[The COVID-19 breaker : PCR to the rescue !] / La déferlante COVID-19 : la PCR à la rescousse ! Chronique d'une gestion de crise au Laboratoire de Microbiologie clinique du CHU de Liège.

Chronicle of a crisis management at the Clinical Microbiology Laboratory of CHU Liège The SARS-CoV-2 outbreak in December 2019 in China and its expansion across the world and Europe have requested the participation of clinical laboratories as major players in the diagnosis of COVID-19, to perform PCR tests mainly on nasopharyngeal swabs. In Belgium, the first confirmed COVID-19 patient was diagnosed in early February, the first of many, especially travelers returning from winter sports. In order to meet the ever-increasing demands for testing, the Clinical Microbiology Laboratory of the CHU of Liege had to adapt to this situation: firstly, by developing manual PCR tests and then automated solutions, permitting to increase the number of analyzes by ensuring a short turnaround time of results. Then, a system for the communication of results on a large scale has been set up, and finally solutions to deal with the lack of sampling devices have been found. This first wave of the pandemic has also highlighted an unprecedented solidarity within the institution. In this article, we recount the chronology of the management of this unprecedented health crisis within the Clinical Microbiology Laboratory of the CHU of Liege.

L'émergence du virus SARS-CoV-2 en décembre 2019 en Chine et son expansion à travers le monde et l'Europe ont sollicité la participation des laboratoires de Biologie clinique en tant qu'acteurs majeurs dans le diagnostic de la COVID-19, via la réalisation de tests PCR principalement sur des prélèvements nasopharyngés. En Belgique, le premier patient confirmé COVID-19 a été diagnostiqué début février, avant d'être suivi par de nombreux cas d'infections, initialement chez des vacanciers revenant des sports d'hiver. Afin de répondre à l'augmentation du nombre de tests, le laboratoire de Microbiologie clinique du CHU de Liège a dû s'adapter en développant des tests PCR, d'abord manuels puis automatisés. Ceux-ci ont permis d'augmenter le nombre d'analyses, tout en garantissant un temps de rendu des résultats court, en mettant en place un système de communication des résultats à grande échelle et en trouvant des solutions pour faire face à la pénurie des dispositifs de prélèvement. Cette première vague de la pandémie a aussi révélé une solidarité sans précédent au sein de l'institution. Dans cet article, nous retraçons la chronologie de la gestion de cette crise sanitaire inédite au sein du laboratoire de Microbiologie clinique du CHU de Liège.

Study of NAT2 genetic polymorphism in West African subjects: example of an healthy non-smoker Senegalese population.

The NAT2 genetic polymorphism determines the individual acetylator status and, consequently, the capacity to metabolize, or not, drugs and xenobiotics which are substrates of NAT2. As the nature and frequency of the NAT2 polymorphisms vary remarkably between populations of different ethnic origins, genotyping strategies used to predict the acetylation phenotype need to be adapted for each particular population regarding their genetic backgrounds at this locus. As few data on the genetic polymorphism of NAT2 are available in the Senegalese population, we performed an extensive identification of NAT2 variants in 105 healthy non-smoker Senegalese subjects by direct PCR sequencing of the coding region. Eleven previously described SNPs were identified in this Senegalese population. Upon allele analysis, the four most frequent alleles were of the NAT2*5- (35.7 %), NAT2*6- (21.0 %), NAT2*12- (16.7 %) and NAT2*14- (10.0 %) type, the remaining alleles, including the wild-type NAT2*4, having each a frequency lower than 10 %. According to the observed genotypes, 51 and 50 subjects were predicted to be of the rapid (48.6 %) and slow (47.6 %) acetylator phenotype, respectively, while four individuals (3.8 %) were considered of unknown phenotype as they carry at least one allele with a yet unknown functional effect. These baseline data would be of particular interest to set up an efficient genotyping strategy to predict the acetylation status of Senegalese patients with tuberculosis and, thus, to optimize their isoniazid treatment.

[Acceptability of implementation of mutual health in a Senegalese rural area]. / Acceptabilité de la mise en place de mutuelle de santé en milieu rural sénégalais.

