WHAT MAKES US SICK?

VIRUSES, BACTERIA, FUNGI, PARASITES AND OTHER BUGS

MICROBES THAT CAUSE DISEASE ARE CALLED “PATHOGENS”

Types of bacteria

Arrangements of Bacteria

Diplococcus

Streptococcus

Tetrad

Sarcina

Staphylococcus

Bacterial Diseases

Tooth decay Lyme disease Tetanus Tuberculosis Salmonella Pneumonia Cholera

Viruses: Are they alive?

Viruses have No membranes No cytoplasm No source of energy

They do haveA protein coat or capsidDNA or RNA

rabies virus herpes virus

bacteriophage

tobaccomosaic plant virusmeasles virus

Copyright © 2005 Pearson Prentice Hall, Inc.

Viruses vary greatly in size and shape!

If a bacterium were the size of a football field, one of these viruses would be the width of a human hair compared to it!!!!

proteins

proteincoat

envelope(lipid bilayer)

genetic material(viral RNA) coated with protein

Life cycles of viruses

Two life cycles: Lysogenic – the viral DNA is inserted into

the host cells DNA and replicates with the host cell. The organism has no symptoms of the virus in this stage

Lytic – The virus replicates itself using the cells ribosomes, amino acids, and nucleotides. It is reassembled inside the host cell and bursts (lyses) the host cell. The organims that is infected has symptoms of the virus in this stage

Treatment for viruses

Once you get a virus it is yours to keep

The treatment is to prevent getting a virus by giving a vaccination against the virus

Childhood vaccinations

Diphtheria

Diphtheria is a virus that attacks the throat and heart. It can lead to heart failure and death

Tetanus

Tetanus is also called “lockjaw”. It can lead to severe muscle spasms and death

Polio Vaccine

Can be given orally or injected Given 4 times Polio can cause muscle pain and

paralysis of one or both legs or arms. It can also paralyze the muscles used to

breathe and swallow. It can lead to death

Measles

Causes fever, rash, cough, runny nose, and watery eyes

Can also cause ear infections and pneumonia

Can lead to brain swelling and death if untreated

Chicken Pox: Varicella Virus

HBV: Hepatitis Virus

Woman with liver cancer caused by the hepatitis virus

Fungal Diseases

Athlete’s Foot Yeast infections Ringworm Food spoilage

Transmission

Airborne (coughing, sneezing) Physical contact Contaminated water/food Infected animals Sexually Blood borne