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Y Buisson

Publications and source records attributed to Y Buisson.

At least 55 records · Page 3Linked to original sources
PubMed1996

Study of Pseudomonas aeruginosa serotype O12 isolates with a common antibiotic susceptibility pattern.

A multicentre European study of Pseudomonas aeruginosa serotype O12 isolates with a common antibiotic resistance pattern was conducted. Resistance to beta-lactams and aminoglycosides was observed in 24 of the 25 isolates, as often reported in Europe, and all 25 isolates were significantly more susceptible to fosfomycin than 189 isolates of other serotypes (72% vs. 13.2%). The mutational frequency of serotype O12 was similar to that of other serotypes and thus could not explain the susceptibility to fosfomycin. As a number of epidemiological studies using various methods, especially ribotyping with EcoRI, have shown that most strains are similar, it has been suggested that a single strain of this serotype is widespread. However, in this study ribotyping with EcoRI and PvuII distinguished seven clones among 24 ticarcillin resistant serotype O12 isolates, although one ribotype predominated (67%). Thus the hypothesis of spread of one clone across Europe cannot explain the common resistance phenotype observed in different clones of serotype O12. Resistance of beta-lactams and aminoglycosides might be explained by greater receptiveness for transposable resistance mechanisms, and susceptibility to fosfomycin by increased permeability of the outer membrane.

Anti-Bacterial Agents↗
PubMed1996

Short report: polymerase chain reaction detection of hepatitis E virus in north African fecal samples.

Epidemics of enterically-transmitted non-A, non-B hepatitis were described in 1983-1984 involving French soldiers in Chad and in 1979-1980 in residents of Algeria. Hepatitis E virus (HEV) was subsequently implicated by serology. In this study, the presence of HEV in patient stool specimens from both outbreaks and from sporadic cases in residents of Chad (1994) was documented. This virus was detected in fecal suspensions by antibody capture of the virus and reverse transcriptase-polymerase chain reaction amplification of the viral RNA in the 3' end of open reading frame 2. Two of five epidemic cases from Chad (1983-1984) were positive, as well as one of five sporadic cases from Chad (1994), and two of three epidemic cases from Algeria (1979-1980). Of these 13 patients, 12 had detectable anti-HEV IgG in their serum. These results confirmed that HEV was the cause of hepatitis in at least five of these 13 patients.

Africa, Northern↗
PubMed1996

[Viral hepatitis A with prolonged course in adults].

OBJECTIVE: The aim of this study was to determine the clinical and virological characteristics of patients with type A viral hepatitis and a protracted course. METHODS: Twenty-seven patients with hepatitis A virus and elevated serum ALT levels for more than 6 months were studied. Patients were tested for hepatitis C and E virus using conserved serums. RESULTS: A biological relapse was defined by a decrease of the serum ALT levels > or = 50% followed by a > or = 50% increase in the minimal value. Biological relapses occurred in all patients. The median time between the onset of the disease and the first relapse was 87 days. During relapse, jaundice and ascites were present in five and one patients, respectively. All patients recovered. Serum aminotransferase activities returned to the normal range in a median of 230 days. None of the 17 tested patients had hepatitis C virus antibodies. Sixteen patients were tested for hepatitis E virus antibodies; 8 were positive for IgG and one for IgM. Sixteen control patients with acute hepatitis A of short duration, matched for date and country of contamination, were also tested for antibodies to hepatitis E virus; 11 were positive for IgG and none for IgM. CONCLUSION: A protracted course of type A viral hepatitis is characterised by relapses with or without symptoms. The high frequency of a positive test for hepatitis E IgG associated with a negative test for IgM in patients with and without a protracted course does not suggest that hepatitis E virus plays a role in patients with a protracted course. These positive results might be due to either false positive results or to past contamination.

Adult↗
PubMed1995

[Prevention of hepatitis A and hepatitis B with vaccination].

