A brief history of Mastitis and its treatment with Bacteriophage against Staphylococcus aureus

The secretion of liquid from mammary glands is termed as milk. During the initial stages of life, it is the only source of food for mammals. Man has learned to domesticate animals for milk purposes; these animals are buffaloes, goats, cows, and camels. Besides its nutritional availability, consumers are also at risk of diseases due to antimicrobial residues and zoonotic pathogens. Raw milk and its derivatives favor the growth of many microorganisms, considered as the significant source of Staphylococcal infection in man. The 5% of Staphylococcal outbreaks in Europe were due to milk and other dairy products. In the last few years, multidrug-resistant LivestockAssociated Methicillin-Resistant Staphylococcus aureus (LA-MRSA) has been reported worldwide. Its increase is a significant concern from a public health perspective. Phage therapy proved to be successful for the treatment of bacterial infections in animal models and human patients. TEM126 can be used and selected for phage therapy as an antitherapeutic agent against Staphylococcus aureus infections. This review mainly focuses on the source of mastitis infect ion and their consequences and also discusses their treatment with bacteriophages.


Introduction
Mastitis can be referred to as "The Inflammation of the mammary gland" It may be moderate or very severe. The presence of mastitis can change the texture of milk and microbiological contents. There will be a significant loss by this disease in this herd. The loss will be due to a reduction in milk production. In simple words, mass milk should be discarded. A primary microorganism that is involved in the outcome of mastitis is "Algae" mycoplas ma, yeast, and bacteria. The bacterial pathogens involved in this disease are (Staphylococcus aureus, Streptococcus dysglactiae, Streptococcus uberis, Streptococcus agalactia, and Escherichia coli). The most common causative agent of mastitis in caprine and other dairy animals is Staphylococcus aureus [1]. Milk contains all necessary nutrients and energy materials for the proper growth of infants. After India and China, Pakistan is ranked third worldwide to produce the goat [poor man's cow]. Goat milk provides the necessary nutrients for rural families and underprivileged areas. In Pakistan, about 71% of milk is produced from buffaloes, 24% by cattle, and 5% by sheep and goat. Total milk production through sheep and goat is almost 17.69 million-tonne in Pakistan. As compared to the milk of sheep and goat, human and cow milk contains less fat and protein. One-liter milk of goat contains 32g of protein and preferably very good for children up to 11 years of age. It includes a high level of isoleucine, cysteine, tyrosine, lysine, valine, and threonine as compared to cow milk. Milk is rich in fats, proteins, carbohydrates, vitamins, and minerals; hence it is a portion of very nutritional food [2]. Besides its healthy availability, consumers are also at risk of diseases due to antimicrobial residues and zoonotic pathogens. Raw milk and its derivatives favor the growth of many microorganis ms, considered as the significant source of staphylococcal infection in man. 5% of Staphylococcal outbreaks in Europe were due to milk and other dairy products. The presence of udder infection, contamina tio n during and after milking, and adulteration are factors that can lower the quality of milk. Milking through contaminated milk machines, clothes, and hands of milkman can aid the contamination of bacteria. Major organisms involved in infection in the mammary glands are Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis. Streptococcus agalactiae and Escherichia coli. [3]. Mastitis is the most frequent infectio us disease in dairy cows and is the global problem in dairy herds. It is accountable for a significant loss in dairy products because more than 100 microbial species have been isolated from cows' mammary glands, but a small number of these organisms cause mastitis. Staphylococcus aureus is one of them responsible for the leading cause of mastitis in dairy cows. These organisms are generally called "contagious" or "environmental" based on their reservoir and source and transmission mode. The term contagious means that the infected mammar y glands are the primary source of infectio n, which is transferred to a healthy person by milking, from the equipment of milk ing, towels, and the milkman [4]. The term "environmental" refers to the mastitis that the organisms present other than the area of mammary glands such as Pasture, bedding, and various surfaces. Successive mud, soil, and moisture contribute as a significant factor in the spreading of these organis ms. Successful control of "environmenta l" mastitis is based on maintaining a dry living and clean area, whereas successful control of "contagious" mastitis is based on minimizing exposure to teats contaminated with pathogens found in the milk of infected cows. As I quoted earlier, Staphylococcus aureus is the foremost and frequent contagious pathogen that is causing mastitis. Cows with infection are the primary cause of contamination of Staphylococcus. Aureus in raw milk. In particular, cows with subclinica l Staph. aureus mastitis infections can shed a large number of Staph. aureus organisms in their milk. [5]. The Most critical pathogen is causing skin infection, food poisoning, nausea, diarrhea, and cramps in humans. Spreading and the outbreak of disease is due to the production of enterotoxins produced by Staphylococcus aureus. Five different classes of enterotoxins produced by staphylococcus abuses have been reported, but their mechanism of precluding food poisoning and virulence is not cleared yet. By direct involvement of virulent Bactria and by internet contamination, Staphylococcus aureus can contaminate the milk [6].

