Sickle cell disease prevention and control

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Sickle Cell Disease (SCD) is a major genetic disease in most countries in Sub-Saharan Africa. In recognition of this, the WHO under the DNC Department, supervise and coordinate interventions relating to the prevention and management of SCD. WHO intends to support Primary prevention (genetic counselling, general public knowledge); Early detection - screening; reduce morbidity ; chemoprophylaxis, vaccines, clinical care of special groups (children, pregnant women); capacity building Human resource; improve quality of life of patients and build partnerships.

Sickle-cell disease (SCD) is a genetic blood disorder that affects the haemoglobin within the red blood cells. The recurrent pain and complications caused by the disease can interfere with many aspects of the patient’s life, including education, employment and psychosocial development.

The sickle-cell trait is now known to be widespread, reaching its highest prevalence in parts of Africa as well as among people with origins in equatorial Africa, the Mediterranean basin and Saudi Arabia. In Africa, the highest prevalence of sickle-cell trait occurs between latitudes 15° North and 20° South, ranging between 10% and 40% of the population in some areas.

Prevalence levels decrease to between 1% and 2% in north Africa and to less than 1% in southern Africa. In countries such as Cameroon, Republic of Congo, Gabon, Ghana and Nigeria, the prevalence is between 20% and 30% while in some parts of Uganda it is as high as 45%. In countries where the trait prevalence is above 20% the disease affects about 2% of the population. The geographic distribution of the sickle-cell trait is very similar to that of malaria. The sickle cell trait has a partial protective effect against malaria, and this may explain why it has been maintained at such high prevalence levels in tropical Africa. Those who inherit the gene from both parents do not have this protection. In addition, they suffer from severe effects of SCD and many die before they reach reproductive age.

In some countries where SCD is a major public health concern, control programmes do exist; however, these have neither the national coverage nor basic facilities to manage patients. Systematic screening for SCD using a simple blood test is not a common practice, and diagnosis is usually made when a severe complication occurs.

Counselling and prevention of causes and infections are simple measures not readily accessible to most patients. As a result, the majority of children with the most severe form of the disease die before the age of five, usually from an infection or severe anaemia. The survivors remain vulnerable to exacerbations of the disease and the complications mentioned above.

SCD has major social and economic implications for the affected child as well as the family. Recurrent sickle-cell crises interfere with the patient’s life, especially with regard to education, work and psychosocial development.

Presently, there is no cure for SCD. However, cost-effective treatment exists for the pain and other aspects of the disease. The most important components of this treatment are early intervention with analgesics, antibiotics, rest, good nutrition, folic acid supplementation and high fluid intake. At times, invasive procedures such as blood transfusions and surgery may be needed.

Research in some countries in the Region (Benin, Burkina Faso, Nigeria, Togo) has yielded therapeutic agents effective in preventing or reducing the frequency and severity of crises.

There is sufficient evidence that neonatal screening for sickle-cell disease, when linked to timely diagnostic testing, parental education and comprehensive care, markedly reduces morbidity and mortality in infancy and early childhood. Nevertheless, simple, inexpensive and cost-effective procedures such as the use of penicillin to prevent infections are not available to most patients.

The way forward

Creation or strengthening of national sickle-cell disease control programmes within the framework of national programmes for prevention and control of noncommunicable diseases is necessary in affected countries. Essential areas of work should cover advocacy; prevention and counseling; early detection and treatment; data collection, surveillance and research; and community education and partnerships. A multidisciplinary team involving health and social workers, teachers, parents and concerned nongovernmental organizations could be established to work on the practical aspects of implementation and monitoring of the programme.

Prevention entails setting up sickle-cell screening and genetic counseling programmes in high prevalence countries. Ideally, the disease should be identified during the prenatal period or at birth as part of a routine screening programme. Such services should be available alongside counseling and health education services since diagnosis raises serious ethical and cultural issues which differ from one country to another. Genetic counseling and screening can lead to substantial reduction in the number of children born with the trait.

Management of sickle-cell disease at different levels of the health-care system should emphasize programmes that use simple, affordable technology and are accessible to a large proportion of the community; such programmes are preferred instead of a parallel system which may be too expensive and unsustainable. The programme should be developed at the primary care level with appropriate technical and patient referral support from higher levels of care. Training of health personnel in prevention, diagnosis and case management should ensure that the health-care system is able to provide the basic requirements of these services. Family and community-based care should be an integral part of the national programme.

Surveillance and research are important components of the programme. The information generated should be disseminated and used as evidence in policy-making as well as in day-to-day decision-making in the management of the programme. It is also necessary to study the natural history of the disease and its effects on clinical manifestations and transmission of malaria.

Partnerships should be fostered between health professionals, parents, patients, relevant community interest groups and the media, where appropriate. Partnerships will facilitate public education, identification of genetic risks in the community by recording family disease histories, genetic counseling, awareness and active participation in prevention and care programmes.

Focal person for Sickle Cell Disease:
Dr. Boureima H. Sambo
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