HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Warren, J. Articles by Rasmussen, A. F. Search for Related Content PubMed Articles by Warren, J. Articles by Rasmussen, A. F.

The Antibody Response in Human Beings Inoculated with Japanese Encephalitis¹ Vaccine, Chick Embryo Type^,2

From the Department of Virus and Rickettsial Diseases, Army Medical Department Research and Graduate School, Army Medical Center, Washington 12, D. C.

Abstract

1. Japanese encephalitis vaccines which were prepared from infected mouse-brain or chick-embryo tissue, and were of adequate potency as measured by the standard mouse-protective test, were found to be equally effective in immunizing human beings when the vaccines were administered to soldiers in two doses of 2.0 ml each given four days apart. Approximately 30 per cent of the men developed neutralizing antibodies following immunizations with either vaccine.

2. Human beings immunized with 3.0 ml of chick embryo vaccine given subcutaneously in doses of 1.0 ml on the first, seventh, and thirtieth day developed neutralizing antibody with twice the frequency obtained with the first schedule.
Similar results were obtained in a small group of persons who received three intracutaneous injections of 0.1 ml each of vaccine over a period of a month.

3. A recall dose of vaccine administered subcutaneously to eight persons one year after vaccination elicited a significant rise in neutralizing antibody in five cases.
A recall dose of 0.1 ml injected intradermally into another group of eight previously vaccinated persons resulted in a marked rise in the serum neutralization index of all eight.

4. Neutralizing antibodies which appeared following primary vaccination persisted for a year in six of fourteen individuals.

5. Only one of the human volunteers receiving either vaccine by either schedule developed specific complement-fixing antibodies to Japanese encephalitis virus following primary vaccination. However, an appreciable number of soldiers had antibodies which reacted with antigen prepared from normal chick embryo. Complement-fixing antibodies to Japanese encephalitis virus appeared in low titer in the sera of about one third of the persons who were repeatedly vaccinated.

Footnotes

¹ Concerning the use of the term "Japanese B Encephalitis" we feel that the perpetuation of the "B" in this descriptive name is superfluous. The use of the term Japanese "B" implies the existence of type "A" encephalitis (encephalitis lethargica) which has been of little importance in Japan in recent years. The original separation of Japanese encephalitis into two clinical types, "A" and "B", was done by Kaneko and Aoki in 1928 before anything was known regarding the viral etiology of acute epidemic encephalitis. Because the use of the letter "B" is highly confusing to the uninitiated, it is our belief that writers should drop the use of this archaic terminology.

² Presented at the meeting of the Society of American Bacteriologists, Philadelphia. Pennsylvania, 15 May 1947.