Staphylococcus aureus resistance
Staphylococci are Gram-positive bacteria with a range of diameter 0.5 -1.5 μm, which can be divided into more than one plane and form grape-like clusters that are why individual cocci characterize them. Genus Staphylococcus has 32 species and eight subspecies. The Staphylococci are nonspore-forming, non-motile facultative anaerobes that can be grown by fermenta tio n or aerobic respiration. Generally, they require an organic source of nitrogen, given by 5 to 12 essential amino acids, e.g., valine, arginine, and B vitamins with nicotina mide and thiamine. These bacteria are also resistant to high salt concentratio n. Staphylococcus aureus is a commensal, nonmotile, non-spore-forming, gram-positive, and normally a member of the human body's normal microbiota, especially in the upper respiratory tract and skin. About 60% of the population is the carrier, while 20% are normally colonized with this bacterium. Staphylococcus aureus can evade the immune response by capsular polysaccharides protein A and leukocyte specific toxins and the ability to grow as a biofilm [9]. The human population's normal microbiota contains 20% to 30% Staphylococcus aureus found in nostrils, skin flora, and normal inhabitant of women's lower reproductive tract. Although this bacterium is a normal microbiota member, it can be an opportunistic pathogen and become a common cause of skin infection, abscess, respiratory infection such as sinusitis, and food poisoning [10]. Staphylococcus aureus is involved in several diseases in humans and animals, and pathogenicity is related to different genetic characteristics involved in virulence are Immune evasion, invasive capacity, and antibiotic resistance. S. aureus has so much importance as an etiological agent in dairy ruminants because of causing both clinica l and subclinical mastitis and is involved in economic losses due to a reduction in milk production and quality. In the last few years, multidrug-resistant livestock-associated methicillin-resistant S. aureus [LA-MRSA] has been reported worldwide. Its increase is a great concern from a public health perspective [11]. Due to the production of enterotoxin, Staphylococcus aureus is a major human pathogen in causing food poisoning. Previously published studies carried out in Italy revealed that 39% of samples of raw milk and raw milk cheese have Staphylococcus aureus, and 21% carried enterotoxin genes. The most popular cheese in Colombia is double cream, and its consumption is more than 30%. It is also fresh cheese and quite similar to mozzare lla and other curd cheese, which are traditiona lly made from raw milk. Research  . But these studies were not differentiating between organic and conventional herds. People who are working on farms have a greater chance of carrying resistant Staphylococcus aureus into the health care system during the treatment. However, the risk of MRSA through milk consumption is low due to milk's heat treatment before exporting to the market. But this estimation may differ from the consumption of milk, which is present in an open market for the people and products made from raw milk because this raw milk and raw milk products expose the consumers to many viable bacteria. Until now, no reports have been published indicating the spread of livestock-associated methicillin-resis ta nt Staphylococcus aureus [LA-MRSA] to humans via milk [17]. In the United States, MDR [multidr ugresistant] organisms cause at least more than 2 million infections and lead to 23,000 deaths every year. Methicillin-resis ta nt Staphylococcus aureus is now an MDR organism and is resistant to several antibiotics and is a major concern for the community The major and great concern that can threaten the societies is infection through MRSA and OSMRSA due to these organisms' public health being at risk [26]. Staphylococcus aureus in the human microbiota, but it is cells involved in several diseases and infections in humans and animals, and most importantly, it is causing inflammatory infection in dairy animals. It is involved in both clinic and subclinica l diseases. This study is designed to identity the circulation and prevalence of methicillinresistant Staphylococcus aureus [MRSA]. MRSA was isolated from Italian dairy sheep. Milk was collected from build tank milk for the isolation of MRSA. Three people were also used for sampling purposes, which was in close contact with these animals. First isolation was done in 2012, and after two years of first isolation same multidr ugresistant bacteria, especially a strain of MRSA, was identified. About a century ago, in 1917, d'Herelle had given the term Bacteriophages to the viruses that infect or kill the bacteria late he introduced the term phage therapy. These are the organisms [viruses] that lyse the bacterial cells only and do not harm another cell eukaryotic cell. This was the first scientist that used the term phage therapy. Due to its therapeutic action to kill many bacterial cells. And to cure and treat bacterial disease. He used phage therapy experimentally to control dysentery, and after a few hours during this period, he introduced bacteriophages to 12 years old boy, and luckily, he showed a proper recovery from dysentery. In the normal functioning of the patient, there were no side effects of phage therapy [36]. After the discovery and termed introduced by d'Herelle, many companies had