Suggest Treatment For Red Bumps Due To Bug Bite

have many bites on feet and some below the knee. The bites are non fluid filled, red, slightly raised, NON ITCHY,and are the size of the circles in the % mark. The tissue around the red bite becomes blanched when rubbed. Do not have fleas. Approx 30 bites for 3 to 4 days. What kind of bug could this be, or is it a s/s of a systemic disorder. 57y/o w/f 5'9" 205lbs. HX: HTN cozzar