Vaccinations in preterm infants: Which and when?

Area of Science:

• Pediatrics
• Immunology
• Public Health

Background:

• Preterm infants (10% of global births) have immature immune systems, increasing infection susceptibility.
• Reduced maternal antibody transfer further compromises their defense against pathogens.
• Current immunization guidelines based on chronological age are often not met in preterm infants, leading to delayed or incomplete vaccination.

Purpose of the Study:

• To review current evidence on vaccine safety, efficacy, and optimal timing for preterm infants.
• To emphasize primary immunizations and vaccines during the first year of life.
• To explore novel strategies for enhancing vaccine responsiveness in this population.

Main Methods:

• Comprehensive literature review of studies on preterm infant immunization.
• Analysis of immunological characteristics affecting vaccine response.
• Evaluation of emerging vaccine technologies and approaches.

Main Results:

• Preterm infants exhibit distinct immunological traits, including impaired T- and B-cell responses and altered microbiome development, leading to reduced vaccine responsiveness.
• Evidence on vaccine safety and efficacy in preterm infants is summarized, with a focus on primary immunization schedules.
• Emerging approaches show promise for improving vaccine efficacy.

Conclusions:

• Timely and complete immunization is critical for reducing preventable infections in preterm infants.
• Novel strategies like mRNA vaccines, adjuvants, maternal immunization, and microbiome modulation offer potential to enhance vaccine efficacy.
• Adherence to vaccination recommendations is essential for the health of this vulnerable group.