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E Nicand

Publications and source records attributed to E Nicand.

At least 19 recordsLinked to original sources
PubMed2006

Validation of single real-time TaqMan PCR assay for the detection and quantitation of four major genotypes of hepatitis E virus in clinical specimens.

Since the characterization of the genome of the hepatitis E virus (HEV) in 1990, a large genetic diversity has been described. A single real-time reverse transcription (RT)-PCR assay with TaqMan technology has been validated which uses only one set of primers and probe within the ORF2 HEV region (nt 5207-5292) for the detection and quantification of the four major genotypes of HEV. This assay proved to be as efficient as the conventional RT-PCR methodology for the detection of HEV in clinical samples testing positive previously. The real-time RT-PCR and conventional RT-PCR were performed comparatively on 60 pairs of sera and stools collected during a recent outbreak of hepatitis E in Darfur. The real-time RT-PCR assay was 10- to 100-fold sensitive than for conventional RT-PCR assays used in this study with a range quantitation from 1.8 x 10(1) to 7.2 x 10(3) RNA copies/microl in clinical samples (serum and stools).

Genome, Viral↗
PubMed2006

[Impact and forecasting of hepatitis A immunization in French armed forces, 1990-2004].

BACKGROUND: Hepatitis A is a public health problem specially for migrants or travellers from industrialized countries with a low hepatitis A endemic level. French armed forces adopted an immunization strategy which first targeted overseas forces and subsequently was extended to all armed forces. In this work we studied the impact of this policy. METHODS: Epidemiological surveillance data from 1990 to 2004 was analyzed by Poisson regression and exponential models of decrease used to forecast future rates. RESULTS: From the 826 cases of hepatitis A reported during the study period, 266 (32.2%) occurred in overseas forces and 560 (67.8%) in forces stationed in France. Three periods could be identified in the decline of annual incidence: before 1994, with an average rate of 23.2 per 100,000; from 1994 to 1998: 10.2; and after 1998: 1.2 for all French armed forces. For overseas armed forces, the average rate was 117 per 100,000 before 1994 and 17.1 from 1994 to 1998 (p<0.001). For armed forces stationed in France, the average rate was 12.2 per 100,000 before 1998 and 0.9 after (p<0.001). For overseas armed forces, models clearly described the declining incidence subsequent to targeted immunization in 1995 and for armed forces stationed in France, the decline with generalized immunization starting in 1998. DISCUSSION: The impact of immunization against hepatitis A virus was significant both in an overseas population and in a population staying in France where the risk level can be considered low due to the low endemic rate in France. These results suggest that immunization should be proposed not only for travellers but also for the general population based on real knowledge of the situation and cost-effectiveness analyses.

Forecasting↗
PubMed2006

[Contact tracing in a case of tuberculosis in a health care worker].

INTRODUCTION: Tuberculosis is a public health problem, of which the nosocomial transmission from a health care worker to patients has not been well documented. OBSERVATIONS: A Senegalese surgeon aged 32 was admitted to hospital on account of deterioration in his general health. He was found to have sputum positive tuberculosis and received standard treatment. We report the strategy employed for tracing the contacts of this health care worker. Of a total of 185 members of staff (permanent and temporary) and 91 patients who had been in contact with the index case, 180 (97.3%) and 71 (78%) respectively were screened. Of the 251 subjects screened, 5 staff (2.8%) and 11 patients (15.4%) showed evidence of latent tuberculous infection and 6 were treated. In total 97.3% of staff exposed were screened at the beginning of the study and 63% were reviewed at 3 months as opposed to 78% and 53% for the patients. CONCLUSION: This study shows poor compliance with the visit 3 months after exposure and the need to standardise the procedures in order to improve the screening and follow up of contacts.

Adult↗
PubMed2006

Identification of genotype 1 hepatitis E virus in samples from swine in Cambodia.

Hepatitis E virus (HEV) is a major enterically transmitted pathogen in many developing countries, where it causes outbreaks and sporadic cases of acute hepatitis. A study conducted with pigs from several livestock farms in Cambodia identified one swine genotype 1 HEV isolate as being associated with prevalent swine genotype 3 HEV.

Animals↗
PubMed2004

Surveillance network for herpes simplex virus resistance to antiviral drugs: 3-year follow-up.

