Mint Mohamed Lemine et al. Parasites & Vectors (2017) 10:35 DOI 10.1186/s13071-017-1978-y REVIEW Open Access Mosquitoes (Diptera: Culicidae) in Mauritania: a review of their biodiversity, distribution and medical importance Aichetou Mint Mohamed Lemine1,2, Mohamed Aly Ould Lemrabott1, Moina Hasni Ebou1,KhadijetouMintLekweiry1, Mohamed Salem Ould Ahmedou Salem1, Khyarhoum Ould Brahim1, Mohamed Ouldabdallahi Moukah1, Issa Nabiyoullahi Ould Bouraya3,CecileBrengues4, Jean-François Trape4, Leonardo Basco5, Hervé Bogreau5,6, Frédéric Simard4, Ousmane Faye2 and Ali Ould Mohamed Salem Boukhary1* Abstract Although mosquitoes (Diptera: Culicidae) are important disease vectors, information on their biodiversity in Mauritania is scarce and very dispersed in the literature. Data from the scientific literature gathered in the country from 1948 to 2016 were collected and analyzed. Overall 51 culicid species comprising 17 Anopheles spp., 14 Aedes spp., 18 Culex spp. and two Mansonia spp. have been described in Mauritania among which Anopheles arabiensis, Aedes vexans, Culex poicilipes and Culex antennatus are of epidemiological significance. Anopheles arabiensis is widely distributed throughout the country and its geographic distribution has increased northwards in recent years, shifting its northern limit form 17°32′N in the 1960s to 18°47′N today. Its presence in the central region of Tagant highlights the great ecological plasticity of the species. Conversely, the distribution of Anopheles gambiae (s.s.) and Anopheles melas has shrunk compared to that of the 1960s. Anopheles rhodesiensis and An. d’thali are mainly confined in the mountainous areas (alt. 200–700 m), whereas Anopheles pharoensis is widely distributed in the Senegal River basin. Culex poicilipes and Cx. antenattus were naturally found infected with Rift valley fever virus in central and northern Mauritania following the Rift valley outbreaks of 1998 and 2012. Recently, Ae. aegypti emerged in Nouakchott and is probably responsible for dengue fever episodes of 2015. This paper provides a concise and up-to-date overview of the existing literature on mosquito species known to occur in Mauritania and highlights areas where future studies should fill a gap in knowledge about vector biodiversity. It aims to help ongoing and future research on mosquitoes particularly in the field of medical entomology to inform evidence-based decision-making for vector control and management strategies. Keywords: Culicidae, Biodiversity, Mosquitoes, Vector, Rift Valley fever, Dengue, Malaria, Mauritania Background and YF are acute febrile mosquito-borne viral diseases of Mosquitoes (Diptera: Culicidae) are considered one of man and animals (RVF) which cause clinical syndromes the most relevant groups of arthropods in public health ranging from an uncomplicated form with fever to [1, 2]. Those belonging to the genera Aedes, Anopheles hemorrhagic disease in humans and abortions and and Culex are of interest because of their role in the mortality during epizootics in livestock [3]. Malaria, the transmission of a variety of human and animal diseases deadliest vector-borne parasitic disease worldwide, is such as Rift Valley fever (RVF), dengue fever (DF), yel- caused by a protozoan belonging to the genus Plasmo- low fever (YF), Zika, chikungunya and malaria. RVF, DF dium. According to the World Health Organization (WHO), vector-borne diseases account for 17% of the * Correspondence: [email protected] estimated global burden of all infectious diseases mostly 1Unité de recherche Génomes et Milieux, Jeune Equipe Associée à l’IRD due to malaria and DF [4]. (RI3M), Université de Nouakchott Al-Aasriya, Faculté des Sciences et Techniques, Nouveau Campus Universitaire, Nouakchott BP 5026, Mauritania Mosquitoes are dipterans of the suborder Nematocera, Full list of author information is available at the end of the article all placed within the family Culicidae. Approximately © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Mint Mohamed Lemine et al. Parasites & Vectors (2017) 10:35 Page 2 of 13 3500 species and subspecies in 44 genera are recognized of inhabitants) in the southern Sahelian region and along globally [5]. The cosmopolitan genera Anopheles with the Senegal River. Settlement of nomad populations and seven subgenera involving 460 recognized species, Culex rural exodus, partly related to the periods of drought in the with 26 subgenera comprising 763 species and the Old 1970s, 1980s and 1990s, are the most significant demo- World and Nearctic genus Aedes with 70 subgenera in- graphic phenomena that have occurred in Mauritania since cluding 927 species are the highest in species diversity the country’s independence in 1960. Whereas the propor- and most important for public health in the family [5, 