RT Journal Article SR Electronic T1 Salmonella typhi Vi conjugate vaccine reduced the incidence of typhoid fever in 2 to 5 year old children JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 179 OP 179 DO 10.1136/ebm.6.6.179 VO 6 IS 6 YR 2001 UL http://ebm.bmj.com/content/6/6/179.abstract AB