UNLABELLED: Funding for healthcare poses a major problem in developing countries. The purpose of this study was to assess public perceptions toward the implementation of mutual healthcare coverage in rural Senegal. METHODS: A descriptive transversal study was conducted from 24/09/07 to 05/10/07 in a randomly selected sample of 208 heads of households living in the rural communities of Ngogom and Réfane. Data were collected by means of individual interviews and focus group discussions. Topics included population health, community solidarity, health insurance and implementation of mutual healthcare insurance. RESULTS: The sample population was 94% male, 91% married, 36% uneducated and 11% unemployed. Household income was irregular in 36% and 84% had no savings. In case of medical emergency, 43% relied on family for assistance, 36% had no recourse and 21% would have to contract, a loan. Nearly half the sample population, i.e., 46%, were familiar with the principle of mutual healthcare insurance and 98% wanted to join. The main reasons for wanting to join were to reduce medical costs (57%), improve access to care (25%) and build community solidarity (11%). In focus groups, people expressed the need for micro health insurance. Findings also showed good community dynamics and a tradition of pooling resources to implement collective activities. CONCLUSION: The public perception of mutual healthcare insurance is favorable. However, due to economic difficulties, support from political and health authorities will be needed.

[Epidemiology of human schistosomiasis in Mauritania. The right bank of the Senegal River as model]. / Épidémiologie des bilharzioses humaines en Mauritanie. L'exemple de la rive droite du fleuve Sénégal.

A study was performed to determine the transmission and prevalence of human schistosomiasis in the Mauritanian side of the Senegal River basin. Parasitological investigations by Kato-Katz and urine filtration conducted on 1,259 school children indicated a mean prevalence of S. haematobium--29.0%, 25.9% and 34.3%, respectively, in the children of the lower, middle and high valley. Only the school children of the lower delta valley were infected by S. mansoni with a mean prevalence rate of 21.5%. The malacological investigations carried out in the water points of each visited village highlighted the presence of B. pfeifferi, B. senegalensis, B. globosus, B. umbilicatus, B. truncatus and B. forskalii. The last three species are announced for the first time in the Mauritanian side of the Senegal River. The laboratory snail infection experiments indicate that B. senegalensis and B. globosus are the most important intermediate hosts for S. haematobium in the Mauritanian side of the Senegal River basin. However, an incompatibility between the oasis strains of S. haematobium and the snails of the lower valley was noted. In the middle valley and high valley, the infection of the school children takes place during the rainy season, because of the creation of the temporary water points, in the lower valley; the transmission seems to be continuous.

Prevention of isoniazid toxicity by NAT2 genotyping in Senegalese tuberculosis patients.

Isoniazid (INH), recommended by WHO (World Health Organization) in the treatment of tuberculosis (TB), is metabolized primarily by the genetically polymorphic N-acetyltransferase 2 (NAT2) enzyme. The human population is divided into three different phenotypic groups according to acetylation rate: slow, intermediate, and fast acetylators. The objective of this study was to explore the relationship between NAT2 genotypes and the serum concentrations of INH. Blood samples from 96 patients with TB were taken for the analysis. NAT2 polymorphisms on coding region were examined by polymerase chain reaction (PCR) direct sequencing; the acetylation status was obtained by measuring isoniazid (INH) and its metabolite, acetylisoniazid (AcINH) in plasma was obtained by using the liquid chromatography coupled to mass spectrometry. TB patients were distributed into two groups of fast and slow acetylators according to the acetylation index calculated based on the plasma concentration of INH in the 3rd hour (T3) after an oral dose. Our PCR analysis identified several alleles, where NAT2*4, NAT2*5A, NAT2*6A, and NAT2*13A were the most important. The concentrations of INH varied between 1.10 mg/L and 13.10 mg/L at the 3rd hour and between 0.1 and 9.5 mg/L at the 6th hour. The use of the acetylating index I3 allowed the classification of tested patients into two phenotypic groups: slow acetylators (44.3% of TB patients), and rapid acetylators (55.7%). Patient's acetylation profile provides valuable information on their therapeutic, pharmacological, and toxicological responses.

Constructive techniques for zeros of monotone mappings in certain Banach spaces.

