The effectiveness of a vaccine against Asian influenza was studied in 1,244 volunteer subjects among the 2,600 men in a prison. Hemagglutination-inhibiting antibodies increased to a maximum within two weeks of vaccination. The titers obtained were highest in the group who received the largest doses of vaccine. Detailed epidemiologic and serologic studies were made during two subsequent waves of epidemic influenza. During the first, vaccines containing 200 and 500 chick cell agglutinating units were about 68% effective, while the vaccine containing 50 CCA units was only about half as effective. During the second wave four months later, all vaccinated men demonstrated nearly equal protection at about the same level observed for the higher doses during the first wave.
Dull HB, Jensen KE, Rakich JH, Cohen A, Henderson DA, Pirkle CI. MONOVALENT ASIAN INFLUENZA VACCINEEVALUATION OF ITS USE DURING TWO WAVES OF EPIDEMIC ASIAN INFLUENZA IN PARTLY IMMUNIZED PENITENTIARY POPULATION. JAMA. 1960;172(12):1223-1229. doi:10.1001/jama.1960.03020120001001