Public Health England (PHE) data suggest that the nasal spray flu vaccine, used for children aged two to seventeen years against influenza A(H1N1)pmd09, is 87% effective. The vaccine given to adults aged 18 to 64 in at-risk groups is estimated to be 39% effective against the same strain. Influenza A(H1N1)pdm09 has been the main strain circulating this season.
More children have been vaccinated than ever before this season, with over five million children in the year five school group being offered the nasal spray. Protecting younger children, who have poorer hand and respiratory hygiene than adults, is necessary in order to protect the rest of the population as they tend to spread flu more easily.
Vaccine uptake in children aged two and three years-old is 43% and 45.2% respectively, while among school-aged children, ranges from 56.2% to 63.9%, depending on year group.
Source: UK Government, 22 February 2019