Tomato Blight

If your tomatoes were in pots I would dispose of the soil, if in the ground just make sure you do not grow tomatoes or potatoes there for the next few years.

I've always taken a bit of a cavalier attitude to blight, until this year. I blamed the weather for the past two summers for blight devastating the outdoor crop. Now this year, in France at least, we've had almost unbroken hot and sunny weather.
Despite this, the blight has attacked the tomatoes in a polytunnel, although we've been able to crop them quite well. But now even the new growth on the plants is affected.
Outdoors I thought I'd escaped, but the plants are now showing signs of leaves browning etc., so I doubt we will be able to crop into the autumn.
I think plants can survive the blight longer in hot and sunny weather, but it's still there.
In future I'm going to take Moon grower's advice and clean up the debris from the polytunnel properly and grow the tomatoes in a completely new spot outside. I'm sure that's the only way.
The other thing to do is to eliminate any potato sports (potatoes growing from bits of tuber) as the blight can survive from one year to the next on these.