(ANSA) - Cagliari, September 7 - Two elderly people were hospitalized in grave condition Friday having contracted West Nile virus in Cagliari, on the Italian island of Sardinia. Both were transferred Friday morning to the intensive care unit of the Santissima Trinita' di Cagliari hospital after their conditions worsened. One patient, 79, is a resident of the town of Nurachi on the western coast of Sardinia. The other patient, 83, lives in Narbolia, also on the western coast of Sardinia, about 10 kilometers south of Nurachi. Roughly 20% of those infected with West Nile virus develop West Nile fever, according to the United States Center of Disease Control. Symptoms include fever, headache, tiredness, body aches, skin rash on trunk of the body, and swollen lymph glands. Approximately 1 in 150 develop severe disease that can lead to high fever, stupor, coma, tremors, convulsions and paralysis. Severe symptoms occur more often in the elderly and people with compromised immune symptoms.