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.

Many cases of cutaneous leishmaniasis are observed during hospital consultations in Nouakchott. The objective of our study is to collect all cases of cutaneous leishmaniasis in Nouakchott and to study its epidemiological and clinico-biological characteristics.
METHODS: This is a prospective multicenter descriptive study conducted in two specialized hospital departments in Nouakchott from September 1st, 2016 to the end of October 2017. All patients with suspicious lesions of cutaneous leishmaniasis during this period were selected. Parasitological skin sampling, PCR and histology have been performed to patients.
RESULTS: Twenty one out of 9000 patients were diagnosed during the study period, with an average age of 23 years (ranging from 3 to 70 years). A male predominance was noted with a sex ratio of 2/1. The most frequent locations are the discovered parts of the body (the 4 members). The ulcero-crusty form is encountered in 2/3 of the cases. L. major is more frequently identified (61.9%) followed by L infantum in 23.8% of cases. Meglume Antimoniate was administered intralesionally in 57.1% of patients. In Nouakchott, cutaneous leishmaniasis is not uncommon. The cases observed are related to an origin or a stay in the southern regions.
De nombreux cas de leishmaniose cutanée sont observés lors des consultations hospitalières à Nouakchott. L\'objectif de notre étude est de recueillir tous les cas de leishmanioses cutanées à Nouakchott et d\'en étudier les caractéristiques épidémiologiques et clinico-biologiques.
UNASSIGNED: Il s\'agit d\'une étude multicentrique descriptive prospective réalisée dans 2 services hospitaliers spécialisés de Nouakchott du 1er septembre 2016 à la fin du mois d\'octobre 2017. Tous les patients présentant des lésions suspectes de leishmaniose cutanée durant cette période ont été retenus. Un prélèvement cutané à visée parasitologique, une PCR et une histologie ont été effectués aux patients.
UNASSIGNED: Vingt et un patients sur 9000 consultants ont été diagnostiqués durant la période d\'étude, avec un âge moyen de 23 ans (variant de 3 à 70 ans). Une prédominance masculine a été notée avec un sexe ratio de 2/1. Les localisations les plus fréquentes sont les parties découvertes du corps (les 4 membres). La forme ulcéro-crouteuse est rencontrée dans 2/3 des cas. L. major est plus fréquemment identifiée (61,9 %) suivi de L infantum dans 23,8% des cas. L\'Antimoniate de Meglume a été administré par voie intralésionnelle chez 57,1% des patients. A Nouakchott, la Leishmaniose cutanée n\'est pas rare. Les cas observés sont liés à une origine ou un séjour dans les régions du Sud.

The first outbreak of epidemic respiratory disease due to unknown etiology was reported in the Chinese city of Wuhan December 2019. The World Health Organization (WHO) firstly used the term \"new coronavirus 2019\" on December 29, 2019. This pandemic, which is currently called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a disease caused by SARS-CoV-2. It was subsequently called coronavirus disease 2019 (COVID-19) by the WHO. The purpose of this study was to determine the prevalence of antibodies against SARS-CoV-2 in all employees of the Nouakchott National Hospital Center (CHN). The study was conducted during the week 20/05/2020 to 27/05/2020. It involved 853 employees of all ranks (doctors, pharmacists, nurses, secretaries, security personnel, administrators...) of whom 504 were male and 331 were female, with a sex ratio of 1,52 with an average age of 39 years, ranging from 20 to 60 years. The screening for IgG and IgM antibodies to SARS-CoV-2 was performed using Biotime (Xiamen Biotime Biotechnology Co., Ltd.) immunochromatographic technique. Out of 835 employees included in our study, 14 were positive (1.67%) of whom 12 had IgM and IgG anti-SARS-CoV-2 antibodies and 2 had isolated IgM. Nasopharyngeal swab polymerase chain reaction (PCR) was performed in these 14 patients and was positive in six. While PCR is the gold standard for the diagnosis of SARS-CoV-2, serological tests for SARS-CoV-2 antibodies, in particular rapid tests (RDTs) are a diagnostic complement to COVID-19. They have the advantage of being easy to realize, of being safe both in the laboratories and outside the laboratories. RDTs enabled us to detect asymptomatic SARS-CoV-2 carriers within CHN employees. This allowed for patients management and isolation to protect patients and their environments.

