Concentrated Inactivated Measles-Virus Vaccine

Abstract

Introduction In this report we shall describe the preparation and certain properties of concentrated, inactivated measles vaccines produced from monkey kidney tissue cultures. That they can stimulate the production of neutralizing antibodies in a significant proportion of measles-susceptible children if the concentration of killed antigen is adequate has been demonstrated recently, and the results appear in other reports of this Conference.1 Evidence is also at hand which suggests that as little as 1 or 2 doses of such vaccine may substantially reduce the severity of the natural illness in children.2 The demonstration that such vaccinated children, even with a minimal antibody response, are immune to a subsequent challenge with live, attenuated (Enders) vaccine 2 justifies description of the vaccine at this time. Methods Virus Strain. —The Edmonston strain of measles virus in human amnion cell culture, kindly provided by Dr. John Enders, was used throughout. It was further propagated in our