A recent study from researchers at Baylor College of Medicine suggests that West Nile virus is associated with death even after patients have recovered. Most people who become infected do not have any symptoms and the majority who do have an acute febrile illness characterized by a fever with symptoms such as headache, body ache, vomiting, joint pain, diarrhea, or rash. Most of these patients fully recover. A small percentage of patients develop meningitis or encephalitis. However, this study found that many patients who fully recovered then died from seemingly unrelated reasons, mostly from other infections or kidney failure.
13% of 4,144 Texans who were infected with West Nile virus from 2002 to 2012 died. 7% of the infected patients died within 90 days of the infection. Notably, 210 patients who had severe symptoms died after they seemingly recovered. Patients under 60 years of age had a risk of dying from kidney failure that was 11 times that of the general population of that age group.