COST-EFFECTIVENESS OF PREVACCINATION SCREENING OF HEALTH-CARE WORKERSFOR IMMUNITY TO MEASLES, RUBELLA AND MUMPS

Objectives: To determine the value of infection and vaccination histor ies as predictors of immunity to measles, rubella and mumps, and to co mpare the costs of various screening strategies with the cost of unive rsal vaccination of health care workers. Setting: Staff employed by a Sydney children's hospital. Methods: Histories of measles, rubella and mumps infection or vaccination were compared with the results of sero logical testing to determine which historical statements had high posi tive predictive Values (PPV) for immunity. Using this, we devised thre e prevaccination screening strategies and compared their costs with th e cost of universal staff vaccination. Results: Of 235 participants, 9 8.3% were serologically immune to measles, 96.6% to rubella and 83.0% to mumps. Historical statements indicating immunity with a PPV of more than 95% were histories of measles or of rubella vaccination, and per sonal recollection of mumps infection. Strategies using historical scr eening were cheaper than universal vaccination, which in turn was chea per than using serological screening alone. Conclusions: Among health care workers at occupational measles, rubella and mumps, need for vacc ination can be reduced by combining historical and serological screeni ng. Where screening is felt to impose an administrative burden, a univ ersal vaccination strategy costs 30%-50% more than strategies which us e historical screening.