3 out of 9 human cases of West Nile virus in Texas have more severe form of the disease

AUSTIN (KXAN) — Three of the nine reported human cases of West Nile virus have had the more severe form of the disease, also known as West Nile neuroinvasive disease, according to the Texas Department of State Health Services (DSHS).

Symptoms of West Nile neuroinvasive disease include:

• headache
• high fever
• neck stiffness
• stupor
• disorientation
• coma
• tremors
• convulsions
• muscle weakness
• paralysis.

Treatment for patients with neuroinvasive West Nile virus, often involves hospitalization, intravenous fluids, respiratory support and prevention of secondary infections, according to the World Health Organization.

DSHS said 20% of infected people typically only develop a mild form of the disease, which is known as West Nile fever. The other 80% usually do not develop illness.

According to DSHS, only about one out of 150 people infected with West Nile virus will develop West Nile neuroinvasive disease, which may affect the brain and spinal cord.

“The incubation period of West Nile virus in humans is two to 14 days. Signs and symptoms of mild disease may last a few days. Signs and symptoms of severe disease may last several weeks or months, although neurological effects may be permanent. Rarely, death can occur,” DSHS said.

The Centers for Disease Control and Prevention said the fatality for those with the more severe disease was approximately 10%.