Infectious Diseases

Some facts about diseases are listed.

1 may be inherited from a parent

2 may be carried by a vector

3 may be caused by stress

4 may be passed on by contact

5 may enter through the mouth with food

Which numbered statements apply to infectious diseases?

• 2, 4, and 5

• 1, 3, and 5

• 1, 2 and 3

• 2, 3 and 4

Answer explanation

Infectious diseases are disorders caused by organisms — such as bacteria, viruses, fungi or parasites. Many organisms live in and on our bodies. They're normally harmless or even helpful. But under certain conditions, some organisms may cause disease. Some infectious diseases can be passed from person to person directly or mediated by a vector. Some infectious diseases can also be passed on through the mouth with food.

what is the causative agent of Tuberculosis?

• virus

• bacterium

• protoctist

• insect

Answer explanation

Tuberculosis is an infectious disease caused by bacterium called Mycobacterium tuberculosis.

what is the causative agent of Cholera?

• virus

• bacterium

• protoctist

• insect

Answer explanation

Cholera is an infectious disease affecting human digestive system caused by bacterium Vibrio cholerae.

Which row is correct for malaria?

• A

• B

• C

• D

Answer explanation

Malaria is an infectious disease which can be transmitted through the bite of an infected female Anopheles mosquito and these infected mosquitoes carry the Plasmodium parasite which is transmitted to the bloodstream of a person when a mosquito bites.

Which one of the diseases listed below is not an infectious disease...

• malaria

• smallpox

• rabies

• lung cancer

which diseases can be cured by the use of antibiotics?

• cholera and tuberculosis

• HIV/AIDS and smallpox

• smallpox and cholera

• tuberculosis and HIV/AIDS

Answer explanation

antibiotics can only cure infectious diseases caused by bacterium or fungus, never viruses. HIV/AIDS and smallpox are infectious diseases caused by viruses.

Scientists are concerned that avian (bird) flu caused by the H5N1 virus, could infect humans and cause a pandemic. If this occurs, which factors could help prevent humans spreading the disease?

1 killing all poultry

2 reducing all air flights

3 taking a course of antibiotics

• 1 only

• 2 only

• 3 only

• 1, 2 and 3

Answer explanation

Killing all poultry does not prevent the humans spreading the avian flu disease transmission in humans. 

Reducing all air flights will prevent humans from spreading the disease because H5N1 is transmitted through airborne transmission and reducing flights will also reduce the number of people migrating to different places. This can decrease the possibility of humans spreading the virus from place to place.

Taking a course of antibiotics will not help the prevention of virus transmission, because antibiotics can only be used for treating diseases caused by bacteria or fungi, not viruses. Antiviral drugs are used to treat this type of disease instead.

HIV/AIDS can be transmitted through saliva.

• True

• False

Answer explanation

There are no documented cases of HIV being transmitted through spitting as HIV is not transmitted through saliva.

The diagram refers to properties of diseases.

Which area of the diagram refers to properties that are common to both tuberculosis and cholera?

• A

• B

• C

• D

Which disease is least likely to be passed directly from parent to child?

• HIV/AIDS

• Malaria

• Cholera

• Tuberculosis