6]. tion of urban population was 9% in 1965, it increased to Historically, five large outbreaks of RVF occurred in 22.7, 46.7 and 60% in 1977, 2005 and 2010, respectively. Mauritania in 1987, 1998, 2003, 2010 and 2012 resulting Over the same period, the nomad population rapidly in a high number of human fatalities and major losses in decreased from 65% in 1965 to 12, 6 and 2% in 1988, the livestock population [7–12]. Furthermore, the WHO 2000 and 2013, respectively [25]. Mauritania has a large outbreaks and emergencies bulletin reported DF and livestock population with 1,247,000 camels, 1,657,000 RVF events in Mauritania in 2015 [13]. Although in this cattle, 12,555,000 small ruminants (sheep and goats) bulletin, the areas in which these outbreaks have oc- and an important population of equines (donkeys and curred were not specified, data from the Mauritanian horses) estimated at 212,000 [26]. The livestock dens- Ministry of Health have cited Nouakchott, the capital ity is higher in southern Mauritania compared to that city and the southern Brakna region for DF and RVF, re- of its arid northern part. spectively (Ouldabdallahi Moukah, pers. comm.). Despite being largely arid, there are several temporary Moreover, malaria is endemic in the southern regions and permanent wetland areas in Mauritania. The most of the country and in parts of the Saharan region, in- important are the Senegal River Delta, the protected cluding Nouakchott, the capital city, where peak trans- coastal Banc d’Arguin National Park and the Diawling mission occurs in September and October during and National Park, the natural lakes of Aleg, Mal, Rkiz, mare shortly after the rainy season [14–17]. Approximately, de Kankoussa, mare de Mahmoude and more than 300 two-thirds of the resident population of Mauritania is oases [27, 28]. exposed to the risk of malaria. Mauritania is an arid country with two-thirds of its sur- In Mauritania, knowledge about the Culicidae fauna face area lying within the arid zone of the Saharan desert has been closely related to studies on human health, like (0–100 mm annual rainfall) and the remainder belongs to the malariometric surveys of 1942 during the colonial the Sahelian zone (100–500 mm annual rainfall). period [18] and those of 1960s to assess malaria epi- Rain is relatively scarce and irregular over the country. demiology [19–21] and more recently after the recurrent It falls between July and September, with an increased RVF outbreaks [9, 12, 22, 23]. It is worth noting that gradient from North to South, ranging from less than there are no published data on mosquitoes in the coun- 50 mm annually in the northern Saharan zone to 500 mm try for the period 1970–1990 probably because of the in parts of the southernmost region of Guidimagha (Fig. 2). prolonged period of drought in the 1970s and 1980s in Studies on the variability of rainfall in Mauritania showed a the Sahel [24] during which food security had become a significant decreasing trend in annual rainfall because of priority over public health in most Sahelian countries. prolonged drought of 1970–1990. For instance, in the Although mosquitoes are important disease vectors, Sahelian southern part of the country, average rainfall de- information on mosquito biodiversity in Mauritania is creased by 120 mm (39%) between the periods 1933–1969 scarce and notably dispersed in the literature. Therefore, (310 mm) and 1970–1999 (190 mm) [29] which resulted in there is an urgent need for more detailed understanding a southward movement of 250 and 500 mm rainfall isohy- of the biodiversity, distribution and ecology of mosquito etal lines as reported by Mahé et al. [30] (Fig. 2). However, species known to occur in the country. This paper pro- it is not yet clear whether the unusual heavy rainfalls that vides the first comprehensive review on mosquitoes in occurred in the last decade, particularly in 2003, 2006, 2010 Mauritania and analyses data collected from the scien- and 2013, are signs of the establishment of sustainable wet- tific literature and published reports available within the ter conditions as suggested by De Longueville et al. [31]. country. Mean annual temperatures over the country range from 20 °C in January to 33.7 °C in June. According to Salient data on Mauritania McSweeney et al. [32], the mean annual temperature in Mauritania (15°–27° N latitude and 5°–17° W longitude) Mauritania has increased by 0.9 °C since 1960, with an is in northwest Africa at the intersection of the Maghreb average rate of 0.19 °C per decade. region and sub-Saharan West Africa (Fig. 1). It covers an area of 1,030,700 km2, and has a population of Culicidae fauna in Mauritania 3,378,250, and a mean population density of 3.3 persons/ Overall, 51 mosquito species belonging to four genera km2.