Association between Plasmodium Falciparum Merozoite Surface Protein-1 (PFMSP-1) and severity of Falciparum malaria among Sudanese children

Background: Malaria is a global health  problem, with 241 million cases and 627,000 deaths in 2020 according to the WHO. In Sudan, The estimated malaria prevalence is 5.9% in which P. falciparum Incriminates 87.6% of cases and 12.4 %  with P. vivax. Clinical manifestation of reported malaria cases in Sudan varied widely from asymptomatic, mild uncomplicated to severe and fatal complications. Merozoite surface protein polymorphism (MSP) is an important parasite factor that has been correlated with the severity of falciparum malaria. Objectives: The present study aimed to investigate the allelic diversity of merozoite surface protein-1 gene (MSP-1) among the Plasmodium falciparum isolates in Sudanese childrenand to determine their potential correlation with the severity of falciparum malaria.  Materials and Methods: This study was conducted in Wad Medani Pediatric Teaching Hospital during September to December 2022. 89 children admitted with severe falciparum malaria were selected for this study. DNA was extracted from dry blood spots collected from them and polymerase chain reaction (PCR) amplified for the three MSP-1 allelic subfamilies. SPSS computer program (v 20.0) was used for data analysis. Results: The results found thatK1 allele was the common MSP-1 allele followed by RO33 and MAD20 with frequencies of 65 (73%), 55 (61.8%), and 17 (19.1%) respectively. There was strong association between RO33 allele and severity of infection with odd ratio (2.571) and P value (0.046). Also, in MAD20 allele there was high risk to develop severe malaria (Odd ratio = 1.2) but without significant association (P value = 0.70). Furthermore, K1 allele was less risky factor for severity of infection (P. value = 0.559, Odd ratio = 0.955). Regarding the common complications and their association with  MSP-1 alleles; the hypoglycemia had high risk with higher odd ratio 4.2 and 2.9  for K1 and MAD20 alleles respectively. Moreover, severe anemia was minor P. falciparum risk factor for all MSP-1 alleles (K1, MAD20 and RO33), other WHO criteria of sever malaria were less common. Conclusion: K1 allele was the most predominant circulating allelic family. There was strong association between RO33 and MAD20 alleles with the severity of infection. K1 allele was less risk factor for severity of infection. The hypoglycemia has high risk with K1 and MAD20 alleles.