Infectious Disease Notes What is disease A disease

Infectious Disease Notes

What is disease? • A disease is any change, besides an injury that affects the normal functioning of the body.

What is an infectious disease? • An infectious disease is any disease that can be transmitted from one person to another person.

What is a pathogen? • A pathogen is any agent that can cause disease. • In humans, pathogens fall in six categories. – – – Bacteria Viruses Protists Worms Fungi Prions

What is a bacteria? • Bacteria are single-celled organisms that are prokaryotic. – Prokaryotic means ‘without a nucleus’ • Most bacteria do not harm humans. • Many bacteria are helpful to humans such as the bacteria in the intestinal tract. • Some bacteria cause infections.

What is bacteria? . • Antibiotics kill bacteria in a wide variety of ways. • It is very important to finish all antibiotics as prescribed by your doctor.

What are some dieases caused by bacteria? • • • Most infected cuts and scrapes Urinary tract infection Strep throat Diptheria Pneumonia

What is a virus? • A virus is a small infectious agent that can only reproduce inside of living things. – Not alive, but can reproduce inside of living things. • Viruses cannot be killed by antibiotics. • Viruses are killed by antiviral medications; currently, we do not have many antiviral medications.

What are some viral diseases? • • Common cold Stomach flu Influenza Chickenpox Measles Smallpox Polio

What is a protist? • Protists are one-celled organisms that have a nucleus. • Common source of infections from drinking contaminated water. – In Michigan, Giardia lamblia causes diarrhea in campers who drink ground water. – Malaria is caused by a protist

What is a worm? • People can be infected by flatworms and roundworms. – Tapeworms attach to the digestive system of humans and cause severe malnourishment. – Hookworms do the same thing as tapeworms.

What is a fungi? • Fungi are multicellular organisms with a cell wall that do not use photosynthesis. – Fungi do not cause many diseases in humans, but can be very difficult to treat when infections occur. • Yeast infections (including thrush) • Athlete’s foot • Jock itch

What is a prion? • A prion is a protein that is folded incorrectly and causes proteins nearby to fold incorrectly. – This can eventually kill the cell. • Very, very rare – Mad cow disease – Cruetzfield-Jakob disease