ABSTRACT
Staphylococcus aureus infections have already presented a substantial public health challenge, encompassing different clinical manifestations, ranging from bacteremia to sepsis and multi-organ failures. Among these infections, methicillin-resistant S. aureus (MRSA) is particularly alarming due to its well-documented resistance to multiple classes of antibiotics, contributing significantly to global mortality rates. Consequently, the urgent need for effective treatment options has prompted a growing interest in exploring phage therapy as a potential non-antibiotic treatment against MRSA infections. Phages represent a class of highly specific bacterial viruses known for their ability to infect certain bacterial strains. This review paper explores the clinical potential of phages as a treatment for MRSA infections due to their low toxicity and auto-dosing capabilities. The paper also discusses the synergistic effect of phage-antibiotic combination (PAC) and the promising results from in vitro and animal model studies, which could lead to extensive human clinical trials. However, clinicians need to establish and adhere to standard protocols governing phage administration and implementation. Prominent clinical trials are needed to develop and advance phage therapy as a non-antibiotic therapy intervention, meeting regulatory guidelines, logistical requirements, and ethical considerations, potentially revolutionizing the treatment of MRSA infections.
ABSTRACT
Seafood is one of the essential sources of nutrients for the human diet. However, they can be subject to contamination and can cause foodborne illnesses, including scombroid fish poisoning caused by histamine. Many microorganisms can produce enzymes that eventually decompose endogenous histidine to histamine in postmortem fish muscles and tissues. One of these is histamine-forming bacteria (HFB), primarily found in the gills, gut, and skin of fishes. Previous studies linked a plethora of Gram-negative HFB including Morganella spp. and Photobacterium spp. to scombroid fish poisoning from many types of seafood, especially the Scombridae family. These bacteria possess the hdc gene to produce histidine decarboxylase enzyme. It was reported that Gram-negative HFB produced 6345 ppm in tuna and 1223 ppm in Spanish mackerel. Interestingly, Gram-positive HFB have been isolated in the seafood samples with lower histamine levels. It suggests that Gram-negative HFB are the major contributor to the accumulation of histamine in seafood. Several analytical methods are available to detect and identify HFB and their histamine metabolites from seafood substrates. Rapid test kits can be used in food production settings for early detection of histamine to avoid food intoxication. Furthermore, high hydrostatic pressure and irradiation treatment could prevent the proliferation of HFB and inactivate the existing histidine decarboxylase (HDC) activity. As demonstrated in different seafood model systems, the HDC activity was deactivated at a maximum high hydrostatic pressure level of 400 MPa. The complete inactivation of HFB was achieved by gamma irradiation at a dose of 4.0 kGy. Other postharvest treatments, like enzymatic degradation and electrolyzed oxidizing water, were studied as sustainable methods for bacterial growth prevention and enzyme inactivation. However, other HFB react differently to these treatment conditions, and further studies are recommended.
