By Joke Kujenya
ON HOSPITAL wards in Ogbomoso, Osun State, Nigeria—where the realities of HIV and malaria overlap daily—scientists have uncovered new insights into how Plasmodium falciparum behaves in immunocompromised individuals.
New research has revealed that malaria parasites found in people living with HIV (PLWH) show unexpectedly low genetic diversity, raising questions about shifting transmission patterns and the long-term impact of malaria control efforts.
The study, conducted by a team of Nigerian medical scientists—including Odesola Damilola E., Mbabie Ure C., Makinde Oreoluwa H., Olaosebikan Iyanuoluwa O., James Ogunniran A., Ayoola Adeola O., Opaleye Oluyinka O., and Ojurongbe Olusola—analysed blood samples from 254 HIV-positive patients receiving care at Ladoke Akintola University of Technology (LAUTECH) and BOWEN Teaching Hospitals.
Participants were mostly women, averaging 40.7 years of age.
Each sample underwent three layers of testing: rapid diagnostic tests (RDT), microscopy, and nested polymerase chain reaction (nPCR). Detection rates varied: 5.9% via RDT, 55.1% by microscopy, and 40.6% through nPCR—highlighting the difficulty of accurately diagnosing malaria in HIV-affected populations.
Beyond detection, the research spotlighted parasite genetics. Scientists genotyped three polymorphic genes—msp-1, msp-2, and glurp—to assess diversity.
The msp-1 gene revealed 170 unique variants a cross three primary families: K1 (34.7%), MAD20 (30.0%), and RO33 (35.3%).
The msp-2 gene displayed 56 alleles, with the FC27 family dominating at 73.2%.
Multiplicity of infection (MOI)—a measure of co-infecting strains—was highest for msp-1 (2.02), but significantly lower for msp-2 (1.13) and glurp (1.00).
Expected heterozygosity (HE), reflecting genetic variability, followed a similar trend: 0.86 for msp-1, 0.52 for msp-2, and just 0.10 for glurp.
Polyclonal infections were common in msp-1 (68.5%) and glurp (31.1%), suggesting ongoing exposure to diverse parasite strains.
However, a predominance of monoclonal msp-2 infections (22.1%) hinted at a narrowing genetic pool.
These findings suggest that even in high-transmission regions like Ogbomoso, the genetic landscape of P. falciparum in PLWH may be contracting—possibly due to control interventions or evolving epidemiological factors.
While the clinical implications are still being studied, reduced parasite diversity could impact transmission dynamics and treatment strategies, particularly in immunocompromised groups.
The researchers also call for further investigation to determine the drivers behind this shift and how it might inform future malaria and HIV co-management approaches.
They warned that in regions where dual epidemics converge, even subtle pathogen changes carry profound public health significance.
