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PI Week – April 22-29, 2025

PI Week is observed every year from April 22 to April 29. It is a global initiative that aims to increase awareness and improve the early diagnosis and treatment of primary immunodeficiencies (PI). Did you know that PI is not a single disease? Yes, primary immunodeficiencies are a group of more than 400 rare, chronic disorders in which part of the body’s immune system is missing or malfunctioning. A lot of people suffer from PI every year worldwide, and many lose their lives or their loved ones’ lives to this disease too. Here is all you need to know about the history and significance of PI Week.

History of PI Week

PI Week was founded to help raise awareness about primary immunodeficiencies and improve the lives of patients suffering from them. Primary immunodeficiencies are usually caused by hereditary genetic defects and can affect anyone. It means that regardless of age, gender, ethnicity, and environment, you can be affected by PI. All the different PIs share one common feature: disruption of the body’s immune system. PI weakens the immune system and increases the body’s susceptibility to infection. The infections may be in the skin, sinuses, throat, ears, lungs, brain, spinal cord, urinary tract, or intestinal tract. Symptoms of PI include frequent pneumonia, inflammation, blood disorders, digestive problems, delayed growth and development, and autoimmune disorders.

Living with PI is difficult for patients with PI as they commonly also have recurring infections that won’t go away or unusually severe infections. According to health experts, over six million people across the globe suffer from PI, and 70% to 90% of those with PI are still undiagnosed. Therefore, early diagnosis is crucial because it contributes significantly to improving the quality of life and care for people suffering from PI.

The first step in diagnosing PI is usually blood testing, where doctors can evaluate the patient’s immune system through additional tests, physical examinations, and reviews of the medical and family histories of the patient. As far as the treatment goes, immunoglobulin therapies are essential, life-long treatments for the majority of people with primary immunodeficiency.

PI Week timeline

The First PI Disease

Ogden Bruton discovers the first PI, X-linked agammaglobulinemia.

The Count Hits 50

The World Health Organization (WHO) has identified 50 PI diseases since the identification of the first one.

The Birth of World PI Week

Organizations all across the world are coming together to promote the cause during the first World PI Week.

The Increased Awareness

People across the world become more aware of PIs and support World PI Week.

PI Week FAQs

What is secondary immunodeficiency?

While primary immunodeficiencies are the result of genetic defects, secondary immunodeficiencies are caused by environmental factors, such as HIV/AIDS.

Can primary immunodeficiency be cured?

Some treatments can keep children healthy and active for many years in the case of some primary immunodeficiency diseases (PIDs). However, none of them is capable of curing PID. Hematopoietic stem cell transplantation or gene therapy is the only recognized cure.

What are the signs of a weak immune system?

Signs of a weak immune system include frequent colds, infections, digestive problems, delayed wound healing, fatigue, organ problems, delayed growth, and blood disorders.

How to Observe PI Week

  1. Spread the word

    One of the simplest things you can do to participate in World PI Week is by spreading the word about PI. You can help raise awareness of PI within your community as well as other communities.

  2. Donate plasma

    By donating your plasma, you help ensure that immunoglobulins and other plasma-derived medicinal products are available for the PI patients as well as for others who need them. You can also invite eligible donors from your friends.

  3. Share your story

    You can carry out an activity with your friends, like fundraising for PI patients. Following that, you can visit their community and share photos or videos on social media with the hashtags #WorldPIWeek or #HealthAwareness.

5 Must-Know Facts About PIs

  1. They are not related to Aids

    Contrary to popular opinion, PI is not related to Aids, which is caused by the HIV virus.

  2. They can appear in adulthood too

    While many PI appear in childhood, some emerge for the first time in adulthood.

  3. They thrive where stress is abundant

    You can keep stress in check with massage, yoga, or hobbies to strengthen your immune system.

  4. Genetic counseling can help

    If you have a type of primary immune deficiency disorder, genetic counseling can help.

  5. Sleeping is a preventative measure

    Getting enough sleep can help you prevent infections caused by a weak immune system.

Why PI Week is Important

  1. Health is always important

    This week will help policymakers, health institutions, and people, in general, understand the importance of early diagnosis and treatment for PI. It will also encourage them to pay attention to other health issues that require the same awareness

  2. It is a global movement

    World PI Week is an opportunity to join others from around the world by signing your name to the Global PI Call to Action, asking governments to understand and support it. This will have a big impact.

  3. This day supports advocacy

    By celebrating World PI Week and raising your voice for better treatment and diagnosis of the disease, you are also helping drive change in policy to benefit patients with PI. Every small action counts.

PI Week dates

2025April 22Tuesday
2026April 22Wednesday
2027April 22Thursday
2028April 22Saturday
2029April 22Sunday

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