Horizontal transmission of HIV-1 infection in a child: With phylodynamic evidence-case study

Area of Science:

• Pediatric infectious diseases
• Viral phylodynamics
• Public health

Background:

• Mother-to-child transmission (MTCT) is the primary route of HIV infection in children.
• Nonvertical transmission, though less common, poses diagnostic challenges.
• This case involves a child with HIV born to an HIV-negative mother.

Observation:

• A 3.5-year-old child was diagnosed with HIV despite an HIV-negative mother.
• The child's paternal grandmother was HIV-positive.
• No other transmission routes were identified through initial history.

Findings:

• Bayesian phylodynamic analysis revealed a genetic link between the child's and grandmother's HIV strains.
• Evidence suggests HIV transmission from the paternal grandmother to the child.
• The specific route of postnatal transmission remains unidentified.

Implications:

• This case highlights the possibility of HIV transmission from infected relatives to children through uncharacterized routes.
• Further research into nonvertical HIV transmission modes is essential.
• Identifying and interrupting these transmission pathways can improve strategies to prevent pediatric HIV infections.