CDC Health Advisory

Distributed via the CDC Health Alert Network
June 2, 2014, 16:00 (4:00 PM ET)
CDCHAN-00362

Guidance to US Clinicians Regarding New WHO Polio Vaccination Requirements for Travel by Residents of and Long-term Visitors to Countries with Active Polio Transmission

Summary

On 5 May 2014, the Director-General of the World Health Organization (WHO) accepted the recommendations of an Emergency Committee, declaring the international spread of polio to be a public health emergency of international concern (PHEIC) under the authority of the International Health Regulations (IHR) (2005) and issued vaccination requirements for travelers in order to prevent further spread of the disease. IHR is an international agreement among countries to prevent, protect or control the international spread of disease. All countries have agreed to be bound by recommended activities under IHR.

The "temporary recommendations" in response to this PHEIC, the second ever to be issued under IHR, will be reviewed and possibly revised by WHO's Emergency Committee in three months. The burden for enforcement of the polio vaccination requirements under this PHEIC declaration lies with polio-affected countries (termed "polio-infected" by WHO). At this time, the United States government is not expected to implement requirements for entry into the United States.

U.S. clinicians should be aware of possible new vaccination requirements for patients planning travel for greater than four weeks to countries with ongoing poliovirus transmission. The May 5 WHO statement names 10 such countries, three designated as "exporting wild poliovirus" (Cameroon, Pakistan and Syria [Syrian Arab Republic]) that should "ensure" recent (4 to 52 weeks before travel) polio boosters among all departing residents and long-term travelers (of more than 4 weeks), and an additional seven countries "infected with wild poliovirus" (Afghanistan, Equatorial Guinea, Ethiopia, Iraq, Israel, Somalia and Nigeria) that should "encourage" recent polio vaccination boosters among residents and long-term travelers.

At this time, CDC is not aware of what specific steps will be taken by these 10 countries to comply with the PHEIC declaration. U.S. citizens who plan to travel to any of the polio infected countries should have documentation of a polio booster in their yellow International Certificate of Vaccination in order to avoid delays in transit.

Background

Currently 10 countries have active transmission of wild poliovirus (WPV) that could spread to other countries through international travel. From January through April 2014, months normally considered the low-transmission season for polio, the virus already has been carried to three countries: from Pakistan to Afghanistan, from Syria to Iraq, and from Cameroon to Equatorial Guinea. WHO considers this an "extraordinary event" and a public health risk to other countries. If the current spread of WPV continues, cases could multiply considerably as the high-transmission season has already begun. The consequences of further international spread are particularly acute today given that several countries with complex humanitarian emergencies or other major challenges are bordering the infected countries.

Recommendations

Because of the substantial progress of the polio eradication initiative in 2012-2013, and in order to harmonize CDC recommendations with WHO recommendations, CDC now recommends an adult inactivated poliovirus (IPV) booster dose for travelers to countries with active WPV circulation. Countries are considered to have active WPV circulation if they have ongoing endemic circulation, active polio outbreaks, or environmental evidence of active WPV circulation. Travelers working in health care settings, refugee camps, or other humanitarian aid settings in these countries may be at particular risk.

Domestic clinicians should provide the following information to their patients planning international travel to countries experiencing polio outbreaks/active transmission:

  • Travelers to polio-affected areas should receive polio vaccination or a booster polio vaccination prior to travel following the guidance at http://wwwnc.cdc.gov/travel/yellowbook/2014/chapter-3-infectious-diseases-related-to-travel/poliomyelitis.
  • Travelers also may be impacted by new WHO Polio Vaccination Recommendations in countries with ongoing poliovirus transmission:
  • For travel to Pakistan, Cameroon, and Syria (countries exporting WPV)
  • These governments have been asked to ensure that all residents and long-term visitors (of more than 4 weeks) receive an additional dose of oral polio vaccine (OPV) or inactivated poliovirus vaccine (IPV) between 4 weeks and 12 months prior to any international travel and have the dose documented.
  • Residents and long-term visitors who are currently in those countries who must travel with fewer than 4 weeks' notice and have not been vaccinated with OPV or IPV within the previous 4 weeks to 12 months receive a dose at least by the time of departure.
  • These measures should be maintained until at least 6 months have passed without new exportations with documentation that there is strong surveillance for the virus and that people are being vaccinated in all infected and high-risk areas; without such documentation, these measures should be maintained until at least 12 months have passed without new exportations.
  • At this time, CDC has not seen documentation from any of these three countries specifying how these new requirements will be implemented.
    • For travel to Afghanistan, Equatorial Guinea, Ethiopia, Iraq, Israel, Somalia, and Nigeria (In countries that currently have ongoing poliovirus transmission but have not exported WPV to another country in the past 6 months)
    • These governments are encouraged to ensure that residents and long-term visitors receive an additional dose of OPV or IPV 4 weeks to 12 months prior to each international journey; current residents of those countries undertaking travel with fewer than 4 weeks' notice who have not been vaccinated with a dose of OPV or IPV within the previous 4 weeks to 12 months should be encouraged to receive a dose by the time of departure and have the dose documented.
    • These measures should be maintained until at least 6 months have passed without the detection of WPV transmission in the country from any source.
    • At this time, CDC has not seen documentation from any of these seven countries specifying how these new requirements will be implemented.
    • Travelers should also be aware that in the event of new international spread from any one of these seven infected countries, that country would be asked to immediately implement the vaccination requirements for 'States currently exporting wild poliovirus.'
  • Travelers to or from all 10 countries should be given a WHO/IHR International Certificate of Vaccination or Prophylaxis (http://www.who.int/ihr/ports_airports/icvp/en/) to record and serve as proof of their polio vaccination.

Guidance

CDC routinely recommends that anyone planning travel to a polio-affected country be fully vaccinated against polio and that, in addition, adults should receive a one-time booster dose of polio vaccine. Because of the recent PHEIC declaration, anyone staying in any of the polio-affected countries for more than four (4) weeks may be required to have a polio booster shot within the 4 weeks to twelve months prior to departure from that country. This booster should be documented in the yellow International Certificate of Vaccination in order to avoid delays in transit or forced vaccination in country. Either oral poliovirus vaccine (OPV) or inactivated poliovirus vaccine (IPV) may be used for this booster, however only IPV is currently available in the United States.

For more information:

The Centers for Disease Control and Prevention (CDC) protects people's health and safety by preventing and controlling diseases and injuries; enhances health decisions by providing credible information on critical health issues; and promotes healthy living through strong partnerships with local, national, and international organizations.