[Active and passive immunization in the extremely preterm infant]

Area of Science:

• Pediatric Infectology
• Neonatal Immunology
• Vaccinology

Context:

• Extremely preterm infants and very low birth weight newborns represent a vulnerable population with unique immunological considerations.
• Current knowledge regarding the immunogenic efficacy and reactogenicity of vaccines in this group is limited, leading to potential delays or omissions in immunization.
• Pediatricians face challenges in determining optimal immunization strategies for these infants.

Purpose:

• To review the indications, contraindications, optimal timing, immunogenic efficacy, and adverse events of active and passive immunization in extremely preterm infants.
• To synthesize available evidence on vaccine and immunoglobulin administration for this high-risk neonatal group.

Summary:

• Despite limited data, clinically stable extremely preterm infants should generally follow the same immunization schedule as full-term infants, regardless of birth weight or gestational age.
• Active immunization programs for preterm infants can largely mirror those for full-term infants, with few exceptions like the BCG vaccine.
• Passive immunization strategies may require more liberal application in extremely preterm and very low birth weight newborns.

Impact:

• Provides guidance for pediatricians on the immunization of extremely preterm infants, aiming to improve vaccine uptake and adherence to schedules.
• Highlights the need for further research into the specific immunological responses and safety profiles of vaccines in this population.
• Emphasizes the importance of tailored passive immunization approaches for enhanced protection in vulnerable newborns.