Not to be inj intravascularly. May not protect all vaccinees; continue personal protection measures against mosquito bites after vaccination. Increased risk of hospitalization for dengue & clinically severe dengue in individuals not previously infected by dengue virus. Not recommended for individuals who have not been previously infected by dengue virus; w/o prior dengue infection, living in non-endemic areas, who travel to endemic areas. Wait until immune function has recovered in patients receiving high doses of systemic corticosteroids given for ≥2 wk. History of serious or severe reactions w/in 48 hr after a prior administration. Syncope; phenylketonuria. Women of childbearing potential should avoid becoming pregnant for 4 wk after vaccination. Not to be administered in individuals <9 yr.