Sickle Cell Anaemia
Following Thalassemia, another major genetic blood disorder that poses a significant public health challenge in India is Sickle Cell Anaemia (SCA). Because of its high prevalence among specific demographic groups, it is a critical topic for public health and tribal welfare administration.
Understanding Sickle Cell Anaemia
Sickle Cell Anaemia is an inherited genetic disorder that fundamentally alters the shape and function of Red Blood Cells (RBCs).
Normally, healthy red blood cells are round, smooth, and flexible, allowing them to glide easily through the body’s narrowest blood vessels to deliver oxygen. However, in a person with SCA, a genetic mutation causes the haemoglobin inside the RBCs to form abnormal, rigid strands. This forces the red blood cells to collapse into a rigid, crescent or “sickle” shape.
Because these sickle cells are inflexible and sticky, they frequently get trapped inside small blood vessels. This blocks the normal flow of blood, depriving downstream tissues and organs of oxygen. This blockage leads to severe complications, including excruciating pain (known as a pain crisis), high vulnerability to infections, severe anaemia, and gradual organ failure.
Genetics and Transmission
Like Thalassemia, Sickle Cell Anaemia is an autosomal recessive genetic disorder. Its transmission depends entirely on the genes passed from parents to children.
Sickle Cell Trait (SCT):
- A person who inherits only one copy of the mutated gene is a carrier. They have the Sickle Cell Trait.
- These individuals generally live a completely normal life without any symptoms, but they can pass the gene to their children.
Disease Transmission:
- If both parents are carriers (having SCT), there is a 25% probability in every pregnancy that the child will inherit the defective gene from both parents and be born with the active Sickle Cell Anaemia disease.
Prevalence in India
- Globally, SCA is most common among populations of African, Asian, and Mediterranean descent.
- In India, it represents a unique demographic challenge. According to a 2018 report by the Indian Council of Medical Research (ICMR), approximately 1.2% of the Indian population carries the Sickle Cell Trait.
- The disease is highly prevalent among certain tribal and non-tribal communities, primarily concentrated in states like Maharashtra, Madhya Pradesh, Chhattisgarh, Gujarat, Odisha, Jharkhand, and Bihar.
