État de la résistance du moustique Culex pipiens vis-à-vis du téméphos au centre du Maroc

In Morocco, Culex pipiens plays a role in the high annoyance experienced by most urban cities, suburban and rural areas, especially since it was strongly suspected as the most likely vector in the transmission of West Nile virus epidemics that have hit Morocco in 1996. Chemical insecticides are generally the way in which they use the programs against harmful mosquitoes and disease vectors. However, the repeated and excessive use of these products regularly led to the emergence of the phenomenon of insect resistance. At the center of Morocco, information on the susceptibility or resistance to insecticides in mosquitoes (larvae and adults) vectors of diseases or pests, are almost nonexistent. This article reports the results of studies conducted between 2007 and 2010 with sensitivity tests WHO on larvae local populations of Culex pipiens collected in three lodging in the city of Fez, towards the insecticide mostly used by hygienic services: temephos. Five concentrations of insecticide (0.0025 mg/l, 0.005 mg/l, 0.0125 mg/l, 0.025 mg/l, 0.0625 mg/l) in addition to control, were used to determine the LC50 and LC 90 of Culex pipiens species towards temephos. Sensitivity tests were carried out at the entomology unit and monitoring of insect sensitivity towards insecticides installed at the Regional Diagnostic Laboratory Epidemiological and Environmental Hygiene (LRDEHM), Fez, under the Regional Directorate of Health in Fes Boulemane Region. The LC50 and LC90, concentrations corresponding to 50 and 90% mortality were determined graphically, by the linear relationship between the decimal logarithm of insecticide concentrations (x-axis) and the percentage of mortality transformed into probit values (ordinate) on logarithmic gausso paper. Resistance rates were determined on the basis of the sensitivity of a reference strain (S-Lab). The bioassay results affirmed the presence of resistance in larvae Culex pipiens towards temephos and that this species has also equally developed resistance levels similar and comparable in the three lodging studied, resistance rates recorded varying between 12.17 and 14.34. Facing such a situation, the surveillance of susceptibility of mosquitoes to insecticides used in mosquito control and anti-malarial fight has become imperative. This would undoubtedly allow a good management of the products available and consequently to adopt suitable measures for the best management of this resistance which must be an integral part of any program of vector control.     

Estimation quantitative du risque de contamination d’un don de sang par des agents infectieux

The occurrence of asymptomatic penetration of certain infectious agents in blood presents a risk of transmission of one of these agents during blood transfusion. Although well controlled for some infectious agents (HIV, HTLV, HCV, HBV), this risk is nevertheless neither documented nor quantified for other pathogens that are responsible for serologically unscreened or undetectable infections at the time of blood donation. This risk is generally low in endemic situations, although it increases for particular time periods and locations when clustered cases or outbreaks occur. Prevention measures may then be implemented (interruption of blood collection, quarantined donations, etc.). These measures can have an important impact, particularly by limiting the supply of blood products to health care facilities. It is therefore important for these measures to be adapted to the risk of transmission through blood transfusion. Quantitative risk estimates of blood donation contamination can therefore contribute to guiding those measures. In this context, in early 2005, the French Public Health Institute (InVS) started a project with the aim of obtaining a priori quantitative risk estimates of contamination of a blood donation by infectious agents for various scenarios in terms of incidence and time-space distribution. The objective of this article is to update the last estimates of residual risks of the major transfusion-transmitted viral infections (HIV, HTLV, HCV and HBV) and to present the work realized by the working group « Quantitative estimate of the risk of blood donation contamination by infectious agents».     

Étude séroépidémiologique de la circulation du virus West Nile chez l’Homme en Tunisie

West Nile virus (WNV) is an arbovirus classified into the family of Flaviviridae, genus Flavivirus. It is responsible for neurological diseases that occurred frequently as outbreaks and considered as an emerging infection in different regions of the world. In Tunisia, two outbreaks of meningoencephalitis due to this virus occurred, in 1997 and 2003. The virus circulation is studied only in Sahel, region affected by the two epidemics. The aim of this study is to determine if WNV is present in other regions of the country where, up to now, no data are available. A total of 1,854 sera collected from healthy patients were investigated by ELISA to detect specific IgG, during January to December 2007. Patients included are from three governorates: Kairouan, Bizerte, and Sfax. The governorate of Sfax (center of Tunisia) was affected by the two outbreaks, whereas only two cases were observed previously at Kairouan and no cases at Bizerte. Specific IgG were detected in 12.5% of studied population. This seroprevalence varied largely between the three governorates studied. Globally, three regions with different endemicity were described: high endemicity at Kairouan (27.7%), moderate at Sfax (7.5%), and low at Bizerte (0.7%). At Kairouan, the seroprevalence is significantly higher in individuals aged over 40. Our results suggest that WNV circulates in Tunisia; it has a high risk not only in regions affected by previous outbreaks but throughout the country. An active surveillance should be instituted in the country. It must target individuals, and animals, which can be vectors or reservoirs for the virus.     

Apport de la PCR nichée dans le diagnostic du paludisme d’importation dans le Sud algérien

The nested PCR was used to estimate its inputs in malaria diagnosis and in the performance of the microscope operators involved in the surveillance of malaria in remote areas of South Algeria. For the period 2010 to 2015, 112 patients (93 febrile and 19 asymptomatic) coming from sub-Saharan Africa were tested for malaria in the hospital of Tamanrasset. One part of the blood taken from fingertip was used for blood smears and the second part was absorbed in filter paper for molecular diagnosis. Overall, the infection was detected by nested PCR in 63 samples versus 53 by direct examination. In addition, 11 mixed infections and 6 positive asymptomatic cases not detected by microscopy were diagnosed by PCR. Moreover, two negative samples in nested PCR were tested positive by direct examination. The molecular tool is more sensitive than the direct examination in detecting infra-microscopic parasitaemia and mixed infections...     

