Have you heard the story of the “Bubble Boy”? This isn’t a sci-fi story—it tells the real-life experience of a boy who lived in a bubble for his own safety because he had severe combined immunodeficiency (SCID). Tragically, he later passed away after developing a type of cancer. But does this mean all babies diagnosed with SCID must live in a bubble?

Fortunately, no. Advances in medicine, technology, and science now allow babies with severe combined immunodeficiency to live nearly normal lives without confining them to a bubble. So, what exactly is SCID or bubble boy disease? How common is it, and are children at risk? Read on to learn everything you need to know about severe combined immunodeficiency.

In This Article

• The Story of the Bubble Boy
• What is Severe Combined Immunodeficiency?
• How Does Severe Combined Immunodeficiency Occur?
• How Does SCID Impact the Health of a Baby?
• Causes of Severe Combined Immunodeficiency in Babies
• Signs and Symptoms of Bubble Boy Disease
• Diagnosis of Severe Combined Immunodeficiency in Babies
• How to Prevent Severe Combined Immunodeficiency?
• Treatment Options Available For SCID in Babies
• Precautions to Help a Child With SCID
• When to Seek a Doctor’s Help?

The Story of the Bubble Boy

David Vetter, a boy born in 1971, was diagnosed with Severe Combined Immunodeficiency (SCID). This little boy lived his short life in a sterile plastic bubble to protect him from various pathogens and infections in the environment. Since his brother died in infancy due to SCID, the doctors placed him inside a sterile bubble within seconds after birth, once they confirmed he also had SCID. Once a bone marrow transplant became available, they tried to give him a transplant from his sister. But he later died contracting a type of cancer.

What is Severe Combined Immunodeficiency?

Severe Combined Immunodeficiency, more popularly known as SCID, is a rare disorder. SCID is often called “bubble boy disease”. It is a group of rare syndromes that a person genetically inherits. It can lead to very little or no immunity, resulting in multiple infections and diseases, which may not affect a person otherwise. What can be a simple or mild infection in a healthy person can be a life-threatening infection for a baby with SCID.

The immune system is the body’s protective shield, consisting of white blood cells. These white blood cells are what protect the body from foreign invaders such as fungi, bacteria, and viruses.

Lymphocytes – a type of white blood cell become the T-cells, B-cells, and the natural killer cells. Each of these three cells is responsible for protecting the body from infections. T-cells are the most important of all as they fend the body against all kinds of infections.

When a foreign particle enters the body, the immune system responds by producing more white blood cells to fight off the infection and keep the body safe. When this immune system is very weak or just absent, the person becomes vulnerable to all types of infections and diseases.

[Read: 10 Warning Signs of Primary Immune Deficiency in Children]

How Does Severe Combined Immunodeficiency Occur?

SCID is an inherited disorder in which babies do not produce T-cells from birth. Without T-cells, other cells in the body — such as B-cells—cannot function properly. When multiple types of these cells malfunction, the body develops ‘combined’ immunodeficiency.

Today, hospitals in the US and European countries screen all newborns for SCID. Detecting SCID at the time of birth helps the doctors keep the baby safe and decide on an early treatment option. The earlier the detection of SCID, the higher the chances of a successful bone marrow transplant, which in turn can improve immunity. However, we do not have such screening facilities or programs in India at the moment.

How Does SCID Impact the Health of a Baby?

A newborn baby is born with a certain amount of protection. The antibodies from the mother protect the baby from various infections in the environment. This protection lasts a few months, during which the baby’s immune system starts developing.

When the immune system does not develop, the body does not have a protective shield. When the antibodies derived from the mother’s body run out, the baby becomes susceptible to various infections.

There are many pathogens in the environment that can make all of us sick. However, for a person with bubble boy disease, the impact is much more. As mentioned earlier, a virus or bacteria that might have a mild impact on a healthy individual might have a severe and long-lasting impact on a baby with SCID. Similarly, an organism that normally would have close to no impact on a healthy individual, will affect and cause serious health issues in a baby with SCID.

Causes of Severe Combined Immunodeficiency in Babies

SCID is an inherited disorder. There are about 20 different types of SCID and these are all caused due to various genetic defects. Two of the most common SCIDs are X-linked SCID and ADA SCID.

1. X-Linked SCID

A defect in the X-chromosome can lead to SCID. Since the male has only one X chromosome unlike the female who has 2 X chromosomes, this type of SCID affects only boys. A female with a defective X chromosome will become a carrier without suffering from a disorder themselves. When this defective X chromosome is passed on to a male child, the child’s chances of a disorder increase.