Let E be a 2-uniformly convex real Banach space with uniformly Gâteaux differentiable norm, and [Formula: see text] its dual space. Let [Formula: see text] be a bounded strongly monotone mapping such that [Formula: see text] For given [Formula: see text] let [Formula: see text] be generated by the algorithm: [Formula: see text]where J is the normalized duality mapping from E into [Formula: see text] and [Formula: see text] is a real sequence in (0, 1) satisfying suitable conditions. Then it is proved that [Formula: see text] converges strongly to the unique point [Formula: see text] Finally, our theorems are applied to the convex minimization problem.

Beam collimation and bolusing material optimizations for 10boron neutron capture enhancement of fast neutron (BNCEFN): definition of the optimum irradiation technique.

PURPOSE: In boron-10 neutron capture enhancement of fast neutron irradiation (BNCEFN), the dose enhancement is correlated to the 10B concentration and thermal neutron flux. A new irradiation technique is presented to optimize the thermal neutron flux. METHODS AND MATERIALS: The coupled FLUKA and MCNP-4A Monte Carlo codes were used to simulate the neutron production and transport for the Nice and Orleans facilities. RESULTS: The new irradiation technique consists of a 20-cm lead blocks additional collimator, placed close to the patient's head, which is embedded in a pure graphite cube. A 24-fold thermal neutron flux increase is calculated between a 5 x 5 cm2 primary collimated field, with the patient's head in the air, and the same field size irradiated with the optimum irradiation technique. This increase is more important for the p(60)+Be Nice beam than for the p(34)+Be Orleans one. The thermal neutron flux is 2.1 x 10(10) n(th)/Gy for each facility. Assuming a 100 microg/g 10B concentration, a physical dose enhancement of 22% is calculated. Moreover, the thermal neutron flux becomes independent of the field size and the phantom head size. CONCLUSION: This technique allows conformal irradiation of the tumor bed, while the thermal neutron flux is enhanced, and spreads far around the tumor.

Ten years of research activities on tropical parasitology of dromedaries, cattle, and small ruminants in Mauritania.

In the past, the essential part of the activity of the parasitology laboratory of the Centre National d'Elevage et de Recherches Vétérinaires (CNERV) was represented by diagnostic work that enabled the construction of an inventory of local parasitic fauna and a good collection of specimens. However, the small and irregular number of samples each year, led us to switch our activities in 1990 toward work that could better justify the existence of CNERV. We started work on applied research topics, such as tick-borne diseases, helminthology (nemathelminths and plathelminths), and trypanosomosis. These results were valorized through scientific publication and communication at international meetings. The most valuable information was conveyed to herders.

Combined use of FLUKA and MCNP-4A for the Monte Carlo simulation of the dosimetry of 10B neutron capture enhancement of fast neutron irradiations.

Boron neutron capture enhancement (BNCE) of the fast neutron irradiations use thermal neutrons produced in depth of the tissues to generate neutron capture reactions on 10B within tumor cells. The dose enhancement is correlated to the 10B concentration and to thermal neutron flux measured in the depth of the tissues, and in this paper we demonstrate the feasibility of Monte Carlo simulation to study the dosimetry of BNCE. The charged particle FLUKA code has been used to calculate the primary neutron yield from the beryllium target, while MCNP-4A has been used for the transport of these neutrons in the geometry of the Biomedical Cyclotron of Nice. The fast neutron spectrum and dose deposition, the thermal flux and thermal neutron spectrum in depth of a Plexiglas phantom has been calculated. The thermal neutron flux has been compared with experimental results determined with calibrated thermoluminescent dosimeters (TLD-600 and TLD-700, respectively, doped with 6Li or 7Li). The theoretical results were in good agreement with the experimental results: the thermal neutron flux was calculated at 10.3 X 10(6) n/cm2 s1 and measured at 9.42 X 10(6) n/cm2 s1 at 4 cm depth of the phantom and with a 10 cm X 10 cm irradiation field. For fast neutron dose deposition the calculated and experimental curves have the same slope but different shape: only the experimental curve shows a maximum at 2.27 cm depth corresponding to the build-up. The difference is due to the Monte Carlo simulation which does not follow the secondary particles. Finally, a dose enhancement of, respectively, 4.6% and 10.4% are found for 10 cm X 10 cm or 20 cm X 20 cm fields, provided that 100 micrograms/g of 10B is loaded in the tissues. It is anticipated that this calculation method may be used to improve BNCE of fast neutron irradiations through collimation modifications.

