AI is caused by a virus that occurs naturally among birds. Because the virus has the ability to mutate into a form that can efficiently spread among the human population, AI has the potential to cause pandemics. The purpose of this study is to evaluate the safety of and immune response to the AI vaccine H9N2 (6-2) AA ca Reassortant (A/Chicken/Hong Kong/G9/97 x A/Ann Arbor/6/60 ca) in healthy adults who have never been exposed to the H9N2 virus.~This study will last from approximately 6 weeks, up to a maximum of approximately 20 weeks. Participation includes a 10-day minimum hospital stay in an isolation unit of the Bayview Medical Center of Johns Hopkins University. Participants will be admitted to the isolation unit 2 days prior to vaccination. At vaccination, participants will be given one dose of the H9N2 (6-2) AA ca Reassortant (A/Chicken/Hong Kong/G9/97 x A/Ann Arbor/6/60 ca) vaccine in the form of nose drops. Each day for the next 7 days, participants' vital signs will be monitored and nasal washes will be collected to test for the presence of vaccine virus. Participants may be discharged from the hospital after 3 consecutive negative viral cultures, but not before Day 7 after vaccination. Follow-up visits will occur on Days 21, 28, and 42, and will include blood collection and a physical exam.~Participants who received the first dose of the (A/Chicken/Hong Kong/G9/97 x A/Ann Arbor/6/60 ca) vaccine will be asked to receive a second dose of the vaccine 4 to 12 weeks after receiving the initial dose. Study procedures will be identical to those related to the first vaccination.
Avian influenza (AI), also known as bird flu, has become a major public health concern in many regions of the world. The purpose of this study is to evaluate the safety of and immune response to an AI vaccine in healthy adults.