Also climbing with this Mr. Kainscaid would be good mosquito repellent considering his foul language would kill any airborne bug within 64.3 feet. If he used the F word more, it could extend the range considerably, but his viciousness more than compensates for that defect.
Climbing with someone who guzzled a half rack of Schmit Ice the day before is also effective, but in a more limited area. The odor from their exit chute is generally sufficient repellent for around camp, but not on the move.