Why in news:
Prime Minister launches National Sickle Cell Anaemia Elimination Mission from Shahdol, Madhya Pradesh.
Sickle cell anaemia (SCA), a genetic blood disorder, found mention in the Budget this year. Finance Minister Nirmala Sitharaman said that the government will work in “mission mode” to eliminate the condition by 2047. India is the second-worst affected country in terms of predicted births with SCA — i.e. chances of being born with the condition.
 
What is sickle cell anaemia? 
In 1910, a physician named James Herrick wrote of discovering unusual red blood cells in an anaemic student from Granada, Spain. Unusual, because unlike their usual globular structure with an indented center – like a doughnut with a hole – these blood cells were shaped like a sickle, similar to the letter C. This was the first description of sickle cell anaemia in western medical literature.
Haemoglobin which is tasked with carrying oxygen to all parts of the body has four protein subunits — two alpha and two beta. In some people, mutations in the gene that creates the beta subunits impact the shape of the blood cell and distort it to look like a sickle. 
A round red blood cell can move easily through blood vessels because of its shape but sickle red blood cells end up slowing and even blocking, the blood flow. Moreover, sickle cells die early, resulting in a shortage of red blood cells that deprive the body of oxygen. 
These obstructions and shortages may cause chronic anaemia, pain, fatigue, acute chest syndrome, stroke, and a host of other serious health complications. Without treatment, quality of life is compromised and severe cases can become fatal in the initial years of life.

Does SCA only affect some?  
In India, first descriptions of SCD came around 1952, when researchers H. Lehmann and Marie Cutbush were studying tribal populations in the Nilgiri hills. The presence of the sickle haemoglobin was also reported around this time in tea garden workers of Upper Assam – labourers who had migrated from tribal groups in Bihar and Odisha. Research and screening programmes have found that the prevalence of haemoglobinopathies — disorders of the blood — is more common among tribal populations than non-tribal communities in India.
Research has shown that SCA is prevalent in communities residing in areas where malaria is endemic. Around the middle 1940s, doctors found that those with sickle red blood cells were more likely to survive malaria. Those with the trait in some African countries were found to be potentially resistant to lethal forms of malaria and had a survival advantage. The sickle cell trait thus gave an evolutionary advantage, offering immunity to some people during malaria epidemics. 
In India, States and UTs with tribal populations contribute a significant malaria caseload. Additionally, the documented prevalence of SCA is higher in communities that practice endogamy, as the chances of having two parents with sickle cell trait is higher.

Can it be treated?  
Sickle cell anaemia is a genetic disorder, making complete “elimination” a challenge that requires a major scientific breakthrough. The only cure comes in the form of gene therapy and stem cell transplants — both costly and still in developmental stages. In gene therapy, the DNA inside the haemoglobin gene is edited to stop the disease while in stem cell transplants, the bone marrow affected by sickle cell anaemia is replaced with healthy bone marrow from a donor. Both interventions are currently being tested in clinical trials globally. Blood transfusion, wherein red blood cells are removed from donated blood and given to a patient, is also a trusted treatment in the absence of permanent cures. But challenges include a scarcity of donors, fears around safe supply of blood, risk of infection etc.
 
What has India done so far? 
The Indian Council of Medical Research and the National Rural Health Mission in different States are undertaking outreach programmes for better management and control of the disease. The Ministry of Tribal Affairs launched a portal wherein people can register themselves if they have the disease or the trait, in order to collate all information related to SCA among tribal groups.
The National Health Mission guideline on Hemoglobinopathies also identifies “establishing services at the community level for pre-marital and pre-conception screening backed by genetic counselling services” as a strategy for addressing SCA. Genetic counselling involves creating awareness and advising two carriers about the risks of having biological children. In pre-marital counselling, partners are provided with the knowledge of how their sickle genes could affect the newborn baby. They are “free to choose the path which is most comfortable to them... the genetic counsellor will not tell the patient what to do”, the Chhattisgarh government’s manual on SCA states.
In the Budget, the Union Health Minister said the government plans to distribute “special cards” across tribal areas to people below the age of 40. “The cards will be divided into different categories based on the screening results.” The mission will receive funding under the National Health Mission.

About National Sickle Cell Anaemia Elimination Mission:  
The National Sickle Cell Anaemia Elimination Program, introduced in the Union Budget 2023, focuses on addressing the significant health challenges posed by sickle cell disease, particularly among tribal populations of the country. Sickle cell disease (SCD) is a chronic single gene disorder causing a debilitating systemic syndrome characterized by chronic anemia, acute painful episodes, organ infarction and chronic organ damage and by a significant reduction in life expectancy. Implemented in 17 high-focus states across the country, this program aims to improve the care and prospects of all sickle cell disease patients while reducing the prevalence of the disease. The 17 states are- Gujarat, Maharashtra, Rajasthan, Madhya Pradesh, Jharkhand, Chhattisgarh, West Bengal, Odisha, Tamil Nadu, Telangana, Andhra Pradesh, Karnataka, Assam, Uttar Pradesh, Kerala, Bihar, and Uttarakhand.
The program is executed in a mission mode as part of the National Health Mission (NHM), aims to eliminate sickle cell genetic transmission by the year 2047, showing a long-term commitment to eradicating the disease.
Over a period of three years, spanning from the fiscal year 2023-24 to 2025-26, the program targets screening approximately 7.0 crore people. This ambitious goal highlights the program's dedication to reaching a large portion of the population, promoting early diagnosis and intervention.

Mains Practice question:
Q. In the context of National Sickle Cell Anaemia Elimination Mission, discuss various health issues of tribals in India.