Herpes simplex virus (HSV) infections are very common in the general population and among immunocompromised patients. Acyclovir (ACV) is an effective treatment which is widely used. We deemed it essential to conduct a wide and coordinated survey of the emergence of ACV-resistant HSV strains. We have formed a network of 15 virology laboratories which have isolated and identified, between May 1999 and April 2002, HSV type 1 (HSV-1) and HSV-2 strains among hospitalized subjects. The sensitivity of each isolate to ACV was evaluated by a colorimetric test (C. Danve, F. Morfin, D. Thouvenot, and M. Aymard, J. Virol. Methods 105:207-217, 2002). During this study, 3900 isolated strains among 3357 patients were collected; 55% of the patients were immunocompetent. Only six immunocompetent patients excreted ACV-resistant HSV strains (0.32%), including one female patient not treated with ACV who was infected primary by an ACV-resistant strain. Among the 54 immunocompromised patients from whom ACV-resistant HSV strains were isolated (3.5%), the bone marrow transplantation patients showed the highest prevalence of resistance (10.9%), whereas among patients infected by human immunodeficiency virus, the prevalence was 4.2%. In 38% of the cases, the patients who excreted the ACV-resistant strains were treated with foscarnet (PFA), and 61% of them developed resistance to PFA. The collection of a large number of isolates enabled an evaluation of the prevalence of resistance of HSV strains to antiviral drugs to be made. This prevalence has remained stable over the last 10 years, as much among immunocompetent patients as among immunocompromised patients.

Acyclovir↗
PubMed2004

Clinical evaluation of the gen-probe amplified mycobacterium tuberculosis direct test for rapid diagnosis of tuberculosis lymphadenitis.

This prospective study evaluated the performance of the Amplified Mycobacterium Tuberculosis Direct Test (MTD) for the diagnosis of lymph node tuberculosis in Djibouti, Republic of Djibouti. Of 197 specimens sampled from 153 patients, 123 were from 95 tuberculous patients. The sensitivity and specificity of MTD were 93 and 100%, respectively. The sensitivity of culture was 89%.

Culture Media↗
PubMed2003

[Outbreak of tropical phagedenic ulcers after the rainy season in Dijibouti].

The incidence of cutaneous ulcers was observed after the rainy season in Djibouti in 1997. Based on the study of epidemiologic, clinical, biological, and therapeutic features these lesion were classified as phagedenic ulcers. While direct examination showed numerous fusiform bacilli, cultures performed in one patient, led to isolation of numerous colonies of Prevotella loescheii. Though less common, two other anaerobic bacterial species were detected, i.e., Peptostreptococcus anaerobius and Peptostreptococcus sp.

Adolescent↗
PubMed2002

Quantification and duration of viraemia during hepatitis A infection as determined by real-time RT-PCR.

Human transmission studies and molecular techniques have provided evidence that transient viraemia occurs during infection with hepatitis A virus (HAV). However, the duration of its presence and levels during the phases of clinical disease and convalescence has not yet been well studied in human patients. Real-time RT-PCR techniques are increasingly used to quantify RNA viruses for diagnosis and/or research purposes. We have optimized a one-step RT-PCR that contains a dual-labelled fluorogenic probe to quantify the 5' noncoding region (5' NCR) of HAV. This method has a dynamic range (5-5 x 10(6) copies). The coefficient of regression of the standard curve was, on average 0.978. Intra-assay CVs% varied from 6.1% to 0.98%, and interassay CVs% from 6.46% to 2.1%. In the currently reported study 41 HAV IgM positive serum samples and 200 serum samples from healthy blood donors were tested by the quantitative RT-PCR method. The mean values on the first day of diagnosis found was 6.38 x 10(5) copies/mL. In a longitudinal study, viraemia persisted for an average of 60 days after clinical onset. These results show that viraemia in HAV infection lasts for many weeks.

Adolescent↗
PubMed2002

[Sero-epidemiological study of the hepatitis epidemic in Mitrovica in the aftermath of the war in Kosovo (1999)].

