Neuroticism and antibody responses in military recruits.

Abstract

Problem Research with animals suggests that inoculations given to protect against viruses may be ineffective when given during periods of high stress because stress-related down-regulation of the immune system impairs the immune response to vaccination. Objective This study was undertaken to quantify the effects of stress on antibody production in U.S. Navy recruits. The estimates were developed by comparing the antibody production of stresssusceptible recruits to that of stress-resistant recruits following routine inoculations during the challenging initial phases of training. Approach The 12 highest and 12 lowest scorers on a measure of emotionality and stresssusceptibility were selected from a larger sample. The neutralizing antibody responses to inoculations for adenovirsuses 4 and 7 given the day of arrival at the Recruit Training Command, San Diego, were determined two days after inoculation, then 23-25 days later, then again another 24-27 days later. Results Most recruits had detectable antibody levels two days after inoculation (91.8% for adenovirus 7; 58.4% for adenvirus 4). Among recruits with detectable antibodies two days after inoculation, stress-susceptible recruits had lower antibodies than stress-resistant recruits for both adenoviruses at the time of the first antibody measurement, but not for the two later measurements. Conclusions Antibody responses to booster shots may be sluggish in stress-susceptible individuals if given at a stressful time. This information suggests that it is desirable to allow sufficient time between inoculation and deployment to permit even stress-susceptible individuals to respond to booster shots given as part of preparations for deployment or other instances of potential exposures to important viruses. Additional studies to define the precise time course of antibody responses and determine whether the results generalize to initial inoculations and to other viral and bacterial pathogens would be useful for establishing vaccination policies.