Evidence of hepatitis A virus person-to-person transmission in household outbreaks

PLoS One. 2014 Jul 22;9(7):e102925. doi: 10.1371/journal.pone.0102925. eCollection 2014.

Abstract

The person-to-person transmission of the hepatitis A virus primarily occurs in enclosed spaces, particularly in the presence of inadequate hygiene conditions and a high proportion of susceptible individuals. Thus, intimate family contact stands out as a risk factor for HAV infection dissemination. The present study aimed to evaluate the occurrence of household HAV transmission. Blood samples were collected from patients with hepatitis A (index cases) and their family members (contacts) that were referred to an ambulatory care clinic specializing in viral hepatitis. A total of 97 samples were collected from 30 families with a confirmed hepatitis A case (index case). Serological and molecular techniques for the diagnosis of hepatitis A were conducted on all samples. HAV infection (anti-HAV IgM + and/or HAV RNA +) was detected in 34.3% (23/67) of the contacts; 34.3% (23/67) of the contacts were immune to HAV, and 31.4% (21/67) were susceptible. In the household contacts, HAV immunity was significantly associated with older age; susceptibility to infection and HAV infection were associated with younger age. Household outbreaks were detected in 16/30 families studied. Co-circulation of subgenotypes IA and IB was found in the household outbreaks, and person-to-person transmission was evidenced in six of the household outbreaks, with 100% homology between the index case and contact strains. The results demonstrated the relevance of HAV household transmission, reaffirming the need for hepatitis A vaccine administration in susceptible contacts and effective infection control procedures to prevent the extension of household outbreaks.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Child, Preschool
  • Disease Outbreaks*
  • Family Characteristics
  • Family Health*
  • Female
  • Hepatitis A / epidemiology*
  • Hepatitis A / transmission*
  • Hepatitis A / virology
  • Hepatitis A Virus, Human / classification
  • Hepatitis A Virus, Human / genetics*
  • Hepatitis A Virus, Human / physiology
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Phylogeny
  • RNA, Viral / blood
  • RNA, Viral / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Young Adult

Substances

  • RNA, Viral

Associated data

  • GENBANK/KF357524
  • GENBANK/KF357525
  • GENBANK/KF357526
  • GENBANK/KF357527
  • GENBANK/KF357528
  • GENBANK/KF357529
  • GENBANK/KF357530
  • GENBANK/KF357531
  • GENBANK/KF357532
  • GENBANK/KF357533
  • GENBANK/KF357534
  • GENBANK/KF357535
  • GENBANK/KF357536
  • GENBANK/KF357537
  • GENBANK/KF357538
  • GENBANK/KF357539
  • GENBANK/KF357540
  • GENBANK/KF357541
  • GENBANK/KF357542
  • GENBANK/KF357543
  • GENBANK/KF357544
  • GENBANK/KF357545
  • GENBANK/KF357546
  • GENBANK/KF357547
  • GENBANK/KF357548
  • GENBANK/KF357549
  • GENBANK/KF357550
  • GENBANK/KF357551
  • GENBANK/KF357552
  • GENBANK/KF357553
  • GENBANK/KF357554
  • GENBANK/KF357555
  • GENBANK/KF357556
  • GENBANK/KF357557
  • GENBANK/KF357558
  • GENBANK/KF357559
  • GENBANK/KF357560
  • GENBANK/KF357561

Grants and funding

The authors have no support or funding to report.