Center for Disease Control and Prevention’s Yellow Book: What is new in 2018?

Morgan Stoa, PharmD, Community University Health Care Center

Every two years, the Centers for Disease Control and Prevention (CDC) updates the CDC Health for International Travel, commonly called the Yellow Book. It serves as a reference for health professionals providing care to international travelers. The 2018 update, recently released online and in print, provides updates on travel vaccinations, antibiotic recommendations for traveler’s diarrhea, special consideration for unique types of travel, and the latest information about emerging infectious disease threats such as Zika, Ebola, and Middle Eastern respiratory syndrome (MERS).

The oral cholera vaccine (Vaxchora®) is now recommended to be given to adult travelers age 18-64 who are traveling to an area of active cholera transmission. Vaxchora® is a live oral vaccine, and has not been studied in immunocompromised patients. Patients also on antimalarial prophylaxis with chloroquine should start taking chloroquine 10 days after the administration of Vaxchora® due to decreased response to the vaccine if chloroquine is started sooner than 10 days after Vaxchora® administration. Antibiotics may also decrease the immune response to Vaxchora®, so the vaccine should not be given to patients who have received antibiotics in the previous 14 days. Vaxchora® may be shed in the stool for at least seven days, and the vaccine strain may be transmitted to unvaccinated close contacts. Clinicians and travelers should use caution when considering whether to use the vaccine in people with immunocompromised close contacts.

Recommendations for traveler’s diarrhea and antibiotic use were also updated. Prophylactic antibiotics should not be recommended for most travelers. The CDC does state, however, that prophylactic antibiotics can be considered in patients who are high-risk hosts, such as those who are immunosuppressed or who are taking critical trips (such as engaging in a sporting event) without the opportunity for time off in the event of sickness. This recommendation was updated due to increasing evidence of resistance of bacterial pathogens to prophylactic antibiotics and association with allergic and adverse reactions.

Several different categories of travel were updated to provide more specific guidance to travelers. Specifically, the section on “Traveling with Infants and Children” saw significant updates around cooking food and safe consumption of various food groups during travel. Emerging diseases like Zika, Ebola, and MERS also saw significant updates as evidence is becoming available regarding threats. Finally, additional travel destination specific recommendations for Cuba and Burma were added in the 2018 update.


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  2. “CDC’S 2018 ‘Yellow Book’ offers food safety advice for travelers”. Food Safety News. 14 June 2017. Accessed 31 Jan 2018.

  3. “New 2018 Yellow Book Available” Centers for Disease Control and Prevention. 26 June 2017. Accessed 31 Jan 2018.

  4. Vaxchora [package insert]. Redwood City, CA: PaxVax, Inc; 2017. Accessed Feb 1 2018

  5. Weinberg, N, et al. “Traveling Safety with Infants & Children”. Centers for Disease Control and Prevention. 31 May 2017. Accessed 31 Jan 2018.

  6. Wong, KK, et al. “Cholera”. Centers for Disease Control and Prevention. 31 May 2017. Accessed 31 Jan 2018.