2. ADA SCID

ADA SCID is the second most common type of SCID, which is responsible for almost 15% of the SCID cases reported. This type of SCID is caused due to a lack of ADA (Adenosine Deaminase Deficiency). ADA helps convert the harmful deoxyadenosine into a harmless molecule. When the ADA is not available to perform this role, harmful molecules build up and kill the immune system.

These can not only result in a weak immune system that can lead to various infections, but can also cause neurological problems like hearing and visual impairment, cognitive impairment, and movement disorders. This type of SCID can affect both boys and girls.

What is Severe Combined Immunodeficiency?

Early detection of this disorder can help protect the baby and provide them with a better quality of living. With effective treatment, many can lead almost normal lives. A successful bone marrow transplant can even enable them to live a “normal” life.

Here are a few signs and symptoms that can indicate bubble boy disease in the child. If a baby shows any of these symptoms within the first year of their life, they should definitely be checked for SCID and other related disorders.

• Pneumonia – 2 or more occasions
• Ear infections – multiple episodes of ear discharge
• Inability to gain weight
• Infections that persist for more than 2 months and do not resolve with the usual antibiotics
• Affected growth
• Multiple infections that require antibiotics through IV
• Thrush in the mouth or throat that does not go away
• Infections that affect the lungs or the liver
• Recurrent infections that require strong medications or treatments
• Diarrhea that does not respond to antibiotics

Diagnosis of Severe Combined Immunodeficiency in Babies

Diagnosing Severe Combined Immunodeficiency is not an easy task. Unfortunately, many pediatricians and most family physicians are not even aware of the occurrence of such a disease in young children! These babies often receive antibiotics on several occasions and eventually die of a serious infection. There is not much awareness regarding these diseases in the medical fraternity, and Pediatric Immunologists are striving hard to ensure Pediatricians think of these diseases when they come across sick children. Also, if a child has a family history of SCID or the death of a sibling at a young age, such babies must be immediately tested for the presence of SCID.

Timely diagnosis of this disorder can make a lot of difference to the child’s quality of life. Not only can the doctors prescribe suitable treatments, but they can also advise parents on how to be careful. The medical professionals can help the family understand the severity of the disorder and help them adapt to a different lifestyle.

Steps in Diagnosing Severe Combined Immunodeficiency

When a baby is sick more often and takes more time than usual to recover from an illness, the doctor will suspect an issue with the immune system. The following tests/ steps can be taken to confirm a bubble boy disease diagnosis:

• The doctor will ask for a complete medical history to understand and determine if any of the parents has a defective gene
• A thorough physical examination will help determine if the baby’s growth is on par with the average growth rate
• Blood tests will help determine the blood count – a number of T-cells and B-cells need to be checked if they are at the required level.

How to Prevent Severe Combined Immunodeficiency?

Now, can you “prevent” SCID? No, unfortunately, you cannot do that in the first pregnancy. Parents of children with SCID are healthy and do not have any health issues. Hence, it is practically impossible to diagnose this condition in the first baby before he/she is born. However, if a family has a child with SCID, one can perform in-utero testing in the next pregnancy, and this would help confirm the diagnosis even while the baby is in the womb of the mother.

1. In-Utero Diagnosis

If parents with a defective gene (carriers) have already had a child with SCID, they need to inform the doctor of the same during their next pregnancy. The doctor will check for SCID in utero. This is not a regular test. It is not taken unless there has been a sibling with SCID. It is a rare procedure. By performing tests like chorionic villous sampling (CVS) or amniocentesis, the doctors can determine if the baby is affected in utero.

If the fetus is affected, the family may decide to discontinue the pregnancy. If they continue the pregnancy in such a situation, an early bone marrow transplant can be performed after birth. And if a bone marrow transplant is done within the first 3 months, the chances of leading a regular, normal life are very high.

2. Early Detection

If a newborn baby is diagnosed with SCID, the doctors can start early treatment and help the baby to a safer lifestyle, thereby keeping the baby safer. They can also do a bone marrow transplant as soon as possible. They can help them lead a good quality of life, but this does not come without compromises.

SCID is a serious medical condition. Without treatment, this condition is 100% fatal, and all the babies die within the first 2 years of life!

Treatment Options Available For SCID in Babies

The most effective treatment available for SCID is a bone marrow transplant. Replacing the affected bone marrow with a healthy one to produce the required number of white blood cells is the only option today to treat this disease.

