It was a bumper crop of flies in Leran this summer. Although we only have one summer to compare it to, this notion was confirmed by numerous others. That's scientific enough for me. I don't know the explanation for the plague, but hopefully it has passed on to some other deserving village.
There are few screens on windows here, except for an occasional homemade one. If you consider that every window on the village houses would require a custom-sized screen, maybe swatting a few flies is easier. But this summer one could develop rotator cuff problems. And our first French fly swatter broke off bit-by-bit with each hit, a somewhat lacking quality in a weapon. Neighbor Alan donated what he promised to be the 'end-all-be-all' in fly swatters, but for every one we kill another appears. It is questionable whether we were helping or hindering the problem.
In summer, the doors of the old timer Leranaise (and early-adopter newbies) are distinctively decorated with jangly curtains. The mouche rideau---fly curtain. It reminds me of my old hippie days. Some look like giant soft pipe cleaners, others are multi-colored plastic strips, beaded glass or metal chains. Some boast colorful patterns of flowers, farm animals or pastoral scenes. They shimmer in the sun, blow in the breeze, get caught in the doorway and break off. But they swear by them. Even once I saw an elderly neighbor inadvertently (I think) smoking the end of one strip in his pipe. Lucky for him, it was the 'pipe cleaner' variety.
We must fall into the category of laggards, since we have not yet succumbed. I was just waiting until I found a "Worst.President.Ever" mouche rideau.