In July 1999, after the return of the Kosovar refugees to their country, an outbreak of acute hepatitis A (HAV) and E (HEV) occurred. Epidemic hepatitis and diarrhoea are closely monitored communicable diseases which had been singled out as priorities by the health authorities of the former Republic of Yougoslavia. Several field surveys were undertaken: description of reported cases, serological study of clinical patients, study of anti-HAV seroprevalence in a school and a case control study to assess risk factors. The analysis of the reports indicates an epidemic peak at the end of September, 2 or 3 weeks after the start of the new school year, with an increase of cases relative to the age of the children in school. In a serologic study of 104 samples, we found an anti-HAV IgM positivity in 88% of the cases. Children were more likely to be positive when compared to teenagers and adults; likewise, consumers of well-water as versus those drinking network water (p = 0.03). The study of seroprevalence showed that transmission had taken place within the school. The case control study, in spite of its imperfections, indicated that consumption of water melon, the only fruit cultivated locally, is a factor which facilitates the HAV transmission. Circulation of the hepatitis E virus was confirmed for 4 sick persons (including 2 co-infected HAV-HEV) and in 4 persons without clinical symptoms. These results show the permanent risk of faeco-oral infections in this area and the need to develop a relevant prevention policy.

Adolescent↗
PubMed2002

[Status of resistance of HIV-1 strains in Africa: what is the role of viral surveillance networks?].

The human immunodeficiency virus (HIV-1) epidemic has spread dramatically in sub-Saharan African countries. Implementation of active antiretroviral (ARV) therapy programs is urgently needed. However this emergency situation must not extenuate the importance of preliminary studies on ARV resistance of African HIV-1 isolates. Findings show that genetic mutations underlying the resistance of African strains are generally identical to those observed in HIV-1 subtype B in industrialized countries. However the incidence of some mutations associated with mild resistance to protease inhibitors (PI) appears higher in African isolates. The potential impact of these mutations for development of frank resistance to PI is still unclear. The incidence of high-grade resistance markers in untreated subjects is low. While these results do not compromise use of ARV therapy in Africa, they underline the need to set up local networks for patient follow-up and to carry out epidemiological surveillance of HIV-1 resistance. Success of ARV therapies in Africa will also depend on economic and social programs.

Africa↗
PubMed2001

Allogenic bone marrow transplantation with a donor presenting with an acute hepatitis A.

We report the unique occurrence of an allogenic bone marrow transplantation performed as the donor was suffering from an acute hepatitis A. The bone marrow was contaminated at the time of collection, as demonstrated by hepatitis A virus (HAV) RNA detected by RT-PCR. Hepatitis A virus infection in such a situation could have resulted in a severe liver disease in the recipient. However, although we could demonstrate that the recipient had been infected, he did not develop a symptomatic hepatitis A but only minor disturbances of liver function tests between days 35 and 55. Both the postponement of the transplantation and the use of intravenous polyvalent immunoglobulins have probably played a key role in decreasing the viral load and allowing a rapid clearance of the virus. A possible role of the grafted immune system might also be envisaged, as suggested by the de novo synthesis of IgM in the recipient.

Acute Disease↗
PubMed2000

Identification of a novel hepatitis E virus in Nigeria.

Sporadic cases of acute hepatitis E among ten native Nigerian adults were reported in Port-Harcourt (Nigeria). Hepatitis E virus (HEV) was detected in serum and/or faecal samples of seven patients by RT-PCR of the open reading frame (ORF)-1 polymerase region and the 3'-end of ORF2. Restriction analysis widely used to distinguish genotypes I and III showed that all Nigerian strains have a pattern similar to the Mexican strain (NotI, nt 286; SmaI, nt 397; no KpnI restriction site) but displayed a BsmI restriction site at nt 213 as do most African HEV strains sequenced so far. Sequence analysis performed from internal ORF1 and ORF2 PCR products displayed strong homogeneity between the HEV isolates, determining a regional cluster. Phylogenetic analysis of nucleotide sequences revealed that these strains were more related to the Mexican prototype genotype III (87% homology in ORF1, 80% homology in ORF2) than to either the African strain genotype I (74% homology in ORF1, 77% homology in ORF2) or the USA strain genotype II (75% homology in ORF1, 77% homology in ORF2). Genetic divergence up to 15% in ORF2 with the Mexican genotype clearly defined a new subgenotype within genotype III. At the amino acid level, Nigerian strains showed more homology with genotype III (96%) than with genotype I (92%). This study clearly determined the co-existence of genotypes I and III in Africa. These Nigerian HEV strains belonging to genotype III, but sharing some properties with genotype I, could be one of the missing links between African and Latin American HEV and could help us to determine the phylogenetic evolution of HEV from the ancestral virus.

