<prompt> True about syphilis is AE a VDRL is sensitive but not specificb Infection leads to life long immunityc IgM IgAd T. pallidium when inoculated in rabbit produce progressive diseaseacbcad  <response>: Infection with syphilis does not provide life long immunity reinfection with syphilis is not uncommon especially in patients who have been treated early.Non-specific serological tests measure IgG IgM not IgM IgA.Intradermal and intraperitoneal inoculation of T.pallidum into experimental rabbit produce progressive lesions.VDRL is a sensitive test with sensitivity upto 100 in secondary syphilis. But it is not specific as nontreponemal antigen is used, infact it is one of the non-specific test for diagnosis of syphilis. 