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close this bookAlternative Techniques - For Teaching about HIV/AIDS in the Classroom (Peace Corps, 1996, 205 p.)
close this folderTransmission games
View the documentWho has the AIDS virus?
View the documentThe spreading of communicable disease
View the documentShaking STD's
View the documentThe AIDS risk game
View the documentAIDS problem situations
View the documentChain of communicable disease game

Chain of communicable disease game

Objective:
· To assist in identifying links in the communicable disease chain that can be broken to prevent and control the spread of some communicable diseases, including AIDS.

Target Group:
· Upper secondary school students, adults

Group Size:
· Six people per group

Materials:
· Link/Characteristics game cards (See Appendix II)

Preparation:
· Duplicate the number of sets of cards equal to the number of groups. Cut the cards apart and keep them in individual sets. Number the reverse of each set of cards from 1 to 30.

Time:
· 20 minutes

Directions:
· Divide participants into groups of six, three players per team.

· Place a set of labeled cards, number side up, on the table top in view of all of the players in the group.

· Explain that this game is similar to the game "concentration". (See Prevent AIDS Concentration rules). The first player selects a card by calling a number. The card with that number is turned over and the player must then make a match between a communicable disease chain link and its corresponding AIDS characteristic.

Example:
Transmission (Link) - Unprotected Sexual Intercourse (AIDS Characteristic)

· Each team should select the order in which team members play. Players can consult with team mates if necessary.

· When all of the cards are matched, the game is over.

· Have a large group discussion on the ways they players think the links in the "Communicable Disease Chain" can be broken to prevent the spread of HIV (or other communicable diseases).

COMMUNICABLE DISEASE CHAIN

To cause disease, the agents of infection must travel from one person to another. This creates a cycle which can be visualized as a chain linking all the necessary components for spreading of disease. Understanding and breaking the chain at any one link can prevent further infection.


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A. The first link in the chain is AGENT.

THE GERM WHICH PRODUCES AN INFECTION. Most germs can be classified as either viruses, bacteria, fungi, or yeast. Like any life form, germs need a certain environment in order to survive. Some germs need air and die without it. Other germs die when exposed to air. Some germs need moisture and will die if their environment is dry. Warmth is a requirement for many germs, while some can survive in extreme cold or heat (even freezing or boiling temperatures). Certain nutrients (foods) are a must for germ growth, although some germs can survive for years with no nutrients while in the spore stage. All germs must eventually reproduce or they will die out. Antibiotics are chemicals which kill germs either by blocking their use of available nutrients (bacteriocidal) or by preventing reproduction (bacteriostatic)

A. The first link in the chain is AGENT.

B. The second link in the chain is RESERVOIR.

The germ reservoir is ANY PLACE GERMS CAN LIVE. Some can live only in humans or animals, while others can survive in inanimate reservoirs such as soil, air, water, food, or any such objects.

B. The second link in the chain is RESERVOIR.

C. The third link in the chain is PLACE OF EXIT.

WHERE THE GERM LEAVES THE RESERVOIR. Some germs leave animal reservoirs (humans, dogs, cats, skunks, etc.) through body openings such as the mouth, nose, rectum, genitals and wounds.

C. The third link in the chain is PLACE OF EXIT.

D. The fourth link in the chain is the METHOD OF TRANSMISSION.

HOW THE GERM TRAVELS FROM THE RESERVOIR'S PLACE OF EXIT TO ITS DESTINATION. A sneeze can send millions of germs into the air inside tiny droplets. The wind can carry some germ spores for miles. Human feces and urine can contaminate soil or water, especially if these wastes are allowed to enter water supplies without proper treatment. Kissing, sexual contact, or any contact with an infected sore can allow some germs to travel from reservoir to the new host.

D. The fourth link in the chain is the METHOD OF TRANSMISSION.

E. The fifth link in the chain is PLACE OF ENTRY.

THE PLACE WHERE THE GERM COMES INTO THE PERSON. Germs enter a new host in many ways. Germs in the air can be breathed in through the mouth or nose; germs in the water or food can enter the mouth and digestive system; and some germs enter through cuts or breaks in the kin. Others enter by direct contact with moist body areas as in most sexual intercourse.

E. The fifth link in the chain is PLACE OF ENTRY.

F. The final link in the chain is the SUSCEPTIBLE HOST.

BEHAVIORS, CONDITIONS, ENVIRONMENTAL AND INHERITED FACTORS WHICH MAKE A PERSON MORE LIKELY TO GET A DISEASE.

