BMR-0

Background and objective of the study

In light of the measles epidemic, the Outbreak Management Team (OMT) has advised that all children aged 6 to 14 months, who live in a district with a vaccination coverage below 90%, are offered early MMR (Measles, Mumps and Rubella) vaccination. For children under 12 months of age, this will be an extra vaccination. The BMR-0 study will investigate the effectiveness of this early MMR vaccination against clinical measles. In this way, it can be determined after the outbreak, which factors played a role in protection against measles and what the effects are on the immune response.

Who is being invited?

All children eligible for the early MMR vaccination will be invited to participate in this study.

What does the study involve?

When parents enrol, they will receive an e-mail with a link to an online questionnaire. We also ask parents to inform us when their child has any signs and symptoms of measles. In case of a possible measles infection, parents recieve a saliva test that they can take from their child themselves. In the saliva we will assess antibodies against measles. At the same time, parents will also receive a link to a follow-up questionnaire.

Follow-up study

In a small subset of participating children, we will investigate the influence of the early MMR vaccination on the immune system. In this way, we can look at the effect of early vaccination on the immune response against measles , but also at the effect on the other vaccines in the National Vaccination Program, such as mumps, rubella and whooping cough. To do this, blood will be taken during home visits. Parents can consent to this part of the study separately.

Start and duration of the study

All eligible children have been invited for vaccination. Every upcoming week, new children who have reached the age of 6 months will be contacted. This system will be used for the full duration of the epidemic. Parents will be given sufficient time to decide whether they wish to have their child vaccinated, before they receive an invitation to participate in this study. Invitations for participation in the study will be sent four weeks after parents received the vaccination call. The study starts August 12th and runs until the end of the outbreak.

Who is carrying out the study?

The study is being carried out by the RIVM.

Questions?

For questions about the study, please contact the investigators at BMR-nul@rivm.nl.

BMR-1

Study objective

The objective of the BMR-1 study is to define which level (titer) of antibodies gives protection against measles. Data in the medical literature on this subject are very scarce. To be able to determine the protective titer, it is necessary to take blood samples before exposure. This can only be done in special circumstances, such as during the current measles epidemic in the Netherlands.

Who is being invited?

The aim is to include 750 children, who have received one dose of MMR vaccine in the study, and are likely to be exposed to measles. The focus of the study is therefore on children who are attending orthodox church schools in districts with a low vaccination coverage. The risk of measles in once-vaccinated children is very small (about 2% in case of direct exposure). If these children do contract measles, it is usually mild, because they often have some immunity. In addition, there is a relatively low risk of complications in children at the primary school age.

How are parents approached?

About 7000 parents will be approached in two ways. Directly through schools on the initiative of the GGDs. Parallel to this, a mailing will be sent from Praeventis, the national registration system of the vaccination program. In a number of postal code areas with a low vaccination coverage, all parents of children who have been vaccinated once, will be approached.

What does the study involve?

The parents who are approached through Praeventis, will be asked to fill in a short questionnaire on the Internet. Based on the information from the questionnaire, some of the parents will be invited to let their child take part in a follow-up study. This involves blood testing. The group that is not eligible for blood testing, will be asked to fill in a questionnaire twice, with an interval of a few months. The group that is eligible for blood testing, will be asked to consent to the collection of blood and saliva on two occasions. They will also be asked to fill in the questionnaire twice.

Start

The study starts week 29 with a pilot at 5 schools in the GGD areas of Midden Nederland, and 6 districts (Barneveld, Ede, Nunspeet, Scherpenzeel, Woudenberg, and Neder-Betuwe). After the summer holidays, other areas might be approached.

Who is carrying out the study?

The study is being carried out by the RIVM, in cooperation with GGD Midden Nederland and the Erasmus Medical Centre.

Questions?

For questions about the study, please contact the investigators at BMR1@rivm.nl.