Some factors affecting the prevalence of Trypanosoma evansi in camels in Mauritania.

A study was conducted on the epidemiology of camel trypanosomosis in Mauritania using 2073 camels of various ages in five regions (Trarza, Gorgol, Adrar, Hodh E1 Chargui, Nouakchott). The prevalence was determined through blood smear and serological tests: card agglutination test for trypanosomiasis (CATT) and immuno fluorescence antibody test (IFAT). The prevalence of the disease was 1.3% using blood smear examinations, 16.2% with CATT and 25.2% with IFAT. The following variations were observed: (1) Camels in Trarza had the highest prevalence; (2) Intraregion was a significant factor; (3) Animals that migrated to the south were more commonly infected than those in the north; and (4) Animals in the 5- to 10-yr age group had the highest prevalence. The study indicated that camel trypanosomosis was widespread in Mauritania, especially in the wooded areas near waterways in the south.

Cooperia pectinata and C. punctata, parasites of the abomasum of cattle in northern Cameroon (Central Africa).

Cooperia pectinata Ransom, 1907 and C. punctata von Linstow, 1907 are common trichostrongyles of zebu cattle in Africa. Their intestinal localization within the digestive tract is considered by many authors to be exclusive. Nevertheless, some limited surveys in Malagasy, Mauritania, The Gambia and Cameroon reported the presence of both Cooperia species in the abomasum. The present survey was carried out in a slaughterhouse of northern Cameroon on 17 zebu cattle and confirms the infection of the small intestine and the abomasum by the two species within the total number of cattle examined. Abomasal infections especially with Cooperia punctata were heavier than those in the intestine. Due to the movements of herdbreeders in Central Africa, and to the preliminary results obtained in Mauritania, The Gambia, Burkina Faso and Malagasy, abomasal localization of C. pectinata and C. punctata may be encountered in very large areas of Africa, and that cooperiosis may contribute together with Haemonchus species to the digestive disorders involving the abomasum.

[Frequency, risk factors and prognostic value of anemia associated with HIV/AIDS in the adult in Mali]. / Fréquence, facteurs de risque et valeur pronostique de l'anémie associée au VIH/SIDA chez l'adulte au Mali.

Anaemia is a common complication of the HIV infection. To understand the mechanism of HIV associated anaemia and to suggest a consequent therapeutic approach in adults in Mali, we undertook a prospective case/control study in two services of reference with essentially adults recruitment in Bamako. We studied the frequency, the risk factors and the prognosis value of this complication in 133 patients with HIV infection matched to 133 others non HIV infected. The average age of our patients was 36.08 +/- 8.80 years (age range: 19 to 66 years). The frequency of anaemia was significantly higher in patients with HIV infection compared to the controls (78.9% vs. 51.9%; OR = 2.46; 95% CI [1.56-3.92]). Anaemia was more frequent in women than in men (p = 0.00003). A significant association between anaemia and thrombopenia or lymphopenia was observed only in patients with HIV infection. The severity of anemia was positively associated with the HIV2 infection and the progression of the HIV disease. Mortality was more frequently associated to the anaemia (p < 10(-5)) in patients infected by HIV. These findings suggest that bone marrow depression leading to a decreased red blood cells production is the main mechanism of HIV associated anaemia in adult in Mali. Therefore, without evidence of a best cost-effectiveness ratio of a human recombinant erythropoietin treatment in the context of countries with a low income, the therapy of this haematological complication must be an emergency focusing on red blood cells transfusions.

[Scapulo-thoracic mycetoma. A rare localization, a particular form]. / Mycétome scapulo-thoracique. Une localisation rare, une forme particulière.

