Assessment of subpatent Plasmodium infection in northwestern Ethiopia.
Adolescent
Adult
Child
Child, Preschool
Cross-Sectional Studies
Disease Eradication
/ methods
Dried Blood Spot Testing
Ethiopia
/ epidemiology
Female
Humans
Malaria, Falciparum
/ diagnosis
Malaria, Vivax
/ diagnosis
Male
Middle Aged
Plasmodium falciparum
Plasmodium vivax
Prevalence
Seroepidemiologic Studies
Young Adult
Asymptomatic infections
Ethiopia
Malaria
Sub microscopic infections
Subpatent infections
Journal
Malaria journal
ISSN: 1475-2875
Titre abrégé: Malar J
Pays: England
ID NLM: 101139802
Informations de publication
Date de publication:
04 Mar 2020
04 Mar 2020
Historique:
received:
20
11
2019
accepted:
22
02
2020
entrez:
6
3
2020
pubmed:
7
3
2020
medline:
21
10
2020
Statut:
epublish
Résumé
Ethiopia has set a goal for malaria elimination by 2030. Low parasite density infections may go undetected by conventional diagnostic methods (microscopy and rapid diagnostic tests) and their contribution to malaria transmission varies by transmission settings. This study quantified the burden of subpatent infections from samples collected from three regions of northwest Ethiopia. Sub-samples of dried blood spots from the Ethiopian Malaria Indicator Survey 2015 (EMIS-2015) were tested and compared using microscopy, rapid diagnostic tests (RDTs), and nested polymerase chain reaction (nPCR) to determine the prevalence of subpatent infection. Paired seroprevalence results previously reported along with gender, age, and elevation of residence were explored as risk factors for Plasmodium infection. Of the 2608 samples collected, the highest positive rate for Plasmodium infection was found with nPCR 3.3% (95% CI 2.7-4.1) compared with RDT 2.8% (95% CI 2.2-3.5) and microscopy 1.2% (95% CI 0.8-1.7). Of the nPCR positive cases, Plasmodium falciparum accounted for 3.1% (95% CI 2.5-3.8), Plasmodium vivax 0.4% (95% CI 0.2-0.7), mixed P. falciparum and P. vivax 0.1% (95% CI 0.0-0.4), and mixed P. falciparum and Plasmodium malariae 0.1% (95% CI 0.0-0.3). nPCR detected an additional 30 samples that had not been detected by conventional methods. The majority of the nPCR positive cases (61% (53/87)) were from the Benishangul-Gumuz Region. Malaria seropositivity had significant association with nPCR positivity [adjusted OR 10.0 (95% CI 3.2-29.4), P < 0.001]. Using nPCR the detection rate of malaria parasites increased by nearly threefold over rates based on microscopy in samples collected during a national cross-sectional survey in 2015 in Ethiopia. Such subpatent infections might contribute to malaria transmission. In addition to strengthening routine surveillance systems, malaria programmes may need to consider low-density, subpatent infections in order to accelerate malaria elimination efforts.
Sections du résumé
BACKGROUND
BACKGROUND
Ethiopia has set a goal for malaria elimination by 2030. Low parasite density infections may go undetected by conventional diagnostic methods (microscopy and rapid diagnostic tests) and their contribution to malaria transmission varies by transmission settings. This study quantified the burden of subpatent infections from samples collected from three regions of northwest Ethiopia.
METHODS
METHODS
Sub-samples of dried blood spots from the Ethiopian Malaria Indicator Survey 2015 (EMIS-2015) were tested and compared using microscopy, rapid diagnostic tests (RDTs), and nested polymerase chain reaction (nPCR) to determine the prevalence of subpatent infection. Paired seroprevalence results previously reported along with gender, age, and elevation of residence were explored as risk factors for Plasmodium infection.
