Viruses

Viruses are not a type of bacteria! Virus comes from the Latin word for poison. Viruses are so small they can only be seen with Electron Microscope. Bacteria and other cells are large enough to be seen with a light microscope.

I. What is a virus? A.Non-cellular particle made up of genetic material (DNA or RNA) and a protein coat. Not considered to be living things! B.Parasites! CANNOT carry out life processes unless within a host (living cell). Usually host specific- infect only one type of host. C.Cannot reproduce on their own!

Bacteriophage DNA Bacterial chromosome Prophage Lytic Cycle Lysogenic Cycle Section 19-3 Figure A Lysogenic Infection Go to Section: a) Virus attaches and invades b) Virus’ DNA becomes Part of Cell’s DNA c) Cell divides c) Viral DNA separates from Cell’s DNA and becomes active d) New viruses are made e) Cell breaks open and Releases virus

T4 Bacteriophage Tobacco Mosaic Virus Influenza Virus Capsid Tail DNA Tail fiber RNA Capsid Surface proteins Envelope RNA Capsid Section 19-3 Figure Virus Structures Go to Section:

II. Viral Diseases A. Mostly caused by virus destroying cells in body. B. Cause human diseases such as polio, measles, AIDS, and the common cold C. CANNOT be treated with antibiotics D. Best Protection is prevention - Prevented by safe practices or Vaccine if available. (Vaccines must be used before infection begins)

First Symptoms: Headaches, fever, vomiting, muscle stiffness Later symptoms: Muscle weakness, pain, loss of reflexes progresses.

Franklin D Roosevelt

High fever, rash, headaches, sore throat, and runny nose

Rabies Symptoms: High fever, confusion, hallucinations, difficulty swallowing, nausea, paralysis

Bovine Spongiform Encephalopathy Mad Cow Disease

SARS- flu-like virus that leads to severe pneumonia Muscle aches, diarrhea, coughing, sneezing, headaches, fever, fatigue,

Ebola virus- liquification of internal organs and severe bleed out

Virologists A New Breed of Warriors

What Is A Virologist and What Do They Do? A virologist is someone who studies viruses. These are the people who research viruses, and sometimes find a vaccine for them. An example of a vaccine that has been discovered by a virologist is the Influenza virus. There are many levels at which a virologist can work. They range from 0 to 4.

What Is A Virologist and What Do They Do? (continued.) At level 1, a virologist works with viruses that are the most common and least harmful of viruses like the cold virus. At level 2, are more dangerous strains, such as hepatitis. At level 3, are viruses such as HIV and AIDS.

What Is A Virologist and What Do They Do? (continued.) At level 4 are the most dangerous strains such as Ebola, Hanta, and Marhburg. Virologists work with maximum protection equipment and safety standards. There are only 2 facilities in the United States with the capability of studying level four viruses, the CDC in Atlanta and USAMRIID in Maryland.

The Choices: All the things that a Virologist can study Virology divides up into many sub- categories. Some of these include: Biological Warfare Epidemology Lab Research Field Research Community Health Assessment Education and Research Public Health

School Virologists have to go to school for many years. Just like any other medical profession, it is an on-going process. There are many subjects that a virologist needs to know. Chemistry, microbiology, molecular biology, epidemology, and even virology.

Working Virologists can work in many different places, ranging from your local hospital to the Biohazard Level Four lab at the CDC to a remote region of the rainforest in Africa. Virologist can also find jobs working for pharmaceutical companies helping develop vaccines.

Salary A virologists salary ranges from a little to a whole lot. Why? It all depends on the biohazard level, the amount of research done, travel, who they are working for, and how much research has been done. A virologist can make anywhere from 30,000 to 100,000+ dollars a year.

How is a Virologist Important to the Environment? A virologist does contribute to the environment. When you see a tree with strange bumps and other such things, many times that is caused by a virus. Also, many viruses are carried by animals. If an animal is sick and spreading the disease, many times a virologist must be called in to try to make a vaccine so it can cure the disease and prevent an epidemic in both animals and people.

Common Host of diseases Finding these hosts may help with developing vaccines.

An Example: Malaria Malaria is a disease caused by parasites and is lethal unless diagnosed early. Malaria is most common in Africa and tropical climates. Symptoms of malaria include fever, shivering, pain in the joints, headache, repeated vomiting, generalized convulsions and coma. Severe anaemia (exacerbated by malaria) is often the attributable cause of death in areas with intense malaria transmission. Virologists have helped eradicate this illness worldwide!