How Yolanda Foster, Bella Hadid, Anwar Hadid All Have Lyme Disease

Yolanda Foster, who has spoken candidly about her struggle with Lyme disease, revealed Thursday that two of her children have were also diagnosed with the disease in 2012.

“Watching my babies struggle in silence to support me in my journey struck the deepest core of hopelessness inside of me,” Foster, 51, said of daughter Bella Hadid, 18, and son Anwar Hadid, 16, at the Global Lyme Alliance inaugural gala.

PEOPLE caught up with Dr. Raphael Kellman, the founder of the Kellman Center for Integrative and Functional Medicine who has not treated the stars, to find out more about Lyme disease and how it’s possible for several members of the same Real Housewives of Beverly Hills family all to be diagnosed with chronic Lyme disease, for which there is no standard treatment.

How likely is it that three members of one family all have chronic Lyme disease?
It’s not uncommon that a few members of a family have Lyme disease. … But it’s not genetic, it’s because they share the same environment.

A major cause could be imbalances in the billions of gut bacteria that we call the microbiome, those bacteria that are inside of our gut that outnumber us 10 to one and keep us healthy. It’s not uncommon for the microbiome to be unhealthy, and if the microbiome is unhealthy in one member of the family, it’s likely that it’s unhealthy in another member of the family. Each home has its own particular microbiome. … We tend to eat the same foods as other members of the family and experience similar stressors, which all contributes to changes in the microbiome.

Additionally, if someone develops chronic lyme or any chronic infection, typically there are other health issues that they have that they weren’t aware of. … These issues could be thyroid-related, which is a very big problem – it’s not uncommon if somebody develops Lyme disease and they had low thyroid in the past. Low thyroid occurs due to factors like immunological issues, gut issues, microbiome imbalances, environmental toxins. However, there’s also a genetic susceptibility as well, so perhaps a few members of the family also have low thyroid that maybe wasn’t picked up.

How is Lyme disease transmitted?
It’s not as certain as scientists used to think – that it’s transmitted only through ticks. There may be other methods, unfortunately, though not well known, of transmission of this disease. We don’t really know for certain that this is the only way it’s transmitted.

What are the symptoms of Lyme Disease?
Fatigue, but the fatigue could come and go. It could be post-exertional fatigue or fatigue they have one day and then the next day they feel somewhat better. Typically, Lyme disease is associated with a brain fog, headaches, difficulty concentrating … muscle and joint pain, tingling and numbness, neck pain, sometimes palpitations, different types of neurological symptoms. … Anxiety is one of the symptoms as well, and sometimes the anxiety can be debilitating and can even present as panic attacks.

But typically, the symptoms can wax and wane: One day the joint pain is here, and then the next day it’s somewhere else – it’s migratory. The tingling and numbness and the strange types of neurological symptoms, like a sense of electrical currents in them, can change from day to day.

RELATED: Avril Lavigne Suffers from Lyme Disease: Things to Know about the Illness

What makes it so hard for doctors to diagnose Lyme disease?

The presenting symptoms typically baffle the common doctor because of the uncommon types of symptoms, the way they’re presented and the wide constellation of symptoms … And unfortunately, because it’s not common and because lab tests frequently miss the problem, many of these patients just suffer in silence … Because it’s associated with so many symptoms that can come and go, that present in uncommon ways and that are frequently difficult to describe, it sometimes leaves patients speechless, which is another reason why so many of these patients are not being diagnosed properly and are not being treated. The most common phrases that I hear from so many patients with Lyme disease are, “I just feel like I’m dying,” and, “I can’t explain what I’m feeling.”

Additionally, [Lyme disease] is sometimes associated with personality changes: a sense of derealization, that they’re not really in their body. When people start speaking like this, with atypical presentations of symptoms, it tends to baffle doctors and one of the unfortunate responses is that it’s all in their head, they’re under a lot of stress, they need an antidepressant or an anti-anxiety medication.

How are celebrities like Avril Lavigne and Yolanda Foster helping those suffering from Lyme disease by sharing their own struggles with the illness?
It will give people more confidence not to live and settle with their symptoms and live their lives like that, to perhaps be tested again or to go to doctors who realize it’s a clinical diagnosis. You have to make the diagnosis not by blood testing, but by the clinical presentation and other biomarkers and footprints.

People now are more aware that Lyme disease is a very common problem, that it’s not just a small segment of the population that is suffering from this. It’s really much more widespread than anybody ever imagined. Many, many more people are suffering from Lyme disease than the statistics show, so i think that now when people know if they have these symptoms, they’re more likely to go to the doctor, they’re more likely to pursue this diagnosis and to be tested properly, and then if nothing helps them and they still have these symptoms, they understand that the test may come out negative and that they have to find the doctor who understands that it has to be diagnosed clinically.