RESULTS
RESULTS
Of the 2608 samples collected, the highest positive rate for Plasmodium infection was found with nPCR 3.3% (95% CI 2.7-4.1) compared with RDT 2.8% (95% CI 2.2-3.5) and microscopy 1.2% (95% CI 0.8-1.7). Of the nPCR positive cases, Plasmodium falciparum accounted for 3.1% (95% CI 2.5-3.8), Plasmodium vivax 0.4% (95% CI 0.2-0.7), mixed P. falciparum and P. vivax 0.1% (95% CI 0.0-0.4), and mixed P. falciparum and Plasmodium malariae 0.1% (95% CI 0.0-0.3). nPCR detected an additional 30 samples that had not been detected by conventional methods. The majority of the nPCR positive cases (61% (53/87)) were from the Benishangul-Gumuz Region. Malaria seropositivity had significant association with nPCR positivity [adjusted OR 10.0 (95% CI 3.2-29.4), P < 0.001].
CONCLUSION
CONCLUSIONS
Using nPCR the detection rate of malaria parasites increased by nearly threefold over rates based on microscopy in samples collected during a national cross-sectional survey in 2015 in Ethiopia. Such subpatent infections might contribute to malaria transmission. In addition to strengthening routine surveillance systems, malaria programmes may need to consider low-density, subpatent infections in order to accelerate malaria elimination efforts.
Identifiants
pubmed: 32131841
doi: 10.1186/s12936-020-03177-w
pii: 10.1186/s12936-020-03177-w
pmc: PMC7057598
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
108Références
Trials. 2015 Mar 01;16:70
pubmed: 25887344
PLoS Med. 2015 Mar 03;12(3):e1001788
pubmed: 25734259
Clin Infect Dis. 2018 Jun 1;66(12):1883-1891
pubmed: 29304258
J Clin Microbiol. 2014 Sep;52(9):3303-9
pubmed: 24989601
Malar J. 2016 May 27;15(1):296
pubmed: 27234446
Malar J. 2016 Jan 08;15:17
pubmed: 26747132
Malar J. 2016 Feb 06;15:70
pubmed: 26852321
Malar J. 2018 Dec 19;17(1):480
pubmed: 30567537
PLoS One. 2014 Sep 19;9(9):e107693
pubmed: 25237812
Methods Mol Med. 2002;72:189-203
pubmed: 12125116
Malar J. 2015 Jan 28;14:43
pubmed: 25627037
Malar J. 2013 Oct 03;12:352
pubmed: 24090230
Sci Rep. 2017 Nov 7;7(1):14718
pubmed: 29116127
Lancet. 2010 Nov 6;376(9752):1592-603
pubmed: 21035841
PLoS Negl Trop Dis. 2015 May 21;9(5):e0003758
pubmed: 25996619
Am J Trop Med Hyg. 2009 Nov;81(5):763-7
pubmed: 19861607
Malar J. 2015 Aug 05;14:303
pubmed: 26242243
Malar J. 2015 Dec 21;14:510
pubmed: 26689195
Malar J. 2016 Apr 30;15:250
pubmed: 27129785
Malar J. 2016 Jan 28;15:48
pubmed: 26822406
Malar J. 2012 Apr 25;11:126
pubmed: 22533733
Malar J. 2012 Aug 21;11:288
pubmed: 22909399
Nat Commun. 2012;3:1237
pubmed: 23212366
PLoS One. 2018 Sep 7;13(9):e0203524
pubmed: 30192839
Malar J. 2019 Jul 22;18(1):246
pubmed: 31331340
Malar J. 2015 Jan 28;14:33
pubmed: 25627033
Malar J. 2017 Apr 4;16(1):138
pubmed: 28376883
Malar J. 2014 Dec 18;13:509
pubmed: 25522751
Malar J. 2010 Sep 07;9:254
pubmed: 20822506
Mol Biochem Parasitol. 1993 Apr;58(2):283-92
pubmed: 8479452
Iran J Parasitol. 2015 Jan-Mar;10(1):39-45
pubmed: 25904944
Nat Commun. 2019 Mar 29;10(1):1433
pubmed: 30926893
Emerg Infect Dis. 2018 Mar;24(3):462-470
pubmed: 29460730
Lancet Infect Dis. 2018 Aug;18(8):826-827
pubmed: 30064667