Medical and nursing students with suboptimal protective immunity against vaccine-preventable diseases

OBJECTIVES: Medical and nursing students (hereafter referred to as "healthcare students") are at risk of contracting and transmitting infectious diseases in a hospital setting. The aim of our study was to evaluate the vaccination history of healthcare students and their serologic immunity against vaccine-preventable diseases.

DESIGN: Prospective cohort study.

SETTING: A tertiary care children's hospital in Athens, Greece, which is affiliated with the University of Athens.

METHODS: Healthcare students were recruited during April through November 2007. The information obtained from these students during personal interviews included demographics and whether there was a history of varicella, measles, mumps, rubella, and/or hepatitis A or B virus infection. Vaccination history and documentation of disease were abstracted from available medical records. Serum antibodies against the above-mentioned viral agents were determined by use of an enzyme-linked immunosorbent assay. Seronegative students and those with immunization gaps were referred to local vaccination clinics, and compliance was assessed 3 months later.

RESULTS: A total of 187 healthcare students were recruited, 131 (70.1%) of whom provided complete documentation of vaccination history. Adequate immunity against diphtheria and tetanus was documented for 55 (37.2%) and 73 (49.3%) of the 148 participants, respectively, whereas age-appropriate vaccination against pertussis, diphtheria, tetanus, and poliomyelitis was noted for 138 (93.2%), 147 (99.3%), 147 (99.3%), and 147 (99.3%) healthcare students, respectively. Of 185 healthcare students, 171 (92.4%) were immune to varicella. Of 182 healthcare students, 179 (98.4%) were immune to measles, 163 (89.6%) were immune to mumps, and 176 (96.7%) were immune to rubella. Of 179 healthcare students, 151 (84.4%) were immune to hepatitis B virus. Of 178 healthcare students, 26 (14.6%) were immune to hepatitis A virus. Antibodies (10 IU/L or higher) to hepatitis B surface antigen were detected for 151 (84.4%) of 179 healthcare students, and antibodies (10 IU/L or higher) to hepatitis A virus were detected for 26 (14.6%) of 178 healthcare students. Fewer than 30% of participants were in full compliance with recommended vaccinations.

CONCLUSIONS: We have determined that there is a certain proportion of healthcare students who are susceptible to certain vaccine-preventable diseases. The development of an appropriate vaccination strategy is required to decrease the risk of transmission in a hospital setting.