Infectious diseases

Question 1

What is a disease?

Answer 1

A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism.

Question 2

The difference between an infectious disease and a non-infectious disease

Answer 2

Infectious diseases are transmitted from person-to-person through the transfer of a pathogen such as bacteria, viruses, fungi or parasites. A non-infectious disease cannot be transmitted through a pathogen and is caused by a variety of other circumstantial factors.

Question 3

Name and type of causative organism of cholera

Answer 3

The bacterium Vibrio cholerae.

Question 4

Name and type of causative organism of malaria

Answer 4

The parasite anopheline mosquito.

Question 5

Name and type of causative organism of tuberculosis

Answer 5

The bacterium Mycobacterium tuberculosis.

Question 6

Name and type of causative organism of HIV

Answer 6

The virus Human immunodeficiency virus.

Question 7

Name and type of causative organism of smallpox

Answer 7

The virus variola.

Question 8

Name and type of causative organism of measles

Answer 8

The virus Morbillivirus.

Question 9

How is cholera transmitted?

Answer 9

The cholera bacteria is passed through feces (poop). It is spread by eating or drinking food or water contaminated by the feces (poop) of an infected person.

Question 10

How is malaria transmitted?

Answer 10

Usually, people get malaria by being bitten by an infective female Anopheles mosquito. Only Anopheles mosquitoes can transmit malaria and they must have been infected through a previous blood meal taken from an infected person.

Question 11

How is tuberculosis transmitted?

Answer 11

TB bacteria are spread through the air from one person to another. The TB bacteria are put into the air when a person with TB disease of the lungs or throat coughs, speaks, or sings. People nearby may breathe in these bacteria and become infected.

Question 12

How is HIV transmitted?

Answer 12

You can only get HIV by coming into direct contact with certain body fluids from a person with HIV who has a detectable viral load. These fluids are:

Blood
Semen (cum) and pre-seminal fluid
Rectal fluids
Vaginal fluids
Breast milk.

Question 13

How was smallpox transmitted?

Answer 13

Smallpox spreads from contact with infected persons. Generally, direct and fairly prolonged face-to-face contact is required to spread smallpox from one person to another. Smallpox also can be spread through direct contact with infected bodily fluids or contaminated objects such as bedding or clothing.

Question 14

How is measles transmitted?

Answer 14

Measles is a very contagious viral disease that is spread through the air from person to person. Measles can be transmitted when someone with measles coughs or sneezes, and other people breathing the air containing the measles virus can then get measles.

Question 15

Factors considered in the prevention of cholera

Answer 15

Make sure to drink and use safe water to brush your teeth, wash and prepare food, and make ice.

Question 16

Factors considered in the prevention of malaria

Answer 16

Apply insect repellent to exposed skin. …
Wear long-sleeved clothing and long pants if you are outdoors at night.
Use a mosquito net over the bed if your bedroom is not air-conditioned or screened. …
Spray an insecticide or repellent on clothing, as mosquitoes may bite through thin clothing.

Question 17

Factors considered in the prevention of tuberculosis

Answer 17

Improving ventilation in indoor spaces so there are fewer bacteria in the air.
Using germicidal ultraviolet lamps to kill airborne bacteria in buildings where people at high risk of tuberculosis live or congregate.
Treating latent infection before it becomes active.

Question 18

Factors considered in the prevention of HIV

Answer 18

You can use strategies such as abstinence (not having sex), never sharing needles, and using condoms the right way every time you have sex. You may also be able to take advantage of HIV prevention medicines such as pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP).

Question 19

Factors considered in the prevention of smallpox

Answer 19

Smallpox can be prevented by the smallpox vaccine, also called vaccinia virus vaccine. The vaccine is made from a virus called vaccinia, which is a poxvirus similar to smallpox, but less harmful.

Question 20

Factors considered in the prevention of measles

Answer 20

You can avoid catching measles by having the measles, mumps and rubella (MMR) vaccine. If the MMR vaccine is not suitable for you, a treatment called human normal immunoglobulin (HNIG) can be used if you’re at immediate risk of catching measles.

Question 21

Factors that influence global patterns of distribution of malaria

Answer 21

The three main climatic factors that directly affect malaria transmission are temperature, rainfall and relative humidity (the amount of moisture in the air).

Question 22

Factors that influence global patterns of distribution of TB

Answer 22

Low income countries and deprived areas, within big cities in developed countries, present the highest TB incidences and TB mortality rates. These are the settings where immigration, important social inequalities, HIV infection and drug or alcohol abuse may coexist, all factors strongly associated with TB.

Question 23

Factors that influence global patterns of distribution of HIV

Answer 23

Factors that enhance the spread of HIV transmission include migration, economic instability, social and environmental factors, drug use, increased rates of sexually transmitted diseases (STDs), and poverty. In addition, subgroups of the virus may have different rates of transmission.

Question 24

Importance of of malaria

Answer 24

Malaria is one of the most important public health problems worldwide. It is the leading cause of morbidity and mortality in many developing countries, where young children and pregnant women are most affected. As of 2004, 107 countries and territories have reported malaria transmission.

Question 25

Importance of tuberculosis

Answer 25

Tuberculosis (TB) remains one of today’s global health challenges, ranking as the second leading infectious cause of death and one of the most burden-inflicting diseases in the world.

Question 26

Importance of HIV

Answer 26

HIV is a preventable disease. Effective HIV prevention interventions have been proven to reduce HIV transmission. People who get tested for HIV and learn that they are infected can make significant behavior changes to improve their health and reduce the risk of transmitting HIV to their sex or drug-using partners.

Question 27

How penicillin acts on bacteria

Answer 27

It is an antibiotic that kills bacteria by destroying the cell wall of the microorganism. It does this by inactivating an enzyme necessary for the cross linking of bacterial cell walls.

Question 28

Why do antibiotics not affect viruses?

Answer 28

Viruses don’t have cell walls that can be attacked by antibiotics; instead they are surrounded by a protective protein coat. Unlike bacteria, which attack your body’s cells from the outside, viruses actually move into, live in and make copies of themselves in your body’s cells.

Question 29

How does bacteria become resistant to antibiotics

Answer 29

Bacteria develop resistance mechanisms by using instructions provided by their DNA. Often, resistance genes are found within plasmids, small pieces of DNA that carry genetic instructions from one germ to another. This means that some bacteria can share their DNA and make other germs become resistant.

Question 30

Consequences of antibiotic resistance

Answer 30

Antibiotic resistance leads to higher medical costs, prolonged hospital stays, and increased mortality.

Question 31

Steps to reduce the consequences of antibiotic resistance

Answer 31

There are many ways that drug-resistant infections can be prevented: immunization, safe food preparation, handwashing, and using antibiotics as directed and only when necessary. In addition, preventing infections also prevents the spread of resistant bacteria.