Don’t let the bed bugs bite
Ordinary urticarial lesions come and go within six to eight hours but the lesions of papular urticaria persist. Always consider insect bites as the cause. In a tourist such as this, bed bugs were the likeliest cause. They arise within 24–48 hours after being bitten and the size of the lesions is determined by the level of your immune response. Always check for any evidence of scabies because highly allergic patients can also present like this. Most cases of papular urticaria occur after flea bites from household pets but convincing patients of this can be difficult.