strutted phage products production in response lie bacterial disease. But this was not more than just ten years of era. And alexander fleming discovered the first penicillin in 1928. And the response of completely changed from phage therapy to antibiotics in response to cure the bacterial disease of Europe, especially eastern Europe phage therapy, is still being practiced. Different institutes and Research centers like Eliavia Institute of bacteriophage, Hirschfeld Institute, Poland, and Tbilisi Georgia. As the resistance against antibiotics has been discovered and being discovered bacteriophages are now considered as bioagent to Important control treat Infections [37]. An increase in Staphylococcus aureus resistance against methicillin and vancomycin and different antibiotics and this antibiotic resistance becomes a serious problem for bacterial infections in hospitals and community environments. phage therapy proved to be successful for the treatment of bacterial infections in animal models and human patients. Bacteriophages are the viruses that infect or kill the bacteria. Bacteriophages were discovered by two different scientists, in 1915 by a British pathologist Fredrick twort and in 1917 by Félix d'Hérelle; a Félix d'Hérelle first used bacteriophages as a therapeutic agent against bacterial infection [38]. Besides the successful results, this therapy was not gained as much importance because of less quality, less differentiation, and antibiotics discovery. Antibiotics gained much more importance after their discovery, but soon MDR [multidrug-resistant bacteria] has emerged, and in 1980, phage therapy is gaining importance because it has some advantages over antibiotics. [ [40]. Recent studies also revealed that phages from the Myovir idae family are safe for therapeutic applicatio ns. First, phage therapy was done against Staphylococcus aureus skin infectio ns. Phages were reported in treating bacterial diseases such as staphylococcal lung infection, staphylococcal skin infectio n, urinary tract infections, neonatal sepsis, and diabetic foot as a complication of diabetes. Bacteriophages were also very effective against biofilms and suggested as effective biofilm agents [41]. Bacteriophage infection cycle starts with the adsorption of the virus on the surface of bacteria with spikes or tail fibers' help. In gram-negative bacteria, lipopolysaccharides, oligosaccharides, and proteins can be used for the attachment of bacteriophage. Grampositive bacteria offer a very different site for bacteriophages' attachment to bacteria because it has murine in its cell wall. After the non-reversible adhesion, the bacteriophage's genome must cross the three bacteria barriers to reach the genome of bacteria for the transcription and translatio n process [42]. First of all, the virus releases enzymes on the bacterial surface by its tail fibers rather than injecting DNA into the bacterial cell. There will be high metabolic activity in bacteria; after getting enough metabolic activities genome starts to replicate. There were two types of bacteriophages, temperate phage, which relies on the bacterial genome, while virule nt phage codes on its machinery. In this way, virulent bacteriophages are released from the bacterial cell and will be ready to infect the next bacteria [43]. Lytic bacteriophages are significantly used in phage therapy because of their ability to lyse the bacterial cell temperate bacteriophages. They rely on the bacterial cell's genome and do not involve in the bacterial cell's lysis MRSA's problem has become a significa nt concern while it is spreading from hospitals out into the community. In Pakistan, its prevalence has been increasing from 5% to 51% only from 1989 to 2003. So, there is a need for bacteriophage therapy. This study's main objective is to isolate bacteriophages from sewage water against Staphylococcus aureus involved in the number of infectio ns [44]. It is thought that there are ten times more bacteriophages than bacteria, which leads to a more diverse and most expanded form of life on earth. Phage therapy has many more advantages as compared to antibiotic treatment. Phages are bactericidal [that kill the bacteria] in nature. More specific as compared to antibiotics. Due to bactericida l, there is a meager chance of survival of bacteria after phage infection. More importantly, phage therapy is economical and versatile because of several antibiotics and its boosting antibacterial spectrum [46]. Phage therapy has much more advantages over antibiotic therapy because phage isolation is [

Morphological families of bacteriophage
All the genera of bacteria are associated with bacteriophages. Due to their characteristics, these viruses are divided into differe nt families. These characteristics that differed families include phylogeny, host-ranging chemical sensitive morphogenesis physical sensitive plaque morphology strategies of infection, and the host cell properties and environmental [52]. The international committee on taxonomy of viruses has been recognized only three orders of viruses. These three orders include 214 genera and 61 families. But as the study proceeds, ICTV acknowledged only one order, consisting of 13 families and 31 genera. Bacteriophages infection the total 140 bacterial genera all include archaea and eubacteria etc. Usually, phages have tailed polyhedral, pleomorphic, or filamento us symmetry.
