Genomic Characterization of SARS-CoV-2 Variants from Clinical Isolates during the COVID-19 Epidemic in Mauritania.

The rapid genetic evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the coronavirus disease 2019 (COVID-19) pandemic has greatly challenged public health authorities worldwide, including in Mauritania. Despite the presence of the virus in Mauritania, only one study described its genomic variation during the course of the epidemic. The purpose of the present study was to document the genomic pattern of SARS-CoV-2 variants from clinical isolates during the COVID-19 outbreak in Mauritania, from September to November 2021. The whole genomes from 54 SARS-CoV-2 strains detected in nasopharyngeal swabs with a cycle threshold value ≤ 30 were successfully sequenced using next-generation sequencing (NGS) and the Illumina protocol. The mean genome coverage (±standard deviation) was 96.8% (±3.7). The most commonly identified clade was 21J (57.4%), followed by 21D (16.7%), 20A (11.1%), and 20B (9.2%). At the level of lineages, the majority of the samples were Delta variants with the sub-lineage AY.34 (or B.1.617.2.34). Among the 54 SARS-CoV-2 isolates that were successfully sequenced, 33 (61.1%) came from vaccinated individuals, and 21 (38.9%) were from unvaccinated individuals. Several SARS-CoV-2 variants were present in Mauritania between September and November 2021. As Mauritania, like many West African countries, is resource-limited regarding viral genome sequencing facilities, establishment of mutualized sub-regional sequencing platforms will be necessary to ensure continuous monitoring of mutations in viral genomes and track potential reduction in COVID-19 vaccine efficacy, increased transmissibility, and disease severity.

Dietary diversity and its determinants among women of reproductive age residing in the urban area of Nouakchott, Mauritania.

BACKGROUND: The intake of nutrient-rich foods from diverse diets ensures adequate nutrition for women. This study aims to determine dietary diversity among women of reproductive age (WRA) using the MDD-W indicator and how it relates to their socio-economic characteristics in the city of Nouakchott, Mauritania. METHODS: A community-based cross-sectional study was conducted on 240 women of reproductive age, aged 15-49 years. Food consumption data were obtained through unquantified 24 h recall which is designed to identify all foods consumed by the women during this period. We computed MDD-W as the consumption of at least five out of ten predefined food groups according to the guideline of the Food and Agriculture Organization (FAO) of the United Nations. In order to determine which factors had a statistically significant influence on dietary diversity among women, we used a value of P < 0.05. RESULTS: The mean of dietary diversity was 5.48 and 71.7% of WRA had an acceptable minimum dietary diversity. During the study period, 96.25% and 80% of women consumed vitamin A and iron-rich foods respectively. The consumption rate of starchy foods, vitamin A-rich fruits and vegetables, meat, fish and chicken, milk and dairy products, dark green leafy vegetables and finally other vegetables was higher; 99.6%, 75.3%, 80%, 62.5%, 60.4% and 83.3% respectively. On the other hand, the consumption of legumes, eggs and other fruits was low; at 21.7%, 14.2% and 13.8% respectively. CONCLUSIONS: The study showed that more than half of the studied population had an acceptable minimum dietary diversity. The diet was mainly based on the consumption of starchy foods, meat and other vegetables than those rich in vitamin A.

Determinants of health insurance coverage among women in Mauritania: a multilevel analysis.

