Ptarvo fever is the Cardassian equivalent of Human "spring fever".
In 2372, Gul Hidret claimed to Benjamin Sisko that the Cardassians required the geset found on Cha'Xirrac to treat Ptarvo fever, which Hidret explained to Sisko as a disease which "decimates" young Cardassians. Odo was able to tell Sisko the true meaning of Ptarvo fever. Hidret also told Gordek that geset was needed to cure Ptarvo fever, although Kira Nerys described it to Gordek as "about as lethal as foot cramp". Hidret's real aim was to obtain the drevlocet from Cha'Xirrac. (DS9 - Day of Honor novel: Armageddon Sky)