In spite of low endemic levels in France, hepatitis A and hepatitis B remains major concerns for public health. Seroprevalence of antibodies against hepatitis A (anti-HAV), declining below 15% in the 20 years-aged subjects, highlights an increasing susceptibility to hepatitis A. Later in the life, HAV infections become more serious and expansive. Control measures against hepatitis B have nearly stopped HBV spread linked to blood transfusions and mothers to infants transmission. Now, common risk factors are first sexual exposure, then injecting drug use, especially among young people. Vaccination is recognized as the most effective process for prevention. Recombinant hepatitis B vaccines have taken the place of plasma-derived vaccines. Although non responder individuals and escape mutants of HBV may hamper vaccinal coverage, hepatitis vaccines are highly immunogenic in immunocompetent people, allowing simplified schedules and reduced HBsAg dosages for children. Inactivated HAV vaccines now licensed prove to be highly immunogenic after only one injection. Hepatitis B vaccination targeted on high risk groups remains imperative but inadequate for reducing hepatitis B occurrence. A universal hepatitis B vaccination program in childhood and early adolescence would nearly stop the spread of HBV in the populations before ten years. Likewise, hepatitis A vaccination of travelers to endemic areas, all individuals exposed to contaminations from fecal sources, and food handlers, could reduce the spread of HAV in the community but would not completely prevent outbreaks of hepatitis A. Advantages of universal immunization of babies are not proved yet. Implementation of preventive strategies first needs a comprehensive surveillance of viral hepatitis in France.

Hepatitis A↗
PubMed1995

[Prevention of hepatitis A and hepatitis B by vaccination].

In spite of low endemic levels in France, hepatitis A and hepatitis B remain major concerns for public health. Seroprevalence of antibodies against hepatitis A (anti-HAV), declining below 15% in the 20 years-aged subjects, highlights an increasing susceptibility to hepatitis A. Later in the life, HAV infections become more serious and expansive. Control measures against hepatitis B have nearly stopped HBV spread linked to blood transfusions and mothers to infants transmission. Now, common risk factors are first sexual exposure, then injecting drug use, especially among young people. Vaccination is recognized as the most effective process for prevention. Recombinant hepatitis B vaccines have taken the place of plasma-derived vaccines. Although non responder individuals and escape mutants of HBV may hamper vaccinal coverage, hepatitis vaccines are highly immunogenic in immunocompetent people, allowing simplified schedules and reduced HBsAg dosages for children. Inactivated HAV vaccines now licensed prove to be highly immunogenic after only one injection. Hepatitis B vaccination targeted on high risk groups remains imperative but inadequate for reducing hepatitis B occurrence. A universal hepatitis B vaccination program in childhood and early adolescence would nearly stop the spread of HBV in the populations before ten years. Likewise, hepatitis A vaccination of travelers to endemic areas, all individuals exposed to contaminations from fecal sources, and food handlers, could reduce the spread of HAV in the community but would not completely prevent outbreaks of hepatitis A. Advantages of universal immunization of babies are not proved yet. Implementation of preventive strategies first needs a comprehensive surveillance of viral hepatitis in France.

Adolescent↗
PubMed1994

[Current status of immunization in the Armed Forces: need of continuous adaptation of vaccinations against cerebrospinal meningitis, typhoid and hepatitis A].

The history of military medicine has always been closely linked with that of vaccinations. Doctors of Armed Forces, doctors of collectivities, have contributed to vaccination progresses in large amounts. But evolutions are often rapid here: epidemiological modifications, improvements in the existing vaccines or creation of new vaccines, diversification of military specificities. Three recent modifications in the vaccination schedule of the Armed Forces show this necessary adaptation: systematization of the meningococcal A+C vaccination during the incorporation, because of the modification of the disease's epidemiological profile; increase of the frequency in serogroup C with a mortality increase (9 cases of death out of 10 observed between 1991 and 1992); cancellation of antityphoid vaccination for recruits serving in home country. Indeed the disease has become rare in France, and this is often due to imported cases (3 cases in the Armed Forces in 1992); introduction in 1994 of vaccination against viral hepatitis A, systematic under the age of 25 years and after a serological selection above for servicemen having to serve overseas or for outside operations. These 3 examples show the necessity to have updated and adaptable vaccination schedules.

Bacterial Vaccines↗
PubMed1994

[Triple shigellosis in the same patient contracted during operation "Turquoise" in Rwanda].

We report a case of shigellosis observed in a young French sanitary assistant, returning from a refugees camp in Goma after a 5-week stay. Three different species were isolated from stool samples: Shigella flexneri, S. boydii and S. sonnei. This observation raises the matter of a chemical prophylaxis during a short stay in developing countries where sanitary conditions are poor.

Adult↗
PubMed1993

Mapping of linear B cell epitopes on open reading frames 2- and 3-encoded proteins of hepatitis E virus using synthetic peptides.

