West Nile Virus Infections Went Up in 2010

Official statistics from the US Centers for Disease Control and Prevention (CDC) indicate that the total number of West Nile virus (WNV) infections went up in 2010, when compared to previous years.

The data covers the United States exclusively, and indicate that 1,021 people got infected by the dangerous viral agent last year. The severe form of the infection – which occurs when the virus enters the patients' brains – occurred in 629 of these cases.

Of the 57 people who died following infection, 54 had the neuroinvasive form of the condition. In total, 718 patients were hospitalized for treatment. When the CDC compared these results with the ones for 2009, it determined that 62 percent more cases were recorded last year.

The experts then focused their attention on neuroinvasive cases of WNV infection. They determined that four American states concentrated more than 50 percent of all those who were diagnosed with this form of the disease, My Health News Daily reports.

Arizona led the way in this chart with 107 cases, followed at some distance by New York with 89 cases, Texas with 77 and California with 72. All remaining cases were split between other states. Interestingly, the team determined that 88 percent of all new infections occurred in July, August and September.

CDC specialists say that there is a large number of factors influencing the number of WNV infection cases. These include interactions between viral agent carrier (usually insects), environmental factors, human behavior, as well as medical diagnostics and reporting practices.

Such widely-different aspects cannot be correlated in a model that would predict with any degree of certainty where and when WNV infection cases would spiral. In other words, there is no way of detecting how the viral agent will spread.

Researchers at the Mayo Clinic say that the most common symptoms of such infections include fever and headaches, as well as generalized body aches and fatigue. High fever, stiff neck, disorientation and sudden weakness the limbs are associated with severe forms of the disease.

The CDC is so interested in the West Nile virus because it is a relatively new addition to the panoply of infectious agents that act in the United States. The organism was first identified in the Western Hemisphere back in 1999.

Since then, statistics show, it has become the leading cause of neuroinvasive diseases caused by mosquitoes and ticks. People who want to decrease their risk of infection should use mosquito repellent and wear long-sleeved shirts as much as possible.