Seroprevalência de Bordetella pertussis em profissionais de saúde num hospital português

Introduction: Bordetella pertussis causes an acute respiratory infectious disease that, in newborns and infants, can present with severe clinical manifestations or even death. In Portugal, whole cell pertussis vaccine introduced in 1965 was replaced, in 2006, by the acellular form. An increasing number of cases has been observed, with an incidence of 5.5 per 100,000 cases in 2016. The duration of protection against pertussis is unknown after the last immunization or disease itself. Healthcare staff working with children can be the source of infection of hospital outbreaks and, therefore, knowing the seroprevalence of pertussis among them can help to decide the potential need for vaccination in susceptible professionals. Methods: Prospective study including healthcare workers from neonatology and paediatric departments as well as the clinical pathology laboratory of a Portuguese hospital. People with acute respiratory symptoms, pregnant or vaccinated against pertussis in 2016 were excluded. The seroprevalence for pertussis was tested through immunoglobulin G for pertussis toxin by enzyme-linked immunosorbent assay. Results: The population tested was negative for immunoglobulin G pertussis toxin in 97.8% (88/90); only the remaining 2.2% (2/90) showed equivocal results. Discussion: This population is potentially susceptible to pertussis infection and could be a reservoir for disease and for its transmission. A booster immunisation could be recommended to these individuals.