Phage therapy (PT) is also called bacteriophage therapy. It uses viruses to treat bacterial infections. Bacterial viruses are called phages or bacteriophages. They only attack bacteria; phages are harmless to people, animals, and plants. Bacteriophages are the natural enemies of bacteria.

1. Phage Therapy

2. Outlines
Introduction
What Is Phage Therapy?
History of Phage Therapy
How phage therapy works
Phage use in the United States
In the food industry

3. Introduction
• Antibiotics are medicines used to prevent and treat bacterial
infections.
• Antibiotic resistance occurs when bacteria change in response to the
use of these medicines.
• Antibiotic resistance is one of the biggest threats to global health.

5. What Is Phage Therapy?
• Viruses are known to infect a wide variety of plant, animal, protists,
fungi, virus, and bacteria (bacteriophage).
• Viruses in oceans remove 20–40% of all bacterial cells each day.
• Bacteriophages are the natural enemies of bacteria.
• They only attack bacteria. phages are harmless to people, animals,
and plants.
• This therapy for disease-causing bacteria may be a useful alternative
to antibiotics.

6. lytic cycle

7. History Of Phage Therapy
• Although the idea of using bacterial viruses
therapeutically against bacterial infections
has recently gained traction in response to the
emergence of multidrug-resistant pathogens.
• The practice has been around for nearly a century,
• d’Herelle continued to pioneer phage therapy with the treatment of
dysentery, cholera, and the bubonic plague.
Félix d'Hérelle 1873 – 1949

8. How phage therapy works
• Bacteriophages kill bacteria by making them burst or lyse. This
happens when the virus infects the bacteria by injecting its genes.
• Bacteriophages can only multiply and grow inside a bacterium. Once
all the bacteria are lysed they’ll stop multiplying.

9. Phage therapy vs. antibiotics
Antibiotic Phage therapy
Antibiotics attack more than one kind of bacteria. Phage can be used to directly target disease-causing
bacteria.
Antibiotics can lead to “superbugs”. It is not known if phage therapy may trigger bacteria
to become stronger than the bacteriophage.

10. Phage Therapy Advantages
1. They may be used alone or with antibiotics and other drugs.
2. Phages work against both treatable and antibiotic-resistant bacteria.
3. They only slightly disturb normal bacteria in the body.

11. Phage Therapy Disadvantages
1. It’s not known what dose or amount of phages should be
used.
2. There may not be enough kinds of phages to treat all bacterial
infections.
3. It may be difficult to find the exact phage needed to treat an
infection.

12. Phage use in the United States
• Phage therapy isn’t yet approved for people in the United States
or in Europe. There has been experimental phage use in a few
rare cases only.

13. In the food industry
• Phage therapy is being used in the food industry, however. The U.S (FDA) has
approved of some phage mixtures to help stop bacteria from growing in foods.
Phage therapy in food prevents bacteria that can cause food poisoning
such as :
• Salmonella
• Listeria
• E. coli
• Mycobacterium tuberculosis
• Campylobacter
• Pseudomonas

14. Sources
• 1. Jawetz, Melnick, & Adelberg’s Medical MicrobiologyTwenty-Eighth Edition.
• 2. Phage Therapy: How It Works, Pros and Cons, Availability, and More (healthline.com)
• 3. Phage therapy: An alternative to antibiotics in the age of multi-drug resistance.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5547374/

15. The enemy of my enemy is my friend