(CNN)Most European countries have Covid-19 vaccination rates that would be the envy of much of the world. But even here, hesitancy in certain areas is causing governments to take action -- or risk stalling their efforts to control the spread of the virus.
The highly transmissible Delta variant and concerns that winter in the northern hemisphere could bring a bad flu season have increased the urgency for authorities to boost vaccine uptake.
Reasons for hesitancy are varied. Some people believe they are fit, healthy and young, so getting vaccinated is not a priority. Some found it too complicated to book a vaccine so gave up. And some simply distrust their government to the extent that they've become susceptible to misinformation.