We did not limit the search based on date of publication and included articles written in English and French. In addition to full-text articles, we included articles for which only abstracts were available as long as time, location, and diagnostic method for the occurrence of human typhoid cases were clearly described. We excluded the studies that do not report original occurrence of typhoid fever in humans. For instance, many retrieved articles concern molecular biological characteristics of preexisting isolates (eg, susceptibility to antimicrobials or other medicinal plants) and were therefore excluded. Some studies were excluded because they report the occurrence of a Salmonella infection without providing information about their serotype. Other studies were excluded because they report a survey or an analysis of the existing data, but do not report novel occurrence of typhoid cases. Where there was discordance among the two reviewers, the first author made a determination after discussions.