Infectious DiseasesChapter 11.3: page 460-442Chapter 12.1: page 492-496

•7.03: Students will look trends to determine how an infectious disease may spread.

•VOCABULARY:▫Infectious disease▫Carrier▫Vector

•Have you ever been sick before? What do you know about how the disease you had spread?

What is an infectious disease?•An infectious disease is an illness that passes from one organism to another.

•Most infectious diseases are caused by bacteria, viruses,

fungi, or protists.

•EXAMPLES:▫Strep throat▫A cold or flue▫Chicken pox▫Tetanus▫Athlete’s foot▫African sleeping

sickness

Which is NOT an example of an infectious disease?•A) AIDS•B) Tuberculosis•C) Brown hair•D) Pneumonia

How do infectious diseases spread?•Diseases can spread by:▫Contact with an infected

person such as touching, hugging, kissing, sneezes, or coughs

▫Contact with a contaminated object.

▫Contact with an infected animal.

▫Soil, food, or water. EXAMPLE: Eating meat that has not been cooked properly can cause food poisoning.

A person gets malaria from a mosquito. This illness was caused by ___.•A) Contact with an infected

person.•B) Contact with an infected

animal.•C) Contact with an infected

object.•D) Contact with contaminated

food, soil, or water.

How is cholera likely spread?

A) AnimalsB) SoilC) WaterD)Undercook

ed food

Which pump is likely the source of contaminated water?

A)1B)6C)7D)9

Carriers•Some organisms may transmit diseases without knowing it. If someone has the disease, but doesn’t show any symptoms, they are carriers and can cause someone else to get sick.▫EXAMPLE: When someone gets

measles, they do not show any symptoms for several days. In that time, they can infect others.

Which is the main risk associated with being a disease carrier?

•A) A person may be a carrier of a mild illness.

•B) A person can unknowingly spread the disease to others.

•C) A person may feel guilty for making other people sick.

•D) A person is more difficult to cure if he or she is a carrier.B

Which best describes the danger associated with carriers of an infectious disease?

•A) The carrier may develop symptoms of an infectious disease.

•B) The infectious disease may become resistant to antibiotics.

•C) The infectious disease will mutate into a genetic disease if left untreated.

•D) The carrier may unknowingly transmit an infectious disease to many people.

D

Which carrier would most likely infect the highest number of individuals? •A) a doctor •B) a librarian•C) an engineer•D) a flight attendant

D

Vectors•Vectors are what transfer a disease from one organism to another.▫EXAMPLE: Ticks are vectors because they transfer Lyme disease to humans.

▫EXAMPLE: A human with a cold is a vector because they can cause someone else to get sick.

What most likely spreads diseases such as rabies or Lyme disease? •A) contact with an infectious animal•B) contact with an infectious human•C) breathing contaminated air•D) eating contaminated food

The Anopheles mosquito transmits the parasite Plasmodium to humans. This parasite causes malaria. In this situation, which is the vector of the disease?

•A) Anopheles mosquito •B) Plasmodium•C) human•D) malaria

The bacteria that causes bubonic plague is transmitted to humans by fleas. Which term best describes the role of the fleas in transmitting bubonic plague?

•A) vector•B) carrier•C) parasite•D) pathogen