INFECTIOUS DISEASES

A disease is any condition which stops a part of the body from working properly

Diseases may be classified as :

    Non-Infectious - can’t be spread from one person to another (eg. diabetes, cancer, arthritis)

    Infectious - can be spread from one person to another (eg. tuberculosis, malaria, colds, flu)

Infectious diseases tend to be caused by living organisms. If these organisms are so small that they cannot be see without a microscope, they are called microbes. Organisms which cause disease are called pathogens
and the individual they infect is called the host

The major categories of microbes are :

Viruses -    eg. cold, flu, herpes, chickenpox, hepatitis, HIV

Bacteria -    eg. Streptococcus, Staphylococcus, tetanus, Salmonella)

Fungi -        eg. Tinea, Thrush

Protozoa -     eg. Giardia, Amoebic Dysentery, Malaria

Helminths -    (worms) eg. Roundworm, Tapeworm, Flukes

Arthropods - eg. lice, mites

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