“Sickle cell is a true public health problem with medical, human and social dimensions,” Oumar Ibrahima Touré, Mali’s health minister until earlier this month, told IRIN.
Despite advances in treatment and research over the past century, SCD is still largely undiagnosed in the world's most affected areas where the problem is too complex for any quick-fix solutions, researchers say.
And without treatment there is a 50 percent chance a sickle cell patient will die before the age of five, most commonly of a blood infection.
For its impact on lives and livelihoods, SCD has been deemed a “threat to the economic and social development of Africa” by the West Africa-based Federation of Associations Combating Sickle Cell Disorder in Africa (FALDA).
“People still don’t know about this sickness and there’s a lot of judgment, forcing sick people to hide,” said Dramane Banao, president of a national initiative to fight SCD and mother of a 19-year-old woman with SCD in the West African country of Burkina Faso.
Sickle cell disease is inherited and present at birth, but can show no symptoms for the first four months of life.
Characterized by irregular haemoglobin (iron-rich, oxygen-transporting protein in red blood cells), the disease causes red blood cells to morph into a sickle-shape (crescent) instead of a disc, which leads to clumping and blocked blood vessels.
This clumping can cause pain, infection and, in some cases, organ damage.
When sickle-shaped cells die, sickle cell anaemia, the most common form of SCD, takes hold.
Anti-cancer drugs and bone marrow transplants have extended the life expectancy of sickle cell patients into their 50s.
“Life expectancy has increased, which is a huge accomplishment in the fight against the disease,” Dapa Diallo, director-general of the Centre for Sickle Cell Disease in Mali, said. “Sickle cell cannot be cured, but with proper care [the health of a patient] can be improved.”
But life expectancy for a person with SCD in Africa, where a proper diagnosis is scarce, is still less than 20 years on average.
“They didn’t know at all what the sickness was and treated me for malaria,” Abdoul Karim Ouedraogo, a 42-year-old sickle cell patient, said. At first, he was thought to be cursed, and now walks with crutches when SCD, prior to his diagnosis, damaged his hip.
Condition in which the blood has a lower than normal count of red blood cells.
An iron-rich protein in red blood cells that carries oxygen from the lungs to the entire body. Sickle cell disease is characterized by irregular haemoglobin.
|Sickle cell anaemia
Healthy red blood cells live about 120 days in the bloodstream, but sickle-shaped ones die within 20 days, which creates a shortage of red blood cells and less oxygen movement. This is the most common form of sickle cell disease.
When an offspring is born to two parents who carry the sickle cell trait.
|Sickle cell crisis
Sudden pain throughout the body when blood clumps and oxygen is not delivered. A crisis can last from hours to weeks.
|Sickle cell trait
Carrying one copy of the sickle cell gene does not translate into experiencing symptoms of the disorder; rather, the trait is passed to offspring, which have a 50 percent chance of carrying the disease and a 25 percent chance of having two copies of the trait, and thus having the disease.
|Source: US National Institutes of Health|
Up to one in four adults in sub-Saharan African countries like Nigeria carry the sickle cell trait, according to the World Health Organization (WHO).
Though carriers do not necessarily experience symptoms, testing is recommended for genetic counselling. A man and woman, if both are carriers, have a 25 percent chance of having a child with SCD.
But the development of genetic testing, which has resulted in improved prenatal diagnosis in some parts of the world, is underutilized in the most heavily affected parts of West Africa, and has even led to discrimination and fear.
Finding a marriage partner can prove difficult for carriers of the trait: Carriers can be perceived as being sentenced to having a very sick child.
“We see ourselves as burdens on our families,” Moussa Soulale, diagnosed at 13 and now 25, said from Mali where she is a teacher who has learned to live with her illness.
Screening, education, prenatal diagnosis and treatment have proven effective in fighting the disease among smaller populations, such as in the eastern Mediterranean country of Cyprus.
But affected countries in Africa - where some populations have up to a 45 percent carrier rate, according to WHO - pose other challenges.
“The level of care and quality of management of the crisis are not well studied in Africa,” said Brahima Soumaoro, a Mali-based medical researcher.
There is an urgent need to put in place training for health workers “based on standards of proven efficacy,” he said, in the hope of containing SCD as it has been contained in the USA and Europe.
1910: James Herrick, a doctor in Chicago in the USA notices “peculiar elongated and sickle shaped” blood cells in Walter Clement Noel, a dental student from Grenada suffering from anaemia. Sickle cell disease, though known for years in Africa, was then formally reported in the US medical journal, Archives of Internal Medicine.
1917: The genetic basis for sickle cell is first suggested by Victor Emmel, an American anatomist, in the US medical journal, Archives of Internal Medicine.
1922: Three more cases are reported in the USA and the disease is formally named.
1923: Doctors at the Maryland-based Johns Hopkins University conclude sickle cell disease is an “autosomal recessive characteristic” - two copies of the gene must be present for it to be expressed.
1927: It is discovered that “sickling” happens because of a lack of oxygen.
1940: The connection is made between abnormal haemoglobin and the tendency of red blood cells to sickle.
1949: It is determined that carrying the sickle cell trait can be symptomless.
1954: Anthony Allison hypothesizes that the sickle cell trait offered protection against malaria. As more research was done, it is discovered that those with the sickle cell trait, not the disease, are protected against malaria. But those with sickle cell disease either die from the blood disorder or die after coming into contact with malaria because of a weakened immune system. Subsequent research has called into question the sickle cell trait’s ability to protect against malaria.
1970s: Forced testing for black people proliferates when sickle cell screening programmes began in the USA.
1979: Calculations suggest the sickle cell gene developed 70,000-150,000 years ago.
1994: It is recognized that all of the areas where sickle cell disease originated have been, or are now, endemic locations of malarial infestation.
1995: Hydroxyurea, an anti-cancer drug, is found to be an effective therapy in reducing complications from SCD.
1996: Bone marrow transplants are now used to treat sickle cell disease in children.
1996: The Federation of Associations Combating Sickle Cell Disorder in Africa (FALDA) is formed.
2000: The introduction of pneumococcal vaccine greatly reduces child mortality in the USA as those with SCD were at high risk of developing pneumococcal meningitis.
2003: Hydroxyurea increases life expectancy for sickle cell patients.
2010: Mali President Amadou Toumani Touré opens a research centre to promote SCD research, training and genetic counselling for medical follow-up, with the ambition of creating globally influential advancements. Touré calls the centre part of the fight against poverty.