학술논문
Molecular surveillance reveals the presence of pfhrp2 and pfhrp3 gene deletions in Plasmodium falciparum parasite populations in Uganda, 2017-2019
Plasmodium falciparum histidine rich protein 2 and 3
Plasmodium falciparum histidine rich protein 2 and 3
Document Type
Report
Author
Bosco, Agaba B.; Anderson, Karen; Gresty, Karryn; Prosser, Christiane; Smith, David; Nankabirwa, Joaniter I.; Nsobya, Sam; Yeka, Adoke; Opigo, Jimmy; Gonahasa, Samuel; Namubiru, Rhoda; Arinaitwe, Emmanuel; Mbaka, Paul; Kissa, John; Won, Sungho; Lee, Bora; Lim, Chae Seung; Karamagi, Charles; Cunningham, Jane; Nakayaga, Joan K.; Kamya, Moses R.; Cheng, Qin
Source
Malaria Journal. August 26, 2020, Vol. 19 Issue 1
Subject
Language
English
ISSN
1475-2875
Abstract
Author(s): Agaba B. Bosco[sup.1,2] , Karen Anderson[sup.3,4] , Karryn Gresty[sup.3,4] , Christiane Prosser[sup.4] , David Smith[sup.3,4] , Joaniter I. Nankabirwa[sup.1,5] , Sam Nsobya[sup.1,5] , Adoke Yeka[sup.1,5] , Jimmy Opigo[sup.2] , [...]
Background Histidine-rich protein-2 (HRP2)-based rapid diagnostic tests (RDTs) are the only RDTs recommended for malaria diagnosis in Uganda. However, the emergence of Plasmodium falciparum histidine rich protein 2 and 3 (pfhrp2 and pfhrp3) gene deletions threatens their usefulness as malaria diagnostic and surveillance tools. The pfhrp2 and pfhrp3 gene deletions surveillance was conducted in P. falciparum parasite populations in Uganda. Methods Three-hundred (n = 300) P. falciparum isolates collected from cross-sectional malaria surveys in symptomatic individuals in 48 districts of eastern and western Uganda were analysed for the presence of pfhrp2 and pfhrp3 genes. Presence of parasite DNA was confirmed by PCR amplification of the 18s rRNA gene, msp1 and msp2 single copy genes. Presence or absence of deletions was confirmed by amplification of exon1 and exon2 of pfhrp2 and pfhrp3 using gene specific PCR. Results Overall, pfhrp2 and pfhrp3 gene deletions were detected in 29/300 (9.7%, 95% CI 6.6-13.6%) parasite isolates. The pfhrp2 gene was deleted in 10/300 (3.3%, 95% CI 1.6-6.0%) isolates, pfhrp3 in 9/300 (3.0%, 95% CI 1.4-5.6%) while both pfhrp2 and pfhrp3 were deleted in 10/300 (3.3%, 95% CI 1.6-6.0%) parasite isolates. Proportion of pfhrp2/3 deletions was higher in the eastern 14.7% (95% CI 9.7-20.0%) compared to the western region 3.1% (95% CI 0.8-7.7%), p = 0.001. Geographical location was associated with gene deletions aOR 6.25 (2.02-23.55), p = 0.003. Conclusions This is the first large-scale survey reporting the presence of pfhrp2/3 gene deletions in P. falciparum isolates in Uganda. Roll out of RDTs for malaria diagnosis should take into consideration the existence of pfhrp2/3 gene deletions particularly in areas where they were detected. Periodic pfhrp2/3 surveys are recommended to inform future decisions for deployment of alternative RDTs. Keywords: Malaria rapid diagnostic tests, Plasmodium falciparum, Histidine rich protein 2, Histidine rich protein 3, Gene deletion, Deoxyribonucleic acid, Microscopy
Background Histidine-rich protein-2 (HRP2)-based rapid diagnostic tests (RDTs) are the only RDTs recommended for malaria diagnosis in Uganda. However, the emergence of Plasmodium falciparum histidine rich protein 2 and 3 (pfhrp2 and pfhrp3) gene deletions threatens their usefulness as malaria diagnostic and surveillance tools. The pfhrp2 and pfhrp3 gene deletions surveillance was conducted in P. falciparum parasite populations in Uganda. Methods Three-hundred (n = 300) P. falciparum isolates collected from cross-sectional malaria surveys in symptomatic individuals in 48 districts of eastern and western Uganda were analysed for the presence of pfhrp2 and pfhrp3 genes. Presence of parasite DNA was confirmed by PCR amplification of the 18s rRNA gene, msp1 and msp2 single copy genes. Presence or absence of deletions was confirmed by amplification of exon1 and exon2 of pfhrp2 and pfhrp3 using gene specific PCR. Results Overall, pfhrp2 and pfhrp3 gene deletions were detected in 29/300 (9.7%, 95% CI 6.6-13.6%) parasite isolates. The pfhrp2 gene was deleted in 10/300 (3.3%, 95% CI 1.6-6.0%) isolates, pfhrp3 in 9/300 (3.0%, 95% CI 1.4-5.6%) while both pfhrp2 and pfhrp3 were deleted in 10/300 (3.3%, 95% CI 1.6-6.0%) parasite isolates. Proportion of pfhrp2/3 deletions was higher in the eastern 14.7% (95% CI 9.7-20.0%) compared to the western region 3.1% (95% CI 0.8-7.7%), p = 0.001. Geographical location was associated with gene deletions aOR 6.25 (2.02-23.55), p = 0.003. Conclusions This is the first large-scale survey reporting the presence of pfhrp2/3 gene deletions in P. falciparum isolates in Uganda. Roll out of RDTs for malaria diagnosis should take into consideration the existence of pfhrp2/3 gene deletions particularly in areas where they were detected. Periodic pfhrp2/3 surveys are recommended to inform future decisions for deployment of alternative RDTs. Keywords: Malaria rapid diagnostic tests, Plasmodium falciparum, Histidine rich protein 2, Histidine rich protein 3, Gene deletion, Deoxyribonucleic acid, Microscopy