Cheikh Sokhna

• PhD
• Institute of Research for Development

Background Although Senegal's Universal Health Coverage (UHC) program has improved access to care, it has sometimes led to overuse of health services. Moreover, the program's substantial financial debt to health facilities (HFs) has exposed them to organizational and financial problems, making it difficult to renew drug stocks and pay salaries on t...

Acute respiratory infections (ARI) are a health priority, especially in countries with limited resources. They are a major cause of morbidity and mortality, especially among children and the elderly. In Senegal, the endemic circulation of respiratory viruses other than influenza has been demonstrated. However, there is a paucity of data exploring t...

Introduction Expanding health insurance is viewed as a core strategy for achieving universal health coverage. In Senegal, as in many other developing countries, this strategy has been implemented by creating community-based health insurance (CBHI) schemes with voluntary enrolment and a fixed premium paid by enrollees. Yet little is known about how...

Seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine and amodiaquine is recommended by the World Health Organization since 2012 for clinical malaria prevention in children in the Sahelian region of Africa. In Senegal, SMC implementation began in 2013 and is given to children under 10 years old. This study aimed to describe clinical...

Background: In Dielmo, Senegal, a rigorous implementation and close monitoring of control interventions have been keys to witness a significant reduction of all malaria indicators in the longitudinal cohort established since 1990. However, low-level malaria transmission persists, attributed partly to the asymptomatic human reservoir that potentiall...

The emergence and multiplication of multi-resistant microbes is becoming a major concern in medicine and scientific research, requiring an integrated, global approach to prevent their spread and develop new therapeutic solutions. Klebsiella pneumoniae can cause a variety of infections. It has several distinctive features, such as extended-spectrum...

Background: Limited data on malaria morbidity among African adults exposed since birth to intense malaria transmission are available. This study aimed to investigate malaria morbidity determinants among adults living in Dielmo village, Senegal, where a longitudinal epidemiological study was carried out over an 18-year period before the introduction...

Over the past 12 years, culturomics, a high-throughput culture method, has been developed, considerably widening the repertoire of known cultured bacteria. An exhaustive database, including a list of microbes isolated by culture from human skin, was recently established by performing a review of the literature. The aim of the present study was to u...

Background Freshwater snails are the first obligatory intermediate hosts in the trematode life cycle. Several parasitic diseases transmitted by these snails are endemic in Africa, and their distribution closely follows that of the intermediate hosts. These diseases represent a major public health problem and cause significant socio-economic losses...

Background Pilgrimages and travel to religious Mass Gatherings (MGs) are part of all major religions. This narrative review aims to describe some characteristics, including health risks, of the more well known and frequently undertaken ones. Methods A literature search was conducted using keywords related to the characteristics (frequency of occur...

Background Healthcare delivery in Senegal is hindered by a limited, unequally distributed healthcare workforce, and by inadequate infrastructure which negatively impact access to quality care and good health outcomes. Despite efforts to improve healthcare delivery through Universal Health Coverage (UHC), progress remains insufficient. We investigat...

Acute respiratory tract infections are one of the leading causes of morbidity and mortality worldwide. More data are needed on circulating respiratory microorganisms in different geographical areas and ecosystems. We analyzed nasopharyngeal swabs from 500 febrile patients living in the Niakhar area (Senegal), using FTDTM multiplex qPCR and simplex...

Overall prevalence of nasopharyngeal methicillin-resistant Staphylococcus aureus (MRSA) carriage in Grand Magal de Touba pilgrims was 5.2% by PCR and 2.6% acquired carriage following participation in the event. Given the potential for globalization of pathogens, surveillance is crucial to implementing timely interventions and protecting public heal...

Background Schistosomiasis remains a public health concern worldwide. It is responsible for more than 240 million cases in 78 countries, 40 million of whom are women of childbearing age. In the Senegal River basin, both Schistosoma haematobium and Schistosoma mansoni are very prevalent in school-age children. However, there is a lack of information...