BACKGROUND: Health insurance has been documented as one of the primary methods of financing healthcare for Sustainable Development Goals (SDGs) by 2030. Yet, there is a dearth of evidence on the determinants of health insurance coverage among women in Mauritania. We examine the factors associated with health insurance coverage among women in Mauritania using a nationally representative survey dataset. METHODS: We analyzed secondary data from the 2019-2021 Mauritania Demographic and Health Survey. A weighted sample of 15,714 women of reproductive age (15-49 years) was included in the study. Multilevel regression analysis was used to examined the factors associated with health insurance coverage. The results were presented using an adjusted odds ratio (aOR) with a 95% confidence interval (CI). RESULTS: The coverage of health insurance among women was 8.7%. The majority of the women subscribed to social security health insurance (7.6%). Women aged 35 years and above [aOR = 1.54; 95% CI = 1.24, 1.92] were more likely to be covered by health insurance relative to those aged 15-24. The likelihood of being covered by health insurance increased with increasing level of education with the highest odds among women with higher education [aOR = 6.09; 95% CI = 3.93, 9.42]. Women in the richest wealth index households [aOR = 22.12; 95% CI = 9.52, 51.41] and those with grand parity [aOR = 2.16; 95% CI = 1.62, 2.87] had the highest odds of being covered by health insurance. Women who were working, those who watched television, and those who used the internet were more likely to be covered by health insurance relative to their counterparts who were not working, those who did not watch television, and those who did not use the internet. Women residing in Tiris zemour et Inchiri [aOR = 3.60; 95%CI = 1.60, 8.10], Tagant (aOR = 3.74; 95% CI = 1.61, 8.68], and Adrar [aOR = 2.76; 95% CI = 1.36, 5.61] regions were more likely to be covered by health insurance compared with those from Hodh Echargui. CONCLUSION: Health insurance coverage among the women in our study was low. Achieving the SDG targets of ensuring universal health coverage and lowering maternal mortality to less than 70 deaths per 100,000 live births requires the implementation of interventions to increase health insurance coverage, taking into consideration the identified factors in the study. We recommend effective public education and awareness creation on the importance of being covered by health insurance by leveraging television and internet platforms. Also, interventions to increase health insurance coverage should consider younger women and those in rural areas.

Conditions for health system resilience in the response to the COVID-19 pandemic in Mauritania.

INTRODUCTION: A country's ability to manage a crisis depends on its level of resilience. Efforts are made to clarify the concept of health system resilience, but its operationalisation remains little studied. In the present research, we described the capacity of the local healthcare system in the Islamic Republic of Mauritania, in West Africa, to cope with the COVID-19 pandemic. METHODS: We used a single case study with two health districts as units of analysis. A context analysis, a literature review and 33 semi-structured interviews were conducted. The data were analysed using a resilience conceptual framework. RESULTS: The analysis indicates a certain capacity to manage the crisis, but significant gaps and challenges remain. The management of many uncertainties is largely dependent on the quality of the alignment of decision-makers at district level with the national level. Local management of COVID-19 in the context of Mauritania's fragile healthcare system has been skewed to awareness-raising and a surveillance system. Three other elements appear to be particularly important in building a resilient healthcare system: leadership capacity, community dynamics and the existence of a learning culture. CONCLUSION: The COVID-19 pandemic has put a great deal of pressure on healthcare systems. Our study has shown the relevance of an in-depth contextual analysis to better identify the enabling environment and the capacities required to develop a certain level of resilience. The translation into practice of the skills required to build a resilient healthcare system remains to be further developed.

First report of kdr mutations in the voltage-gated sodium channel gene in the arbovirus vector, Aedes aegypti, from Nouakchott, Mauritania.

BACKGROUND: Since 2014, dengue epidemics have occurred almost annually in Nouakchott, the capital city of Mauritania, coinciding with the recent establishment of Aedes aegypti, the primary vector of dengue, in the city. Anopheles arabiensis, the primary vector of malaria, is also abundant not only in Nouakchott but also in most areas of the country. Resistance to insecticides has been studied in An. arabiensis but not in Ae. aegypti in Mauritania. The objective of the present study was to establish the baseline data on the frequencies of knockdown resistance (kdr) mutations in the voltage-gated sodium channel (vgsc) gene in Ae. aegypti collected in Nouakchott to improve vector control. METHODS: Resting Ae. aegypti mosquitoes were collected in 2017 and 2018 in Teyarett and Dar Naim districts in Nouakchott using a battery-powered aspirator. Polymerase chain reaction (PCR) and DNA sequencing were performed to detect the presence of five kdr mutations known to be associated with pyrethroid resistance: L982W, S989P, I1011M/G, V1016G/I, and F1534C. RESULTS: A total of 100 female Ae. aegypti mosquitoes were identified among collected resting culicid fauna, of which 60% (60/100) were unfed, 12% (12/100) freshly blood-fed, and 28% (28/100) gravid. Among the mutations investigated in this study, 989P, 1016G, and 1534C were found to be widespread, with the frequencies of 0.43, 0.44, and 0.55, respectively. Mutations were not found in codons 982 and 1011. No other mutations were detected within the fragments analyzed in this study. Genotype distribution did not deviate from Hardy-Weinberg equilibrium. The most frequent co-occurring point mutation patterns among Ae. aegypti mosquitoes were the heterozygous individuals 989SP/1016VG/1534FC detected in 45.1% of mosquitoes. In addition, homozygous mutant 1534CC co-occurred simultaneously with homozygous wild type 989SS and 1016VV in 30.5% of mosquito specimens. Inversely, homozygous wild-type 1534FF co-occurred simultaneously with homozygous mutant 989PP and 1016GG in 19.5% of the mosquitoes. CONCLUSIONS: To our knowledge, this is the first study reporting the presence of three point mutations in the vgsc gene of Ae. aegypti in Mauritania. The findings of the present study are alarming because they predict a high level of resistance to pyrethroid insecticides which are commonly used in vector control in the country. Therefore, further studies are urgently needed, in particular phenotypic characterization of insecticide resistance using the standardized test.

