Disease patterns and vaccine-response studies in isolated Micronesian populations.

Abstract

Since 1961 we have had under surveillance the populations of several unusually isolated Micronesian islands in the western Pacific Ocean. The discovery of susceptibility to measles in persons under the age of 25 years led to an immunization program carried out in 1963, which has yielded information on vaccine reactions, safety of the fetus in immunized pregnant women, and characterization of the immune response in a population free from naturally circulating measles virus for the past 5 years. Discovery of similar susceptibility to influenza led to a further series of immunizations with monovalent type A and B vaccines. A subsequent epidemic of type B influenza occurring on an atoll where there had earlier been an epidemic of type A2 influenza provided the remarkable opportunity to compare human primary response following vaccination or natural infection with either type A or B influenza virus, and to evaluate the protective effects of type B vaccine. More recently, we have studied epidemics of rubella, hepatitis, and mumps that have occurred on some islands and demonstrated that other islands remain susceptible to these agents, as well as to parainfluenza and certain adenoviruses. Additionally, the geographical isolation, small land areas, and limited fauna of these islands provide opportunities for investigation of distinct patterns of helminthic, protozoan, and arbovirus infections.