Background Transmission of SARS-CoV-2 at major mass gatherings (MGs) has been observed during the COVID-19 pandemic. Methods In this systematic review done according to the PRISMA guidelines, PubMed and Scopus databases were searched for relevant studies to describe the epidemiology of SARS-CoV-2 in relation to major religious MGs including the Gr...

Bulinus snails surviving drought play a key role in the seasonal transmission of urogenital schistosomiasis, although our knowledge of their adaptation to dry season is still limited. We investigated the survival dynamic and infestation by the Schistosoma haematobium of Bulinus snails during the dry and rainy seasons in a single pond in an area of...

Background: In Dielmo, Senegal, a rigorous implementation and close monitoring of control interventions have been keys to witness a significant reduction of all malaria indicators in the longitudinal cohort established since 1990. However, low-level malaria transmission persists, attributed partly to the asymptomatic human reservoir that potentiall...

Seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine and amodiaquine is recommended by the World Health Organization since 2012 for clinical malaria prevention in children in the Sahelian region of Africa. In Senegal, SMC implementation began in 2013 and is given to children under 10 years old. This study aimed to describe clinical...

Morphological and MALDI-ToF MS identification of freshwater snail intermediate hosts of trematodes collected in Senegal.

Bulinus snails surviving drought play a key role in seasonal transmission of urogenital schistosomiasis although our knowledge of their adaptation to dry season is still limited. We investigated the survival dynamic and infestation by Schistosoma haematobium of Bulinus snails during the dry and rainy seasons in a single pond in an area of seasonal...

Background The epidemic rebounds observed in 2010 and 2013 in Dielmo, a Senegalese village, during a decade (2008–2019) of universal coverage using a long-lasting insecticidal net (LLIN) strategy could have contributed to the resurgence of malaria. Thus, this study was undertaken to understand the implications of net ownership and use on malaria re...

Treponematoses encompass a group of chronic and debilitating bacterial diseases transmitted sexually or by direct contact and attributed to Treponema pallidum. Despite being documented since as far back as 1963, the epidemiology of treponematoses in wild primates has remained an uninvestigated territory due to the inherent challenges associated wit...

Résumé Objectif Déterminer l’étiologie des infections cervico-vaginales par la cytobactériologie et l'efficacité de la qPCR pour le diagnostic des souches sensibles telles que Streptococcus agalactiae, Borrelia crocidurae, Chlamydia trachomatis, Neisseria gonorrhoeae et Treponema pallidum. Méthodologie Étude prospective transversale effectuée ent...

Background Freshwater snails of the genera Bulinus spp., Biomphalaria spp., and Oncomelania spp. are the main intermediate hosts of human and animal schistosomiasis. Identification of these snails has long been based on morphological and/or genomic criteria, which have their limitations. These limitations include a lack of precision for the morphol...

Background Despite significant progress in malaria control over the past twenty years, malaria remains a leading cause of child morbidity and mortality in Tropical Africa. As most patients do not consult any health facility much uncertainty persists about the true burden of the disease and the range of individual differences in susceptibility to ma...

It is time to review the PZQ MDA. Schistosomiasis MDA will now take into account lower levels i.e. village and not the District or health post area, in order to avoid an overdose or underdose.

According to the latest WHO estimates (2015) of the global burden of foodborne diseases, Listeria monocytogenes is responsible for one of the most serious foodborne infections and commonly results in severe clinical outcomes. The 2013 French MONALISA prospective cohort identified that women born in Africa has a 3-fold increase in the risk of matern...

Respiratory infections, mainly due to viruses, are among the leading causes of worldwide morbidity and mortality. We investigated the prevalence of viruses and bacteria in a cross-sectional survey conducted in Dielmo, a village in rural Senegal with a population of 481 inhabitants. Nasopharyngeal sampling was performed in 50 symptomatic subjects an...

Background Schistosomiasis is a parasitic disease responsible of important morbidity and mortality in sub-Saharan endemic countries. In Senegal, national schistosomiasis control and elimination program has initiated since 2012, annual repeated praziquantel (PZQ) mass drug administration (MDA) in endemic regions in the Senegal River basin (SRB). The...