Risk factors associated with Crimean-Congo hemorrhagic fever virus circulation among human, livestock and ticks in Mauritania through a one health retrospective study.

BACKGROUND: Crimean Congo hemorrhagic fever (CCHF) is endemic in Southern Mauritania where recurrent outbreaks have been constantly observed since the 1980's. The present study is the first to assess CCHFV antibodies and RNA in humans. METHODS: A retrospective study was conducted using 263 humans and 1380 domestic animals serum samples, and 282 tick specimens of Hyalomma genus collected from 54 settings in 12 provinces across Mauritania. Antibodies targeting CCHF viral nucleoprotein were detected in animal and human sera using double-antigen ELISA. CCHFV specific RNA was detected in human and animal sera as well as tick supernatants using a CCHFV real time RT-PCR kit. Individual characteristics of sampled hosts were collected at the same time and data were geo-referenced. Satellite data of several environmental and climatic factors, were downloaded from publicly available datasets, and combined with data on livestock mobility, animal and human density, road accessibility and individual characteristics to identify possible risk factors for CCHFV spatial distribution. To this end, multivariate logistic models were developed for each host category (human, small and large ruminants). RESULTS: The overall CCHFV antibody prevalence was 11.8% [95% CI: 8.4-16.3] in humans (17.9% in 2020 and 5.4% in 2021; p = 0.0017) and 33.1% (95% CI: 30.1-36.3) in livestock. CCHFV-specific antibodies were detected in 91 (18.1%) out of 502 sheep, 43 (9.0%) out of 477 goats, 144 (90.5%) out of 161 dromedaries and 179 (74.6%) out of 240 cattle. CCHFV RNA was detected in only 2 (0.7%) sera out of 263 animals herders samples from Hodh El Gharbi province and in 32 (11.3%) out of 282 Hyalomma ticks. In humans as well as in animals, seropositivity was not associated with sex or age groups. The multivariate analysis determined the role of different environmental, climatic and anthropic factors in the spatial distribution of the disease with animal mobility and age being identified as risk factors. CONCLUSION: Results of the present study demonstrate the potential risk of CCHF for human population in Mauritania primarily those living in rural areas in close vicinity with animals. Future studies should prioritize an integrative human and veterinary approach for better understanding and managing Crimean-Congo hemorrhagic fever.

Mercury distribution in fish organs sampled along the Mauritanian Atlantic coast and their potential human health risks.

This paper aimed at assessing total mercury concentration in seven common fish species (Auxis rochei, Caranx rhonchus, Sardina pilchardus, Sardinella aurita, Sardinella maderensis, Scomber colias and Trachurus trecae) and a relationship between Hg organotropism and food regimes along the Mauritanian Atlantic coast. Results show that total mercury concentration in fish collected along five sites ranged from 0.027 to 0.533 mg/kg dry weight. Significant differences were observed among species depending on feeding behavior. Muscle tissues of carnivorous fish presented significantly higher levels of total mercury than that of omnivorous fish, except for Scomber colias, suggesting mercury biomagnification through the food chain. Significant differences in mercury concentrations were observed between muscle tissues and liver, for Auxis rochei, Trachurus trecae, and Caranx rhonchus. The mean concentrations in the different species are however low and none of the concentration values exceed the World Health Organization's threshold for human consumption.

Molecular Characterization of Erythrocyte Glucose-6-Phosphate Dehydrogenase Deficiency in Different Ethnic Groups of Blood Donors in Mauritania.

