The Brazilian Navy said Tuesday that Influenza B was responsible for the hospitalization of 62 Marine Corps cadets in the past few days. The local naval hospital said seven cadets have tested positive for the virus, including some serious cases, such as 22-year-old cadet Leonardo Gama Rodrigues, who is being kept under observation in the intensive care unit. \"The cadets had acute respiratory syndrome, some with grave symptoms,\" Dr. Andre Delorenzi said, adding that Influenza B is spread by airborne transmission. Among the 57 cadets admitted to the naval hospital last week, 38 have been discharged and are currently quarantined in the Admiral Milciades Portela Alves Training Center (Ciampa). The other five cadets who were admitted on Monday and Tuesday remain in the hospital. Around 800 cadets and workers of Ciampa have got the flu shot, the Navy said. However, the Navy denied that the high number of hospital admissions had other causes, such as water poisoning, dehydration or excessive physical training. Nevertheless, relatives of the patients said that the cadets were submitted to intense physical training and received no water. Several cadets also said their drinking water was limited due to the supply problem and they had to drink tap water. They denied any abuse during the training.