Phage Therapy in Livestock and Companion Animals

Abstract

The irrational use of antibiotics has led to a high emergence of multi-drug resistant (MDR) bacteria. The traditional overuse of antibiotics in the animal feed industry plays a crucial role in the emergence of these pathogens that pose both economic and health problems. In addition, antibiotics have also recently experienced an increase to treat companion animal infections, promoting the emergence of MDR bacteria in pets, which can reach humans. Phages have been proposed as an alternative for antibiotics for the treatment of livestock and companion animal infections due to their multiple advantages as adaptative drugs, such as their ability to evolve, to multiply at the site of infections, and their high specificity. Moreover, phage-derived enzymes may also be an interesting approach. However, the lack of regulation for this type of pharmaceutical hinders its potential commercialization. In this review, we summarize the main recent studies on phage therapy in livestock and companion animals, providing an insight into current advances in this area and the future of treatments for bacterial infections.

Microencapsulated phages show prolonged stability in gastrointestinal environments and high therapeutic efficiency to treat Escherichia coli O157:H7 infection

“…Phages are very effective and have been successfully used to prevent and treat bacterial infections in animals [ 14 – 16 ]. Although phages can be administered in a variety of ways, including via parenteral, topical, oral and inhaled routes, by lavage and through eye and nose drops [ 13 , 17 ], the current problem is that phages lack suitable dosage forms.…”

Antimicrobial Resistance in Companion Animals: A New Challenge for the One Health Approach in the European Union

“…Bacteriophages (or “phages”) are viruses that possess the natural characteristic of specifically targeting and killing bacteria [ 49 ]. One of the advantages of phages is their ability to adapt to bacterial strains due to decades of co-evolution, which is why they are considered ‘adaptive drugs’ [ 49 ]. Moreover, their ability to lyse different bacteria strains has been reported.…”

“…Moreover, their ability to lyse different bacteria strains has been reported. Although phages are considered a promising tool as an alternative to antibiotics, in veterinary medicine studies have been focused on food-producing animals, so there are only a few in vivo studies in companion animals [ 49 , 50 ].…”

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): antimicrobial‐resistant Escherichia coli in dogs and cats, horses, swine, poultry, cattle, sheep and goats

“…Ampicillin, amoxicillin, amoxicillin with clavulanic acid and sulfonamides with trimethoprim are commonly recommended as first‐choice drugs for UTIs, and fluoroquinolones and cephalexin for other infections. Bacteriophage therapy to combat canine and feline E. coli UTIs seems to be a promising strategy as therapeutic agents, yet the lack of regulation for this type of pharmaceutical hinders its potential commercialisation (Ferriol‐González and Domingo‐Calap, 2021 ). Other therapeutic strategies, such as the use of probiotics and antimicrobial peptides, are considered against UTIs, yet limited success has been achieved.…”