Answer:
in five (5) years
Explanation:
Typhoid fever is a disease caused by eating or drinking food or water contaminated with a bacteria called Salmonella typhi. Some symptoms of typhoid fever include high fever, abdominal pain, weakness, constipation and mild vomiting. The S. typhi Ty21a (Ty21a) vaccine is a live attenuated vaccine created by reducing the virulence of the pathogen, which is orally administrated. Revaccination with Ty21a is recommended after 5 years in the USA and 7 years in Canada after first vaccination, regardless of the risk of infection. However, the period of protection after Ty21a immunization still has not been well defined.