In syndromic surveillance, all of the above are used in addition to other patterns that suggest an outbreak. Despite the emergence of this innovative surveillance method, most surveillance still depends on tracking reported infections. 

In syndromic surveillance, all of the above are used in addition to other patterns that suggest an outbreak. Despite the emergence of this innovative surveillance method, most surveillance still depends on tracking reported infections. 

In syndromic surveillance, all of the above are used in addition to other patterns that suggest an outbreak. Despite the emergence of this innovative surveillance method, most surveillance still depends on tracking reported infections. 

Scientists predict that rising average temperatures in some regions—a result of climate change—will change the transmission dynamics and geographic range of cholera, malaria, dengue fever, and tick-borne diseases.

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.

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. 

The human papillomavirus (HPV) causes more than 90% of cervical cancer cases.

The human papillomavirus (HPV) causes more than 90% of cervical cancer cases.

Lower respiratory tract infections (including pneumonia) kill more children worldwide than any other infectious disease. Together these diseases are the five leading causes of infectious disease worldwide, accounting for nearly one-fifth of all deaths.

Lower respiratory tract infections (including pneumonia) kill more children worldwide than any other infectious disease. Together these diseases are the five leading causes of infectious disease worldwide, accounting for nearly one-fifth of all deaths.

Lower respiratory tract infections (including pneumonia) kill more children worldwide than any other infectious disease. Together these diseases are the five leading causes of infectious disease worldwide, accounting for nearly one-fifth of all deaths.

Lower respiratory tract infections (including pneumonia) kill more children worldwide than any other infectious disease. Together these diseases are the five leading causes of infectious disease worldwide, accounting for nearly one-fifth of all deaths.

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.

The mosquito is the vector for West Nile virus. The mosquito suffers no ill effects from the virus but transmits it to humans and other warm-blooded creatures (such as crows) when it takes a blood meal. 

The mosquito is the vector for West Nile virus. The mosquito suffers no ill effects from the virus but transmits it to humans and other warm-blooded creatures (such as crows) when it takes a blood meal. 

The mosquito is the vector for West Nile virus. The mosquito suffers no ill effects from the virus but transmits it to humans and other warm-blooded creatures (such as crows) when it takes a blood meal.