Otashak, qarhai z u h r a v i, reshi narm (Ulcus nishe), dardi guzarandai zukhravi yo jimoi, ki az siroyati streptobasillai Petersen- Dyukrey-Unna asosan badi aloqai jinsi ba vujud meoyad. Padidahoi Otashak ba sifilis (bemorii kuft yo obidam farangi) shabohat dorad; az in sabab in du dardro vaqthoi pesh az yakdipar farq karda nametavonistand.
Badi 2—5 ruz dar on jon badan, ki barangezanda daromadaast, lankai surkhi ravshan paydo meshavad, ki varamida rikhinaki rimnok paydo mekunad. Pas az 3—4 ruz rikhinak kafida, ba qarhachai dardnoki kanorhoyash nohamvoru tagash «koftagi» mubaddal meshavad. Rui vayro parda megirad, tagash muloim, girdogirdash surkhi varamnok meshavad. Siroyati Otashak ba boftahoi atrofi qad- kashak pahn shuda, reshhoi nav paydo mekunad.
Soni guddahoi limfavii atrof ba kasali duchor gardida, varam mekunand va ba bodiring monand meshavand, ki vayro kh i yo r a k (bubon) mekhonand; gullaho ba yakdigar, inchunin ba pust sakht mechaspand, muloim shuda mekafand va parda paydo mekunand; dar in hol joi kasali dardnok, harorat baland va bemor ba ahvoli nokhushe meaf- tad.
M u o l i j a: istemoli doruhoi ziddibakteriyavi; joyhoi dardnokro bo obi shirgarmi makgannok vanna (obzan) kardan.