Sickle Cell Disease is the most significant genetic cause of childhood mortality worldwide. Of the 210,000 children born annually in Africa with the disease, only ten percent will survive childhood. This is even though simple interventions, such as neonatal screening and enrolment into comprehensive, effective care programmes, would prevent these deaths.
Tanzania is one of the member states of WHO where SCD is a public health problem, with the prevalence of carriers ranging between 15 – 20%, which is amongst the highest in Africa. The estimated birth incidence of children with homozygous SCD in Tanzania is between 6 to 7 per 1000 children, implying that within the next 5 years there will be over 60,000 children born with SCD. The majority of these children will not know that they have SCD and although there is a wide variation in the severity of disease in affected children, these children have a high chance of early death and for those who survive, they will require life-long hospital care for acute and chronic complications, with the average cost for managing one patient ranging between 4,425 to 7,000$ per year.
Major benefits in the health and survival of children with SCD outside of Africa have been attained through the implementation of a few, simple evidence-based interventions. The most striking achievements have been as a result of early diagnosis of SCD by neonatal screening and the subsequent enrolment of these patients into comprehensive, effective care programmes. These interventions have not yet been introduced in Tanzania, despite the fact that they have been shown to be highly effective in developed countries. This is partly owing to the limited awareness within Tanzania about the burden and complications of SCD and the options for detection, treatment and prevention of SCD.
The Wellcome Trust (WT) has funded research at MNH and MUHAS in Dar es Salaam, Tanzania since 2004, establishing a cohort of over 2000 patents with SCD. The research focused on three potential areas of severe morbidity and mortality in SCD: malaria, bacterial infections and severe neurological outcomes (stroke). In the current phase, the WT has funded the cohort (2011-2015) through a strategic award (C Newton). Dr Makani has been awarded a WT intermediate fellowship (2011/2016) to research aetiology and management of anaemia in SCD in the African setting, including a clinical trial of hydroxyurea therapy. Her colleague, Dr Sharon Cox has also been awarded a WT grant to conduct a clinical trial of a nutraceutical intervention to improve growth and vascular function in SCD (2011-2013).
Dr Makani collaborates with Dr Inês Barroso, head of the Metabolic Disease Group at the Wellcome Trust Sanger Institute (WTSI) and Dr Jeff Barrett from (WTSI) Human Genetics to employ a Genome Wide Association Study (GWAS) design to study SCD. This is a multidisciplinary team that combines large-scale genetic and genomic approaches, and studies in model organisms, to understand the aetiology of various metabolic diseases. It is actively engaged in developing partnerships with collaborators in Africa.