Humoral immunity against pertussis among healthcare workers

Abstract

Background. Vaccination is the most effective way to prevent infectious diseases. Inadequate vaccination coverage among healthcare workers is a major concern for healthcare organizations. The lack of specific immunity against pertussis represents the risk for acquiring a healthcare associated infection by medical staff but also of being a source of infection to patients. More than 70% of all healthcare associated infections are vaccine-preventable. Pertussis remains one of the most important vaccine-preventable infections and continues to be a public health concern even in countries with high vaccination coverage among children. Revaccination of adults against pertussis is not included in the National vaccination schedule of the Russian Federation. Aim. To assess the humoral immunity against pertussis among healthcare workers of the infectious disease hospitals. Materials and methods. We conducted a cross-sectional study that included 252 healthcare workers. All study participants were surveyed and tested for antibodies (immunoglobulins G) against Bordetella pertussis by enzyme immunoassay. Results. The proportion of healthcare workers seronegative for pertussis was 46.8%. The healthcare workers with unknown vaccination status amounted to 40.5%. More than half (55.6%) of the participants have been vaccinated and 3.9% of them have had pertussis in childhood. A recent infection was confirmed in 8.0% of participants who had the level of antibodies to Bordetella pertussis greater than 50 U/ml. The largest proportion of participants seronegative to Bordetella pertussis (55.2%) was observed among those under 30 years. The median level of antibodies against pertussis in seropositive health workers was 28.3 U/ml. Conclusion. The significant proportion of seronegative participants (46.8%) and those who had the recent infection underline the necessity of the improvement of pertussis prevention by implementation of vaccination in the risk groups, including healthcare workers to reduce the risk of healthcare associated infections.