6-3 Diseases & How They Spread

Diseases can be spread in a variety of ways.  Contagious or communicable diseases are diseases that are spread from one person to another, from one animal or plant to another, or from an animal to a person.  If a communicable disease spreads through an entire community or communities it is called an epidemic.

Diseases are spread among humans in a variety of ways.  Shaking hands, sharing drinking glasses or eating utensils, or standing close to each other while speaking, can spread communicable diseases.  Colds and flu can be spread by coughing and sneezing.  AIDS and other diseases are transmitted through direct contact with body fluids, infected blood, or sexual contact.

Antibiotics are drugs that slow the growth of bacteria or kill them without destroying the body's cells.  Penicillin is an antibiotic, which was discovered in 1928.  It is used to treat strep throat, pneumonia, and other bacterial diseases.  Antibiotics are not very helpful in fighting viruses.  Viruses enter cells to attack them and it is difficult to develop drugs that can destroy the virus without also killing the cells.  A vaccination can be given to strengthen the body's immunity against certain viruses and germs.  A vaccine is administered by a shot, or can be taken orally.  A vaccine is made from small amounts of killed or weakened microbes of the disease it causes.  When the killed or weakened germs in the vaccine enter the body, the immune system produces antibodies against the disease-causing germ.  In turn the antibodies multiple and remain in the blood to attach any similar germs that might enter the body in the future.  Vaccines have been developed for measles, mumps, polio, influenza, and others.

Diseases that are not contagious and cannot be spread are called non-communicable diseases.  Smoking can lead to lung disease and even cancer in the lungs and other parts of the body.  The sun's ultraviolet rays have been known to cause skin cancer.  A lack of vitamin C can cause bleeding gums and exhaustion.  Too much fat and cholesterol in the diet, along with a lack of vegetables can lead to heart disease and cancer.  Some non-communicable diseases are passed from parent to child through their genes.  This is known as a hereditary disease.  Hemophilia is an example of this.  It is a disease in which the blood does not clot correctly.

Directions: Answer the questions about diseases and the treatment and prevention of them.

diseases are diseases that are spread from one person to another, from one animal or plant to another, or from and animal to a person.

diseases are not contagious and cannot be spread.

An occurs if a communicable disease spreads through an entire community or communities.

are drugs that slow the growth of bacteria or kill them without destroying the body's cells.

, discovered in 1928 is used to treat strep throat, pneumonia, and other bacterial diseases.

A is used to fight viruses.  It is administered through a shot or orally.

Indicate whether the disease is communicable or non-communicable.  Use C for communicable and NC for non-communicable.

measles

influenza

lung cancer

chicken pox

hemophilia

cystic fibrosis

A disease is passed from parent to child through their genes.

AIDS is transmitted through direct contact with fluids, blood, or contact.