N. Engl. J. Med. 381, 2209–2218 (2019)

A conjugate vaccine for typhoid is immunogenic in children in a region in which typhoid is endemic.

Typhoid fever is a systemic febrile illness that disproportionately affects children and teenagers and is a major public-health challenge in low- and middle-income countries. Although two vaccines are currently available, vaccination has not been widely implemented due to low immunogenicity and challenges in delivery to young children.

A typhoid conjugate vaccine (TCV) has recently been developed with the intention of improving immunogenicity relative to that of previous vaccines. In a phase 3 trial in Kathmandu, Nepal, where typhoid is a major problem, 20,019 children were randomly assigned to receive TCV or the MenA vaccine. A single dose of the TCV was immunogenic and was effective in reducing Salmonella Typhi bacteremia.