Thank you for visiting the CDC web site and for reviewing CDC's Privacy Policy. CDC does not collect any personal information when you visit our web site unless you choose to provide that information. The CDC privacy policy is as follows:

During a visit to the CDC web site, if the web site is simply browsed or information downloaded, certain information will be gathered and stored automatically about the visit. This information does not identify you personally. We automatically collect and store only the following information:

• the Internet domain (for example, "xcompany.com" if a private Internet access account is used, or "schoolname.edu" if connecting from a university's domain) and IP address (an IP address is a number that is automatically assigned to a computer when surfing the Web);

• the operating system and information about the browser used when accessing the site;

• the visit date and time;

• if www.cdc.gov is designated as a home page;

• the pages visited; and

• the address of the web site visited immediately prior to visiting the CDC site.

Collection and analysis of this information in the aggregate will help us enhance site performance, improve informational materials available on our web site, and improve overall customer service. If an e-mail message to CDC is sent or a questionnaire, form, or other online survey found on the CDC web site is completed, CDC will maintain the information in accordance with applicable federal law.

CDC does not disclose, give, sell, or transfer any information about CDC web site visitors unless required for law enforcement or otherwise required by law.

For site security purposes and to ensure that this service remains available to all users, CDC employs software programs to identify unauthorized attempts to upload or change information, or otherwise cause damage.

This site is maintained by the U.S. Government and is protected by various provisions of Title 18, U.S. Code. Violations of Title 18 are subject to criminal prosecution in Federal court.

Use of Cookies

CDC webpages use two types of “cookies” session-based and persistent. The majority of cookies used are session-based. These bits of information are stored temporarily in your computer’s random access memory (RAM) as a line of text. When you close your browser, the cookie is destroyed and no trace of it remains on your hard drive. These session cookies are used solely as a method to improve the user experience for those visiting the site. In very few cases, the CDC web site uses persistent cookies to store information for a longer period. In those cases, the webpage is clearly noted and the user can choose not to use that webpage feature. As noted above, in no case does CDC disclose, give, sell, or transfer any personal information about CDC web site visitors unless required for law enforcement or otherwise required by law.”