Vaccinating preterm infant
Does preterm babies need to be vaccinated
Yes preterm babies must be given vaccine as per the schedule and according to the chronological age. The vaccines wont harm them as they can mount an immune response and they need protection specifically for diseases like pertussis (Whooping cough).
When should they receive their first vaccine
We don’t need to correct for prematurity and most of the vaccines can be given as per the chronological age eg if a baby was born at 30 weeks gestation the day of birth should be counted as day 0.
How safe and effective is the vaccine
Immunisation in these infants is safe and effective. Some infants may develop post-vaccination apnoea (Cessation of breathing) with or without associated drop in heart rate up to 48 hours post-immunisation. Therefore they may need to be observed in the hospital specifically in case of DPT Vaccine.
Are there any modifications from the routine Schedule in the case of preterm baby
BCG vaccine should be given at 34- 35 weeks gestation as the immune response is better. Babies <2 kg may need an additional dose of Hepatitis B vaccine. The schedule may vary in individual cases.
In mothers with an unknown HBsAg positivity status at delivery, the birth dose of hepatitis B vaccine is administered within 24 hours of birth, and HBIG is administered as soon as possible if the mother tests positive, ideally within 72 hours of delivery [2,18].
In the case of preterm babies of HBsAg positive mothers, the birth dose is indicated even if the baby weighs less than 2 kilograms, but should be followed by a further three doses starting at six weeks of age [21,22]. This is due to the reduced immunogenicity of hepatitis B vaccine in preterms weighing <2 kilograms in the first month of life [23].
The immunogenicity of hepatitis B vaccine is suboptimal in conditions associated with immuno-suppression, including advanced HIV infection, and is influenced by the viral load, CD4 count, age, duration of HAART and the presence of AIDS defining conditions [18]. Hence, early administration of the hepatitis B vaccine starting at birth is imperative, since immunosuppression increases over time [18].
Interruption of the vaccine series does not warrant revaccination, but rather completion of the missed dose as early as possible with a minimum interval of four weeks between two doses [24].
Women who are HBsAg negative in pregnancy, but who are at high risk of acquiring hepatitis B infection, including those with a history of multiple sexual partners or of drug abuse, should receive hepatitis B vaccine [24].
Author: Dr. S. Boopathi MD, DNB, MRCPCH(UK)
