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Real-Time Polymerase Chain Reaction-Based Detection and Quantification of Hepatitis B Virus DNA
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Real-Time Polymerase Chain Reaction-Based Detection and Quantification of Hepatitis B Virus DNA

Published on: December 15, 2023

Case-control study of risk factors for abscess development following hepatitis B vaccination in children in

Mariano da Silva Marques1,2, Filipe de Neri Machado1, Marcelo Amaral Mali1

  • 1Instituto Nacional da Saúde Pública, Dili, Timor-Leste.

Plos One
|June 22, 2026
PubMed

Insights

A study in Timor-Leste found no significant risk factors for infant injection-site abscesses after hepatitis B vaccination. Due to a small sample size, findings are hypothesis-generating, emphasizing improved injection practices and surveillance.

Area of Science:

  • Public Health
  • Immunization Practices
  • Pediatric Infectious Diseases

Background:

  • Hepatitis B vaccination is crucial for preventing chronic infection.
  • A high proportion of adverse events following immunization (AEFI) in Timor-Leste involved injection-site abscesses in infants receiving the birth dose.
  • Understanding abscess formation factors is vital for improving immunization safety.

Purpose of the Study:

  • To explore potential factors associated with injection-site abscesses following hepatitis B birth-dose vaccination in infants.
  • To inform improvements in immunization practices in Timor-Leste.

Main Methods:

  • Retrospective matched case-control study in Timor-Leste.
  • 12 infant pairs (cases with abscesses, matched controls) were analyzed.
  • Data collected via caregiver interviews, record reviews, and facility assessments.

Main Results:

  • No statistically significant associations found between examined variables and abscess formation.
  • Extremely wide confidence intervals due to small sample size (12 pairs).
  • Findings are descriptive and hypothesis-generating, not confirmatory.

Conclusions:

  • This study did not identify significant risk factors for injection-site abscesses after hepatitis B birth dose.
  • Small sample size limits inferential capacity; findings are exploratory.
  • Strengthening safe injection practices, vial management, and AEFI surveillance is critical; larger studies are needed.
Abstract

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