Study to evaluate prevention of meningococcal carriage in teenagers (SPIT)
Understanding whether the MenB vaccine has an effect on carriage in teenagers
Adam Finn, Caroline Trotter, Hannah Christensen, Jennifer Oliver
- Start Date:
01 September 2016
Bristol University, Bristol, UK, University of Cambridge, Cambridge, UK
What is the study about?
The meningococcal C (MenC) vaccine, introduced in 1999, has greatly reduced cases of meningitis and septicaemia caused by MenC infection in the UK. But disease due to meningococcus B (MenB) still occurs. Most infected people do not get the disease, but ‘carry’ meningococcal bacteria in their throats for up to several months; teenagers carry these bacteria more commonly than other age groups. The MenC vaccine was successful largely because it stopped people carrying and spreading the bacteria producing a ‘herd protection effect’.
A MenB vaccine was introduced for babies in September 2015 to protect vaccinated babies, but this programme will not protect older children and adults. The key to protecting the whole population could be immunising teenagers, since they are the age group most likely to harbour the infection, but only if it stops them carrying the bacteria.
This study aims to provide a better understanding of how scientists can best design vaccine studies investigating herd protection effects in future by looking at new sampling and testing techniques, more frequent sampling and the practicalities of conducting a vaccine study using these techniques in schools. It’s hoped that applying these methods in this study may also provide some initial indications of whether the MenB vaccine is likely to affect carriage and transmission of meningococcus in teenagers.
The study will recruit Bristol students aged at least 16 years at participating 6th form centres; some will be carrying bacteria at the start of the study, and some will not be carriers. Each student will be given two doses of MenB vaccine, and will be followed up for about 6 months. They will be asked to give a throat swab sample 3 times over the study and saliva samples once a week (during term time periods).
The team will describe the pattern of how many meningococcal bacteria are carried by the students and see if testing repeated saliva samples gives valuable results over and above those obtained from conventional, less frequent throat swab samples. They will also look at whether it is likely that the MenB vaccine is having an effect on these patterns of carriage, and finally they will ask the students to give feedback on how the study was run. The information gathered will help scientists to design a bigger study that will be able to answer these questions for sure.
Why is it important?
Scientists really need to understand whether the MenB vaccine has an effect on carriage in teenagers. If it does, this could completely change the way the vaccine is used.
Giving the vaccine to teenagers to prevent them from unwittingly spreading the bug around could unlock protection for the whole population.
This project also has support in kind and some financial support from: Clinical Research Network (CRN) West of England, National Vaccine Evaluation Consortium (NVEC), University Hospitals Bristol NHS Foundation Trust (UHB) and NIHR Health Protection Research Unit (HPRU).
The expected outcomes in the short term are:
- Information on the costs and operational aspects of the study, including an understanding of what worked well and what needs to be improved
- Information on whether students are willing to take part in the study, what they liked and didn’t like about taking part
- Knowledge of whether collecting and testing saliva is a convenient and accurate way of measuring carriage with potential to reduce the size and /or increase the power of intervention studies
- The study may generate evidence about the effect of MenB vaccines on carriage
In the longer term, the information from the study will be used directly to inform the design of a larger, definitive study of the effect of MenB vaccines on meningococcal carriage. The Department of Health has committed to funding this definitive study.