Adult↗
PubMed1999

[Fall in the seroprevalence of hepatitis A in French youth].

OBJECTIVE: An anti-hepatitis A virus seroprevalence survey was performed in 1997 in 1052 French army recruits (mean age: 21.2 years). To describe epidemiological trends, the current pattern was compared to previous results obtained by similar methods in 1985, 1990 and 1993. RESULTS: In 1997, overall anti-hepatitis A virus seroprevalence was 11.5%. The greatest risk factor of hepatitis A infection was related to travel in intermediate or highly endemic areas for hepatitis A virus: 46% of overseas residents (odds ratio = 10.3), 28% of recruits who had travelled in developing countries (odds ratio = 3.7) and 7.65% of French living in industrialised countries are anti-hepatitis A virus antibody positive. Moreover, seroprevalence was higher in subjects with a history of icteria (adjusted odds ratio = 3.5) and families with at least 3 children (adjusted odds ratio = 3). No association was found with drinking water, socioeconomic status such as baccalaureat degree, or parents profession. The seroepidemiological shift of hepatitis A, as assessed in three previous studies, shows a marked decrease of 20% in 12 years from 30.4% in 1985, to 21.3% in 1990, to 16.3% in 1993, and to 11.5% in 1997. The decrease in the prevalence of anti-hepatitis A virus was more marked in young adults who had never travelled in endemic countries (decrease of 20%) than those who had visited or lived in developing countries (decrease of 10%). CONCLUSION: Although France is not highly endemic for hepatitis A thanks to improved hygiene and housing conditions over the past 20 years, a pattern of intermediate endemicity was seen in French overseas areas in which the risk of outbreaks of hepatitis A was higher. The decrease in anti-hepatitis A virus seroprevalence in French youth can be used to draft a public health policy for hepatitis A control.

Adolescent↗
PubMed1999

[Hepatitis C in tropical areas].

The tropical features of hepatitis C have not yet been fully elucidated due to the scarcity of data. However it has been estimated that two-thirds of the infected population lives in tropics. The most heavily affected regions are Africa, China, and southeast Asia with prevalence rates of 5.3, 3.0, and 2.4 p. 100 respectively. In several countries mostly in Africa, prevalence rates range from 5 to 10 p. 100 or higher. Age is a major risk factor for infection. The classic transmission modes, i.e., blood transfusion and intravenous drug use, do not account for these high prevalence rates. Another mechanism could be parenteral injection under unsafe conditions. The most widespread genotypes in tropical areas are genotypes 1, 2, and 3. Other genotypes can be encountered locally including genotype 4 in black Africa and Egypt, genotype 6 in southeast Asia, and genotypes 1 and 3 in India. The association of hepatitis C with chronic liver disease has been the focus of several studies, mainly in Africa. The seroprevalence of virus C ranges from 2 to 55 p. 100 in cases of chronic hepatitis or cirrhosis and from 0 to 47 p. 100 in cases of hepatocellular cancer. Hepatitis C could be the underlying cause of 33 to 50 p. 100 of chronic liver diseases not linked to virus B. It is observed more often in patients with chronic hepatitis or cirrhosis than cancer in which virus B is dominant. Infection by both virus is rare without liver disease but is more frequent in patients with cancer than chronic non-tumoral liver disease.

Africa↗
PubMed1997

[Non-vaccinal prophylaxis for orally transmitted diseases].

Many diseases are transmitted to man by consumption of contaminated food and drinking water. Orally transmitted diseases are among the main risks for travelers in developing and tropical countries. A variety of clinical manifestations can be observed but the diarrhea is the most common. In many cases bacterial gastroenteritis, typho-paratyphoidal fever, brucellosis, viral hepatitis, and various parasitic diseases can develop after various periods of incubation following consumption of contaminated food or drink with no initial reaction. Vaccination can afford protection against only few diseases. Prevention by applying good hygiene and common sense is the best method. By following the standard list of food precautions, travelers can minimize the main risks. Drug prophylaxis is recommended only under special circumstances. Travel medicine providers must have up-to-date information and possess the persuasive powers necessary to convince travelers to apply recommendations despite the major inconveniences.

Communicable Disease Control↗