There are only a few bacteriophages that include ds RNA SSRNA or single-stranded DNA most of the bacteriophages that include double-stranded DNA their genetic material bacteriophages which have filamentous or pleomorphic symmetry are classified into families. These ten families contained 208 viruses, and about only 3.7% is the bacteriophages among these viruses. Besides The genes involved in the host's genomic integration present on the strands and genes are usually located at all genes [37]. There is much difference while studying the genome of the podoviridae family. From that difference, one is present in small numbers of ORFs. It consists of functional segments that include genes that encode the lysis, capsid genes, and genes for DNA packaging. Suppose we compare the Podoviridae family with the siphoviridae family. Siphovir idae gene segments are not adequately defined because the genes for lysis and genes encode tail overlying to each other in siphoviridae. A gene called a cfr gene produces resistance against lincosamide, oxazolidino nes, streptogramin A, and phenicols. This cfr gene is majorly present and associated with the coagulase-negative staphylococci from animals. There are very few bacteria [MRSA] Methicillin-resistant Staphylococcus aureus in which the cfr gene is described. They designed a study in which they describe a cfr gene in MRSA isolates, which was PVL (panton-valentine leucocidin) positive. DNA microarray technique was used to screen PVL positive isolates. The DNA microarray technique detects virulence genes, antimicrobial resistance genes, and typing markers. Molecular analysis revealed a conjugated plasmid of 45kb, which is associated with phenicol resistance. A multidrug-resistant CFR positive variant has emerged in MRSA [56]. Phage endolysin Endolysin are the enzymes which are released by bacteriophages are used for the cleavage of peptidoglycan bond present in the cell wall of bacteria. These endolysin enzymes used for the cleavage of a bacterial cell are produced at the end stage of the lytic cycle. Endolysin enzymes target the peptidoglycan bond, which is highly unique and conserved, so there is a minimal chance of getting resistance against endolysin enzymes. Host bacterial pathogens are stopped by phage endolysin by the characteristics of cleaving peptidoglyca n; these enzymes can be used as an antibacter ia l against the gram-positive bacterium [57]. Small proteins that are present on the membrane are holin protein. This protein has 34 families and three topological classes. Genome sequences can analyze the holing genes and endolysins, which are present in bacteriophages.
Double-stranded DNA bacteriophages need muralytic enzymes and a holin system to lyse an infected bacterial cell. The gene which encodes endolysin is indicated as the 'R' gene, and the gene which encodes the holin system of bacteriophage is marked as the 'S' gene. Both genes are used for the lysis of bacterial cell because 'S' gene increases the permeability, and 'R' gene attacks the cell wall of host bacterial cell, and both leads to the bacterial cell lysis [58,59].

Conclusion
The community's public health is at risk due to the contamination of different toxic organisms in food. Staphylococcus aureus is causing many diseases to humans, includ ing skin diseases and majorly food poisoning due to enterotoxins production. Further, it is getting resistance day by day to differe nt antibiotics. Phage therapy proved to be successful for treating bacterial infections in animal models, and for human patients, TEM126 can be used and selected for phage therapy as an antitherapeutic agent against Staphylococcus aureus infections. For the curing of Infection, you must have controlled monitoring patterns. Infect the residues of antibiotics from animals that can be transferred to human beings by consuming milk. This can cause resistance against microorganisms.
The use of these bacteriophages soon will be a preventative agent that can use these bacteriophages to kill bacteria, especially Staphylococcus aureus, to make milk free from bacteria. These approaches can open the doors to the devastating lives of bacteriophages. So, we can use these bacteriophages in differe nt fields of life. But it needs a comprehens ive study on bacteriophage, which may take some time to use them as a preventative agent.