The condition of your body can affect its susceptibility, or danger of infection. Even when germs enter the body, infection does not always occur. Some people have already had certain diseases and have built an acquired immunity against future infections from that germ. Others have had innoculations which give the body artificial immunity. A body cannot fight some germs by producing antibodies and some germs are just too fast and tough for the white blood cells to handle. Good physical and mental condition, aided by proper nutrition, help the body resist infection. Proper hygiene, no breaks in the skin, and physical or chemical germ barriers are other defenses which help prevent the germ invasion. IF ANY OF THESE DEFENSES BREAK DOWN, THE HOST IS MORE SUSCEPTIBLE TO INFECTION.

F. The final link in the chain is the SUSCEPTIBLE HOST.

The chain of infection model presents opportunities to prevent infection by applying disease facts in choosing our behavior.

COMMUNICABLE DISEASE CHAIN AIDS NARRATIVE

Human Immunodeficiency Virus (HIV)

AGENT

Human Immunodeficiency Virus (HIV) is known as the virus which causes AIDS. HIV is the most common and appropriate form used. However, there are several names used for this virus:

· HTLV-III - Human T-Lymphotrophic Virus Type III
· LAV - Lymphadenopathy Associated Virus
· AIDS virus

A. Human Immune System B. Asymptomatic carrier

RESERVOIR

A. The immune system is the body's mechanism for defending itself against harmful germs. For most diseases you acquire immunity (the body's resistance to disease) after exposure to a germ (virus, bacteria, fungi or yeast). When a germ enters the body, the immune system produces antibodies. These antibodies attempt to destroy or neutralize the invading organism.

The immune system includes many body organs and tissues. Human blood is also part of the body's immune system which contains different types of white blood cells (T-cells) that help fight infection.

The Human Immunodeficiency Virus attacks a person's immune system through entering specific T-cells and damaging the person's ability to fight other diseases. Without a functioning immune system, the person now becomes vulnerable to becoming infected by opportunistic diseases which may cause life-threatening illness.

Life-threatening illness that ordinarily would never get a foothold. This illness is called an "opportunistic disease" - using opportunity of lowered resistance to infect and destroy.

B. A large number of people who are infected with the AIDS virus have no signs or symptoms. This asymptomatic reservoirs of infected individuals are capable of spreading the infection through risk behaviors.

Penis, Vagina, Contaminated Blood

PLACE OF EXIT

The human immunodeficiency virus is found in several body fluids (semen, vaginal secretions and blood). During sexual contact an infected person's blood or semen and possibly vaginal secretions exit the body through the penis and vagina. The virus also exits the body through contaminated blood.

· on needles and syringes shared by drug users
· through contaminated blood products
· in blood donated for transfusion
· from pregnant women to unborn child

In 1989 a blood screening program was put into place to protect those receiving transfusions from contaminated blood.

Blood, semen, and vaginal secretions

METHOD OF TRANSMISSION

HIV is transmitted by high risk behaviors:

1. Unprotected sexual intercourse (heterosexually or homosexually)
2. By sharing needles and syringes for intravenous drug use
3. Receiving contaminated blood products
4. HIV positive pregnant women to their unborn infants

HIV is not spread through casual contact - sweat, tears, drinking from the same glass, hugging, etc.

Engaging in risk behaviors or deciding to abstain from risk behaviors are personal choices that will determine if you are a person at risk.

Anus, Penis, Vagina, bloodstream, mouth

PLACE OF ENTRY

Although the HIV is found in several body fluids, a person acquires the virus during sexual contact involving an infected person's blood or semen and vaginal secretions. The virus then enters a person's bloodstream through their rectum, vagina, penis, or mouth. Small (unseen by the naked eye) tears in the surface lining of the vagina or rectum may occur during intercourse thus opening an avenue for entrance of the virus directly into the bloodstream.

Anyone engaging in risk behaviors

SUSCEPTIBLE HOST

The human immunodeficiency virus infects persons who expose themselves to known risk behaviors. Risk behaviors are a matter of individual choice. The epidemic is no longer limited to certain risk groups.

AIDS is everyone's concern.

Chain Links

AIDS Characteristics

Agent

HIV

Reservoir

asymptomatic carrier

Reservoir

human immune system

Place of Exit

contaminated blood

Place of Exit

penis

Place of Exit

vagina

Method of Transmission

unprotected sexual intercourse

Method of Transmission

sharing needles

Method of Transmission

infected pregnant woman to unborn child

Method of Transmission

contaminated blood

Place of Entry

penis

Place of Entry

vagina

Place of Entry

anus

Place of Entry

blood

Susceptible Host

anyone engaging in risk behavior


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