Explanation:
Haemophilia is a congenital disease. Congenital diseases are those that are present from birth and are usually inherited from one or both parents. Haemophilia is a hereditary disorder that affects the blood's ability to clot. It is caused by a genetic mutation that results in a deficiency or absence of certain clotting factors in the blood.

Causes of Haemophilia:
Haemophilia is caused by a mutation in one of the genes responsible for producing clotting factors. There are two main types of haemophilia:
1. Haemophilia A: This type is caused by a deficiency or absence of clotting factor VIII.
2. Haemophilia B: This type is caused by a deficiency or absence of clotting factor IX.

Characteristics of Haemophilia:
1. Bleeding: Haemophilia is characterized by prolonged bleeding, both internal and external. Even a minor cut or injury can result in prolonged bleeding.
2. Spontaneous Bleeding: People with haemophilia may experience spontaneous bleeding without any apparent cause. This can occur in joints, muscles, or other internal organs.
3. Joint Damage: Repeated bleeding into joints can cause damage and lead to chronic pain and limited mobility.
4. Severity: The severity of haemophilia can vary from mild to severe, depending on the level of clotting factor present in the blood.

Treatment and Management:
There is currently no cure for haemophilia, but it can be managed through various treatments and precautions. Treatment options include:
1. Replacement Therapy: Clotting factors are infused into the bloodstream to replace the deficient or missing clotting factor.
2. Medications: Certain medications can help stimulate the production of clotting factors in the body.
3. Physical Therapy: Physical therapy can help manage joint damage and improve mobility.
4. Preventive Measures: People with haemophilia should take precautions to prevent injuries that could lead to bleeding, such as wearing protective gear during physical activities.

Conclusion:
Haemophilia is a congenital disease that affects the blood's ability to clot. It is caused by a genetic mutation and is characterized by prolonged and spontaneous bleeding. Although there is no cure for haemophilia, it can be managed through various treatments and precautions.