Yolanda Foster on Bella Hadid’s Struggle With Lyme Disease

Photo: Instagram/bellahadid

Real Housewives of Beverly Hills star and Lyme disease sufferer Yolanda Foster surprised fans in October when she announced that two of her children are also battling the disease.

Foster, 52, has openly talked about the health battles her daughter Bella Hadid, 19, and son, Anwar Hadid, 16, have fought and even posted photos of the medication they’re taking on Instagram.

On Tuesday, Foster posted a photo on Instagram from 2015 that shows Bella lying in bed with an IV in her arm. “Watching my brave babies suffer in silence in order to support me in my journey has struck the deepest core of hopelessness inside of me,” Foster captioned the photo. “It is because of them that I continue to fight relentlessly. … I will not allow them to live a life of pain and suffering. … I will prevail and walk to the end of the earth to find a cure for them and millions of others debilitated by this invisible disease!!!! We all deserve to live a healthy life, don’t you think?”

Photo: Yolanda Foster/Instagram

Lyme disease is a tick-borne illness caused by the bacterium Borrelia burgdorferi. Approximately 30,000 new cases of the disease are reported to the Centers for Disease Control and Prevention each year.

Related: Lyme Disease Ticks Spread to Half of All U.S. Counties

But the disease isn’t contagious, and Foster’s children didn’t inherit Lyme disease from their mother. So how did Bella and Anwar end up with the disease too?

Rick Watkins, MD, an infectious disease specialist at Cleveland Clinic Akron General Medical Center, tells Yahoo Health that they simply could have had the same exposure to the ticks that cause Lyme disease. Foster’s family’s situation is “rare,” says Watkins, but it does happen. For example, a family may go camping together and be exposed to Lyme-infected ticks or live on a wooded property where the ticks reside.

Related: Why Is It So Hard to Get a Lyme Disease Diagnosis?

But aside from environmental factors, certain families are not prone to developing Lyme disease. “As far as we know, there is no genetic predisposition,” Watkins says. “Anyone could get it.”

Unfortunately, Bella’s youth isn’t a factor in her ability to fight the disease. According to Watkins, younger people can contract Lyme disease and suffer just as much as older people.

Related: How Did 3 Members of This Family Contract Lyme Disease?

As for the IV in Bella’s arm, Watkins says it’s an indicator that her Lyme disease is affecting her central nervous system. “It usually means the patient has had Lyme disease longer,” he says.

Foster wrote in a blog post on Tuesday that she thinks her family contracted Lyme disease while living on their horse ranch in Santa Barbara, Calif., where they spent a lot of time outdoors.

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