Prévention du risque d’œdème aigu pulmonaire associé à la transfusion

Hydrostatic pulmonary edema is a frequent and severe complication of blood transfusion. Recent epidemiological studies open the way for a better prevention of Transfusion-Associated Circulatory Overload. Preventive measures rely solely on the medical and nursing staff. Mitigation strategies include a careful identification of patients and conditions at-risk, a single-unit transfusion policy in patients with chronic anemia, the use of slow infusion rates, the careful monitoring of patient vital signs (particularly systemic arterial blood pressure). Peritransfusion IV diuretics use is likely to be helpful, although optimal prescribing patterns have not been defined.     

Prévalence d’infection des ovins par Toxoplasma gondii en Tunisie

The aim of this study is to estimate the prevalence of Toxoplasma gondii infection in 527 sheep from 4 governorates of Tunisia by Elisa (350 animals) and PCR (177 animals). The seroprevalence in sheep was estimated to be 1.8% (N = 166) in the governorate of Siliana (North Tunisia) and 19% (N = 184) in the governorate of Kasserine (Central Tunisia) with a commercial Elisa kit. T. gondii DNA was extracted from the apex of the heart in 25.5% (N = 106) of sheep from the Sidi-Bouzid governorate (Central Tunisia) and 12.7% (N = 71) from the Ben-Arous governorate (North Tunisia). There was no statistically significant difference between different age categories’ prevalence within each locality. Our results indicate that T. gondii infection is frequent in Tunisian sheep. The implementation of a national control programme against toxoplasmosis should not neglect sheep as a frequently infected intermediate host.     

Investigations entomologiques menées autour de dix cas de fièvre jaune survenus en 2009 dans la région sanitaire du Denguélé, Côte-d’Ivoire

In November 2009, ten suspicious cases of yellow fever, including six deaths, were notified in the region of Denguélé, in the northwest of Côte-d’Ivoire. In order to evaluate the extent of yellow fever virus circulation and the risk for local people, a mission of entomological investigation was carried out by the Ministry of Health and Public Hygiene of Côte-d’Ivoire. Entomological investigations were conducted in the villages of confirmed cases (Banakoro and Tron-Touba) and the centers of consultation and hospitalization of cases during illness. Breteau index and recipient index were quasi nil. Aedes aegypti was absent among the captured mosquitoes. On the other hand, Aedes luteocephalus and Aedes opok were present at Banakoro and Tron-Touba with respective average biting rates of 0.8 and 0.6 bite/man/twilight. This situation of epidemic in the northwest of Côte-d’Ivoire could be explained by the deterioration of Denguélé region’s health system which is a consequence of the war started in the country in 2002 and which has lowered the immunity of the population.     

Prise en charge globale du patient contaminé par le virus Ebola,expérience du Centre de traitement des soignants de Conakry,Guinée

The Healthcare Workers Treatment Center of Conakry, Guinea, was inaugurated in january 2015. It is dedicated to the diagnosis and the treatment of healthcare workers with probable or confirmed Ebola viral disease. It is staffed by the french army medical service. The french military team may reconcile their medical practice and the ethno-cultural imperatives to optimise the patient adherence during his hospitalization.     

Détection de la circulation de virus West Nile chez les Équidés dans le nord-ouest de la Tunisie

Two outbreaks of West Nile Fever (FWN) were observed in the Sahel of Tunisia in 1997 and 2003. Several cases of meningitis and meningoencephalitis have been described in humans during these two outbreaks. However, no animal or clinical findings or seroconversion have been detected despite a high seroprevalence in human beings found around the affected areas. Few data are available regarding the spreading of this virus in other parts of the country. The purpose of this study was to detect a possible WNV spread in horses in some areas of Tunisia considered to be at risk for WNV but which had not been affected by previous outbreaks. A total of 133 equine blood samples were collected in six delegations from three governorates in the north-west of Tunisia. A second blood sampling was taken from animals that were tested negative after the first sampling for IgG to identify possible seroconversion. Detection of IgG was done using competitive ELISA. A significant viral spread was detected in the study area. Out of 133 samples tested for IgG during the first sampling, 36 samples were tested positive (27.1%). Two seroconversions were detected between September and October 2008 out of 84 samples tested. Statistical analysis showed a significant association between the presence of a wetland within 10 km and seroconversion. The presence of cattle seems to be a protective factor.     

Apport d’un laboratoire dans la prise en charge des patients atteints de la maladie à virus Ebola et dans la formation des personnels soignants : expérience du Centre de traitement d’Ebola de Forécariah (Guinée) en 2015

Ebola virus disease (EVD) is associated with a high lethality rate even when the afflicted are provided with good support in an Ebola treatment center (ETC). Basic laboratory tests can help to better understand the pathophysiology of the disease, to guide treatment and to establish simple protocols and procedures tailored to the practice of medicine in the context of such precarious environment for caregivers. Based on a few clinical cases of patients treated in the ETC of Forecariah, Guinea, run by the French Red Cross, this article describes the difficult conditions associated with the provision of medical practice in this challenging environment, aiming to minimize the casualties in the EVD patient and to train the health staff.