Seroprevalence of measles, mumps, rubella and varicella among staff of a hospital in Riyadh, Saudi Arabia.

This study aimed at screening immune status of Health Care Workers (HCWs) against measles, mumps, rubella, and varicella, and assessing the reliability of the history of previous illness due to these infections or vaccination against them as an indicator of the immune status, as checked by laboratory tests. Demographic data, history of previous illnesses and previous vaccinations were collected using a self-administered questionnaire. Also, serologic screening was done for these infections. Antibodies tested using ELISA. Among tested hospital staff, 71.8%, 60.3%, 47.9% and 68.4% reported history of infection or vaccination against measles, mumps, rubella and varicella respectively, while laboratory results proved that 4.5%, 10.8%, 12.9% and 11.3% were susceptible respectively. Susceptibility was most frequent among housekeeping staff against measles and varicella, while administrative staff were the most susceptibles to mumps, and nurses were the most susceptibles to rubella. Sensitivity of past history of illness as an indicator of the immune status, was found to be (85%, 83%, 66%, 86%); Specificity was (81%, 81%, 89%, 87%); Positive Predictive value (PV) was (99%, 98%, 98%, 98%) and Negative PV was (16%, 29%, 22%, 39%) for measles, mumps, rubella and varicella respectively. Screening for measles, mumps, rubella and varicella among hospital staff is mandatory to detect those who are susceptible for infections and should be vaccinated, and so preventing transmission of these infections to their colleagues or patients.