National Center for Emerging and Zoonotic Infectious Diseases

Zoonotic diseases: Approximately 75% of recently emerging infectious diseases affecting humans are diseases of animal origin; approximately 60% of all human pathogens are zoonotic.

Refugee health: An estimated 50,000 to 70,000 refugees are resettled to the United States each year. These individuals can suffer from many health conditions— infectious diseases, malnutrition, and post-traumatic stress disorder caused by war.

Foodborne illness: Food-related diseases affect tens of millions of people and kill thousands and cause more than $9 billion in health care-related costs each year. Preventing a single fatal case of E. coli O157 infection would save an estimated $7 million.

Waterborne illness: Water, the world's most precious commodity, is a primary resource for drinking, recreation, healthcare, industry, and agriculture. Globally, over 900 million people lack access to healthy water; in the United States, there are millions of cases of waterborne illness each year.

Healthcare-associated infections: Nearly 2 million people get infections while in U.S. hospitals each year. Almost 100,000 of them die as a result. The two most common causes are Methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile (C. diff).

Vectorborne diseases: There have been 1.5 million West Nile virus infections since 1999. 2.5 billion people are at risk for dengue in more than 100 endemic countries with 50 million cases of dengue fever each year.

Immunization safety: Monitoring health problems after vaccination is essential to ensure the United States continues to have the safest, most effective vaccine supply in history. CDC's Immunization Safety Office identifies possible vaccine side effects and conducts studies to determine whether a health problem is caused by a specific vaccine.