Emergency department staff and susceptibility to pertussis: A seroprevalence study

Objective: To determine the proportion of ED staff who are susceptible to pertussis. There was evidence that some winter leave in southern Tasmania might be a reason of pertussis infection among unimmunized staff. This results in loss of individual earning and loss of availability of staff during the peak demand periods in the ED. There is evidence in the literature that underdiagnosis and undertreatment of pertussis occurs worldwide. Methods: All ED staff were approached to participate in this seroprevalence study. A self-completed questionnaire was used to record pervious immunization history for pertussis. Blood samples were collected and analysed to detect and quantify immunoglobulin G and immunoglobulin A titres for pertussis. All confidence intervals (CI) are at 95%. Settings: The Royal Hobart Hospital and the co-located Hobart Private Hospital. Results: Ninety-seven of 106 eligible staff took part in the present study, a participation rate of 92% (CI 84-96). Ninety-one of 97 subjects (94%, CI 87-98) believed that they had been immunized for pertussis in childhood; six subjects had either not been immunized or were unsure (6%, CI 2-13). Twenty-three subjects (24%, CI 16-33) had been immunized as adults. There was serologic evidence of recent infection for 21 participants (22%, CI 14-31). Thirty-one participants (32%, CI 23-42) were susceptible to pertussis on the basis of low immunoglobulin G titres. Conclusion: ED staff should routinely be offered booster immunization for pertussis.