CDC Cookie Policy

When you visit a page on, the internet browser on your computer may store a small piece of data sent from web servers (commonly called a “cookie”). The “cookie” allows the server to “remember” specific information about your visit while you are using the site and is sent by the browser to servers in all web requests to CDC. The “cookie” also makes it easier for you to use the dynamic features of web pages since they can be used to save certain settings and preferences. Cookies from CDC web pages only collect information about your browser’s visit to our site; they do not collect personal information about you and they are not sent to any other web sites. To learn how to manage or refuse cookies from or any other site see USA.govexternal icon. Cookies uses the following cookies (defined and organized per the Office of Management and Budget’s “Guidance for Online Use of Web Measurement and Customization Technologies” (OMB M-10-22 pdf icon[102 KB, 9 pages]external icon) :

Single-session cookies are used for technical purposes, such as enabling better navigation through the site, facilitating the use of user accounts, and generating aggregated statistics about how the website is used. Single-session cookies may use a unique identifier, but do not publicly expose personal information.
Under the framework of OMB M-10-22, this qualifies as a Tier 1 use. pdf icon[102 KB, 9 pages]external icon

Multi-session or persistent cookies are used to recognize a browser session that was used in a previous visit to a web site, which can improve a user’s experience, for example, by continuing preference settings from previous visits.  These persistent cookies also provide the ability for CDC to gather information on unique visitors to web sites.
Under the framework of OMB M-10-22, this qualifies as a Tier 2 use. pdf icon[102 KB, 9 pages]external icon

The CDC uses a third-party analytics provider (for current provider please see current third-party tools/pages list) to analyze the collected data. The third-party analytics provider does not receive personally identifiable information through these cookies.

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Third-Party Cookies

Some pages on may include web content or functionality from third parties. These third parties may use web measurement and customization technologies (such as cookies) in conjunction with the provision of this content or functionality. You should consult the privacy policies of these third parties for further information. We do not knowingly use third-party tools that place a multi-session cookie prior to the user interacting with the tool unless identified on 3rd party tools site, for example by playing an embedded video. If you become aware of a third-party tool on that places a multi-session cookie prior to any user interaction, please contact Privacy Office (see Contact information here).

Another form of website measurement and customization technology is the use of “flash cookies” which are created by Adobe Flash, a technology that powers web content such as videos. To manage these, visit the Website Storage Settings Panel on Adobe.comexternal icon. does not currently use first-party flash cookies, but they may be used by embedded third-party technologies.

Cookies for Email Subscribers

In order to improve email subscribers’ experience and the overall quality of email subscription services, 3rd party email subscription service provider may use cookies to measure the effectiveness of our email communications and to better tailor email content. Please refer to the third-party tools list and their privacy policy for more information.

Because this links cookie data with an individual user, this would qualify as a Tier 3 use under the framework of OMB M-10-22 pdf icon[102 KB, 9 pages]external icon. We would therefore only connect cookie data to individual users who have consented and opted in to receiving emails.

For data captured in this manner, we would restrict access to individual-level information to employees, contractors, and vendors subject to non-disclosure requirements who require access to this information in order to perform their official duties and exercise controls to limit what data they can view based on the specific needs of their position.

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How to Manage Cookies

Visitors can control aspects of website measurement and customization technologies used on and still have access to comparable information and services on

You can choose not to accept cookies from any website, including, by changing the settings of your browser. You can also delete cookies stored in your browser at any time.

Please use this opt-out instructionsexternal icon to get more information about cookies, including how to delete them from your computer and configure your browser to refuse them from or any other site.

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Page last reviewed: December 12, 2019