When the Software Flashes the Message Something’s Out There
Why We Need Both EPI-X and HAN?
The first hours are critical to the detection, treatment, and control of communicable diseases. The key to success is adequate surveillance systems. CDC maintains and supports two surveillance systems: EPI-X and HAN.
EPI-X
EPI-X is the Epidemic Information Exchange and is a web-based surveillance system. The exchange offers public health professionals a secure system for communicating and sharing preliminary surveillance information. EPI-X provides timely postings about disease outbreaks that have the potential to impact a wide geographical area. Users of EPI-X are notified quickly of breaking health information in an almost real time basis.
EPI-X also includes contributors who may report health events as they occur. EPI-X scientific editorial board members are available 24/7/365 to verify and edit contributions. Most reports are posted within hours of submission and users are notified routinely by daily e-mails and during emergencies via simultaneous email, pager, and telephone communications.
EPI-X utilizes content security technology and is available only to key health officials who agree to respect and honor the security of the system. Each user and contributor must be approved by their state before EPI-X access is granted.
An Example of AN EPI-X Notification from 07/22/2013
A recent example of the value of Epi-X during an emerging public health event is the 2009 H1N1 pandemic. Reports on Epi-X were among the earliest notifications of the H1N1 virus and Epi-X was integral to the ongoing CDC response to this pandemic. On April 6, 2009, Epi-X reported cases of acute respiratory illness in Veracruz, Mexico, an outbreak that was subsequently identified as a novel form of influenza A (H1N1). Through March 15, 2010, over 2,200 reports related to H1N1 were posted on Epi-X.
In addition, Epi-X’s collaboration with CDC’s Division of Global Migration and Quarantine (DGMQ) has resulted in a number of reports that help jurisdictions identify travel-related exposures to disease. These reports are securely transmitted to affected states and provide information to these states on travelers who may have been exposed to communicable diseases during travel. This collaboration with the DGMQ eManifest system allows state public health officials to know who they need to contact in their jurisdictions to perform case identification assessments. The secure nature of the communication is of key importance because the reports contain personally identifiable information to allow for the rapid identification and contact of those travelers.
HAN
HAN stands for Health Alert Network. HAN is CDC’s method for communicating cleared urgent information with federal, state, and local health officials, clinicians, and laboratories. Almost 90% of the population of the US and the eight territories is covered under the umbrella of HAN.
HAN provides three kinds of messages: Health Advisories, Health Updates, and Information Services. A Health Advisory is information on a specific health event and includes recommendations for immediate action. A Health Update provides current information on a specific health events that do not require immediate action. Information Services provide general health information that require no immediate action.
An Example of A HAN Alert
Unlike EPI-X, HAN is not a secure system and allows unlimited access both within and outside the US. Once a subscriber to HAN, you will receive alerts via email when a new HAN alert is distributed.
Do We Need Both
In many ways, EPI-X and HAN are somewhat duplicative. Almost every time there is a HAN alert there is also an EPI-X notification. But, every EPI-X notification is not accompanied by a HAN alert. Why? Remember that EPI-X is preliminary and HAN is cleared information. Preliminary means that it has been vetted by CDC officials but the probable disease outbreak may not be confirmed at the time the EPI-X notification is sent out. Cleared means the disease outbreak or event has been confirmed. This is not a distinction without a difference. Preliminary information received from EPI-X gives state and local health officials a jump start in preparing for and responding to a potential health event. A HAN alert relies on confirmed and cleared information and will sometimes lag several hours behind an EPI-X notification. Without a doubt health officials will receive the correct health information in a timely manner even if they only subscribe to one but not both of these messaging services. The only difference appears to be the faster speed of EPI-X notifications. Feedback from Epi-X users about Epi-X’s role in the response highlighted how crucial Epi-X is both in the early days of an outbreak and during the following, days, weeks, or months of a response. So, if the information is relatively similar, why do we need both systems?
It appears we need both for redundancy in case one or the other fails and for security. If one system is inoperable, it is highly unlikely that the other system will be likewise. It is also important to have at least one secure system (EPI-X) to ensure that preliminary information can be transmitted quickly and with reliability to carefully selected health officials throughout the nation.
Couldn’t EPI-X Provide HAN Alerts?
Probably. But, the cost of merging the systems would be substantial and it would be difficult to render certain components of EPI-X as unsecured while maintaining the strict security of the system. Both seem to work well and serve different purposes. EPI-X is a secure system designed to provide early warning signals to health officials. HAN provides confirmed information to health officials and the general public.
What Can Be Improved
EPI-X and HAN provide early warning alerts to state and local health officials providing critical information that may require immediate action. There remains a lag of several hours between when a problem is diagnosed and reported. This problem can be rectified by standing up robust Health Information Exchanges (HIEs) in at least every metropolitan region in the country. These HIEs will provide true real time reporting of lab reports and emergent disease in a given community. Results are electronically reported to state and local public health authorities and would become triggers for accelerating both EPI-X notifications and HAN Alerts. All together, EPI-X, HAN, and HIEs should ensure that health providers have essential disease information in a timely manner.
