Though vaccines prevent diseases, there are many infectious dis eases without any commercial vaccines available. Hence, antibiotics are prescribed to control these diseases. Unfortunately, abuse/ misuse of antibiotics has resulted in generation of antibiotic-resistant bacteria [ 1 ]. Abuse of antibiotics is the leading cause of increased morbidity and mortality from drug- resistant microorganisms [ 2 ].

Recent studies demonstrated that abuse of antibiotics could lead to several metabolic diseases including obesity, food allergy, and autoimmune diseases [ 2 – 4 ]. Abuse of antibiotics is not restricted to patients alone, but also occurs in the food supply chain. In veterinary medicine antibiotics are used not only in the treatment and prevention of disease but also for growth promotion in food animals [ 3 ]; though many countries have banned use of antibiotics for growth promotion there are places where banning is not enforced vigorously. One of the reasons for the incidence of antibiotic-resistant bacteria is due to the uncontrolled use of antibiotics in the food supply chain. Hence there is a need to develop new and improved vaccines for animals so that they are protected during their life-span from different pathogens. Reduced use of antibiotics for the control of diseases in animals will lead to low levels of antibiotics in the food supply chain which could lead to lowering of the incidence of antibiotic resistance .

The Centers for Disease Control and Prevention (CDC) estimates that two million patients suffer from hospital-acquired infections (HAI) (nosocomial infection) every year and nearly 100,000 of them die [ 4 ]. HAIs are infections that occur more than 48 h post-admission. HAIs are caused by viral, bacterial, and fungal pathogens. HAIs are caused by viral, bacterial, and fungal pathogens. Methicillin-resistant Staphylococcus aureus (MRSA), Clostridium difficile , Pseudomonas aeruginosa , and vancomycin- resistant Enterococcus (VRE) are the major bacteria that cause HAIs. The importance of VRE is that it is capable of genetically transfer ring its resistance genes to such organisms as MRSA. Vancomycin resistant MRSA (VR-MRSA) is a major threat, because it is expected to be highly communicable and difficult to treat because of limited antibiotic therapy [ 4 ]. As yet there are no successful vaccines for the antibiotic-resistant bacterial strains. Hence there is an urgent need to develop new therapeutic strategies in the control of antibiotic resistant bacterial infectious diseases.

References
--------------

[1] Furuya EY, Lowy FD (2006) Antimicrobial- resistant bacteria in the community setting. Nat Rev Microbiol 4:36–45

[2]. Porco TC, Gao D, Scott JC, Shim E, Enanoria WT et al (2012) When does overuse of antibiotics become a tragedy of the commons? PLoS One 7(12), e46505

[3] Phillips I, Casewell M, Cox T et al (2004) Does the use of antibiotics in food animals pose a risk to human health? A critical review of published data. J Antimicrob Chemother 53:28–52

[4] Reed D, Kemmerly SA (2009) Infection control and prevention: a review of hospital- acquired infections and the economic implications. Ochsner J 9:27–31