This study will enroll healthy adults with no history of previous infection with a dengue virus or a flavivirus. Participants will be randomly assigned to receive a single injection of TV005 or placebo at study entry (Day 0). All participants will receive a single injection of rDEN2∆30-7169 on Day 180. For at least 30 minutes after each vaccination, participants will remain in the study clinic to be monitored for any adverse effects of the vaccines. Participants will record their temperature three times a day for 16 days after the first and second vaccinations.