Update on vaccination of preterm infants: a systematic review about safety and efficacy/effectiveness. Proposal for a position statement by Italian Society of Pediatric Allergology and Immunology jointly with the Italian Society of Neonatology.

Abstract

Introduction: Preterm infants (PIs) are at increased risk of vaccine preventable diseases (VPDs). However delayed vaccination start and low vaccine coverage are still reported. Areas covered: This systematic review includes 37 articles on preterm vaccination published in 2008-2018 in PubMed. Both live attenuated and inactivated vaccines are safe and well tolerated in PIs. Local reactions, apnea and reactivity changes are the most frequently reported adverse events. Lower gestational age and birth weight, preimmunization apnea, longer use of continuous positive airway pressure (CPAP) are risk factor for apnea. The proportion of PIs who develop protective humoral and cellular immunity is generally similar to full terms although later gestational age is associated to increased antibody IgG concentrations (i.e. against certain pneumococcal serotypes, influenza, hepatitis B virus and poliovirus 1) and increased mononuclear cells proliferation (i.e. after inactivated poliovirus). However vaccinated PIs have lower hospitalizations, ambulatory visits and notifications of VPDs. Expert opinion: PIs can be safely and adequately protected by available vaccines with the same schedule used for full terms. However data at this regard have been almost exclusively retrieved by studies using a 3dose primary series for pneumococcal and hexavalent vaccines, while further studies are needed regarding the 2+1 schedule. Apnea represents a nonspecific stress response in PIs, thus those hospitalized at 2 months should have cardio-respiratory monitoring for 2 days after their first vaccination.

Five Year Follow Up of Extremely Low Gestational Age Infants after Timely or Delayed Administration of Routine Vaccinations

“…International guidelines recommend administering immunization in preterm infants according to the same schedule as term infants [ 17 , 21 , 22 ]. A delay is frequently reported in this population [ 23 , 24 , 25 ], which can be confirmed by our observational data from German NICUs for approximately 10% of infants.…”

“…We speculate that the reasons include lack of knowledge and uncertainty of parents and healthcare professionals about the tolerability and efficacy of vaccinations in infants with higher prematurity-related risks for long-term morbidity [ 26 , 27 ]. The safety and effectiveness of immunization in preterm infants has been confirmed several times [ 21 , 28 , 29 ]. Historical skepticism towards schedule-based immunization in preterm infants might be related to the clinical aspects of increased vulnerability in ELGAN infants including SGA status, reduced muscle mass and surrogate measures of complicated courses, i.e., invasive treatments and requirement of prolonged medical support such as oxygen need at discharge.…”

Cardiorespiratory Events Following the Second Routine Immunization in Preterm Infants: Risk Assessment and Monitoring Recommendations

“…This finding favors the reduced schedule in preterm infants with the second rIM given at a chronological age of 4 months as applied in the United States of America and Australia [ 3 , 4 ] and implemented for term infants in Germany and Canada (2 + 1 schedule) [ 1 , 5 ]. However, most efficacy studies of immunization in preterm infants so far have been based on a three-dose primary vaccination (3 + 1 schedule) [ 7 , 43 , 44 ]. Further studies are needed to adopt a 2 + 1 schedule for preterm infants.…”

Carencias y variabilidad en la calidad de la atención a neonatos hospitalizados en México. Estudio transversal en 28 hospitales públicos

“…En particular, los niños con asfixia perinatal tendrían mayor probabilidad de daño irreversible 27 caso de deficiente oportunidad en diagnóstico correcto o vigilancia y control adecuado con monitoreo continuo de constantes vitales (frecuencia cardíaca, tensión arterial, saturación de oxígeno) y parámetros (uresis, glucosa, electrólitos, etc.). Sobre la importancia de vacunación en neonatos, hay consenso en la relevancia de combatir el retraso de la vacunación, especialmente en recién nacidos con prematuridad, 28 pues se exponen a enfermedades trasmisibles por las oportunidades perdidas de vacunación. Sin embargo, en los hospitales de este estudio la vacunación en neonatos parece no realizarse de forma rutinaria.…”