True about syphilis is A/E – a) VDRL is sensitive but not specificb) Infection leads to life long immunityc) IgM & IgAd) T. pallidium when inoculated in rabbit produce progressive disease

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.