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Epidemic Information Exchange (Epi-X)

Images of different items associated with Epi-X including disease-causing pathogens viewed under a microscope, a laptop computer, a globe, and a mosquito which can carry diseases.

What is Epi-X?

CDC’s Epidemic Information Exchange (Epi-X) is a secure, web-based network that serves as a powerful information exchange. It connects public health professionals involved in identifying, investigating, and responding to public health threats. It provides rapid reporting, immediate notification, editorial support, and coordination between public health professionals during public health investigations.

Who participates in Epi-X?

CDC, state, and local health departments; poison control centers; federal agencies; and other public health organizations participate in Epi-X. Currently, Epi-X has approximately 6000 users.

What is being shared on Epi-X?

Epi-X users submit reports to Epi-X about disease outbreaks, novel diseases, outbreaks in unusual populations, and potential public health events that could affect multiple jurisdictions. Since its inception in December 2000, health officials have posted over 60,000 reports. Some highlights of events reported on Epi-X include:

  • the 2002 West Nile Virus outbreak
  • the 2006 Fusarium keratitis outbreak
  • the 2009 H1N1 influenza outbreak
  • the 2014 Ebola outbreak
  • the 2016 Zika Virus outbreak
  • unknown illnesses in children
  • travelers with contagious illnesses

When do officials exchange information on Epi-X?

Epi-X provides rapid communication whenever there is a public health need. Epi-X editorial staff are available 24 hours a day, 7 days a week to provide help editing and posting reports on the secure website. Epi-X notifies users by immediate email for routine public health events and by telephone and email for emergency reports. Users who contribute reports to Epi-X can request posting within 24 or 48 hours (sooner for emergency reports); most reports are posted within two hours of submission. Users can begin posting comments and having discussions about a report as soon as it is posted.

Why and how is Epi-X “secure”

Access to Epi-X is limited to designated public health officials who need to exchange preliminary (not yet confirmed) information in a secure environment. Epi-X uses the latest encryption and security technology. Safely exchanging preliminary information aids nationwide disease tracking, investigation, and response as soon as officials detect a disease outbreak.

The information exchanged on Epi-X helps health officials coordinate a response and determine next steps to address public health threats. Once officials confirm the information and determine next steps, they can communicate with the public through other communication sources.

Why is information exchanged on Epi-X?

Safely exchanging preliminary information aids nationwide disease tracking, investigation, and response as soon as officials detect a disease outbreak. Epi-X was created to provide public health officials with a single source of up-to-the-minute alerts, reports, discussions, and comments — contributed by their peers, and moderated by Epi-X staff at CDC. The network’s primary goal is to inform health officials about important public health events, to help them respond to public health emergencies, and to encourage professional growth and exchange of information.

How can I become an Epi-X user?

Each potential user must obtain pre-approval from their organization before enrolling in Epi-X. The authorizing official at each participating organization designates the public health officials who can enroll as Epi-X users. For users at the state level, this authorizing official is the state epidemiologist. Public health professionals interested in participating in the program can contact Epi-X at

Epi-X allows users to communicate timely, provisional information about infectious disease outbreaks and other public health events in a secure environment.

A laboratory worker writes information on a petri dish with a culture growing in it.

On 3/10/2006, New Jersey health officials reported three cases of Fusarium keratitis on Epi-X and requested information on similar cases nationwide. Largely because of this posting, 109 cases were identified in multiple states by early April. On 4/9, an MMWR Dispatch was posted on Epi-X that described the outbreak and a possible link to a contact lens solution. On 5/15, the implicated product was recalled and cases dramatically declined.

Health workers screen passengers for signs of ill health before they board an airplane.

During CDC’s Ebola outbreak activation, Epi-X was instrumental in the domestic response efforts. The Division of Global Migration and Quarantine coordinated with Epi-X to distribute interstate movement notifications for persons under monitoring for Ebola. During the response, 26,526 interstate movement notifications were distributed via Epi-X to state and local health departments. Additionally, the secure and bi-directional functionality of Epi-X provided an ideal platform for other divisions within CDC to distribute guidance documents to various public health entities.