Userpage partly blanked as WP:COPYARTICLE of Antimicrobial resistance except for the following section rewritten in 2013:


Role of other animals

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The emergence of antibiotic resistant microorganisms in human medicine is primarily the result of the use of antibiotics in humans, although the use of antibiotics in animals is also partly responsible[1].

Antibiotic drugs are used in animals that are used as human food, such as cattle, pigs, chickens, fish, etc. Historically, there has been extensive use of antibiotics in animal husbandry. Many of these drugs are not considered significant drugs for use in humans, either because of their lack of efficacy or purpose in humans, (such as the use of ionopores in ruminants[54]) or because that drug has gone out of use in humans (such as the decline in use of Sulfonamide (medicine) due to widespread allergic reactions and antibiotic resistance among human pathogens.) Traditionally, regulation of antibiotic use in food animals has been limited to limiting drug residues in meat, egg, and milk products, rather than concern over the development of antibiotic resistance. This mirrors the primary concerns in human medicine, where researchers and doctors were generally more concerned about effective but non-toxic doses of drugs rather than antibiotic resistance.

The resistant bacteria in animals due to antibiotic exposure can be transmitted to humans via three pathways, those being through the consumption of animal products (milk, meat, eggs, etc), from close or direct contact with animals or other humans, or through the environment.In first pathway many food preservation methods are available in order to eliminate, decrease or prevent the growth of bacteria. Evidence for the transfer of antibiotic- resistant microorganisms from animals to humans has been scant, and most evidence shows that pathogens of concern in human populations originated in humans and are maintained there, with rare cases of transference to humans,[2][3]. The use of antibiotics in animals can be divided in different use patterns depending on what is its purpose. The most accepted classification discriminates the use of antibiotics as therapeutic, prophylactic, metaphylactic and growth promotion. [4]The first three options are considered valid for therapeutic purposes in contrast with the fourth option that is considered as with non- therapeutic purposes. All these patterns predispose the exhibition of mechanisms of bacterial resistance due the proper use or misuse of antibiotics since antibiotic resistance is a natural evolutionary process.

The World Health Organization concluded that inappropriate use of antibiotics in animal husbandry is an underlying factor that contributes to the emergence and spread of antibiotic resistant germs and the use of antibiotics as growth promoters in animal feeds should be prohibited, in the absence of risk assessments. Regarding this matter, the OIE has added to the Terrestrial Animal Health Code a series of guidelines with recommendations to its members for the creation and harmonization of national antimicrobial resistance surveillance and monitoring programs[5], monitoring of the quantities of antibiotics used in animal husbandry,[6] and recommendations to ensure the proper and prudent use of antibiotic substances. Another guideline introduced in the terrestrial Animal Health Code is the implementation of methodologies that help to establish risk factors associated with this worldwide concern. The OIE concluded that risk assessments should be performed in order to assess, manage and define the possible health risks of antibiotic resistance in human and animal populations[7].

In the world, the use of antibiotics in animals is widely accepted. As in Human medicine massive quantities of antibiotics are bought without prescription and are been used in pets and livestock without veterinary supervision. Bacteria remaining in these animals are likely to be resistant to the antibiotics used, and may be passed into the environment by the excretion and secretion of materials such as milk, feces, urine, saliva, semen, lochia etc. The actual impact of these resistant organisms depends on their specific type and the animal or organism they henceforth infect. Some organisms, such as tetanus, are toxic regardless of their antibiotic resistant status. (It is useful to remember that antibiotics are not used in treatment of all diseases caused by bacteria. Tetanus, as an example, is prevented by vaccine and is extremely difficult to treat once symptoms appear.)

Footnotes

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  1. ^ The Resistance Phenomenon in Microbes and Infectious Disease Vectors: Implications for Human Health and Strategies for Containment: Workshop Summary.Institute of Medicine (US) Forum on Emerging Infections; Knobler SL, Lemon SM, Najafi M, et al., editors. Washington (DC): National Academies Press (US); 2003.[1]
  2. ^ Hurd HS, Doores S, Hayes D, Mathew A, Maurer J, Silley P, Singer RS, Jones RN. “Public health consequences of macrolide use in food animals: a deterministic risk assessment “. J Food Prot. 2004 May;67(5):980-92
  3. ^ Hurd HS, Malladi S. “A stochastic assessment of the public health risks of the use of macrolide antibiotics in food animals”. Risk Anal. 2008 Jun;28(3):695-710. doi: 10.1111/j.1539-6924.2008.01054.x
  4. ^ Joint FAO/OIE/WHO Expert Workshop on Non-Human Antimicrobial Usage and Antimicrobial Resistance: Scientific assessment[2]
  5. ^ OIE,Terrestrial Animal Health Code[3]
  6. ^ OIE,Terrestrial Animal Health Code[4]
  7. ^ OIE,Terrestrial Animal Health Code[5]