Velmoc flu was an ailment native to the planet Velmor. It apparently had some ties to the native Velmoc from that planet. After the disease had been beaten, the individual would then have a natural immunity to catching the Velmoc flu a second time. Prince Denid contracted the disease during his exile on Tantajoc V, but he survived. Following his return to Velmor, the royal physician, Chozz Wardle noted that Denid had beaten the disease in his report, which helped confirm that Denid was, in fact, the real crown prince.