BACKGROUND: Glucose-6-phosphate-dehydrogenase (G6PD) deficiency is the most frequent enzymopathy worldwide; it is a genetic disorder that affects red blood cells and causes hemolysis. Here, we conducted a study on G6PD-deficient subjects in Mauritania to evaluate the molecular characteristics associated with a deficiency in this enzyme and the frequency of nucleotide polymorphisms in the glucose-6-phosphate dehydrogenase gene. METHOD AND MATERIALS: A total of 943 blood samples were collected from blood donors (803 males and 140 females; 364 white Moors; 439 black Moors; 112 Pulaar; 18 Wolof; 10 Soninke). All blood samples were analyzed using a rapid screening test. G6PD status was analyzed quantitatively by the Randox G6PD test. Samples deficient in G6PD were extracted from the whole blood samples and subjected to DNA genotyping. The most frequent G6PD variants were determined by two molecular techniques: restriction fragment length polymorphism (RFLP) and multiplex PCR using the GENESPARK G6PD African kit. A total of six single nucleotide polymorphisms (SNPs) (G202A, A376G, A542T, G680T, C563T, and T968C) were identified. RESULTS: The prevalence of G6PD deficiency in this population sample was 8.1%. The most common mutation was A376G/202A and was characterized by the G6PD A-phenotype, which is more common in the G6PD-deficient black Moors population. The wilaya in Nouakchott was the most affected among the 13 wilayas studied. CONCLUSIONS: This study shows, for the first time, the presence of the G680T mutation.

Macro- and trace elements in plants from Mauritania and risk assessment.

This study aimed to determine the content of elemental levels of eight plants species originating from Mauritania and used as medicinal plant and to assess their risk for human health. The range of elemental content in the studied plant parts of these plant species were 0.51-16.1 mg/g for Ca, 2.63-6.49 mg/g for Mg, 11.2-201 µg/g for Al, 6.5-28.2 µg/g for Zn, 5.6-453 µg/g for Fe, 1.1-6.4 µg/g for Ni, 11.0-302 µg/g for Mn and 0.7-9.0 µg/g for Cu. The Cr, Pb, Cd and Co levels were below the limits of detection in all samples. The estimated weekly intake (EWI) and target hazard quotient (THQ) were calculated. Except for Al the THQ values were below 1, so it could be concluded that these plant species have low probability of causing non-cancer health problems for the consumer.

[Analysis of national leprosy surveillance data in Mauritania from 2009 to 2019]. / Analyse des données nationales de surveillance de la lèpre en Mauritanie de 2009 à 2019.

Introduction: Leprosy is a chronic infectious disease that mainly affects the skin, mucous membranes and the peripheral nervous system. Its elimination as a public health problem seems to lead to its ignorance and therefore to a risk of late diagnosis. An analysis of leprosy surveillance data in Mauritania was conducted to determine epidemiological trends and clinical forms of reported cases. Material and method: The retrospective study was based on the epidemiological records of leprosy in Mauritania from 2009 to 2019. The diagnosis of leprosy was made on the basis of the diagnostic criteria of the World Health Organization (WHO). Data were analyzed using Epi Info version 7.2.5.0. The frequencies, proportions, and rates were calculated. Results: Over the past 11 years, 164 cases have been notified. Among the notified cases, 96/164 (58.5%) were males and 68/164 (41.5%) females, with a sex ratio of 1.4. The mean age (± standard deviation) was 44.0 ± 17.1 years [range, 9 - 86 years], and the median was 45 years [interquartile range, 32.5; 57.5]. Children under the age of 16 accounted for 9/164 (5.5%). The wilayas (i.e. "regions") of Nouakchott were the most endemic regions in the country. The multibacillary form (MB) represented 109/164 (66.5%) cases among the observed clinical forms. The average annual incidence was 0.3 case/100,000 population for MB and 0.1 case/100,000 for PB (paucibacillary). All reported cases were treated with multidrug therapy. Conclusion: The results of leprosy surveillance showed a persistence of this disease in Mauritania. It is necessary to relaunch leprosy services at all levels in order to continue to reduce the morbidity associated with this disease, and eventually eliminate it from the country.

Diversity of Rickettsia spp. in ticks from wild mammals of Morocco and Mauritania.

