USNS COMFORT U.S. Public Health Service Lt. Cmdr. Gregg Langham and U.S. Army Sgt. Leona Thomas, both attached to the USNS Comfort, inject cattle with anti-parasite and tetanus vaccinations at the Dos Potrillos Ranch in Villanueva, Nicaragua, July 22, 2007. SHARE: Download: Full Size (0.04 MB) Credit: VIRIN: 151203-W-VLY08-515.jpg Photo Gallery