Biomedical subjects

M F Paccaud

Publications and source records attributed to M F Paccaud.

At least 19 recordsLinked to original sources

PubMed1996

Surveillance of influenza in Switzerland between 1987 and 1995.

During 8 years of continuous influenza surveillance in Switzerland (1987 to 1995), influenza A viruses predominated during 5 seasons and influenza B viruses during 3. The most severe outbreaks occurred in the 1988/89 season (A/H1N1 subtype), in the 1989/90 season (A/H3N2 subtype) and in the 1994/95 season (simultaneous outbreak of influenza A/H3N2 and B). From 1987 to 1993, peak activity of influenza A viruses was observed during December and January (for 8 weeks on average) while influenza B viruses were most active between February and March (ordinarily for 6 weeks). During the 1994/95 season, however, simultaneously increased activity of both influenza A/H3N2 and B viruses was observed, peaking at the end of March and lasting for about 9 weeks. The variants predominant in Switzerland largely corresponded antigenically to those isolated elsewhere in Europe, but a delay of one year was often observed. New strains detected at the end of a season (herald viruses) made it possible to forecast the type or subtype of virus which would predominate the next season. Isolation rates for A/H3N2 viruses were significantly higher in the 10-19 years and 60-plus age groups, whereas there was no statistical difference between age groups for A/H1N1 viruses. A decreasing isolation rate, corresponding to increasing age, was found for influenza B viruses. Increased mortality was observed in patients over 65 during the period of high influenza A/H3N2 activity, as was especially evident during the 1989/90 season.

Adolescent↗

PubMed1995

[A look back at 2 mumps outbreaks].

Two studies are presented. The first one concerns a mumps outbreak in a kindergarten in Geneva in June 1991. Of 26 children, nine (34.6%) got mumps. Of nine children vaccinated with the Rubini vaccine strain, seven had the disease as opposed to only one of 14 children vaccinated with the Urabe strain. The vaccine efficacy of the Rubini strain was estimated at 22% with a 95% confidence interval of -10% to 45%. The second study concerns a cluster of 112 mumps patients seen by a pediatrician in the Bernese Jura region between September 1992 and May 1993. A case-control study was carried out resulting in a vaccine efficacy estimate of 50% with a 95% confidence interval of -19% to 81%. Of the cases, 51 (45.5%) had been vaccinated against mumps, 50 of them (98%) with the Rubini vaccine strain. Of the controls, 30 (61.2%) had been vaccinated, 86.7% of them with Rubini. Methodological problems of case selection and their possible effects on the estimated vaccine efficacy are discussed. The results of these two studies have been confirmed by more recent investigations. In retrospect, we therefore conclude that small studies can serve as early indicators for epidemiological evidence and that they can be finally integrated into a more complete picture.

Child↗

PubMed1991

Immunohistochemical detection of chlamydiae in formalin-fixed tissue sections: comparison of a monoclonal antibody with yolk derived antibodies (IgY).

Immunohistological detection of chlamydiae in formalin-fixed and paraffin-embedded sections of various organs from several species is described. In a retrospective study, two antisera, a commercially available monoclonal murine antibody (IgMur) and vitelline immunoglobulins (IgY), extracted from the egg yolk of immunized hens, were compared and tested for their applicability under routine condition. Both antisera were applied to tissues from which chlamydiae had been isolated or in which the presence of chlamydiae had been suspected in specially stained sections. Antigen labelling was optimal with the monoclonal antibody. Vitelline immunoglobulins produced some unspecific reactions, especially in lung tissue sections. Because of the antigenic relationship between the vitelline antibodies and tissues of birds, IgY are not suitable for the detection of psittacosis on avian substrates, when using an indirect immunological method. Staining in other tissues e.g. intestine or placenta was of equal quality as that attained with monoclonal antibodies. Depending on the advantages and disadvantages in every individual case, one of the two antibodies may be chosen for further studies. Vitelline antibodies should be preferred with respect to animal welfare.

Animals↗

PubMed1986