(CNN) -- Betty West knew that something was wrong when her husband Howard slept through a NASCAR race on television.
They had been married 65 years, and she knew he never, ever slept through NASCAR.
"All that day, I sat there and watched him, and I knew something was wrong with my husband," she said.
When he woke, he had trouble moving his arms and legs, so they went to the hospital. Doctors diagnosed dehydration, gave him fluids, and sent him home.
But Howard West wasn't himself anymore, his wife said. He lacked energy. He wasn't hungry. He got a fever.
A second trip to the hospital revealed that he had the West Nile virus.
"That's when I knew my husband was going to go," Betty West told CNN affiliate WRAL in North Carolina.
He got weaker and weaker, finally losing the ability to speak, before he died August 9.
"Just as easy as it could be. No struggles, just gave it up," Betty West said of the man she married when she was 17.
The United States is experiencing its biggest spike in the number of West Nile virus cases since 2004.
Howard West is one of at least 26 Americans, by official federal count, to have died in the outbreak of the disease carried by infected mosquitoes. His widow thinks he was probably bitten as he worked on the tomatoes in the garden he loved.
She's grateful that he didn't suffer or have to spend time in a nursing home at the end of his life.
"If you got to go, just get out of here quickly," Betty West said.
Suddenly, a widow after a lifetime with Howard, Betty is now ready to go, too, she says.
"I don't have a lot of desire to hang around here now," she said. "And I hope my children understand. You've been with someone 65 years and you go put them in the ground and a part of you goes in there, too."
Howard West lived and died in North Carolina, but Texas is the state hardest hit by the current outbreak.
Dallas Mayor Mike Rawlings declared Wednesday that the city is facing an emergency as the West Nile virus spreads, killing at least 16 people in Texas.
The Dallas declaration clears the way for aerial spraying to kill the infected mosquitoes that carry the disease.
There were 26 deaths and 693 cases in 32 states nationwide as of Tuesday evening, according to the U.S. Centers for Disease Control and Prevention. Spokesman Tom Skinner told CNN the agency is updating case counts once a week after it has analyzed reports. The next report on its website is set for August 21.
Dallas County was already under a state of emergency declared last week.
Judge Clay Jenkins declared the emergency Friday in his capacity as director of the county's Homeland Security and Emergency Management agency and instructed the department to file a local disaster declaration with the state.
Ground and aerial spraying will happen as weather allows.
"The insecticide is safe," Jenkins said. "The planes are quite sophisticated, and they get the spray to where it needs to go."
The Indiana State Department of Health announced Wednesday that state's first West Nile virus death this year. The death occurred in Vanderburgh County, said spokeswoman Amy Reel. She said she was not permitted to provide further details.
Six other cases have been reported across Indiana.
Louisiana health officials said the more serious form of the virus has seen its highest level since 2006. So far, six people have died from the virus in Louisiana this year.
In the United States, most infections occur between June and September, and peak in August, according to the CDC.
"It is not clear why we are seeing more activity than in recent years," CDC medical epidemiologist Marc Fischer said Friday. "Regardless of the reasons for the increase, people should be aware of the West Nile virus activity in their area and take action to protect themselves and their family."
Symptoms include fever, headache, body aches, joint pains, vomiting, diarrhea or rash.
"Less than 1% develop a serious neurologic illness such as encephalitis or meningitis (inflammation of the brain or surrounding tissues)," the CDC said.
Those at greater risk are people older than 50 and those with conditions such as cancer, diabetes and kidney disease, or with organ transplants.
There are no medications to treat the West Nile virus or vaccines to prevent infection. People with milder illnesses typically recover on their own, but those more seriously affected may need hospital care.
Health experts say prevention measures include avoiding mosquito bites, using insect repellant and getting rid of insect breeding sites.
CNN's Phil Gast, Joe Sutton, Michael Martinez, Caitlin Hagan and Carma Hassan contributed to this report.