Malaria in three epidemiological strata in Mauritania

Abstract

BackgroundMalaria epidemiology in Mauritania has been characterized on the basis of epidemiological strata, defined by climatic and geographic features, which divide the country into three zones: Sahelian zone, Sahelo-Saharan transition zone, and Saharan zone. The association between geographic stratification and malaria transmission was assessed through a series of parasitological and entomological surveys.MethodsSurveys were conducted during the ‘cool’ dry season in 2011, ‘hot’ dry season in 2012, and rainy season in 2013 in a total of 12 sentinel sites. Finger-prick capillary blood samples were collected from children aged 2–9 years old in randomly selected households for microscopic examination and rapid diagnostic test for malaria. Adult mosquitoes were sampled by pyrethrum spray catch and CDC light traps and identified using morphological keys and molecular tools.ResultsOf 3445 children included, 143 (4.15 %) were infected with malaria parasites including Plasmodium falciparum (n = 71, 2.06 %), Plasmodium vivax (57, 1.65 %), P. falciparum-P. vivax (2, 0.06 %), Plasmodium ovale (12, 0.35 %), and Plasmodium malariae (1, 0.03 %). A large majority of P. falciparum infections were observed in the Sahelo-Saharan zone. Malaria prevalence (P < 0.01) and parasite density (P < 0.001) were higher during the rainy season (2013), compared to cool dry season (2011). Plasmodium vivax was mainly observed in the Saharan region [43 of 59 (73 %) P. vivax infections], mostly in Nouakchott districts, with no significant seasonal variation. Of 3577 mosquitoes captured, 1014 (28.3 %) belonged to Anopheles spp. Anopheles gambiae was the predominant species in all three epidemiological strata during the ‘cool’ dry season in 2011 but was absent in all study sites, except for Teyarett district in Nouakchott, during the ‘hot’ dry season in 2012. During the rainy season in 2013, An. gambiae, Anopheles arabiensis, Anopheles pharoensis, and Anopheles rufipes were abundant in different zones.ConclusionsThe results of the present study support the stratification of malaria in Mauritania. However, the Sahelian zone had the lowest malaria prevalence, while the Sahelo-Saharan zone had the highest malaria burden. Local changes due to anthropogenic factors (i.e., human migration, urbanization, malaria interventions) should be considered in order to optimize the control strategy.

Characterization of Plasmodium falciparum genes associated with drug resistance in Hodh Elgharbi, a malaria hotspot near Malian–Mauritanian border

“…One recent study failed to detect P. vivax along the Malian–Mauritanian border (Selibaby, Ould Yenge, Aioun, Kobeni, Timbedra, Nema) [30]. However, the results of other studies, including the present study, indicate the presence of P. vivax in this hotspot [15, 16, 31]. A coordinated regional malaria control programme will be required in the effort to control cross-border malaria that involves both P. falciparum and P. vivax [32].…”

Mosquitoes (Diptera: Culicidae) in Mauritania: a review of their biodiversity, distribution and medical importance

“…domicola were recently reported by Ouldabdallahi Moukah et al [48] in Boghé (Brakna region) and Gouraye (Guidimagha region) located on the Senegal River. This species was already reported in Barkedji and Kédougou in Senegal [49].…”

“…gambiae (A, L) An. gambiae (A, L)Asb, Brk, Grg, Hch, Hgh, Trz[9, 18, 22, 35, 36, 42, 43, 47, 48] An. melas (A)Trz[20, 33] An.…”

“…pharoensis (A, L) An. pharoensis (A, L)Adr, Asb, Brk, Grg, Hgh, Trz, Tag[8, 9, 18, 20, 22, 23, 35, 41–44, 47, 48] An. pretoriensis (L) An.…”

Seasonal abundance, blood meal sources and insecticide susceptibility in major anopheline malaria vectors from southern Mauritania

“…In Mauritania, malaria is endemic with unstable seasonal transmission and 181,000 presumed and confirmed cases reported in 2015 [ 2 ]. Malaria infections are mainly due to Plasmodium falciparum which prevails in the southern Sahelian zone [ 3 – 5 ], whereas P. vivax is most widespread in the Northern Saharan zone, including Nouakchott, the capital city [ 3 , 6 ]. Studies conducted in Mauritania indicate that seventeen Anopheles species have been recorded throughout the country out of which four are considered as primary vectors and four as secondary vectors of malaria in Africa [ 7 ].…”