Babies born early - antibody response to Men B vaccination.
Meningococcal bacteria are an important cause of meningitis and septicaemia in the UK. There are several strains of these bacteria and vaccines are available to protect against infection caused by some, but not all, strains.
In the UK, babies are vaccinated according to the same schedule whether they are born early (preterm) or on time. However, there are concerns that preterm babies may not respond as strongly to their vaccinations and this may result in less protection. In 2015, a new meningococcal group B (MenB) vaccine (Bexsero) was introduced into the routine immunisation schedule. There is currently no evidence as to whether this will work as well in preterm babies compared with babies born on time. This project will compare responses made by babies who are vaccinated according to two different schedules and could help inform decisions about what programme should be followed for preterm babies.
This work is partially funded by Meningitis Now, with the balance of funding provided by GSK.
What the research team planned to do
136 preterm babies were recruited from six sites in the UK and over 90% went on to complete their participation in the study. Each baby was randomly assigned to one of two study groups; one group receiving the MenB vaccine at two and four months of age, and the other group receiving an additional dose at three months. All babies received a booster dose at 12 months of age. Blood samples were taken from all babies at five, 12 and 13 months of age to assess the antibody levels induced by the vaccine. Parents/carers were also asked to complete diary cards to record any side effects such as fever or local reactions at the injection site.
Summary and impact of results
The research team has shown for the first time that overall, premature babies who received either of these schedules of MenB vaccination were satisfactorily protected against Men B disease at five, 12 and 13 months of age. This includes even very premature babies. There were some differences according to the schedule, with those who received an additional dose of vaccine having higher antibody levels to some aspects of the vaccine, as well as slightly more fever. Further analysis will investigate these results in more detail.
These differences may be important, but will depend on when MenB disease is mostly a problem for young infants, and this will vary in different populations.
However, we can be confident that this MenB vaccine is able to safely protect premature infants in the UK setting.