Diphtheria in a Swiss Asylum Seeker Reception Centre: Outbreak Investigation and Evaluation of Testing and Vaccination Strategies

Int J Public Health. 2024 Apr 24:69:1606791. doi: 10.3389/ijph.2024.1606791. eCollection 2024.

Abstract

Objectives: To describe a suspected diphtheria outbreak in a Swiss asylum seeker reception centre, and to analyse its management response regarding testing and vaccination. Methods: We retrospectively analysed clinical, microbiology, and case management data of all asylum seekers tested for C. diphtheriae between 28th August and 31st December 2022 while residing at the centre. Results are reported descriptively. Results: Among 265 individuals tested, ten cases of cutaneous diphtheria, one simultaneous respiratory and cutaneous case, and nine respiratory carriers were identified. Mass throat screening, targeted throat testing and targeted wound testing yielded 4.8%, 4.3%, and 17.4% positive results, respectively. No respiratory carrier was identified among cutaneous cases undergoing a throat swab, and no symptomatic case was identified among individuals with unspecific throat symptoms. Rates of vaccination implementation of newly arriving asylum seekers before and after the outbreak were low (17.5% and 15.5%, respectively), as were rates of targeted vaccination among cases and close contacts. Conclusion: We provide evidence for transmission both prior to arrival and within the setting, suboptimal practices and timeliness of testing, and implementation gaps in vaccination.

Keywords: asylum seeker; corynebacterium diphtheriae; diphtheria; migrant; outbreak.

MeSH terms

  • Adolescent
  • Adult
  • Corynebacterium diphtheriae
  • Diphtheria* / epidemiology
  • Diphtheria* / prevention & control
  • Disease Outbreaks* / prevention & control
  • Female
  • Humans
  • Male
  • Mass Screening
  • Middle Aged
  • Refugees* / statistics & numerical data
  • Retrospective Studies
  • Switzerland
  • Vaccination / statistics & numerical data
  • Young Adult

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. NL received an Eccellenza Grant from the Swiss National Science Foundation (PCEFP3_181355).