Ticks are known as vectors and reservoirs of rickettsiae and, wildlife vertebrate hosts as suitable dispersers of ticks contributing to the life cycle of rickettsial agents in nature. In the herein study, the presence of rickettsiae was investigated in ticks from wild mammals (Gerbillus and Jaculus, Vulpes rueppellii, Canis anthus, Felis lybica and Felis margarita) in Mauritania and Morocco. Morphological and molecular analysis of ticks allowed their identification as Rhipicephalus sanguineus sensu lato and Hyalomma impeltatum. A total of 126 partially engorged adult ticks, collected from 40 animals, were screened for the presence of rickettsial DNA by conventional PCR targeting the ompB gene, followed by ompA and gltA targets and bidirectional sequencing. As a result of the sequence analyses, that at least three different species of pathogenic spotted fever group rickettsiae were detected. Rickettsia parkeri-like was detected in a R. sanguineus s.l. (n=1) collected from an African wildcat from Morocco. Rickettsia aeschlimannii was detected in a H. impeltatum (n=1) collected from a gerbil rodent. Rickettsia massiliae was detected in R. sanguineus s.l. ticks (n=5) collected from two Ruppells' foxes. The herein study demonstrates that pathogenic Rickettsia species are circulating in Morocco and Mauritania wildlife.

Seroprevalence of Alphaviruses (Togaviridae) among Urban Population in Nouakchott, Mauritania, West Africa.

The presence of alphaviruses, such as chikungunya virus (CHIKV), has never been reported in Mauritania. We assessed the seroprevalence of CHIKV among Nouakchott residents. A cross-sectional study involving 1300 non-febrile patients consulting at the Nouakchott hospital center was conducted between January and June 2021. The presence of anti-CHIKV IgG and neutralizing antibodies against CHIKV, O'nyong-nyong virus (ONNV), and Semliki Forest virus (SFV) was determined by an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization test, respectively, and the associated risk factors were investigated. Of the 1300 study participants, serological evidence of previous exposure to CHIKV was observed in 37 individuals (2.8%). Sex, age, reported use of repellants, and bed net ownership and usage were not associated with CHIKV seropositivity. Our results showed the co-circulation of two other alphaviruses, ONNV and SFV, in Nouakchott in 30 (2.3%) individuals. This is the first study that documents the co-circulation of CHIKV, ONNV, and SFV in Mauritania, albeit at low prevalence. Surveillance and routine testing for alphaviruses and other arboviruses in symptomatic patients should be implemented in health facilities to assess the health burden associated with these viruses. Efforts should also be made to strengthen the vector control measures.

Malaria prevalence in Mauritania: a systematic review and meta-analysis.

BACKGROUND: Understanding malaria epidemiology is a critical step toward efficient malaria control and elimination. The objective of this meta-analysis was to derive robust estimates of malaria prevalence and Plasmodium species from studies conducted in Mauritania and published since 2000. METHODS: The present review followed the PRISMA guidelines. Searches were conducted in various electronic databases such as PubMed, Web of Science, and Scopus. To obtain pooled prevalence of malaria, meta-analysis was performed using the DerSimonian-Laird random-effects model. Methodological quality of eligible prevalence studies was assessed using Joanna Briggs Institute tool. Inconsistency and heterogeneity between studies were quantified by the I2 index and Cochran's Q test. Publication bias was assessed with funnel plots and Egger's regression tests. RESULTS: A total of 16 studies with a good individual methodological quality were included and analysed in this study. The overall random effects pooled prevalence of malaria infection (symptomatic and asymptomatic) across all included studies was 14.9% (95% confidence interval [95% CI]: 6.64, 25.80, I2 = 99.8%, P < 0.0001) by microscopy, 25.6% (95% CI: 8.74, 47.62, I2 = 99.6%, P < 0.0001) by PCR and 24.3% (95% CI: 12.05 to 39.14, I2 = 99.7%, P < 0.0001) by rapid diagnostic test. Using microscopy, the prevalence of asymptomatic malaria was 1.0% (95% CI: 0.00, 3.48) against 21.46% (95% CI: 11.03, 34.21) in symptomatic malaria. The overall prevalence of Plasmodium falciparum and Plasmodium vivax was 51.14% and 37.55%, respectively. Subgroup analysis showed significant variation (P = 0.039) in the prevalence of malaria between asymptomatic and symptomatic cases. CONCLUSION: Plasmodium falciparum and P. vivax are widespread in Mauritania. Results of this meta-analysis implies that distinct intervention measures including accurate parasite-based diagnosis and appropriate treatment of confirmed malaria cases are critical for a successful malaria control and elimination programme in Mauritania.