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CDC Health Information for International Travel 2008

Travel Notices

Current Notices

There are no Travel Health Warnings or Travel Health Precautions currently in effect.

Outbreaks:

In the News:

Travel Notice Definitions

CDC issues different types of notices for international travelers. As of May 20, 2004, these definitions have been refined to make the announcements more easily understood by travelers, health-care providers, and the general public. The definitions are laid out below. They describe both levels of risk for the traveler and recommended preventive measures to take at each level of risk.

Type of Notice/ Level of Concern Scope* Risk for Travelers† Preventive Measures Example of Notice Example of Recommended Measures
In the News Reports of sporadic cases No increased risk over baseline for travelers observing standard recommendations Keeping travelers informed and reinforcing standard prevention recommendations< Report of cases of dengue in Mexico, 2001 Reinforced standard recommendations for protection against insect bites
Outbreak Notice
Outbreak in limited geographic area or setting
Increased but definable and limited to specific settings Reminders about standard and enhanced recommendations for the region Outbreak of yellow fever in a state in Brazil in 2003 Reinforced enhanced recommendations, such as vaccination
Travel Health Precaution Outbreak of greater scope affecting a larger geographic area Increased in some settings, along with risk for spread to other areas Specific precautions to reduce risk during the stay, and what to do before and after travel‡ Outbreak of avian influenza among poultry and humans in several countries in Southeast Asia in early 2004 Recommended specific precautions including avoiding areas with live poultry, such as live animal markets and poultry farms; ensuring poultry and eggs are thoroughly cooked; monitoring health
Travel Health Warning Evidence that outbreak is expanding outside the area or populations initially affected Increased because of evidence of transmission outside defined settings and/or inadequate containment measures In addition to the specific precautions cited above, postpone nonessential travel‡ SARS outbreak in Asia in 2003 Recommended travelers to postpone nonessential travel because of level of risk

*The term “scope” incorporates the size, magnitude, and rapidity of spread of an outbreak.

†Risk for travelers is dependent on patterns of transmission, as well as severity of illness.

‡Preventive measures other than the standard advice for the region may be recommended depending on the circumstances (e.g., travelers may be requested to monitor their health for a certain period after their return, or arriving passengers may be screened at ports of entry).

Travel Notices: Interim Definitions and Criteria

As of May 20, 2004

A. Rationale

CDC issues different types of notices for international travelers. We are refining these definitions to make the announcements more easily understood by travelers, health-care providers, and the general public. In addition, defining and describing levels of risk for the traveler will clarify the need for the recommended preventive measures. From the public health perspective, scalable definitions will enhance the usefulness of the travel notices, enabling them to be tailored readily in response to events and circumstances.

1. In the News: notification by CDC of an occurrence of a disease of public health significance affecting a traveler or travel destination. The purpose is to provide information to travelers, Americans living abroad, and their health-care providers about the disease. The risk for disease exposure is not thought to be increased beyond the usual baseline risk for that area, and only standard guidelines are recommended.

2. Outbreak Notice: notification by CDC that an outbreak of a disease is occurring in a limited geographic area or setting. The purpose of an outbreak notice is to provide accurate information to travelers and resident expatriates about the status of the outbreak and to remind travelers about the standard or enhanced travel recommendations for the area. Because of the limited nature of the outbreak, the risk for disease exposure is thought to be increased but defined and limited to specific settings.

3. Travel Health Precaution: CDC does NOT recommend against travel to the area. A travel health precaution is notification by CDC that a disease outbreak of greater scope is occurring in a more widespread geographic area. The purpose of a travel health precaution is to provide accurate information to travelers and Americans living abroad about the status of the outbreak (e.g., magnitude, scope, and rapidity of spread), specific precautions to reduce their risk for infection, and what to do if they become ill while in the area. The risk for the individual traveler is thought to be increased in defined settings or associated with specific risk factors (e.g., transmission in a health-care or hospital setting where ill patients are being cared for).

4. Travel Health Warning: CDC recommends against nonessential travel to the area. A travel health warning is a notification by CDC that a widespread, serious outbreak of a disease of public health concern is expanding outside the area or populations that were initially affected. The purpose of a travel health warning is to provide accurate information to travelers and Americans living abroad about the status of the outbreak (e.g., its scope, magnitude, and rapidity of spread), how they can reduce their risk for infection, and what to do if they should become ill while in the area. The warning also serves to reduce the volume of traffic to the affected areas, which in turn can reduce the risk of spreading the disease to previously unaffected sites. CDC recommends against nonessential travel to the area because the risk for the traveler is considered to be high (i.e., the risk is increased because of evidence of transmission outside defined settings and/or inadequate containment). Additional preventive measures may be recommended, depending on the circumstances (e.g., travelers may be requested to monitor their health for a certain period after their return; arriving passengers may be screened at ports of entry).

B. Criteria for Instituting Travel Notices

Disease transmission: The modes of transmission and patterns of spread, as well as the magnitude and scope of the outbreak in the area, will affect the decision for the appropriate level of notice. Criteria include the presence or absence of transmission outside defined settings, as well as evidence that cases have spread to other areas.

Containment measures: The presence or absence of acceptable outbreak control measures in the affected area can influence the decision for what level of notice to issue. Areas where the disease is occurring that are considered to have poor or no containment measures in place have the potential for a higher risk of transmission to exposed persons and spread to other areas.

Quality of surveillance: Criteria include whether health authorities in the area have the ability to accurately detect and report cases and conduct appropriate contact tracing of exposed persons. Areas where the disease is occurring that are considered to have poor surveillance systems may have the potential for a higher risk of transmission.

Quality and accessibility of medical care: Areas where the disease is occurring that are considered to have inadequate medical services and infection control procedures in place, as well as remote locations without access to medical evacuation, present a higher level of risk for the traveler or Americans living abroad.

C. Criteria for Downgrading or Removing Notices.

To downgrade a travel health warning to a travel health precaution, there should be—

  • Adequate and regularly updated reports of surveillance data from the area
  • No evidence of ongoing transmission outside defined settings for two incubation periods after the date of onset of symptoms for the last case, as reported by public health officials.

To remove a travel precaution, there should be—

  • Adequate and regularly updated reports of surveillance data from the area
  • No evidence of new cases for three incubation periods after the date of onset of symptoms for the last case, as reported by public health authorities.
  • Limited or no recent instances of exported cases from the area; this criterion excludes intentional or planned evacuations.

In the News and Outbreak Notices will be revisited at regular intervals and will be removed when no longer relevant or when the outbreak has resolved.

  • Page last updated: January 09, 2009
  • Content source:
    Division of Global Migration and Quarantine
    National Center for Preparedness, Detection, and Control of Infectious Diseases
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