Good long-term prognosis after West Nile virus infection

Aug 18, 2008

The long-term prognosis of patients infected with West Nile virus is good, according to a new study appearing in the August 19, 2008, issue of Annals of Internal Medicine, the American College of Physicians' flagship journal. This is the largest study of the long-term outcomes of West Nile virus infection.

West Nile virus is a potentially serious central nervous system infection spread by mosquitoes. Many people infected by West Nile virus never get sick, so the disease can be difficult to diagnose. However, approximately 20 percent have symptoms that range from mild flu-like illness to neurological problems such as meningoencephalitis, encephalitis, and acute flaccid paralysis. Recent studies report that troublesome symptoms such as fatigue, cognitive dysfunction, and motor abnormalities can persist for months. However, little is known about long-term recovery.

"This is the first study to comprehensively look at a large population of infected persons to study the long-term effects of West Nile virus," said study author Mark Loeb, MD, MSc, Professor, Pathology and Molecular Medicine, Michael G. DeGroote School of Medicine, McMaster University, Ontario, Canada. "We found that both physical and mental functions, as well as mood and fatigue, seemed to return to normal in about one year."

Researchers followed 156 patients between 2003 and 2007 to record patterns of physical and mental effects of West Nile virus infection. Researchers anticipated greater severity and a longer course of depression and fatigue in participants with neurological problems. However, they found symptoms and recovery times to be similar to those in participants without neurological consequences of infection. Pre-existing health conditions were an important factor in long-term prognosis. Patients who were healthy at the time of infection returned to normal health more quickly on average than those who had pre-existing conditions.

Researchers say the data might help patients infected with West Nile virus and their health care providers know the expected rate of recovery of physical and mental functioning, fatigue, and depression.

Source: American College of Physicians

Explore further: Osteoporosis screening guidelines miss many younger post-menopausal women

add to favorites email to friend print save as pdf

Related Stories

Amphibians being wiped out by emerging viruses

Oct 16, 2014

Scientists tracing the real-time impact of viruses in the wild have found that entire amphibian communities are being killed off by closely related viruses introduced to mountainous areas of northern Spain.

Certain compounds stimulate mosquito taste receptors

Aug 05, 2014

Mosquitoes not only have a sense of smell for certain insect repellents, but they also have a sense of taste for these chemicals, according to U.S. Department of Agriculture (USDA) scientists.

Recommended for you

WHO: Ebola vaccine trials in W. Africa in January

8 hours ago

Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January as long as they are deemed safe, a top World Health Organization official ...

Ebola cases rise sharply in western Sierra Leone

8 hours ago

After emerging months ago in eastern Sierra Leone, Ebola is now hitting the western edges of the country where the capital is located with dozens of people falling sick each day, the government said Tuesday. So many people ...

User comments : 0