Seroprevalence of Pertussis in Healthcare Workers without Adult Pertussis Vaccine Use at a University Hospital in Korea

BACKGROUND

Pertussis is highly contagious respiratory disease. Healthcare workers (HCWs) can be an important mediator of the disease. A seroprevalence of pertussis was investigated in HCWs to determine the immune status against pertussis and to detect the unidentified pertussis.

METHODS

This study was conducted for HCWs at a hospital located in Korea in 2011. After obtaining written informed consent for HCWs voluntarily participating in the study, 10 mL of blood was collected from each subject. Demographic and medical data were collected using questionnaire. Data on the underlying disease and vaccination history were reviewed again through medical records. The presence of anti-pertussis toxin (anti-PT) immunoglobulin G (IgG), and immunoglobulin A (IgA) was detected by quantitative analysis using a commercially available ELISA kit (EUROIMMUN, Lübeck, Germany).

RESULTS

A total of 412 HCW participated in the study. Among them, 14 were excluded due to the inadequate sample amount or medical history not secured. Of the 398 HCWs analyzed, 16.6% (66/398) were men and the mean age was 33.82 ± 9.10 years (range, 21-67). The mean anti-PT IgG titer was 8.32 ± 20.40 IU/mL (range, 0.4-287.5 IU/mL). The overall seroprevalence (rate of anti-PT IgG antibody [Ab] titer > 5 IU/mL) was 33.7%. Three (0.8%) HCWs had the Ab level > 100 IU/mL indicated acute infection. There was no statistically significant difference in the seroprevalence and mean titer of anti-PT IgG Ab according to age group, type of occupation, patient-facing position, or working in the pediatric department.

CONCLUSION

The seroprevalence of pertussis of the HCWs of a university hospital in Korea was low, and there were some unrecognized acute infections. Therefore, booster immunization of pertussis to HCWs should be actively considered.

Preventing the Spread of Pertussis in Pediatric Healthcare Settings

The surge in pertussis incidence in recent years underscores a critical need for effective plans to prevent transmission in pediatric healthcare settings. Adolescents and adults are common sources of infection for unimmunized or incompletely immunized infants and children with waning immunity. Despite documented outbreaks being limited in size, pertussis poses a threat to pediatric healthcare facilities due to the risk for widespread transmission, potentially severe complications among vulnerable patient populations, and high outbreak control-related costs. Healthcare personnel, visitors, and parents have been identified as sources of outbreaks, underscoring the importance of coordinated efforts to prevent transmission in these settings. This comprehensive review demonstrates that the risk of pertussis transmission in pediatric healthcare settings warrants heightened focus on strategies to recognize disease earlier, improve diagnostic evaluation, and facilitate effective contact tracing and post-exposure prophylaxis measures. This review suggests that healthcare personnel can play a significant role in the prevention of healthcare-associated pertussis.

Pertussis vaccination for health care workers

Pertussis, an acute respiratory infection caused by Bordetella pertussis, classically manifests as a protracted cough illness. The incidence of pertussis in the United States has been increasing in recent years. Immunity wanes after childhood vaccination, leaving adolescents and adults susceptible to infection. The transmission of pertussis in health care settings has important medical and economic consequences. Acellular pertussis booster vaccines are now available for use and have been recommended for all adolescents and adults. These vaccines are safe, immunogenic, and effective. Health care workers are a priority group for vaccination because of their increased risk of acquiring infection and the potential to transmit pertussis to high-risk patients. Health care worker vaccination programs are likely to be cost-effective, but further research is needed to determine the acceptability of pertussis vaccines among health care workers, the duration of immunity after booster doses, and the impact of vaccination on the management of pertussis exposures in health care settings.

Outbreak of pertussis among healthcare workers in a hospital surgical unit

BACKGROUND

In September 1999, a pertussis outbreak was detected among surgical staff of a 138-bed community hospital. Patients were exposed to Bordetella pertussis during the 3-month outbreak period.

OBJECTIVE

To describe the outbreak among surgical staff, to evaluate implemented control measures, and to determine whether nosocomial transmission occurred.

METHODS

Clinical pertussis was defined as acute cough illness with a duration of 14 days or more without another apparent cause; persons with positive culture, PCR, or serologic test results were defined as having laboratory-confirmed pertussis. Surgical healthcare workers (HCWs) were interviewed regarding pertussis symptoms, and specimens were obtained for laboratory analysis. Patients exposed to B. pertussis during an ill staff member's 3-week infectious period were interviewed by phone to determine the extent of nosocomial spread.

PARTICIPANTS

A total of 53 HCWs assigned to the surgical unit and 146 exposed patients. HCWs with pertussis were defined as case subjects; HCWs without pertussis were defined as non-case subjects.

RESULTS

Twelve (23%) of 53 HCWs had clinical pertussis; 6 cases were laboratory confirmed. The median cough duration in the 12 case subjects was 27 days (range, 20-120 days); 10 (83%) had paroxysms. Eleven (92%) of 12 case subjects and 28 (86%) of 41 non-case subjects received antibiotic treatment or prophylaxis. Seven case subjects (58%) reported they always wore a mask when near patients. Of 146 patients potentially exposed to pertussis from the 12 case subjects, 120 (82%) were interviewed; none reported a pertussis-like illness.

CONCLUSIONS

Surgical staff transmitted B. pertussis among themselves; self-reported data suggests that these HCWs did not transmit B. pertussis to their patients, likely because of mask use, cough etiquette, and limited face-to-face contact. Control measures might have helped limit the outbreak once pertussis was recognized.

Bordetella pertussis detection by spectrofluorometry using polymerase chain reaction (PCR) and a molecular beacon probe

Bordetella pertussis was detected by spectrofluorometry following PCR incorporating a molecular beacon probe in the reaction. A DNA fragment from the tandem repeat sequence region (IS 481) of the genome of B. pertussis was amplified in presence of the probe complementary to an internal segment of the amplified DNA fragment. Fluorescein (FAM) and DABCYL were used as the fluorophore and quencher in the probe. The probe was characterized for its signal to noise ratio by homogeneous solution hybridization with a complementary oligonucleotide. Measurement of fluorescent signal at the emission maxima of FAM, immediately after a PCR was used to detect the B. pertussis target, with no additional steps. Presence of B. pertussis in a sample was also examined by agarose gel electrophoresis of the PCR product. A serial diluted stock of B. pertussis (ATCC strain #9797) and fourteen clinical isolates of B. pertussis were examined. The sensitivity of detection by fluorescent measurement was found to be at least in the range of 0.01-0.1 CFU per 10 microl of the sample and was equal to or better than that detected by agarose gel analysis.

Infections Associated with Health-care Personnel: Vaccine-preventable Diseases and Bloodborne Pathogens

Health-care personnel (HCP) are at risk for infection from occupational exposure, and can transmit infectious pathogens to patients and other personnel. The risk of disease acquisition depends on factors including the virulence of the causative organism, the mode of pathogen transmission, and the immune competency of the exposed individual. This article reviews the management of occupational exposure, infection, and strategies for the prevention of transmission of selected vaccine-prevent- able diseases (varicella zoster virus, influenza, pertussis) and bloodborne pathogens (hepatitis B virus, hepatitis C virus, human immunodeficiency virus). Recommended strategies include surveillance, vaccination, infection control measures, and postexposure prophylaxis. Improved detection, management, and prevention strategies are needed to reduce the risk of trans- mission of infection to HCP.