The Wassermann reaction is a diagnostic test for the detection of syphilis.
It has low specificity, also testing positive in other infections:
Systemic lupus erythematosus
Ornithosis
Tuberculosis
Mycoplasma pneumonia
Malaria
Pregnancy
Infectious mononucleosis
Leprosy
Carcinomatosis
Measles
Toxoplasmosis
Chicken pox
Hepatitis
Yaws