Determining the Association Between MSP1/2 Variant and Multiplicity of Infection on Incidence of Severe Malaria in Sudanese Children in Gezira State, Sudan

The Almanagil province located in Gezira scheme, Gezira state, Sudan, represents a suitable environment
for the breeding of malaria-carrying mosquitoes. An estimated 5.9% of Sudanese people suffer from
malaria, with 87.6% of cases caused by Plasmodium falciparum and 12.4% by Plasmodium vivax. Clinical
manifestation of malaria cases range from mild uncomplicated to severe and fatal complications and
the genetic variants and multiplicity of falciparum infection can worsen the manifestations of malaria.
The objective of this work is to determine the degree of genetic variation in P. falciparum infection
in a high-transmission region of central Sudan by analyzing merozoite surface protein-1 (msp1) and
merozoite surface protein-2 (msp2) variations. During the rainy season of 2022, Eighty-nine children
with confirmed severe falciparum malaria whom admitted to Almanagil Pediatric Hospital were
included in this study. Dry blood spots were used to extract the DNA and amplification of three msp1
and two of msp2 allelic subfamilies, namely K1, RO33 and MAD20 and FC27 and IC/3D7 respectively.
The data was analyzed by using SPSS computer program (v 23.0). The three genetic subfamilies of
msp1 (K1, RO33 and MAD20) and the two alleles of msp2 (FC27 and IC/3D7) were identified. Msp1
variants represent K1 (64/89, 71.9%), RO33 (56/89, 62.9%) and MAD20 (72/89, 80.9%), while msp2
diversity represents ICI/3D7 (52/89, 58.4%), FC27 (62/89, 69.6%) and ICI/3D7/FC27(33/89, 37.1%). The
MAD20 and FC27 showed high genetic diversity among both genes, respectively. RO33 allele shows
a strong association with severity of falciparum malaria (OR 2.572, P 0.045 ), while the K1 was the
lowest risk factor for malaria severity. The allele subfamily K1 and MAD20 of msp1 were associated
with hypoglycemia (OR 4.21 and 2.91), respectively. Our study revealed high genetic polymorphisms
of msp1 and msp2. Among Central Sudanese children with high MOI of P. falciparum isolates, there
was a significant frequency of msp1, a strong association between the K1 allele and hypoglycemia,
and a substantial association between the RO33 and MAD20 alleles with the severity of the infection.
These findings could help develop malaria control strategies.