April 22-29 is World PI Week – a week to raise awareness about primary immunodeficiency diseases. There are more than 450 types and patients are vulnerable to serious infections.
![Infographic about primary immunodeficiency, including facts such as there are 450+ forms of PI and an estimated 10 million worldwide living with the condition.](https://www.csl.com/-/media/shared/vita-2023/april-24---csl-pi-infographic.jpg?h=3399&iar=0&w=1600&hash=B9D120C9F03E63F82687A679E5058EAE)
It’s World PI Week. Patients who have this immune system problem often face a long road to diagnosis.
April 22-29 is World PI Week – a week to raise awareness about primary immunodeficiency diseases. There are more than 450 types and patients are vulnerable to serious infections.