Background Schistosomiasis remains a public health concern worldwide. It is responsible for more than 240 million cases in 78 countries, 40 million of whom are women of childbearing age. In the Senegal River basin, both Schistosoma haematobium and Schistosoma mansoni are very prevalent in school-age children. However, there is a lack of information...

Termites, predominantly abundant in Africa, represent eusocial insects with a significant ecological role. They have historically served as valuable natural resources in various domains, including traditional medicine, human dietary practices, and livestock nutrition. Fascinatingly, higher termites have cultivated a remarkable symbiotic relationshi...

Female genital schistosomiasis (FGS) caused by Schistosoma haematobium is a neglected chronic parasitic disease. Diagnosis relies mainly on a colposcopy, which reveals non-specific lesions. This study aimed to assess the performance of two sampling methods for the molecular diagnosis of FGS in the uterine cervix. We conducted a descriptive cross-se...

Studying the behaviour and trophic preferences of mosquitoes is an important step in understanding the exposure of vertebrate hosts to vector-borne diseases. In the case of human malaria, transmission increases when mosquitoes feed more on humans than on other animals. Therefore, understanding the spatio-temporal dynamics of vectors and their feedi...

Simple Summary Mosquitoes are capable of transmitting numerous diseases to humans and animals. However, not all mosquitoes are vectors. It is therefore very important to identify mosquitoes in order to distinguish vectors from non-vectors. Our aim was to evaluate the ability of MALDI-TOF MS to identify mosquitoes collected in Senegal and stored for...

Background Thanks to the scale up of malaria control interventions, the malaria burden in Senegal has decreased substantially to the point that the National Malaria Control Programme plans to achieve malaria elimination by 2030. To guide such efforts, measuring and monitoring parasite population evolution and anti-malarial drugs resistance is extre...

West Africa faced the COVID-19 pandemic in early March 2020 and, as of March 31, 2022, had more than 900,000 confirmed cases and more than 12,000 deaths. During this period, SARS-CoV-2 genomes evolved genetically, resulting in the emergence of distinct lineages. This review was conducted to provide the epidemiological profile of COVID-19, the mutat...

The soft ticks, Ornithodoros sonrai, are known as vectors of the tick-borne relapsing fever caused by Borrelia spp. and have also been reported to carry other micro-organisms. The objective of this study was to collect and to identify O. sonrai ticks and to investigate the micro-organisms associated with them. In 2019, an investigation of burrows w...

Blood is a precious biological liquid that is normally sterile. Therefore, bacteria in the bloodstream are shown a priori anomaly. A blood culture is systematically performed to diagnose the cause of the bacteremia. Indeed, a patient received in our service had a thalassemia major and underwent a genoidentical transplant. Then, a blood test was per...

Bartonella species are involved in various human diseases, causing a range of clinical manifestations; animals are considered as the main reservoirs, transmitting diverse species of Bartonella through direct contact and haematophagous insects. Here, we characterize a new species, Bartonella raoultii sp. nov., within the genus Bartonella, using a ta...

We used whole genome sequencing to identify and analyze mutations in SARS-CoV-2 in urban settings during the deadliest wave of the COVID-19 epidemic-from March to April 2021-in Senegal. Nasopharyngeal samples testing positive for SARS-CoV-2 were sequenced on the Illumina NovaSeq 6000 sequencing system using the COVIDSeq protocol. A total of 291 gen...

Understanding the transmission of Schistosoma hæmatobium in the Senegal River Delta requires knowledge of the snails serving as intermediate hosts. Accurate identification of both the snails and the infecting Schistosoma species is therefore essential. Cercarial emission tests and multi-locus (COX1 and ITS) genetic analysis were performed on Bulinu...

• POC laboratories have demonstrated their usefulness in the context of a pandemic (like COVID-19). • The movement of population during major events likely contributed to the spread of SARS-CoV-2 and its variants. • The persistence of the pandemic is due to the high mutation rate of the virus and the constant appearance of variant of concern. • POC...

