Safety Study of a Human Metapneumovirus Challenge Virus in Healthy Adults

Inclusion Criteria: * General good health, without significant medical illness, physical examination findings, or significant laboratory abnormalities as determined by the investigator * Available for the duration of the trial * Female subjects must agree to use effective birth control methods for the duration of the study Exclusion Criteria: * Pregnant * Currently breastfeeding * Evidence of clinically significant diseases in the nervous system, heart, lungs, liver, autoimmune system, or kidney or involving rheumatism, as determined by medical history, physical examination, or laboratory studies, including urine testing. * Clinically significant alanine aminotransferase (ALT) levels, as determined by the principal investigator (PI) * Behavioral or cognitive impairment or psychiatric disease that, in the opinion of the investigator, affects the ability to understand and cooperate with the study protocol * Human metapneumovirus (HMPV) specific serum immunoglobulin A (IgA) titer greater than 1:50 * HMPV-specific nasal wash IgA titer greater than 1:50 * Positive urine drug toxicology test indicating narcotic use * Medical, occupational, or family problems as a result of alcohol or illicit drug use during the past 12 months * Other condition that, in the opinion of the investigator, would jeopardize the safety or rights of a subject participating in the trial or would render the subject unable to comply with the protocol * History of hypersensitivity reactions * Diagnosis of asthma or reactive airway disease within the past 2 years * Positive result on test for HIV * Positive result on test for hepatitis C virus (HCV) * Positive result on test for hepatitis B virus surface antigen (HBsAg) * Known immunodeficiency syndrome * Use of corticosteroids (excluding topical or nasal preparations) or immunosuppressive drugs within 30 days prior to inoculation * Receipt of a live vaccine within 4 weeks or a killed vaccine within 2 weeks prior to inoculation with challenge virus, rHMPV-SHs * History of a surgical removal of the spleen * Receipt of blood or blood-derived products (including immunoglobulin) within 6 months prior to study inoculation * Current smoker unwilling to stop smoking for the duration of the study * Receipt of another investigational vaccine or drug within 30 days prior to study inoculation * Body mass index (BMI) greater than 35 * Shares household with a child younger than 60 months of age or an immunocompromised individual * Unwillingness to have nasal wash or blood samples saved for future respiratory virus research