Thanks for writing to us.
It seems your wife developed insect bite induced cellulitis
along with lymphangitis( red streak going up her leg). To treat the same she should take a course of oral antibiotic along with antiinflammatory analgesic
and a topical antibacterial cream. She should give rest to affected leg too.
I would advise that you visit a doctor nearby to get the prescription for above medicines.
Hope that helps. Take care