World Malaria Day 2024
The University of Port Harcourt joined family, friends and well-wishers of Prof Sylvanus JS Cookey to celebrate his 90th birthday. Professor Cookey who was the 2nd Vice-Chancellor of the University, also endowed a chair in malaria studies as his contribution to the roll back malaria effort to eliminate malaria and reduce the burden of the disease in Nigeria.
In his welcome remarks at the event, the Sylvanus JS Cookey Professor of Malaria Studies and the Deputy Vice-Chancellor Research and Development, Prof I M Siminialayi had said that “For several years now, the World Health Organization has prioritized the prevention of malaria, with the goal of reducing the huge death toll to 40,000 people from 580,000, most of them Nigerians and Africans, attributed to malaria yearly. Efforts aimed at highlighting prevention have steadily reduced the death toll, especially using insecticides, mosquito nets and now vaccines.
The Legacy Lectures we hold here, are in the spirit of World Malaria Day, to help educate the university and host communities on the latest developments in the prevention of malaria. We are lucky that our benefactor was born on April 9, a few weeks before April 25, when the World celebrates Malaria Day.
To deliver the 2024 Legacy Lecture on the 8th of April, as part of the week-long activities the organisers had invited Prof Ousmane Koita. Prof Koita is a highly respected Malian Professor of Cell and Molecular Biology, and the Director of the Laboratory of Applied Molecular Biology at the University of Science, Techniques and Technology of Bamako (USTTB). He has been a full professor of Molecular Biology at USTTB since its inception and an Associate Professor at the Department of Tropical Medicine, Tulane University, New Orleans, USA. He is Director of Laboratoire Mixte International DYN-PATHOS, and in addition serves as Principal Investigator of the President’s Malaria Initiative (PMI)/USAID Malaria Therapeutic Efficacy Study.
The lecture which was titled “Prospects of Eliminating Malaria from Sub-Saharan Africa” highlighted the genetic recombination and gene deletion in the malaria parasite and discussed the challenges of malaria elimination.
Prof Koita’s laboratory had done malaria parasite genotyping in children 4-18 years old. They discovered that most patients had the Papua New Guinea strain (MAD 20), the Ghanaian strain (RO33) or a hybrid strain (MAD20/RO33). Their study of malaria transmission in relation to habitat and season, revealed the disappearance of some genes during the malaria off-season. This had implications for malaria diagnosis and prevention with vaccines. For instance, 26 of 480 smear-positive false-negative RDT results using an HRP2-based RDT. PCR amplification for the histidine-rich repeat region of hrp2 was negative in half (10/22) of the false negatives, consistent with spontaneous deletion of hrp2 or its central region.
Previous studies had indicated that the multiplicity (complexity of) infection (MOI) is lower in specimens with true-positive RDTs: false negative gave 1.00 ± 0.00 (n=12) while true positives gave 2.42 ± 0.84 (n=19).
Prof Koita explained that three or more factors may explain or contribute to seasonal variation in the frequency of false-negative RDTs:
- Spontaneous HRP2 deletions
- Lower MOIs during the dry season which potentially also increase false-negative RDT results and
- Less frequent acquisition of new infections because of less intense transmission during the dry season.
The implication of these results for malaria control given as follows:
- Regardless of the mechanism(s) involved, false-negative RDTs pose a challenge for malaria control.
- Improved malaria control paradoxically decreases the sensitivity of RDT because it reduces both parasite densities and multiplicity of infection.
- As a result of 2 above, sensitivity of the RDT may progressively worsen as malaria control improves.
- The issue of false-negative RDTs is a priority for country-specific malaria control programs in endemic areas as well as international groups (PMI, WHO).
He surmised the findings of the study by saying that the recombinant parasite is produced during the meiotic reduction division in the mosquito. The size polymorphisms observed in these sequences are consistent with crossover events at 9 bp intervals based on repeating TCA trinucleotides in Block 2. Approximately 2.5% of P. falciparum circulating in Mali lack the hrp2 gene.
The RTS,S/ASO1 Vaccine trialled in some countries in Africa has only a modest efficacy of 30%. Taking into account the gene polymorphism of candidate vaccines and the high plasticity of the parasite genome, the selection of resistant strains of TRS,S resulting from massive immunization schemes is a real possibility. Despite its limited efficacy, the TRS,S vaccine raised significant ethical concerns, particularly regarding the fact that it was trialled in children.
In 2022 more than 233 million Africans contracted malaria, leading to 580,000 deaths according to the WHO. Nigeria leads the continent with the most malaria-related deaths in the world, contributing 31.1% of all deaths due to malaria. Faced with this burden, Prof Koita says “we must urgently prioritize the elimination of malaria and address the challenges before us so that Nigeria and other sub-Saharan African countries can be free of this disease.”
He called for increased collaboration between the Nigerian government and other regional governments, and for governments to demonstrate a strong political commitment to end malaria. Additionally, he says governments must allocate increased funds to the fight against malaria recognising that this is not a European or American problem, but an African problem that requires African solution.
As if in response to the call by the respected Cell and Molecular Biologist, the Rivers State Malaria Elimination program as part of its World Malaria Activities on Monday April 29, invested the Deputy Governor of the State Her Excellency, Prof. (Mrs) Ngozi Nma Ordu DSSRS as an End Malaria Champion.
The Deputy Governor, described by the Deputy Vice Chancellor, Research and Development Prof. Siminialayi, who read her citation at the event, as an accomplished microbiologist, an administrator of the highest calibre, a virtuous woman, a woman of substance and a truly deserving champion for the end malaria effort, is a former Permanent Secretary of the Ministry of Health and a former Commissioner for Education in the State.
She brings to the role a massive amount of experience on the workings of government and a network of women organisations and other resources. It is hoped that her efforts leading the End Malaria Council in the State which is about to be inaugurated will bring about desired results.
