Regional
The impact of malaria vaccine in global blood supply in malaria-endemic regions
Beukou Fonkou Steve
MD, Tranfusion Medicine Specialist at Cameroon Baptist Convention Health Services (CBCHS), Cameroon
Blood transfusion is lifesaving treatment modality in severe anemia. In malaria endemic zones such as sub-Saharan Africa (SSA), severe anemia are not uncommon. The mean severe anemia from malaria in SSA is 3.7% in children under the age of 51. Moreover, the recent WHO African region status report on blood availability, safety and quality of 2022, revealed the pediatrics services had the highest proportions of blood units issued in the Central and West Africa region (30 and 24.5% respectively)2.
Isidoros et al, evaluated the potential of malaria-anemia comorbidity prevalence to quantify under five malaria-related deaths in SSA. 9 out of the 16 countries in the study had a statistically important association; Benin, Burkina Faso, Burundi, Cote d’Ivoire, Democratic Republic of Congo (DRC), Guinea, Senegal, Togo1. With the challenges to bridge the demand and supply of blood units in these regions, the availability of the blood components plays a crucial role in strengthening the health system in this regards.
On July 5th 2023, the WHO announced the rolling out of 18 million doses of the first-ever malaria vaccine (RTS,S/AS01) to 12 African countries (Benin, Burkina Faso, Burundi, Cameroon, Democratic republic of Congo, Ghana, Kenya, Liberia, Niger, Sierra Leone and Uganda)3. This should be a game changer when looking keenly at the results of the pilot phase. It is reported that, in combination with the season malaria chemoprevention, severe malaria anemia was reduced by 68%4. Thus, we could have a significant reduction in blood units issued for these. This has the potential to re-distribute the scarce blood towards other units especially in the obstetrics services where maternal mortality is an issue.
Figure 1: Bar chart showing transfusions in the pediatrics ward of Baptist Hospital Mutengene, Cameroon in 2022
Modelling these findings in one of our institution, that is, Baptist Hospital Mutengene (BHM), Cameroon, could give us a vivid appraisal of the impact of this vaccine. In 2022, from January to November we registered a total of 298 blood transfusions in the pediatric services. 45% of these was indicated for patients with severe malaria with 71% being under the age of 5 years (Figure 1). Assuming these patients had received the vaccine, 92 blood units would have been available for other uses. Extrapolating this to the central and West African region.
Therefore, it would be important for the clinical transfusion and global blood safety working parties of the ISBT in collaboration with the WHO, to set-up a monitoring and evaluation strategy for these 12 pioneer countries and have evidence-based implications of deploying the malaria vaccine in all malaria endemic areas in relation to attending global blood safety.
References
1. Isidoros P, Jurg U, Penelope V. Malaria-anemia comorbidity prevalence as a measure of malaria-related deaths in sub-Saharan Africa
2. WHO African Region status report on blood availability, safety and quality. Brazzaville: WHO Regional Office for Africa; 2022. Licence: CC BY-NC-SA 3.0 IGO
3. World Health Organization. 18 million doses of first-ever malaria vaccine allocated to 12 African countries for 2023-2025: Gavi, WHO and UNICEF. https://www.who.int/news/item (accessed August 28th 2023)
4. Malaria Vaccine Implementation Programme Advisory Group. Full Evidence Report on the RTS,S/AS01 malaria vaccine. World Health Organization-SAGE meeting. October 2021
