Secondary syphilis. Rash & inflammation on a foot due to an infection with syphilis. It is caused by infection with Treponema pallidum, a spirochaete bacterium, through sexual intercourse with an infected person. About 3-4 weeks after infection, a sore (chancre) appears at the infection site, healing within 2 months. About 6-12 weeks after infection secondary syphilis occurs. The main symptom is a skin rash, with headache, fatigue & fever. Tertiary syphilis follows within 10 years of infection; with the formation of tumour-like gummas causing neurological disorders. Treatment is with antibiotic drugs.