Strep throat is a bacterial infection that can be treated with antibiotics. The common cold and influenza are both viral infections, which do not respond to antibiotics. Antivirals may be prescribed instead.

Strep throat is a bacterial infection that can be treated with antibiotics. The common cold and influenza are both viral infections, which do not respond to antibiotics. Antivirals may be prescribed instead.

Strep throat is a bacterial infection that can be treated with antibiotics. The common cold and influenza are both viral infections, which do not respond to antibiotics. Antivirals may be prescribed instead.

White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

White blood cells are not a type of infectious agent. Part of the immune system, white blood cells fight infection rather than cause it. 

“Antibiotic resistance” refers to the ability of bacteria to resist the effects of an antibiotic. Antibiotic resistance occurs when bacteria undergo a genetic change that reduces or eliminates the effectiveness of drugs or other agents designed to cure or prevent infection.

“Antibiotic resistance” refers to the ability of bacteria to resist the effects of an antibiotic. Antibiotic resistance occurs when bacteria undergo a genetic change that reduces or eliminates the effectiveness of drugs or other agents designed to cure or prevent infection.

Each year about 76 million Americans—or one in four—become infected by what they eat. Approximately 325,000 are hospitalized. More than 5,000 (14 a day) die.

Each year about 76 million Americans—or one in four—become infected by what they eat. Approximately 325,000 are hospitalized. More than 5,000 (14 a day) die.

Smallpox cannot be found naturally in the wild. Smallpox was officially declared eradicated from the globe in 1980, after an 11-year WHO vaccination campaign—the first human disease to be eliminated as a naturally spread contagion. Today, the virus remains only in laboratory stockpiles.

Smallpox cannot be found naturally in the wild. Smallpox was officially declared eradicated from the globe in 1980, after an 11-year WHO vaccination campaign—the first human disease to be eliminated as a naturally spread contagion. Today, the virus remains only in laboratory stockpiles.

In 2008, more than 33 million people worldwide were infected with HIV (human immunodeficiency virus). In that same year, an estimated 2 million people died from AIDS (acquired immunodeficiency syndrome), the final stage of HIV infection.

In 2008, more than 33 million people worldwide were infected with HIV (human immunodeficiency virus). In that same year, an estimated 2 million people died from AIDS (acquired immunodeficiency syndrome), the final stage of HIV infection.

The gap in life expectancy between the richest and poorest countries now exceeds 40 years.

The gap in life expectancy between the richest and poorest countries now exceeds 40 years.

The gap in life expectancy between the richest and poorest countries now exceeds 40 years.

Infection occurs when viruses, bacteria, or other microbes enter your body and begin to multiply. Disease follows when the cells in your body are damaged as a result of infection, and signs and symptoms of an illness appear.

About 36,000 people die from flu-related complications each year in the United States. More than 200,000 are hospitalized.

About 36,000 people die from flu-related complications each year in the United States. More than 200,000 are hospitalized.