Search results for "disease outbreak"
showing 10 items of 175 documents
Syphilis 2001 a palaeopathological reappraisal
2002
The origin and subsequent spread of the treponematoses, especially that of venereal syphilis, has been the subject of considerable scientific attention. Various theories were put forth and palaeopathological specimens were used for their validation in recent times. One influential contribution was the paper by Baker & Armelagos in 1988. Numerous new findings and results on both sides of the Atlantic call for a new evaluation of the available osseous material. A review of the recent literature leads to the suggestion of a worldwide distribution of non-venereal treponemal disease since the emergence of Homo and to a first epidemic outbreak of venereal syphilis in Europe of the late 15th and t…
Phylogenetic analysis in the clinical risk management of an outbreak of hepatitis C virus infection among transfused thalassaemia patients in Italy
2021
Background: Occurrence of hepatitis C virus (HCV) infection is reduced by effective risk management procedures, but patient-to-patient transmission continues to be reported in healthcare settings. Aim: To report the use of phylogenetic analysis in the clinical risk management of an HCV outbreak among 128 thalassaemia outpatients followed at a thalassaemia centre of an Italian hospital. Methods: Epidemiological investigation and root-cause analysis were performed. All patients with acute hepatitis and known chronic infection were tested for HCV RNA, HCV genotyping, and NS3, NS5A, and NS5B HCV genomic region sequencing. To identify transmission clusters, phylogenetic trees were built for each…
Detection of spatial disease clusters with LISA functions.
2011
Detection of disease clusters is an important tool in epidemiology that can help to identify risk factors associated with the disease and in understanding its etiology. In this article we propose a method for the detection of spatial clusters where the locations of a set of cases and a set of controls are available. The method is based on local indicators of spatial association functions (LISA functions), particularly on the development of a local version of the product density, which is a second-order characteristic of spatial point processes. The behavior of the method is evaluated and compared with Kulldorff's spatial scan statistic by means of a simulation study. It is shown that the LI…
Bayesian hierarchical Poisson models with a hidden Markov structure for the detection of influenza epidemic outbreaks
2015
Considerable effort has been devoted to the development of statistical algorithms for the automated monitoring of influenza surveillance data. In this article, we introduce a framework of models for the early detection of the onset of an influenza epidemic which is applicable to different kinds of surveillance data. In particular, the process of the observed cases is modelled via a Bayesian Hierarchical Poisson model in which the intensity parameter is a function of the incidence rate. The key point is to consider this incidence rate as a normal distribution in which both parameters (mean and variance) are modelled differently, depending on whether the system is in an epidemic or non-epide…
Bayesian Markov switching models for the early detection of influenza epidemics
2008
The early detection of outbreaks of diseases is one of the most challenging objectives of epidemiological surveillance systems. In this paper, a Markov switching model is introduced to determine the epidemic and non-epidemic periods from influenza surveillance data: the process of differenced incidence rates is modelled either with a first-order autoregressive process or with a Gaussian white-noise process depending on whether the system is in an epidemic or in a non-epidemic phase. The transition between phases of the disease is modelled as a Markovian process. Bayesian inference is carried out on the former model to detect influenza epidemics at the very moment of their onset. Moreover, t…
Prospective surveillance of multivariate spatial disease data
2012
Surveillance systems are often focused on more than one disease within a predefined area. On those occasions when outbreaks of disease are likely to be correlated, the use of multivariate surveillance techniques integrating information from multiple diseases allows us to improve the sensitivity and timeliness of outbreak detection. In this article, we present an extension of the surveillance conditional predictive ordinate to monitor multivariate spatial disease data. The proposed surveillance technique, which is defined for each small area and time period as the conditional predictive distribution of those counts of disease higher than expected given the data observed up to the previous t…
Pandemic influenza A/H1N1 virus in a swine farm house in Sicily, Italy.
2012
This report describes a pandemic A/H1N1 (H1N1 pdm) virus outbreak occurred in December, 2009 in a swine farm used as research facility (Istituto Mediterraneo Trapianti e Terapie ad Alta Specializzazione) for preclinical studies, located in Sicily, Italy. All the 13 pigs of the farm, showed cough, fever, inappetence and weakness. At the same time, an unvaccinated worker of the stabling showed influenza-like symptoms. RNAv extracted from two swabs collected from infected pigs resulted positive by Real Time RT-PCR for Influenza A virus. Furthermore, after growth on embryonated eggs, viral isolates were identified by Real Time RT-PCR specific for H1N1 pdm virus and characterized antigenically. …
New Coronavirus (SARS-CoV-2) Crossing Borders Beyond Cities, Nations, and Continents: Impact of International Travel
2021
The third outbreak of coronavirus in the form of the COVID-19 infection started in Wuhan, China, in December 2019. The early and rapid spread of this infection across borders can be largely attributed to international air travel that has become a part of modern globalization. In this article, we analyze the spread of the novel coronavirus (SARS-CoV-2) along the routes of international travel, both by air and by sea. Pitfalls of various screening methods used at the airports and the importance of optimal aircraft ventilation are discussed. Also, we suggest measures that can be taken to reduce the risk of transmission associated with air travel.
Analysis of integrated virological and epidemiological reports of norovirus outbreaks collected within the Foodborne Viruses in Europe network from 1…
2008
ABSTRACT The Foodborne Viruses in Europe network has developed integrated epidemiological and virological outbreak reporting with aggregation and sharing of data through a joint database. We analyzed data from reported outbreaks of norovirus (NoV)-caused gastroenteritis from 13 European countries (July 2001 to July 2006) for trends in time and indications of different epidemiology of genotypes and variants. Of the 13 countries participating in this surveillance network, 11 were capable of collecting integrated epidemiological and virological surveillance data and 10 countries reported outbreaks throughout the entire period. Large differences in the numbers and rates of reported outbreaks pe…
Decontamination of a barrier facility using microisolator cages and provisional partitioning
2007
In 2000, the authors found endemic infections of mouse hepatitis virus, minute virus of mice, Syphacia obvelata, and Myobia musculi among mice in a large barrier facility at the University of Mainz. To eliminate the infections, they subdivided the facility into two distinct hygiene units. However, architectural constraints made it impossible to completely separate the HVAC systems of both hygiene units and to establish adequate personnel locks. To compensate for these suboptimal barrier conditions of the two newly established units, the authors replaced the open-top caging and open-servicing system with filter-top cages that were manipulated in cage-changing stations. The authors then depop…