While doing countless hours of research on CVID, I am continually shocked at the amount of incorrect information I come across regarding the disorder. In fact, even some of the most reputable medical organizations in the United States have factually incorrect and/or incomplete information on their websites. That’s why I’ve compiled a list of CVID FAQS to help you and your loved ones access reliable information.

1. What is Primary Immunodeficiency (PI)? I’ve never even heard of that!

Per the Immune Deficiency Foundation Website, here is their official explanation of PI:

Primary immunodeficiency diseases are a group of more than 350 rare, chronic disorders in which part of the body’s immune system is missing or functions improperly. While not contagious, these diseases are caused by hereditary or genetic defects, and, although some disorders present at birth or in early childhood, the disorders can affect anyone, regardless of age or gender. Some affect a single part of the immune system; others may affect one or more components of the system. And while the diseases may differ, they all share one common feature: each results from a defect in one of the functions of the body’s normal immune system.

Because one of the most important functions of the normal immune system is to protect us against infection, patients with PI commonly have an increased susceptibility to infection. The infections may be in the skin, the sinuses, the throat, the ears, the lungs, the brain or spinal cord, or in the urinary or intestinal tracts, and the increased vulnerability to infection may include repeated infections, infections that won’t clear up or unusually severe infections. People with PI live their entire lives more susceptible to infections–enduring recurrent health problems and often developing serious and debilitating illnesses. Fortunately, with proper medical care, many patients live full and independent lives.

2. What is Common Variable Immunodeficiency Disorder (CVID)?

This is yet another one of the most well-loved CVID FAQS!


CVID is complex and so is explaining it! So, I’m going to defer to Wikipedia’s definition which in my opinion is the easiest to understand for those non-medical/science folks (like me!):

Common variable immunodeficiency (CVID) is an immune disorder characterized by recurrent infections and low antibody levels, specifically in immunoglobulin (Ig) types IgG, IgM and IgA.[1] Generally symptoms include high susceptibility to foreign invaders, chronic lung disease, and inflammation and infection of the gastrointestinal tract.[1] However, symptoms vary greatly between people. CVID is a lifelong disease…Treatment options are limited, and usually include lifelong immunoglobulin replacement therapy.[4] This therapy is thought to help reduce bacterial infections. This treatment alone is not wholly effective, and many people still experience other symptoms like lung disease and noninfectious inflammatory symptoms.

*Note from Susan Alynne: although it seems to me CVID and the immune system in general is in its early stages of full understanding by the medical community, the cause is thought to be genetically-related. It is so in my case. Dr. K recently told me my 13-year-old son has CVID and my 9-year-old son has IgG Subclass Deficiency.

3. Why are CVID patients called Zebras?

Yes, zebras are, well, the zebras that are black and white striped that you see at the zoo. However, ZEBRA, is the term (description even) that has become the symbol, dare I say the “mantra” of those patients who have been diagnosed with a Primary Immunodeficiency. Here’s the official explanation of how we came to be called Zebras:

Per the Ehlers-Danlos Support UK website:

When you hear the sound of hooves, think horses, not zebras.”

This phrase is taught to medical students throughout their training.

In medicine, the term “zebra” is used in reference to a rare disease or condition.  Doctors are taught to assume that the simplest explanation is usually correct to avoid patients being misdiagnosed with rare illnesses. Doctors learn to expect common conditions.

But many medical professionals seem to forget that “zebras” DO exist and so getting a diagnosis and treatment can be more difficult for sufferers of rare conditions. Ehlers-Danlos syndrome is considered a rare condition and so EDS sufferers are known as medical zebras.  This identity has now been adopted across the world through social media to help bring our community together.

I have compiled a list of resources that have helped me so check it out!