Sickle cell disease is most common globally in sub-Saharan Africa. Up to 45% of sub-Saharan Africans are carriers of the disorder. Sickle cell disease appears to have evolved as an adaptation against malaria, which is why it would be so prevalent in these African countries. For example, Zambia is one of the 20 countries in the world with the highest malaria incidence and mortality. About 2% of the world’s sickle cell disease cases occur in Zambia, and about 5% of cases in eastern and southern Africa occur in the country.

Alarmingly, after significant progress in controlling the disease in the 2010s, sickle cell in Zambia started to escalate in 2020. In fact, during the first half of 2020, sickle cell cases, test positivity and mortality increased from 30% to 50% between 2018 and 2019. That is why as of 2021, the Zambian Ministry of Health recognizes sickle cell disease as a public health crisis. Specifically, 20% to 25% of the Zambian population is a carrier and 1% to 2% of children born in Zambia have the disease. That is why early screening programs are so important in fighting sickle cell disease in Zambia.

Sickle Cell Disease

Sickle cell disease is actually a group of conditions that cause misshapen red blood cells called “sickle cells.” Most red blood cells look like discs, but sickle cell patients have red blood cells that look like sickles or crescents. Sickle cells tend to stick together and obstruct the movement of blood, which makes sickle cell patients more vulnerable to infection. Also, sickle cells are more easily breakable than non-diseased red blood cells. This can lead to patients not having enough blood cells, a condition known as anemia.

Patients with sickle cell disease experience pain when the blood cells clog blood vessels. This pain may last a short time or for hours. Also, their anemia makes them often feel tired. Although it is not clearcut what triggers a sickle cell crisis, being overly cold or overly stressed seems to provoke incidents. Finally, other illnesses and dehydration trigger sickle cell crises.

Treatment for Sickle Cell Disease

Luckily, there are drugs that treat sickle cell disease. To prevent pulmonary infections, to which sickle cell disease patients are more prone, health professionals commonly prescribe penicillin. They also suggest that all sickle cell patients stay fully vaccinated. To prevent anemia, patients take folic acid to help the body manufacture new red blood cells. Additionally, medical professionals frequently prescribe the medication hydroxyurea to decrease the stickiness of red cells and adverse effects of the disease. If an infection or anemia still occurs, patients may need hospitalization. There, they receive more intensive medicine, including blood transfusions. Bone marrow transplants can cure sickle cell disease by replacing the diseased blood with healthy blood from a donor. However, not everyone is a candidate for a bone marrow transplant, and the procedure has a lot of risks.

Newborn diagnosis, careful monitoring and access to care results in survival to adulthood in 96% of cases of sickle cell disease. That is why all 50 states and the District of Columbia in the United States mandate sickle cell screening. European countries also have robust screening programs. However, in Africa, where newborn screening is sparse, up to 80% of children born with the disease die before they turn 5 years old. Zambia is working assiduously to improve its sickle cell screening and launched its newborn screening program in April 2021.

Zambia Launches Screening Program

Zambia’s Sickle Cell Disease (SCD) Newborn Screening (NBS) program focuses on early therapeutic intervention and builds on the country’s framework for early vaccination and HIV screening. The program hopes to annually screen 10,000 newborns and develop an electronic database of patient demographics, medical history and laboratory records. Initially, the program will screen at three sites in northwest Zambia.  The screening program involves taking a blood test sample from infants at different hospitals and sending the sample to its Tropical Diseases Research Center.

Additionally, through the Consortium of Newborn Screening in Africa (CONSA), scientists can use newborn screening data on the disease in the future so they can map out the disease in Zambia and across Africa to inform treatment and prevention. Dr. Jonas Kamina Chanda, the Zambian minister of health, claims that the new screening “marks an important milestone in the health sector, as well as those living or caring for someone with sickle cell disease.” Hopefully, Zambia will serve as a model for other African countries that do not currently screen to offer such a critical service to their citizens as well.

– Mikaela Marinis
Photo: Pixnio