"but other vaccines can contain other ingredients, like aluminium, to make them stable or more effective. "
"The data so far is reassuring - trials on 43,500 people discovered no safety concerns, although mild side effects, such as headaches and muscle aches, have been reported.
If there were highly dangerous and common consequences of this vaccination, they should have become apparent.
However, rarer side effects may emerge as millions of people are immunised."
"The announcement gave us the headline, but there is a still lack of fine detail.
We do not know if the vaccine stops you catching and spreading the virus or just stops you from getting ill. We also don't know how protective the vaccine is in different age groups.
These will be crucial for understanding how it will be used."