Help please :(

I flew a lot today. Over the course of 24 hours, I've been to 4 different states on 3 different planes. From Washington, to Massachusetts, to New York and finally to Florida. Over the course of my trip, I noticed my entire chest broke out in blackheads. Like from everything to nothing. The pictures aren't very good but if you zoom in you can see. The pictures really don't do it justice, they're seriously everywhere and so many. Can anyone tell me why this happened and how to get rid of it? :( kinda ugly when you just get to Florida for vacation..