Studies with Rhinoviruses in Volunteers: Production of Illness, Effect of Naturally Acquired Antibody, and Demonstration of a Protective Effect Not Associated with Serum Antibody*

The term "rhinovirus" (1-3) is now used to designate a group of immunologically distinct re- spiratory viruses, possessing many properties of enteroviruses but differing by lability in acid media (4-6) and almost exclusive multiplication in the nasopharynx. The first agents isolated that fit this description were the JH and 2060 strains of ECHO 28 isolated by Price (7) and Pelon, Mo- gabgab, Phillips, and Pierce (8) in 1956 and classified by Pelon (9). Modifications in tissue cul- ture technique for isolating these and similar agents, i.e., incubation on a rotating drum and re- duction in pH to 7.0 to 7.3, were introduced by Pelon and Mogabgab (10) and extended by Tyr- rell and associates (4) and Tyrrell and Parsons (5) to include an incubation temperature of 330 C and use of human tissues. Subsequently, many rhinoviruses, reported under a variety of names, have been isolated in association with mild respira- tory illnesses Some of the strains grow only in tissues of human origin (H strains) and some as well in monkey kidney tissue culture (M strains) (3, 5). It has been estimated that rhino- viruses account for 35 to 40%o of the common colds in adults (17).