Health emergencies may occur naturally or as the result of intentional actions by a person or persons who wish to harm others. Each health emergency will differ in the population of people affected, the number of people affected, and the type and severity of illness in the affected persons.

Many health emergencies are the result of infectious diseases. Infectious diseases are caused by microbes, including bacteria, viruses, fungi, or protozoa. To cause disease, a microbe must enter a person's body. Though there are multiple pathways for microbes to enter the body, the most frequent routes of microbe entry are through the lungs; ingestion; eyes, nose, or mouth; and contact with injured skin.

Typically, when a microbe enters a person's body, the person's immune system works to fight it off and prevent infection. If the immune system is unsuccessful and the microbe encounters an environment favorable for growth, the person will likely develop an infection.

Types of viral illnesses that may be considered health emergencies include influenza (flu), measles, severe acute respiratory syndrome (SARS), West Nile virus, and an intentional release of smallpox.

Types of bacterial illness that may be considered health emergencies include bacterial meningitis, botulism (caused by a bacterial toxin), and anthrax. Bacterial illness can usually be successfully treated with antibiotics.

Some microbes can be spread from person-to-person while others require direct contact with the primary source.

Other types of health emergencies could be related to non-infectious processes, such as chemicals, radiation, or natural disasters. For more information about health emergencies and emergency response, see the Centers for Disease Control Emergency Preparedness and Response web site.

In the event of a health emergency, the Illinois Department of Public Health and/or local health departments will issue recommendations on treatment for those who are ill, actions to be taken by people who have been exposed but are not ill, and actions people who are unaffected can take to decrease their chance of exposure.

In response to some types of health emergencies, the state and local health departments may distribute medications and/or vaccines to those who have been affected and/or are most at risk. The state and local health departments will disseminate event-specific information through the news media and Web sites.


What to do during a health emergency:

  • Stay calm. Listen to radio and television reports to learn what actions have been recommended.
  • Stay home unless directed to do otherwise by officials.
  • If you need immediate medical attention for a life threatening emergency, call 9-1-1.

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