Methotrexate is an antimetabolite used to treat certain types of cancer.
The largest rise was in secondary school children as the new term started, according to the ONS.
One man injected with the modified cold sore virus saw his tumour completely disappear.
The money is part of a package of measures to support NHS and care system this winter, ministers say.
Other groups have reported higher protection, but the results are still seen as a triumph.
A question everyone's asking: what's my Covid risk? Here's how to find out.
Borrowing - which hit a record £22.3bn in October - cannot go on indefinitely, chancellor says.