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Communicable Diseases

Communicable diseases, also known as infectious diseases or transmissible diseases, are illnesses that result from the infection, presence and growth of pathogenic (capable of causing disease) biologic agents in an individual human or other animal host. Infections may range in severity from asymptomatic (without symptoms) to severe and fatal. The term infection does not have the same meaning as infectious disease because some infections do not cause illness in a host.

Health Alert Network (HAN)

The HAN enables public health staff, tribal governments, health care providers, emergency workers, and others to exchange reliable information as outbreaks evolve.

Access the HAN webpage to read messages that have gone out in response to the COVID-19 pandemic and other emerging health issues.

Disease causing biologic agents include viruses, bacteria, fungi, protozoa, multicellular parasites, and aberrant proteins known as prions. Transmission of these biologic agents can occur in a variety of ways, including direct physical contact with an infectious person, consuming contaminated foods or beverages, contact with contaminated body fluids, contact with contaminated inanimate objects, airborne (inhalation), or being bitten by an infected insect or tick. Some disease agents can be transmitted from animals to humans, and some of these agents can be transmitted in more than one way.

Statewide communicable disease surveillance and control activities in Wisconsin are coordinated by the Bureau of Communicable Diseases.

Wisconsin Childhood Communicable Diseases Chart

Last revised May 9, 2023