The goal of this intervention study is to learn if giving children influenza vaccinations in early childhood education facilities (i.e., daycare) will increase vaccination coverage compared to giving vaccinations only at healthcare. The main question it aims to answer is:

• Does offering children nasal influenza vaccine in daycare result in higher proportion of children getting influenza vaccine.

Researchers will compare daycare setting and healthcare setting as the location of giving influenza vaccines to children to see if more children will get vaccinated if they have an opportunity to receive nasal influenza vaccine at daycare.

Participants in the intervention group will:

• Have the opportunity to receive influenza vaccine in the daycare or in the healthcare

Participants in the comparison group will:

• Have the opportunity to receive influenza vaccine in the healthcare only

Inclusion Criteria:

• Attending early childhood education (daycare) in the city of Turku

Exclusion Criteria:

• No exclusion criteria

According to national regulations, it is not allowed to share individual health data.