Background: Urogenital schistosomiasis is a major public health concern in sub-Saharan Africa. In Senegal, the disease is endemic in all regions of the country. Recently, WHO strongly recommended including pre-school children and women of reproductive age during a mass drug administration campaign. It is important to describe the burden of the dis...

Bulinus senegalensis and Bulinus umbilicatus, two sympatric freshwater snails found in temporal ponds in Senegal, were thought to be involved in the transmission of Schistosoma haematobium and/or Schistosoma curassoni. To better understand the role of these Bulinus species in the transmission of human and animal Schistosoma species, B. senegalensis...

Brucella intermedia (formerly Ochrobactrum intermedium), a non-fermentative bacterium, has been isolated from animals and human clinical specimens. It is naturally resistant to polymyxins, including colistin (CO), and may cause opportunistic infections in humans. We isolated six Brucella intermedia strains from Senegalese monkey stool. In order to...

Background Urogenital schistosomiasis is a neglected tropical disease most prevalent in sub-Saharan Africa. In the Senegal river basin, the construction of the Diama dam led to an increase and endemicity of schistosomiasis. Since 2009, praziquantel has frequently been used as preventive chemotherapy in the form of mass administration to Senegalese...

Background: Louse-borne trench fever caused by Bartonella quintana is a neglected public health concern, known to be transmitted from body louse faeces via scratching. No viable B. quintana have ever been isolated from head lice before; therefore, their role as a vector is still poorly understood. Methods: In Senegal, the implementation of a per...

Background: Urogenital schistosomiasis is a major public health concerns in Sub-Saharan Africa. In Senegal, the disease is endemic in all the regions of the country. Recently, WHO strongly recommend including the pre-school children and the women of reproductive age during the mass drug administration campaign. So, it is important to describe the b...

Background Respiratory and gastrointestinal symptoms and febrile illness are the most common complaints among ill pilgrims attending the Grand Magal of Touba (GMT) in Senegal. Methods Patients presenting with respiratory or gastrointestinal symptoms or febrile systemic illnesses were recruited between 2018 and 2021 at a healthcare centre close to...

Ornithodoros sonrai (O. sonrai) ticks are the only known vectors of Borrelia crocidurae, an agent of tick-borne relapsing fever (TBRF) borreliosis. Rodents serve as principal natural reservoirs for Borrelia. Our research objective was to detect TBRF Borrelia and other zoonotic bacterial infections in ticks and in house mice Mus musculus domesticus,...

Two strains, designated as Marseille-P2918 T and Marseille-P3646 T , were isolated from a 14-week-old Senegalese girl using culturomics: Urmitella timonensis strain Marseille-P2918 T (= CSUR P2918, = DSM 103634) and Marasmitruncus massiliensis strain Marseille-P3646 T (= CSUR P3646, = CCUG72353). Both strains were rod-shaped, anaerobic, spore formi...

Using the culturomics approach, the previously unknown strain Marseille-P8953T, was isolated and classified within the Weizmannia genus. Strain Marseille-P8953T was isolated from the faeces of a healthy subject and consisted of Gram-stain positive, spore-forming, motile rod-shaped cells. A 99.2% similarity was observed between the 16S rRNA gene of...

A Gram-positive, aerobic, motile, endospore-forming, rod-shaped bacterium was isolated from a stool sample of a child with marasmus. The 16S rRNA gene showed that strain Marseille-P3601T exhibited 98.68% sequence identity with Ornithinibacillus scapharcae strain TW25. The genomic DNA G+C contents of this strain was 36.9 mol%. The fatty acid profile...

The coronavirus disease 2019 (COVID-19) is a contagious disease caused by a new coronavirus called SARS-CoV-2. The first case was discovered in Wuhan, China, in December 2019, raising concerns about the emergence of a new coronavirus that poses a significant public health risk. The objective of this study, based on data collected and sequenced at t...

