West Nile cases rise in L.A. County

17 people have died, officials say, and heat could make the virus more likely to spread.

Amid a heat wave that could make West Nile virus more likely to spread, the number of people infected with the disease in Los Angeles County continued to climb this week.

At least 230 people in L.A. County have fallen sick with West Nile this year, and 17 of them have died, health officials said Friday. The number of people infected is already the third-highest ever in the county, according to health officials — and the season has yet to end.

“We typically see cases until the end of November,” said Dr. Aiman Halai, head of the vector-borne disease unit at the Los Angeles County Department of Public Health. “West Nile virus is a risk in all areas of the county.”

Though most people who get West Nile don’t have any symptoms, one out of every 150 people infected develops serious problems that can include meningitis (swelling of the brain), vision loss, coma and weeks-long or even permanent paralysis.

People 50 and older or whose immune systems are compromised are most likely to suffer from these severe consequences, but every year a few younger people also experience them, experts say.

Jill Cordes, who lives in Silver Lake, first became concerned about the virus when a kindergarten teacher at Ivanhoe Elementary became paralyzed after she was infected last year. Cordes’ 5-year-old and 7year-old children both attend the school.

This year, two people who live within blocks of Cordes have fallen seriously ill with the virus. She bought DEET bug spray to put on her kids if they want to leave the house near dawn or at night, when the mosquitoes are out.

“I basically don’t want them outside if they’re not completely slathered in

DEET,” Cordes said. “I think it’s really scary, and I don’t think people know that we’re at such an epidemic level.”

Across California, more than 430 people have fallen sick with West Nile virus, and 24 have died this year.

Dr. Benjamin Schwartz, deputy director of the L.A. County Public Health Department’s acute communicable disease program, said cities that already have had cases are likely to have additional cases in the following month.

In L.A. County, Glendale, Los Angeles and Burbank have had the most cases so far, along with neighborhoods across the San Gabriel and San Fernando valleys.

“If you live in one of those cities, it’s a warning,” Schwartz said.

The hotter the weather, the faster the West Nile virus replicates within mosquitoes, making it more likely to be passed on to humans, said Levy Sun, spokesman for the Greater Los Angeles Vector Control District.

Sun said mosquitoes sometimes can’t survive very hot and dry weather such as Southern California experienced this week.

But when vector control workers have recently checked traps to see whether mosquitoes were affected, “we’re not seeing the die-off we’re hoping for,” he said.

Until it gets too cold for the mosquitoes, West Nile season won’t end, Sun said.

soumya.karlamangla@latimes.com Twitter: @skarlamangla