Infectious Diseases

Infectious Disease Aka Communicable Diseases Caused by micro-organisms Parasite – lives in/on and feeds on host

Pathogens Pathogens Bacteria Virus Fungi Micro-organisms Enter the body Multiply Cause disease Bacteria Virus Fungi

Bacteria Single-cell micro-organisms Release toxins Examples Food poisoning –bacteria in food Tetanus – bacteria on objects/soil Staph

Virus Smallest parasite Enter cells and take over Multiply Cause colds/ flu HIV

Fungi Not all are harmful Some cause rashes Mushroom/ yeast/ mold/ fungi Some cause rashes Ringworm & athlete’s foot

Spreading Infectious Disease Physical contact w/ infected person Contact w/ contaminated object Environmental sources Contact w/ contaminated animals

Contaminated Animals Animal bites *Eating bad food* Rabies/ Malaria/ Bird flu HIV/ AIDS

Contaminated Object Most infections die quickly when exposed to air Some can live on objects Lice

Contact w/ Contaminated Person Skin to skin contact Sneeze/ cough Cold/ STI/ flu/ chicken pox

Environmental Sources Food/ water/ soil Lead poisoning/ food poisoning Fungi/ mold/ pathogens in water Old food left out Contaminated animals

Stages of Disease Exposure Incubation Period Prodromal Period Acute Stage Recovery Stage Convalescence Immunity

Exposure & Incubation Exposure = contact Incubation = growth/ maturation No signs/ symptoms Pathogen/ parasite grows and multiplies

Prodromal Stage Slight signs & symptoms Ex: achy/ sore/ tired Contagious!

Acute Stage Severe symptoms Most contagious Most affected

Recovery Stage Signs/ symptoms begin to decrease Temperature is reduced Feeling better

Covalescence Infection is gone Still not quite 100% Can relapse Need rest, sleep, healthy diet, antibiotics

Immunity Feel 100% Body has antibodies Cannot catch same infection

Areas with worst infections: HIV/AIDS- killed over 1.5 million per year- worst area is sub-Saharan Africa Diarrhea- killed over 1.5 million per year- mostly affects children under 5- worst areas are 3rd world countries without clean water sources Malaria is caused by a parasite that infects mosquitos. People get it from the bite of an infected mosquito. Malaria caused about 627,000 deaths in 2012. Sub-Saharan Africa took the brunt with 90 percent of all malaria deaths. Malaria is not contagious. Measles is a contagious viral disease that can be prevented through immunization. In 2010, it killed about 139,300 people around the world, according to the CDC.