51.-60 Essay

How do lytic and temperate lysogenic bacteriophages differ? Why is it important to understand the difference?

They differ by their lifecycle. Lytic Bacteriophages immediately penetrate a cell, begin reproducing and then kill the host. Temperate phages can remain inside a cell without immediately beginning the replication process. The DNA becomes incorporated into the bacteria cell and will be copied as the bacteria reproduce. This difference is important to understand because it can help us realize how bacteria have evolved over the years. Viruses have been incorporating their DNA into bacteria for many years and have therefore influenced their evolution. 10 to 20% of their DNA comes from phages. These differences are also important to understand because they affect human beings. During a lysogenic conversion, these bacteria can become toxic to humans.

What is a prophage?A prophage is the inactive state of a lysogenic bacteriophage.

What is conversion?When a bacteria cell acquires a new trait from a lysogenic bacteriophage.

Microbiology A Systems Approach Marjorie Kelly Cowan

61-70Describe why it is easier to treat a bacterial infection than a fungal, viral or Protozoan infection.

Bacterial infections are easily treatable because of the unique composition of bacterial cells. Bacterial cells have different ribosomes than eukaryotic cells have. They also use different chemicals than do Eukaryotic cells. It is therefore easier to identify toxins for bacteria that will not affect the Eukaryotic cells of the human body. It is difficult to treat a Protozoan and a fungal infection because they are Eukaryotic cells with many similarities to human cells. Therefore, it is very difficult to find agents that will only attack the infectious cells and not the human cells in the process. Viruses are even more difficult to treat. The way modern medicine tackles infections is simply by attacking the metabolic processes of infectious agents. Unfortunately, Viruses do not have any metabolic processes. Viruses only have a handful of genes. Therefore there are only a few targets that drugs can attack. A virus will also mutate very quickly and therefore they can rapidly become resistant to a drug.

http://www.chmed.com/mod.php?mod=userpage&page_id=37

There are two main classes of bacterial disinfectants. Antimicrobial drugs that either kill microbes (microbiocidal) or prevent the growth of microbes (microbiostatic). They can be obtained from natural sources or they can be synthesized. Antibiotics attack bacteria. They

can attack the bacteria cell walls or prevent the bacteria from the translation process of converting RNA to proteins. The antibiotics can do this by binding to ribosomes. However, antibiotics also attack the bacteria that have a symbiotic relationship with humans. Antivirals attack viruses by preventing them from attaching to human cells. They can also stop viruses from reproducing or leaving a host cell. These drugs have little effects on the host. Antifungal drugs work by attacking the little differences that exist between a human cell and a fungal cell. They are very dangerous to the host and can kill the host if the dugs are not properly used. http://en.wikipedia.org/wiki/Antimicrobial

91-100: Essay 1

a. During the Ebola video several breaks in Infection control Practices occurred which could have resulted in more infections and deaths. Describe at least 3.

One Mistake that was made was the fact that a blood transfusion was given to a sick nurse. This could have resulted in many diseases being transferred to her and could have resulted in death. Because of the conditions in Zaire, needles were also constantly reused and this resulted in more infections of Ebola. Many residents also would not comply with doctors and would keep many ill people in their homes causing more infections. Also because many of the people in Zaire were illiterate, it was difficult to educate people on this disease and how to prevent infection. The doctors treating some of these patients were also not adequately protected. This could result in the infection of doctors.

b. When the blood transfusion was attempted on the sick nurse, which doctors did you side with?

c. Why? d. Justify your position.

I sided with the doctors who gave the transfusions. Many people believed this was wrong to do since a transfusion has never been proven to work but I believe since the nurse agreed to the transfusion, it was ok to perform it. The chances of her dying from Ebola were very high. About 80% of the people infected with Ebola died. This was clearly better than doing nothing. Some of the doctors who gave the transfusions to the other patients believed they were working and 7 out of the 8 transfusions survived Ebola. Bonus Question: (1)

Why is it important to know the point of entry of an infectious agent or the target organ when testing the efficacy of a vaccine?

Infectious agents are very specialized to specific areas of the human body. Therefore the human body has also adapted to defending itself from certain agents in certain areas. Which is why it is important to know the target of the agent. So that the vaccine will mimic the actual agent and the immune system will be ready to attack the agent at that specific location. Microbiology A Systems Approach Marjorie Kelly Cowan

What are some of the criteria that must be met when developing a vaccine?

The vaccine must be first tested on adults with low risk of complications. If the immune system of these adults does not fight the vaccine, it becomes a failure and is taken back to the drawing board. The vaccine is then tested on a few people of the target audience. If complications occur, the vaccine again goes back to the drawing board. If successful, the vaccine is tested on thousands of people from many different environments. If safe then the vaccine is approved and sold. Of course many drug companies have to fund the research before the process starts.

http://health.howstuffworks.com/wellness/preventive-care/vaccine4.htm