What is SCID?

Severe combined immunodeficiency (SCID) is the name given to a group of rare, inherited disorders that cause major abnormalities of the immune system.

SCID is caused by a mutation in a child’s genetic make-up. It means specialised white blood cells, known as lymphocytes, are missing or not functioning properly.

Signs usually occur within the first three to six months. The baby is likely to suffer infections more frequently than other infants and ordinary coughs and colds will seem more severe and last longer than would be expected, requiring repeated and prolonged treatment.

Environmental germs that don’t trouble healthy individuals can cause serious and lifethreatening illness in a child with SCID.

In most cases, haematopoietic stem cell transplantation – where cells from healthy bone marrow replace a patient’s faulty immune system – offers the only long-term cure.