We've gotten it in March. It doesn't seem to affect everyone; three out of six of us got it. Two of the people who didn't get it used oil to tan, so I think it's a barrier thing. It's a very itchy and unpleasant-looking rash, and it's agony if you're sunburned. The "sting" itself isn't bad, a little stronger than no-see-ums, if you know those.