Boris Johnson speaking at Downing Street coronavirus press briefing

The UK national vaccination program has surpassed its target, with over 15 million people vaccinated. Key contributors include healthcare professionals and volunteers. Despite vaccinating over 90% of those over 70, the threat of COVID-19 remains, as 60% of hospitalized patients are under 70. The effectiveness of vaccines in reducing infection spread is still being studied, and infection levels remain high.

What concerns are raised about the effectiveness of the vaccines?

What does the text suggest about the current level of infection and its implications?