ROUEN, France - Children can infect adults with pertussis, and researchers have demonstrated that adults also serve as potential sources of transmission; they can infect children and other adults within a pediatric emergency care unit.
Nosocomial pertussis among health care workers (HCWs) has been previously described, and studies indicate that health care personnel may be infected with Bordetella pertussis more frequently than indicated by the occurrence of a recognized clinical illness.
In 1997, a 55-year-old nurse in a French pediatric emergency unit who had a respiratory illness and paroxysmal cough for five weeks was diagnosed with pertussis. An epidemiological investigation followed and indicated that other HCWs from the same unit had recent or acute B. pertussis infection.
To avoid further transmission, all HCWs with a cough were treated. A new case of acute pertussis, however, was identified in a 41-year-old from the same unit.
Pertussis is a threat to HCWs in contact with children, and diagnosis should be made on a clinical basis. Therefore, all emergency department staff in contact with HCWs infected with pertussis should be treated, according to a study in Infection Control and Hospital Epidemiology.
Researchers studied a pediatric emergency unit staff by observing 61 HCWs who had contact with all children in the unit and who sometimes performed invasive procedures. The first case occurred in the 55-year-old who had symptoms of cough, post-tussive apnea and vomiting.
Throughout the period she coughed, the nurse continued working and was in constant contact with her staff. Of the 61 staff members, 59 were asked if they had experienced cough within the previous months, and if they responded positively they were examined by a physician.
Staff were also asked if they had been vaccinated against pertussis or had a history of the disease. Serum samples and nasopharyngeal aspirates were also collected from each staff member and analyzed.
Researchers confirmed pertussis in staff members who had unexplained acute coughing illness that lasted at least three weeks, had positive B. pertussis culture from nasopharyngeal swabs and increased antibodies directed against pertussis toxin.
Researchers found that between April and August 1997, 11 children with pertussis were admitted to the unit; four of them had a positive culture for B. pertussis. There were 11 HCWs who had acute cough in the last five months and who had not been furloughed while they were symptomatic.
Erythromycin was given to the 11 HCWs for 14 days, even though their infection had likely diminished, to stop the spread of pertussis. One person had increased antibodies to pertussis toxin and a positive culture for B. pertussis.
Definitive pertussis diagnosis, according to researchers, requires the recovery of the organism fromnasopharyngeal specimens. Attempts to isolate B. pertussis are more likely to be successful when specimens are collected less than 21 days after cough onset.
All HCWs in the unit were treated with spiramycin (Rovamycine, Rhône-Poulenc Rorer) for 10 days, except the case with the positive culture, who was treated for 14 days. Overall, researchers identified 10 cases of pertussis; nine people had a paroxysmal cough and one person had a chronic cough with a positive B. pertussis culture.
What is not clear, according to the study, is whether pertussis was transmitted from patients to HCWs or from HCWs to HCWs. This is because patients with demonstrated pertussis were admitted during the outbreak.
Adults can transmit pertussis to other adults and children. The researchers therefore recommended that all HCWs be given postexposure prophylaxis if they have had close contact with a child who has pertussis.
For more information:
- Gehanno JF, Pestel-Caron M, Nouvellon M, et al. Nosocomial pertussis in healthcare workers from a pediatric emergency unit in France. Infect Control Hosp Epidemiol 1999;20(8):549-552.
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