RSV Challenge in Healthy Adults

Inclusion Criteria:

Healthy adults ages 21 to 40 years. Able to and has given informed consent to participate. Negative urine pregnancy test, if female. Pre-challenge serum neutralizing titer to RSV A2 by microneutalization (MNA) of </= 1:657 (9.36 log2) Non-smoker No significant health abnormalities detected by evaluation of medical history, general physical examination, vital signs and laboratory tests.

Willingness to remain in isolation for 11 nights and comply with all study requirements.

Willingness to remain in the Rochester area for the 28 days of the study.

Exclusion Criteria:

Volunteers with any of the following conditions will not be eligible to participate:

Chronic medical conditions requiring medical followup within the last 6 months. Serologic evidence of infection with HIV or hepatitis C virus, or presence of hepatitis B surface antigen in serum.

History of medically documented asthma requiring treatment (including over-the-counter medications) at any time.

Any abnormal laboratory results which would render challenge with RSV unsafe or interfere with the interpretation of the subject's response to challenge, e.g., AST, ALT, Bilirubin, BUN, creatinine. ( see Appendix II) Individuals requiring concurrent therapy with medications likely to interfere with evaluation of the response to infection, e.g. antipyretics, anti-inflammatory medications Close contact with children aged less than 2 years, with any individuals with significant immunosuppression, or with individuals greater than 65 years of age.

Health care workers with any patient contact during the two weeks following challenge Pregnancy or uncertain status regarding pregnancy Acute respiratory infection or fever within 1 week of challenge Previous enrollment in a study evaluating RSV challenge viruses or RSV vaccines.

Known glucose intolerance (history of abnormal glucose tolerance test or medical history of diabetes mellitus).

History of chronic obstructive disease, emphysema or other serious or evolving pulmonary disease.

Any condition in the opinion of the investigator might interfere with study objectives or pose excessive risks to subjects.

History of previous hospitalization for a pulmonary condition (ie. Pneumonia, asthma, spontaneous pneumothorax, or severe sinus disease requiring a surgical procedure.

History of frequent serious bacterial infections associated with low white blood cell count (below 4,000 per microgram)