Vaccine one of the vaccine components is more robust than the others and suppresses the growth and immune response to the other components. This phenomenon was first noted in the trivalent Sabin polio vaccine, where the amount of serotype 2 virus in the vaccine had to be reduced to stop it from interfering with the "take" of the serotype 1 and 3 viruses in the vaccine. This phenomenon has also been found to be a problem with the dengue vaccines currently being researched, where the DEN-3 serotype was found to predominate and suppress the response to DEN-1, −2 and −4 serotypes.
Albert Sabin in the U.S. Army Medical Corps and helped develop a vaccine against Japanese encephalitis. Maintaining his association with Children's Hospital, by 1946, he had also become the head of Pediatric Research at the University of Cincinnati. At Cincinnati's Children's Hospital, Sabin supervised the fellowship of Robert M. Chanock, whom he called his "star scientific son." Sabin went on a fact-finding trip to Cuba in 1967 to discuss with Cuban officials the possibility of establishing a collaborative relationship between the United States and Cuba through their respective national academies of sciences, in spite of the fact that the two countries did