Mycetoma is a chronic, progressive and destructive inflammatory disease that affects the skin, subcutaneous and other tissues. The objective of this study was to identify all cases of mycetoma diagnosed in three health facilities in Nouakchott, Mauritania during 2016-2018.
This retrospective hospital-based study was conducted at the Dermatology, Orthopedics, Mycology and Pathology departments of the National Hospital Center of Nouakchott, the Military Hospital of Nouakchott and the National Institute for Research in Public Health of Nouakchott.
Eighty-seven patients were included in this study. They comprised 65 male patients (74.71%) and 22 females (25.28%) with a gender ratio of 4:1. The mean age was 41.87 y and ages ranged from 14 to 70 y. The most common age group was 40-45 y (11%). The foot was the most frequently affected site seen in 60 patients (69%), followed by ankle and hand with 6 patients each (7%). In the study, 56 patients (64%) had regional lymphadenopathy. Forty-nine patients (56%) had bone involvement. Thirty-two patients (37%) had medical treatment. Twenty-seven patients (87%) received fluconazole and four patients (13%) had co-trimoxazole treatment.
The mycetoma patients seen in these three centres were mainly male farmers from rural areas. The lesions were seen mainly in the lower limbs and the majority had bone involvement radiologically.

Rotavirus vaccine was introduced in Mauritania in December 2014. We investigated hospitalizations with diarrhea during pre and post-vaccination periods among children aged 0-5 years in Nouakchott, the capital of Mauritania.
We conducted a retrospective review of hospital admission registries from November 1st 2012 through October 31th 2017 at all referral hospitals in Nouakchott. We described admissions of children aged 0-5 years by diagnosis, data of admission, age and sex, and compared the proportion of all childhood hospitalizations with diarrhea before and after rotavirus vaccine introduction.
In total, 6552 (19%) of all 34,329 hospitalizations in 0-5 year-olds had diarrhea. Of these, 3523/16,952 (20.7%) were recorded during the pre-vaccine period, 1373/6897 (19.9%) during the transition period (November 2014-October 2015), and 1656/10,480 (15.8%) during the post-vaccination period. The proportion of all childhood hospitalizations with diarrhea during the pre-vaccine period was 22.6% among males and 18.7% among females. Approximately one third (32.3%) of hospitalizations with diarrhea occurred in children aged 6-11 months. During the post-vaccination period, the proportion of hospitalizations with diarrhea declined by 24%, and the highest reduction (74%) was observed in children aged 2 to 5 years (P < 0.001).
The proportion of childhood hospitalizations with diarrhea in Nouakchott was reduced by about one fourth after introduction of rotavirus vaccination in Mauritania, indicating a major impact for public health for children in the capital city.

Aerosol optical depth (AOD) is a vital parameter that determines air quality over a geographic enclave. In this paper, the pollution state of Nouakchott-Mauritania was considered. Fifteen years primary (aerosol optical depth) dataset was obtained from the Multi-angle Imaging Spectro-Radiometer (MISR). The secondary datasets were generated from the primary dataset to understand the short and long term effect of aerosol loading over nouakchott. The dataset is important to resolve the ground effect of satellite measurements.

BACKGROUND: Mauritania is one of the African countries with ongoing malaria transmission where data on insecticide resistance of local malaria vectors are limited despite an increasing use of long-lasting insecticide-treated nets (LLINs) as the main intervention for vector control. This study presents an evaluation of the level of insecticide resistance of Anopheles arabiensis in Nouakchott.
METHODS: Anopheles gambiae (s.l.) larvae were collected in breeding sites during the rainy season (August-September) in 2015 and 2016 from two selected sites in Nouakchott and reared until emergence. Adult anopheline mosquitoes were tested against malathion (5%), bendiocarb (0.1%), permethrin (0.75%) and deltamethrin (0.05%) using standard World Health Organization (WHO) insecticide-impregnated papers. PCR assays were used for the identification of An. gambiae (s.l.) sibling species as well as knockdown resistance (kdr).
RESULTS: The mean knockdown times 50% (KDT50) and 95% (KDT95) were 66 ± 17 and 244 ± 13 min, respectively, for permethrin in 2015. The KDT50 and the KDT95 were 39 ± 13 and 119 ± 13 min, respectively, for deltamethrin. The KDT50 and the KDT95 doubled for both molecules in 2016. The mortality rates 24 h post-exposure revealed that An. arabiensis populations in Nouakchott were fully susceptible to bendiocarb and malathion in 2015 as well as in 2016, while they were resistant to permethrin (51.9% mortality in 2015 and 24.1% mortality in 2016) and to deltamethrin (83.7% mortality in 2015 and 39.1% mortality in 2016). The molecular identification showed that Anopheles arabiensis was the only malaria vector species collected in Nouakchott in 2015 and 2016. Both the West and East African kdr mutant alleles were found in An. arabiensis mosquitoes surviving exposure to pyrethroid insecticide, with a high rate of homozygous resistant genotypes (54.3% for the West African kdr mutation and 21.4% for the East African kdr mutation) and a significant departure from Hardy-Weinberg proportions (χ2 = 134, df = 3, P < 0.001).
CONCLUSIONS: The study showed high levels of pyrethroid resistance in An. arabiensis populations in Nouakchott and presence of both West and East African kdr alleles in the resistant phenotype. These results highlight a need for routine monitoring of susceptibility of malaria vector populations to insecticides used in public health programs.