Hepatitis E virus (HEV) is the causative agent of non-A, non-B hepatitis which is transmitted by the fecal-oral route and occurs principally in the form of large epidemics and outbreaks in developing countries. Two overlapping synthetic peptides corresponding to overlapping DNA sequences of the ORF 3 of HEV genome were found to be immunoreactive with sera from patients involved in two epidemics of enterically transmitted non-A, non-B hepatitis. The results suggested the existence of two distinct epitopes. The four synthetic peptides representing these two epitopes from Burma and Mexico strains of hepatitis E virus, were used to investigate anti-HEV reactivities. HEV antibodies were detected in 84-88% of HEV-infected individuals according to the peptide used. The results suggest that a peptide-based ELISA can provide an accurate tool for the diagnosis of acute hepatitis type E.

Amino Acid Sequence↗
PubMed1993

Hepatitis E and hepatitis C virus infections among French soldiers with non-A, non-B hepatitis.

Serologic markers of HCV and HEV were investigated in 74 French soldiers with non-A, non-B hepatitis and in 18 patients involved in an outbreak of non-A,non-B hepatitis in Algeria. Moreover, anti-HCV antibodies were detected in 13 patients with non-A,non-B hepatitis of parenteral origin. HEV antibodies were investigated in 61-65% of patients involved in the 2 enterically transmitted outbreaks of non-A,non-B hepatitis observed in Algeria and Chad. The third cluster of non-A,non-B hepatitis observed in French soldiers serving in French Guyana is more likely to be attributed to malaria prophylactic treatment with Amodiaquine than to a viral origin. HCV infection was observed in 93% of acute or chronic cases associated with blood transfusion or parenteral drug abuse. Among acute cases, none of the soldiers who contracted the disease in Africa or in French Guyana was found to be anti-HCV positive compared to 78% of those who contracted the disease in France. HCV infections resulted in chronic hepatitis in 61% of cases.

Adult↗
PubMed1993

[Water and viral hepatitis].

The main agents responsible for acute viral hepatitis throughout the world are the hepatitis A virus (HAV) and the hepatitis E virus (HEV). Both are transmitted by fecal-oral route and can provoke large epidemics, HAV in developed countries and HEV in developing countries. Water is a major vehicle of spread. However, two different epidemiological patterns have to be distinguished: level of HAV excretion is short but high. Because of its resistance to physical and chemical agents, HAV remains infectious for a long time under environmental conditions. Progress in hygiene have nearly stopped the circulation of HAV in industrialized countries, making populations more susceptible to the infection and increasing the epidemic risk. Conventional measures sometimes fail to prevent HAV infections. Vaccine is currently the best way for hepatitis A prophylaxis; HEV is excreted briefly and at low concentrations. Viral particles are fragile in vitro and their viability in environment is not yet understood. Epidemics mainly occur in countries with poor sanitary conditions, resulting from heavy water pollutions. High case-fatality rates are observed, especially among pregnant women. The control of enterically transmitted viral hepatitis remains a major public health challenge. Virological surveillance of waste water could improve strategies based on hygiene, sanitation and supply of drinking water.

Feces↗
PubMed1993

[Realities of immunizations in the armed forces: necessity of continued adaptation of vaccinations against cerebrospinal meningitis, typhoid and hepatitis A].

The history of military medicine has always been closely linked with that of vaccinations. Doctors of Armed Forces, doctors of collectivities, have contributed to vaccination progresses in large amounts. But evolutions are often rapid here: epidemiological modifications, improvements in the existing vaccines or creation of new vaccines, diversification of military specificities. Three recent modifications in the vaccination schedule of the Armed Forces show this necessary adaptation: Systematization of the meningococcal A + C vaccination during the incorporation, because of the modification of the disease's epidemiological profile: increase of the frequency in serogroup C with a mortality increase (9 cases of death out of 10 observed between 1991 and 1992). Cancellation of antityphoïd vaccination for recruits serving in home country. Indeed the disease has become rare in France, and this is often due to imported cases (3 cases in the Armed Forces in 1992). Introduction in 1994 of vaccination against viral hepatitis A, systematic under the age of 25 years and after a serological selection above for servicemen having to serve overseas or for outside operations. These 3 examples show the necessity to have updated and adaptable vaccination schedules.

Bacterial Vaccines↗