Healthcare Workers in Bulgaria - Are They Protected From Vaccine-Preventable Infections?

Abstract

Background: Healthcare workers (HCWs) are at increased risk of exposure to many viral infections, including vaccine preventable diseases (VPDs) such as measles, mumps and rubella (MMR) as compared to non-HCWs. Immunity of HCWs against these viruses is mandatory in a healthcare setting due to possible exposure from patients or colleagues. Aim: To provide an assessment of anti-measles, mumps and rubella IgG seropositivity among Bulgarian HCWs employed in hospitals and regional health inspectorates (RHI), as an indicator of protective immunity against MMR in this risk group. Materials and Methods: In the current study, 181 HCWs from Infectious Units in regional hospitals in the country, and HCWs from the RHI, involved in the monitoring and surveillance of MMR cases in Bulgaria were screened. Serum specimens from all participants were tested by a commercial indirect enzyme-linked immunosorbent assay (Anti-Measles, Anti-Mumps, Anti-Rubella IgG EIA-Euroimmun®, Germany) for presence of IgG antibodies against measles, mumps and rubella, as an indicator of protective immunity. Results: The study included 181 HCWs, 25 male and 156 female, aged 22 to 66 years. The average protective seroprevalence for measles, mumps and rubella was 82.9%, 76.2% and 92.3% percent, respectively. The highest share of negative results were obtained for mumps-specific IgG – 23.2% (42/181), followed by measles 16.6% (60/181) and rubella-specific IgG 7.7% (19/181). Regarding the age distribution, the highest number of HCWs non-immune to measles and mumps was found among the 31- 40-year olds, and against mumps – among the 41-50-year-olds. Conclusion: HCWs are at greater risk of contracting infections than the general population because of contact with sick patients or infectious material. Infected healthcare workers can spread nosocomial diseases to vulnerable patients with more severe illness, leading to complications and even death. Therefore, the vaccination status of HCWs must be strictly monitored.