Immunisations for premature babies

Talia had her 18 month vaccination this week - the regulation shot against chicken pox, but also an extra dose of Hepatitis B vaccine. I hadn’t realised until I opened her purple health record book that morning that there was a handwritten amendment to her vaccination schedule indicating that she needed this additional shot. The nurse at the central immunisation clinic at Rheola Street told me that it was due to her extremely low birth weight and that babies born under 1000g require this extra shot.

Then I found the following information online at http://www.immunise.health.gov.au Common questions on getting immunised I have highlighted the vaccines they mention.

Premature babies especially need the protection of immunisation because they are more prone to certain infections. In general, babies born prematurely receive the same immunisations as other babies. However, very low birth weight babies may have a lower response to hepatitis B and Hib vaccine. The immunisation requirements of a very low birth weight baby should be discussed with your paediatrician and may include having their antibody response checked after immunisation, a delayed immunisation or an extra dose of the hepatitis B and Hib vaccine. As well, premature babies born at less than 28 weeks gestation require an extra dose of Hib vaccine and pneumococcal vaccine.

So Talia’s hepatitis B has now been taken care of, but what is supposed to be happening with regard to Hib and pneumococcal?

I borrowed a copy of the Australian Immunisation Handbook, 2008 edition and the answers (text taken either directly from the book or summarised as accurately as possible) are as follows:

A fourth dose of Hib vaccine is recommended for preterm babies born 28 weeks gestation or earlier, 1500g or less, if they are vaccinated with PRP-OMP. When other Hib vaccines, including Infanrix hexa, are used, no change in the usual schedule is required. [p136] So if you’re prem and in Perth, you don’t need to do anything because the WA government uses Infanrix hexa (DTPA-IPV-HepB-Hib) for Hib vaccination at 2, 4 and 6 months, plus there is a single Hib shot at 12 months.

All preterm babies born at less than 28 weeks gestation or with chronic lung disease should be offered the 7-valent pneumococcal conjugate vaccine (ie the current pneumococcal vaccine for babies and young children) at 2, 4 and 6 months of age (as per the schedule), with a fourth dose at 12 months of age, and a 23-valent pneumococcal vaccine (the older standard pneumococcal vaccine) booster at 4-5 years of age. [pp89, 244-247] So I need to arrange for Talia to have this fourth dose.

Preterm babies do not respond as well to hepatitis B-containing vaccines as term babies. Thus for babies born at less than 32 weeks gestation or less than 2000g birthweight, it is recommended to give vaccine at 0, 2, 4 and 6 months of age, and give a booster at 12 months of age (unless antibodies are measured and found to be in high enough concentrations).[p157] This is the booster which Talia ended up having this week, at 18 months.

In case you were wondering, Talia has never had any problems with any of her vaccinations. She wails indignantly for about 10 seconds, and then the nurse blows a stream of beautiful bubbles and distracts her completely.