Hepatitis B vaccination in preterm infants

Preterm infants, especially those with very low birth weight, are at risk of hepatitis B virus infection. They often require invasive diagnostic methods in their first weeks of life, intensive treatment and long-term hospitalisation. Therefore, hepatitis B vaccination is particularly justified in these patients. Our aim was to determine the reaction of preterm children to hepatitis B vaccination. The study comprised 64 preterm children whose birth weight ranged from 700 g to 2460 g (mean 1776.6 g ± 480.4 g) and whose gestational age was between 25 and 36 weeks. A 10 μg dose of the recombinant vaccine Engerix-B (SmithKline Beecham) was given at intervals of 0, 1, 2 and 12 months. In 49.2% of the children vaccination was administered on the 1st day of life, and in the remaining cases between the 2nd and 119th days post delivery. One month after vaccination completion the levels of anti-hepatitis B surface antigen (HBs) antibodies were evaluated. In 98.4% of the vaccinated preterm infants the level of antibodies was >10 mIU/ml. Mean level of anti-HBs antibodies in the group of children with birth weight ≤ 2000 g was 2431.4 mIU/ml, while in those with birth weight >2000 g it was 4803.9 mIU/ml. In children with a birth weight ≤ 1000 g, the mean level of anti-HBs antibodies was significantly lower than in those with birth weight >2000 g. The level of anti-HBs antibodies in children who started vaccination >1st day of life was significantly lower in preterm children with a birth weight ≤ 2000 g than in those with a birth weight >2000 g.