The presence of neutralizing antibodies against measles virus in healthy laboratory monkeys 1 and the frequent recovery of a measles-like agent (MINIA, monkey intranuclear inclusion agent) from trypsinized monkey kidney tissue2 raised the following questions. First, how closely are human and monkey measles-virus strains related? Second, has the virus isolated from monkey kidney tissue been derived by contact of the monkey with a human source, or does a simian variety exist which causes a measles-like infection, with or without disease? Third, would such strains derived from monkeys be of value in human vaccination? The answers to these questions require comparative studies of: (1) the biological, physiochemical, and antigenic properties of the 2 viruses; (2) their pathological and epidemiological behavior under natural and experimental conditions; (3) their ability to cross protect.
Biological and Physiochemical Properties
Earlier investigations 3 revealed that measles and MINIA viruses were similar in their tissue culture