Phage therapy
Phage therapy is an innovative approach to treating bacterial infections using bacteriophages, which are specialized viruses that specifically infect and kill bacteria. Although it has been explored for many years, particularly as a potential solution to the growing issue of antibiotic resistance, phage therapy remains relatively uncommon. One of its key advantages is the ability to tailor treatments to target specific bacterial strains, allowing for more precise interventions compared to traditional antibiotics, which often affect a wide range of bacteria.
Despite its promise, the field is still in research stages, as scientists work to understand the mechanisms behind varying treatment successes and to establish appropriate dosages that minimize adverse immune responses. The preparation and administration of bacteriophages for human use also present significant challenges. As antibiotic-resistant infections become increasingly problematic, interest in phage therapy is growing, offering a potential alternative or complement to conventional antibiotic treatments. However, further studies are essential to validate its efficacy and safety, making it a topic of ongoing exploration in medical research.
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Phage therapy
Phage therapy is a treatment for bacterial infections in humans and animals. Though it has been proposed and periodically used for many years, the treatment is still considered uncommon. Phage therapy utilizes bacteriophages to kill bacteria. Bacteriophages are specific types of viruses that exclusively replicate within bacterial cells. This process typically kills bacterial cells.
Some doctors propose that phage therapy be used instead of or in addition to antibiotic treatments. Antibiotics are powerful drugs that typically kill bacteria. However, over time, some bacterial strains develop a resistance to them. Antibiotic resistant bacterial strains are incredibly difficult to treat, making them extremely deadly. However, they are still vulnerable to being killed by bacteriophages. Additionally, many bacteriophages exclusively target particular strains of bacteria. This allows doctors to tailor phage therapy treatments to specific illnesses.
Despite these advantages, doctors are still researching phage therapy. They do not yet understand why some phage therapy treatments are more successful than others. Finding the proper sized dose of bacteriophages to treat an infection is difficult, and sudden influxes of bacteriophages sometimes trigger a negative immune system response in humans. Additionally, it is particularly difficult for doctors to find and prepare doses of bacteriophages suitable for human treatments. For these reasons, phage therapy remains uncommon.
Background
Bacteriophages were discovered in 1915 by the English scientist Frederick William Twort who worked at the University of London. Bacteriophages were discovered independently in 1917 by a second scientist, Félix d’Herelle. However, many scientists were initially reluctant to believe Twort’s claims because his theories about the function of bacteria sharply contrasted those of scientists of the time.
Twort discovered that bacteriophages were specialized types of viruses. Viruses are microscopic parasites that include nucleic acid and proteins. They attack cells, piercing or passing through the cell membrane. Once inside the cell, viruses alter their host, using the cell to produce more viral proteins.
Viral infections make organisms sick. Once a virus successfully infiltrates an organism, it begins to spread from cell to cell, damaging these cells by interfering with their functions. If allowed to spread unchecked for long periods of time, viral infections can cause the death of the host. Additionally, viruses exhibit behaviors that allow them to spread to other people.
Bacteriophages are specialized viruses that attack bacteria. They function similarly to traditional viruses. Some bacteriophages infect a bacterium and then reproduce inside the bacterium, causing it to rupture. This is called a lytic lifecycle. Other bacteriophages cause themselves to be reproduced alongside the host cell, tricking the host into creating more copies of the virus, a process called a lysogenic lifecycle. Still other bacteriophages can alternate between lyric and lysogenic lifestyles. Like other viruses, bacteriophages are unable to reproduce without infecting a host cell. For this reason, bacteriophage infections tend not to survive for long without access to bacteria.
Overview
Phage therapy involves the intentional use of bacteriophages to combat bacteria. During the process of replication, bacteriophages kill bacteria. After all the usable bacteria have been killed, bacteriophages can lie dormant, only waking to attack more bacteria as they become available.
Some scientists have proposed that phage therapy be used instead of antibiotics. Antibiotics are powerful drugs that are used to kill or slow the growth of bacteria. They are commonly used to treat bacterial infections.
Many types of antibiotics exist. Though the first antibiotic was penicillin, other varieties have been discovered and manufactured. If a dosage of antibiotics fails to kill all the bacteria causing an infection, bacteria with some natural resistance to the antibiotic may survive. These bacteria reproduce, passing on that resistance to the next generation. This creates an entire strain of bacteria that is resistant to a particular antibiotic. These infections may be particularly difficult for doctors to treat. For this reason, doctors typically recommend that patients take the entire dose of antibiotics, even after symptoms of the infection have subsided. However, despite these precautions, some strains of antibiotic resistant infections have developed.
Untreatable bacterial strains, meaning strains resistant to all known types of antibiotics, can quickly kill many human beings. Some scientists have proposed that phage therapy be used as a means to treat antibiotic infections. Additionally, bacteriophages can be used alongside traditional antibiotics to increase the odds of a successful treatment.
In many cases, antibiotics kill bacteria indiscriminately. Because many of the bacteria in the human body are necessary for its function, such as the bacteria that aid in digestion, repeated doses of antibiotics can significantly damage the body. Bacteriophages, on the other hand, often target specific strains of bacteria. For example, strep bacteriophages can be used to target and kill the bacteria that cause strep throat infections. A wide variety of bacteriophages exist, allowing doctors to specifically target many common infections.
Unfortunately, phage therapy is not yet common. Doctors still do not know which varieties of phages are best for treating certain infections. They are also unsure of the negative side effects the treatment may cause. Sometimes a sudden increase in bacteriophages can trigger the human immune system, causing it to overreact or harm the body. Additionally, doctors still find it difficult to prepare safe, controlled bacteriophage treatments for humans and animals. For these reasons, as well as many others, phage therapy will remain an uncommon treatment until more research is conducted.
Bibliography
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