It was a baffling and – downright gross – discovery.

Just before Thanksgiving, Dan and Sandi Cuellar found lice living in 4-year-old daughter Alegria’s thick, long, dark brown hair – something they never expected, living in a million-dollar home in an exclusive Corona neighborhood.

“We live a privileged life,” Dan Cuellar said, “And for us to wake up one day and find lice, we thought, ‘What did we do? We’re not homeless. Our daughter takes a bath every day.’”

They would soon learn the head louse doesn’t discriminate.

“It really has nothing to do with how clean your hair is or your income bracket,” said Dale Clayton, a biology professor at the University of Utah and a parasite expert.

And the family learned the ancient parasite that was once ubiquitous is still quite active in the 21st century.

No one seems to know for sure how active lice are. For example, the U.S. Centers for Disease Control and Prevention says reliable figures aren’t available but estimates 6 million to 12 million infestations occur annually in the nation among children ages 3-11.

Health officials in Riverside and San Bernardino counties say they don’t keep statistics on outbreaks because there is no requirement to report them. They don’t know if infestations are on the uptick.“It is an age-old problem when people congregate closely together,” Claudia Doyle, a spokeswoman for the San Bernardino County Department of Public Health, wrote in an email. “There are no real health concerns with head lice except the ‘ick’ factor and a nuisance. Head lice are not known to carry disease.”

But some experts say infestations appear to be increasing.

“Just anecdotally, the problem clearly is worse than it was 20 years ago,” Clayton said.

EVOLVING RESISTANCE

It’s perhaps worse because the louse has evolved to the point that chemicals traditionally used to kill the bug often don’t work anymore.

John Marshall Clark, a professor of environmental toxicology and chemistry and an insecticide toxicologist at the University of Massachusets at Amherst, published with other researchers last year a study that found lice in 48 states had developed significant resistance to popular over-the-counter treatments.

Most treatments contain the same family of active ingredients based on natural pyrethrins or synthetic pyrethroids, according to the study published in the Journal of Medical Entomology in March 2016.

“These were brought on the market and they were very, very effective,” Clark said by phone.

A big problem, though, he said, is “we’ve used virtually one product.” And over time, lice adapted and mutated, and outbreaks have become difficult to control, he said.

Brad Mullens, a professor of entomology at UC Riverside, said it’s something that’s happened repeatedly with insecticides.

“If you pressure an animal hard enough, you’ll kill the susceptible individual,” Mullens said. “Then, before you know it, those resistant genes become more common.”

It doesn’t help that modern behavior among teens may lead to more outbreaks.

Clark said young children always have played in proximity, spreading lice by hugging and bumping against each other.

“Then all of the sudden we have this behavior of teens huddling together,” Clark said, referring to the soaring popularity of gathering for selfie group photos to post on social media.

He said he’s not aware of any study on the topic, but it’s a possibility.

What’s uncertain is whether groups huddle for selfies long enough for the bugs to travel from one strand of hair to another, he said.

‘TRAPEZE ARTISTS’

Lice aren’t the most gifted travelers.

“They don’t hop, jump or fly. They crawl,” said Scott Weiss, operator of lice removal clinics in Torrance and Los Alamitos. “But they only need one strand.

“Think of it as a circus with a trapeze artist trying to get from one side to the other,” Weiss said.

How lice landed on strands of 4-year-old Alegria’s lustrous hair, Dan Cuellar said he has no idea. He and his wife thought it came from a child at their daughter’s day care center, but no other case was reported there.

In any event, the Cuellars rushed to get treatment. Upon a doctor’s recommendation, the family drove to Los Alamitos to be treated Los Alamitos Lice Removal, one of the two clinics operated by Weiss.

So just before Thanksgiving, Cuellar said, Alegria and her mother received a comprehensive 5 step chemical free treatment process from Weiss that got Alegria lice free in about one hour.

LINING KIDS UP

If it is discovered a school-age child has lice, Inland districts urge parents to treat it but are generally less strict than they used to be.

Dan Evans, spokesman for the San Bernardino County superintendent of schools, said students typically are removed from the classroom. Parents receive information about treatment and students return the next day.

Cathy Owens, the Murrieta Valley Unified School District’s coordinator of health services, remembers when things were different. Up to 25 years ago, schools had “no-nits” policies, she said.

“They had to be nit-free in order to return to school,” Owens said.

Educators also reacted strongly and publicly when a child was found with lice.

“We would go to the classrooms and line the children up and check each head,” Owens said.

Today, she said, educators are discreet to avoid embarrassment, and hasten the child’s return to class to avoid hampering learning.

Dr. Shabnam Zargar, a pediatrician with UCR Health in Palm Springs, said children do not spread disease.

“It is not a health hazard,” Zargar said.

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