Updated Recommendations for the Use of Typhoid Vaccine — Advisory Committee on Immunization Practices, United States, 2015

Brendan R. Jackson, MD; Shahed Iqbal, PhD; Barbara Mahon, MD


Morbidity and Mortality Weekly Report. 2015;64(11):305-308. 

In This Article

Precautions and Contraindications

No data have been reported on the use of either typhoid vaccine in pregnant women. In general, live vaccines like Ty21a are contraindicated in pregnancy.[26] Vi polysaccharide vaccine should be given to pregnant women only if clearly needed.[20]

Because Ty21a is a live-attenuated vaccine, antimicrobial agents might interfere with vaccine activity. To be sure the vaccine is fully effective, the vaccine manufacturer advises that Ty21a should not be given until at least 3 days after the last dose of antimicrobial agent and, if possible, antimicrobial agents should not be started within 3 days of the last dose of Ty21a vaccine.[27] A longer interval should be considered for long-acting antimicrobials (e.g., azithromycin). The antimalarial agents mefloquine and chloroquine and the combinations atovaquone/proguanil and pyrimethamine/sulfadoxine can, at doses used for prophylaxis, be administered together with the Ty21a vaccine; however, the manufacturer advises that other antimalarial agents only be administered at least 3 days after the last vaccine dose.[27] Ty21a vaccine can be administered simultaneously or at any interval before or after other live vaccines (injectable or intranasal) or immune globulin if indicated.[26] Ty21a should not be administered to persons during an acute febrile illness or acute gastroenteritis.[21]

Live-attenuated Ty21a vaccine should not be used by immunocompromised persons. The Vi vaccine is theoretically safer for this group. Although the Ty21a strain can be shed in the stool of vaccinees, transmission has not been documented.[21] The Ty21a strain has not been isolated from blood cultures after vaccination.[21] Both the Vi polysaccharide and Ty21a vaccines are contraindicated in patients with a history of hypersensitivity to any component of the vaccine.