Patients with West Nile Virus may never fully recover from the illness, according to a new study released today at the International Conference on Emerging Infectious Diseases in Atlanta, Ga.
As many as 60 per cent of patients with severe symptoms still reported feeling ill after one year, and if they hadn't recovered by the two-year mark they most likely would not fully recover at all.
The study, which was conducted by researchers at the University of Texas Health Science Centre and included 108 West Nile patients from the Houston, Tex. area, also found that about 40 per cent of patients still had symptoms five years after their initial infection. Long-term damage included memory loss, loss of balance and tremors.
West Nile virus is usually transmitted to humans via a bite from an infected mosquito. While the majority of patients don't experience any symptoms, the study's subjects had symptoms ranging from fatigue and weakness to seizures, tremors and paralysis. Half of the study's patients had infection-induced encephalitis (inflammation of the brain), and another third had developed meningitis (inflammation of the lining of the brain or spinal cord). The type of symptoms a patient had influenced recovery.
"Those patients with encephalitis were less likely to recover than those who had meningitis or uncomplicated fever," said lead researcher Kristy Murray of the University of Texas Health Science Center in Houston.
Another long-term effect of the virus was depression. Thirty-one percent of patients reported having symptoms of depression for the first time, and the researchers found that 75 percent of them met the criteria for clinical depression.
West Nile virus season in Canada is from May to October, and Health Canada reports that the risk of contracting West Nile virus is small. Last year 2,353 cases were reported to the Public Health Agency of Canada. Simple precautions to protect against the virus include using insect repellents, staying indoors at dawn and dusk (when mosquitos are out) and ensuring that door and window screens on your home are fitted properly.