INTRODUCTION: An uncommon form and a rare localization of mycetoma is reported. The aim of this report was to distinguish this inhabitual form of mycetoma from some tropical diseases like onchocerca and other fungal diseases. CASE REPORT: A 55 year old man was admitted 10 years after a septic worm-hole for a scapulo-thoracic tumor. This encapsulated mass was a bending and rounded polyfistular one attached to the dorsal aspect of left shoulder. The fistula discharge a serosanguineous or purulent exudate. The characteristic red granule was not visible. The tumor was removed and histological examination was performed. A typical granuloma of red granule of streptomyces pelletieri was found. A good result was obtained with associated cotrimoxazole treatment. DISCUSSION: Scapulo-thoracic form included: scapular, axillary and chest form of mycetoma. All these localizations are rare. One of them can be complicated by osteitis or pleuro-pulmonary localization. Streptomyces pellitieri is the actinomycetic causal agent. This encapsulated form is uncommon. CONCLUSION: Scapulo-thoracic mycetoma is rare. Encapsulated and pedicular form is uncommon. Around Sahel areas, differential diagnosis must be evoked such as parasitic and mycobacterial infections.

[The fluorosis problem in Senegal: data evaluation and presentation of a new method for defluoridating the water supply]. / Sur le problème de la fluorose au Sénégal: bilan des connaissances et présentation d'une nouvelle méthode de défluoruration des eaux de boisson.

Fluoride intoxication is a serious public health problem in Senegal. The concentration of fluoride ions in underground water in Senegal is higher than the acceptable standard (0.7 mg/l at 25 degrees C) varying between 5 and 15 mg/l according to the season. The hydrological pattern of fluoride ions in Senegalese water is presented. The high levels of fluoride ions are due to the presence of phosphate ores. The health problems associated with the ingestion of toxic doses (about 4 mg/l) are discussed. Epidemiological investigation shows that the intoxication in Senegal is serious. In addition to fluoride in drinking water, high levels are also found in food, particularly tea and vegetables. Nanofiltration is a low cost membrane-based process which can be used to eliminate fluoride from drinking waters. Also known as low pressure reverse osmosis, this process is selective for small molecules and ions. It can thus sterilize and partially demineralize water. Furthermore, it can require only small amounts of energy, such that it can be run from photoelectric cells.

Human T-cell leukaemia/lymphoma virus type 1-associated infective dermatitis in Africa: a report of five cases from Senegal.

BACKGROUND: Infective dermatitis (ID) is a rare dermatological condition of childhood that has been linked to human T-cell leukaemia/lymphoma virus type 1 (HTLV-1). Most cases have been reported in the Caribbean. Although several million people are estimated to be infected by HTLV-1 in sub-Saharan Africa, no case of ID has been reported in this area. OBJECTIVES: To identify and to describe cases of HTLV-1-associated ID in Senegal, West Africa. METHODS: Over a 3-year period, a serological test for HTLV-1 was performed at a dermatological centre in Dakar, Senegal, in children who presented with a picture suggestive of ID. Complementary haematological, immunological and virological investigations were performed in infected children and in their mothers. RESULTS: Five patients with typical HTLV-1-associated ID were identified, of ages 17, 5, 4, 3 and 3 years; two patients belonged to the same family. They all presented with repeated flares of superinfected dermatitis involving typical sites of ID (mainly the scalp, external ears, nares and eyelids), associated with nasal discharge, and less commonly with a nonspecific papular rash on the face or trunk. Although oral antibiotic therapy always gave effective control of the symptoms, recurrences were constant. A persisting dry dermatitis of the retroauricular folds was common between flares. Infection in the oldest patient was associated with a chronic adult T-cell leukaemia/lymphoma. The mothers of three patients, and the grandmother of another, were all infected by HTLV-1 strains belonging to the Cosmopolitan molecular subtype, with a perfect nucleotide identity of long-terminal repeat and env gp21 genomic regions within each family. CONCLUSIONS: We present the clinical and virological features of the first reported African cases of HTLV-1-associated ID. When compared with data from the Caribbean, infectious features seemed particularly prominent. ID appears to be overlooked in sub-Saharan Africa, where it might be easily confused with common pyoderma. Breast feeding appears to be the origin of HTLV-1 contamination of the children.