BACKGROUND: Staphilococcus aureus is a leading pathogen for humans causing a variety of infections such as skin, urinary tract and lung infections as well as sepsis. This study aims to evaluate the susceptibility of community-acquired strains of Staphylococcus aureus, isolated from various pathological products, compared with major antibiotics used in Nouakchott Region (Mauritania).
METHODS: We conducted a retrospective study of 281 strains of Staphylococcus aureus strains isolated from various pathological products from non-hospitalized patients in the National referral hospital laboratory and in two private laboratories in the city of Nouakchott between January 2014 and August 2015. Antibiotic sensitivity was determined by disk diffusion method using agar containing Mueller-Hinton medium according to CA-SFM\'s recommendations.
RESULTS: The resistance rate to penicillin G was high (96-100%). Community-acquired MRSA rate was between 25 and 26% in suppurations, 34.3% in urine cultures and 28% in sperm cultures. Macrolide -Lincosamyne-streptogramins (MLS) resistance, giving rise to the phenotype MLSb inducible, was found in 6% of urinary strains and 27% of strains isolated from suppurations. The activity of aminoglycosides was variable, amikacin was active against all strains. Cotrimoxazole activity was low (77% had resistance) and no vancomycin resistance was reported.
CONCLUSIONS: The activity of penicillin G against Staphylococcus aureusstrains isolated in Nouakchott region is almost zero and community-acquired MRSA rate is high, accounting for 34%. This could be explained by uncontrolled use of these molecules in our country.

BACKGROUND: A urinary tract infection (UTI) is a frequent pathology in outpatients and admitted patients as well. In recent years, there has been an increase in the resistance of germs responsible for UTI to tested antibiotics, particularly because of the emergence of Enterobacteria secreting extended-spectrum beta-lactamase (ESBL).
OBJECTIVE: The aim of this work was to study the epidemiology of germs responsible for urinary tract infections and their antibiotic sensitivity at three clinical laboratories in the city of Nouakchott (Mauritania) in all patients presenting to these laboratories for urine culture during a period of six months.
METHODS: This is a prospective study conducted at three clinical laboratories in Nouakchott, over a period of six months from January 1st to June 30th 2014 for all patients coming to these laboratories for urinalysis test during this period. The culture was performed according to the usual techniques, and the antibiogram was done according to the recommendations of the Antibiogram Committee of the French Society of Microbiology. The statistical analysis was performed using SPSS Statistics 20.
RESULTS: From 3082 urine exam, 568 were positive, which means 18.4%. These infections were for hospitalized patients (17.8%) and outpatients in particular (82.2%). Sex ratio F/M was 1.6. The epidemiology of urinary tract infections in these three medical analysis laboratories is comparable to the past studies data regarding age, sex, and the bacteria, the most frequently responsible (Escherichia coli 64.4%). But differences in the resistance of E. coli are observed: higher resistance to beta-lactam antibiotics, the quinolones, the fluoroquinolones, and cotrimoxazol. UTI was common in patients with urinary catheter (64.9%), diabetics (52.4%), hospitalized patients (49.3%) and pregnant women (38.7%). The prevalence of urinary tract infections caused by Enterobacteria ESBL in our study was 12.8%, of all urinary tract infections caused by Enterobacteria; 10.4 and 20.4% of the E. coli and Klebsiella spp, respectively produced a ESBL.
CONCLUSIONS: The distribution of germs in our study is comparable to the literature, however, antibiotic resistance is higher in our study, which is probably a result of the inappropriate use of these drugs in our country, therefore it is important for us to create a good strategy to supply and distribute these drugs, as well as the review of the empirical treatment of UTI in our country.
METHODS: 4.