though there had been no specifically planned use of antibiotics in these research herds and no one antibiotic had been used continuously at either location, antibiotics were used experimentally or as a swine producer would use them. 

The pressure to prescribe is greater in the United States than in Europe for example antibiotic usage... 

Bacterial resistance increases with antibiotic usage such that it is difficult to achieve an appropriate balance between antibiotic prescribing and minimizing resistance. Each time antibiotics are administered, the recipient is at increased risk of selection and carriage of resistant organisms that can be passed to others. This can lead to future antibiotic failure. Without antibiotic therapy, however, acute otitis media secondary to S. pneumoniae is less likely to resolve spontaneously than that from other causes. S. pneumoniae is increasingly resistant to penicillin, and penicillin-resistant S. pneumoniae is more likely to be resistant to multiple antibiotics. ... 

In addition to selecting the most appropriate antimicrobial agents, a chnician must ensure effective antibiotic usage, such as proper dosing, interval administration, optimal duration of treatment, monitoring of drug levels when appropriate, and avoidance of unwanted drug interactions. Lack of adherence to these requirements... 

Antibiotic usage has stimulated evolutionary changes that are unparalleled in recorded bio logic history. 

Widespread antibiotic usage exerts a selective pressure that acts as a driving force in the development of antibiotic resistance. The association between increased rates of antimicrobial use and resistance has been documented for nosocomial infections and resistant community acquired infections. As resistance to first-line antibiotics develops, treatment using new, broader spectrum, more expensive antibiotics increases, but is followed by the development of resistance to the new class of drugs [4]. 

Eady EA, Jones CE, Tipper JL, Cove JH, Cunliffe WJ, Layton AM (1993) Antibiotic resistant propionibacteria in acne need for policies to modify antibiotic usage. BMJ 306 555-556... 

A de-escalation of a broad-spectrum to narrow antibiotic usage, at least at the end of the infectious course, remains troublesome. This enhances costs for antibiotics as well as the rates of adverse effects, possibly over utilised drugs, and bacterial resistance. 

Antimicrobial resistance traits are genetically coded and can either be intrinsic or acquired. Intrinsic resistance is due to innately coded genes which create natural insensitivity to a particular antibiotic. Innate resistance is normally expressed by virtually all strains of that particular bacterial species. Acquired resistance is gained by previously susceptible bacteria either through mutation or horizontally obtained from other bacteria possessing such resistance via transformation, transduction, or conjugation. Acquired resistance is limited to subpopulations of a particular bacterial species and may result from selective pressure exerted by antibiotic usage. 

Howell-Jones, R.S., et al. A review of the microbiology, antibiotic usage and resistance in chronic skin wounds. J. Antimicrob. Chemother. 55(2), 143-149 (2005)... 

Nicolau DP, Nightingale CH, Quintilian R. Continuous infusion 3-lactams a pharmacodynamic approach. Infect Dis Clin Pract 1996 5(7) 432-434. Quintiliani R, Nicolau DP, Nightingale CH. Pharmacokinetic and pharmacodynamic principles in antibiotic usage. In Infectious Diseases and Antimicrobial Therapy of the Ears, Nose and Throat. Philadelphia WB Saunders, 1997 48-55. Niederman MS. Principles of antibiotic use and the selection of empiric therapy for pneumonia. In Fishman AP, Elias JA, Fishman JA, Grippi MA, Kaiser LR, Senior RM, eds. Fishman s Pulmonary Disease and Disorders. 3rd ed. New York McGraw-Hill, 1998 1939-1957. 

Hotta, K., Saito, N., Okami, Y. Studies on a new aminoglycoside antibiotic, istamycins, from an actinomycete isolated from a marine environment. JAntibiot. 1980, 33,1502-1509. Hsueh, P. R., Chen, W. H., Teng, L. J., Luh, K. T. Nosocomial infections due to methiciUin-resistant Staphylococcus aureus and vancomycin-resistant enterococci at a University Hospital in Taiwan from 1991 to 2003 resistance trends, antibiotic usage and in vitro activities of newer antimicrobial agents. Int J Antimicrob Ag. 2005,26(1), 43 9. Kharat, K., Kharat, A., Hardikar, B. P. Antimicrobial and cytotoxic activity oiStreptomyces sp. from Lonar Lake. Afr JBiotechnol. 2009, 8(23), 6645-6648. 

MARAN, Monitoring of antimicrobial resistance and antibiotic usage in animals in The Netherlands, 2004 to 2009, available at http //www. cidc-lelystad.nl. 

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