Background Respiratory and gastrointestinal symptoms are frequent in pilgrims at the Grand Magal of Touba (GMT). Methods Pilgrims were prospectively investigated in 2017–2021 for demographics, chronic conditions, preventive measures, respiratory and gastrointestinal symptoms, and pathogen carriage using PCR assays. Results 535 pilgrims were inclu...

Background The control of snails intermediate hosts remains an effective strategy to limit schistosomiasis transmission despite the widespread mass de-worming campaign based on praziquantel. Therefore, the study of snail biology could help to improve snails control strategies. This study evaluated the development of Biomphalaria pfeifferi, Bulinus...

Background Rickettsia felis is emergent in tropical areas. Despite its high morbidity, its natural history has not yet been fully determined. We investigated the role of the common household booklouse, Liposcelis bostrychophila, recently found to harbour R. felis. Methods Blood samples from 372 febrile patients from Senegalese villages, as well as...

To achieve the full benefits of vaccination, it is key to understand the underlying causes of low vaccination by researching the barriers to vaccination at a local level. This systematic literature review aims to identify the reasons given by community members for the non-vaccination and under-vaccination of children and adolescents in sub-Saharan...

Understanding the transmission of Schistosoma hæmatobium in the Senegal River Delta requires knowledge of the snails serving as intermediate hosts. Accurate identification of both the snails and the infecting Schistosoma species is therefore essential. Cercarial emission tests and multi-locus (COX1 and ITS) genetic analysis were performed on Bulinu...

Background: In Senegal, the incidence of SARS-CoV-2 evolved with four successive epidemic waves. The first wave started in March 2020 with low virus variability, whilst the second outbreak, which started in December 2020, was dominated by the Alpha variant. The third wave took place in June 2021, and the fourth at the end of November 2021. Our inte...

•Omicron variant continues to progress in Senegal with the appearance of new contaminations.•IRESSEF detected the first positive case of the Omicron variant on Friday, December 3, 2021.•Since this date, the number of Omicron variant infections has increased over the weeks.•Molecular surveillance of the Omicron variant allowed us to identify a stron...

Bed bugs are known to carry several microorganisms. The purpose of this study was to assess the prevalence of bed bug infestation in two rural areas of Senegal and determine the species present in the population. A screening was conducted to detect some arthropod associated pathogenic bacteria in bed bugs and to evaluate the prevalence of endosymbi...

Introduction: Co-administration of the bilié de Calmette et Guérin (BCG) and birth doses of oral polio (OPV zero) and hepatitis B (HepB BD) vaccines is strongly recommended. The objective was to determine the factors associated with this co-administration in the health district of Podor (Senegal). Methods: This cross-sectional study was conducte...

Background Schistosomiasis is a neglected tropical disease most prevalent in sub-Saharan Africa countries. In the Senegal river basin, the construction of the Diama dam led to an increase and endemicity of schistosomiasis. Since 2009, praziquantel has frequently been used as preventive chemotherapy in the form of mass administration to Senegalese s...

Introduction The role of wildlife in the transmission of antimicrobial resistant (AMR) is suspected but scarcely reported in current studies. Therefore, we studied the dynamics and prevalence of antibiotic-resistant Enterobacterales in antibiotic-limited areas of Senegal. Materials and Methods We collected fecal samples from monkeys and apes (N =...

Two bacterial strains were isolated and identified using microbial culturomics and characterised according to the taxono-genomics strategy. The strictly anaerobic strain, Marseille-P3773T, forms smooth and translucent colonies consisting of Gram-stain negative, non-motile and non-spore-forming rod-shaped cells. Strain Marseille-P3787T consists of G...

Background In Senegal, studies focusing specifically on vaccination coverage with the Bacille de Calmette et Guérin (BCG) vaccine, the birth dose of oral polio vaccine (OPV zero dose) and the birth dose of hepatitis B (HepB-BD) vaccine are insufficient. This study aimed to highlight vaccination coverages with birth doses and factors associated with...