We need an HLA-matched donor to perform a bone marrow transplant in a baby with bubble baby disease. A perfect match for a bone marrow transplant would be a healthy sibling. The chances of this are small. In case a matched sibling is not available, a matched donor from the registry or a half-matched parent will be the donor for the child diagnosed with SCID.

In 1990, successful gene therapy gave some hope to SCID patients. However, it was halted due to complications that arose after the therapy in some children. Research is underway to find more successful methods of gene therapy.

While preparing for a transplant, it is essential to protect the baby from any further infections. These are some treatment options a doctor will follow for SCID:

1. Antibody Infusion

In order to prevent further complications from SCID, the doctor will try to substitute the missing antibodies in the baby’s immune system. SCID causes the B-cells and T-cells to malfunction, thereby causing low or totally absent antibodies. This paves the way for all other infections, which in turn can cause serious damage to various parts of the body. In order to prevent this, the doctor will infuse antibodies (intravenous immunoglobulin – IVIG) into the baby.

These antibodies can be infused through an IV. They take up the role of protecting the body from various infections. Since the body is not producing the required antibodies, these infusions will be frequent. The frequency depends on how severe the SCID is and how low the antibody production is in the body.

2. Treat Infections

Treat the current infection to ensure it does not affect other parts of the body. For example, if the baby is suffering from recurrent respiratory issues, the doctor will prescribe antibiotics and other medications to control the cough.

3. Protect Organs

If an infection damages an organ, doctors treat it to improve its function and prevent further harm. For example, if severe respiratory issues affect the lungs, treatment protects and preserves the lungs from additional damage.

Eventually, these babies must receive a bone marrow transplant to survive. Without a transplant, all other treatments are futile.

Precautions to Help a Child With SCID

Some of the precautions you will have to follow to help a child with SCID are:

• Do not give any live vaccines.
• Sterilize their environment constantly to prevent infection spreading and germs from thriving.
• Do not let them touch or interact with others with infections.
• Consult a doctor and start medication immediately, in case of an infection – even if it is a small common cold.
• Include healthy and clean food in their regular diet.
• Practice more hygiene around them.
• Take various precautions to avoid any kind of food or water contamination.
• Keep them away from highly infectious environments, such as parks or other places where children usually gather.
• Keeping them away from highly crowded areas like malls, movie theatres, play areas, etc.

A diagnosis of bubble boy disease will require the child and the family to make some serious lifestyle changes. Only that can help improve the quality and length of the child’s life. This does not mean they need to go into a bubble, but a bubble-like environment has to be created for them to keep them safe. It is not completely in their hands. However, once the baby undergoes a bone marrow transplant and their immune system starts functioning, they can lead a normal life.

When to Seek a Doctor’s Help?

It is very natural for a parent to shrug off recurrent colds, coughs, and even fever in small babies. Their immune system is developing and is just getting stronger as they grow. So, they are susceptible to multiple infections in the first few years of their lives.

When they start school, they fall sick very often. As the body gets introduced to new organisms, the immune system gets attacked and learns to fight back. But how long can you ignore these recurrent infections? When do you take a serious call on it?

It is always a better idea to consult your pediatrician every time your newborn or young baby falls sick. It may be tempting to self-medicate when your baby keeps getting that cold or when that ear infection does not subside even after the doctor’s prescribed dosage of medicine is over. Never do that! It is never a good idea to either hide symptoms from the doctor or take matters into your own hands.

Warning Signs to Look Out For the Possibility of SCID

As a parent, you may wonder when to check your child for bubble boy disease (Severe Combined Immunodeficiency, SCID). Watch for these warning signs:

• The child has a cold or cough that doesn’t improve despite antibiotics and other medicines.
• Your child falls sick more often than their peers.
• Small infections affect your child more severely.
• The child has recurring or persistent ear infections despite treatment.
• Your baby develops oral thrush that keeps coming back.
• The child experiences diarrhea that doesn’t respond to medications.
• Your child is smaller or lighter than peers and isn’t gaining height or weight as expected.
• The family has a history of SCID, and your child falls sick frequently.

SCID is a complex disorder. Both the child and family must adopt new habits to reduce infection risks. Everyone in the household must practice good hygiene, as keeping the child in a sterile room alone does not prevent infections.

Caring for a child with SCID can exhaust parents mentally, emotionally, and physically. Seek support for both yourself and your child. Trying to manage everything alone can make the journey harder. Focus on keeping your child comfortable, healthy, and emotionally supported.

The good news is that timely bone marrow transplantation can completely cure SCID. With proper care, precautions, and medical intervention, children with this condition can lead healthy lives.