Dawson was among a number of England players, along with Martin Corry, Mike Tindall and Steve Thompson as well as replacements Tom Voyce and Lee Mears, to be hit by a stomach bug ahead of the emphatic defeat at the Stade de France.
However, the Wasps scrum-half insists he would not have played if he had not felt up to it.
Dawson told BBC Radio 5 Live: "We'll not use it as an excuse. We were not up to it, our skill level wasn't where it should have been.
"I wouldn't have played if I wasn't feeling anywhere near 100%. I was not feeling 100% in the middle of the night but come 1 or 2pm I felt pretty good.
"The beginning of the game was a little bit nervy but as soon as the adrenalin is pumping you are off and running.
"There is more to be worried about than a couple of players feeling dodgy."
The defeat was England's seventh in 14 RBS 6 Nations games since they won the World Cup and it equalled their worst margin of defeat against France