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A Giovannini

Publications and source records attributed to A Giovannini.

At least 19 recordsLinked to original sources
PubMed2005

The use of homologous antigen in the serological diagnosis of brucellosis caused by Brucella melitensis.

In the European Union the serological diagnosis of brucellosis caused by Brucella melitensis is performed using the heterologous antigen of B. abortus S99. The possible higher sensitivity or ability of an early detection of antibodies by a homologous antigen may prove very useful in the final phases of an eradication programme. Results obtained in sheep experimentally infected by B. melitensis biovar 3 were compared using B. abortus S99, B. melitensis M1, M2 and M3 antigens in the Rose Bengal plate test (RBPT), the complement fixation test (CFT) and an enzyme-linked immunosorbent assay (ELISA) test. Forty-six sheep from an officially brucellosis-free flock were experimentally infected intraconjunctivally with B. melitensis biovar 3. Prior to infection, all animals were tested first against Brucella antibodies, weekly for 2 months post-infection (PI) and then monthly for a further 7 months. All sera were tested against the antigens listed above using RBPT, CFT and ELISA. Using a Bayesian approach, test sensitivities were estimated and compared. Their ability for the early detection of antibodies was evaluated through a regression model based on a logit response model, using the number of days PI as the independent variable and the logit of the fraction of positive animals as the dependent variable. No significant differences were detected among the various antigens used, either in terms of sensitivity or in terms of antibody kinetics; however, the CFT was significantly less sensitive than the RBPT and ELISA and it also showed a lower rate of increase of percentage positive animals (beta-coefficient of regression analysis).

Animals↗
PubMed2005

Statistical evaluation of classical swine fever surveillance plans in Italy (1995-2003).

Summary Surveillance plans were carried out in Italy from 1995 to 2003, with the main aim of controlling the possible circulation of low-virulence classical swine fever viral strains. The repetition of a serological monitoring programme over several years, with constantly negative results, can prove the absence of the infection while increasing the degree of confidence. In our case, in 2003, after eight repetitions of the surveillance plan, the probability that there was at least one infected farm reached 0.006%. Therefore, on the basis of the results of the sampling carried out from 1995 to 2003, we may state that there is no endemic infection, even because of a low virulence virus, in continental Italy.

Animals↗
PubMed2005

Reliability evaluation of sampling plan fixed by Council Directive 91/68/EEC for the maintenance of officially brucellosis-free flock status.

The European Union (EU) strategy with respect to sheep and goat brucellosis aims to eradicate the infection and achieve officially brucellosis-free (OBF) status in all EU holdings and territories. Council Directive 91/68/EEC of 28 January 1991 states that to maintain OBF status of ovine or caprine holdings located outside an OBF territory, only a representative number of animals need to be tested annually. However, depending on the number of animals in a holding, this testing method risks non-detection of the infection, thereby reducing the efficacy of the brucellosis control plan. The recommended sampling procedure has a low sensitivity for detecting infection in medium-sized flocks; furthermore, the risk of not detecting re-infection in OBF flocks, particularly in territories that have not yet gained OBF status, is also not acceptable. Moreover, in large-sized flocks, the Directive sampling procedure entails taking an excessive number of samples, which can be very expensive. The authors evaluated, by using statistical analyses and a simulation model based on field data, the possible consequences of the current EU strategy. It is suggested that the sampling criteria for the maintenance of OBF status in the EU should be modified and that a statistically based sampling method should be applied instead of the fixed percentage method that is currently in use.

Animals↗
PubMed2005

Comparison of BSE prevalence estimates from EU countries for the period July to December 2001 to the OIE and EU GBR classifications.

Consequent upon the bovine spongiform encephalopathy (BSE) crisis, the European Union (EU) Commission enacted various decisions, which demanded that all bovine animals over 30 months of age should be examined by one of the approved rapid tests when slaughtered for human consumption. All cattle over 24 months of age subject to 'special emergency slaughtering' or died on the farm or in transit or suspect of BSE infection should also be examined by one of the approved rapid tests. According to a specific commission decision, Sweden and Finland were to test only a sample of bovine animals over 30 months of age subject to normal slaughter. Testing commenced on 1 January 2001. The authors evaluate the results of more than 5 million tests performed in the second semester 2001 from across the EU. The prevalence of BSE in the risk categories considered (emergency slaughter, fallen stock and healthy slaughtered), and the probability distribution of true-positive, false-positive and false-negative results are estimated by second-order Bayesian analysis. The results of the validation of tests performed in the EU are also considered by estimation of the probability distribution of their sensitivity and specificity. The prevalence of infection estimated in the cattle population of each EU country is compared against the criteria given in the OIE Terrestrial Animal Health Code and is also used to evaluate the consistency of the results of EU Geographical BSE Risk with the actual infection levels in the countries. Finally, the capability of the two current approaches to BSE surveillance (i.e. the testing of all slaughtered and dead cattle as applied in the EU and a surveillance system targeted at animals in risk categories only) to detect the infection in a given population are discussed.

Animals↗
PubMed2005

The persistence of Brucella melitensis in experimentally infected ewes through three reproductive cycles.

The authors studied the persistence of infection in 46 ewes experimentally infected with Brucella melitensis biovar 3 and monitored through three subsequent reproductive cycles. The entire experimental period lasted for 151 weeks. Infection of ewes and elimination of Brucella in milk, or its presence in vaginal discharges, persisted throughout the duration of the trial, as demonstrated by recurrent elimination of Brucella in milk and vaginal discharges. Brucella melitensis was recovered from the tissues of one ewe killed at the end of the trial. The strain was recovered from vaginal swabs and milk following parturition in the third reproductive cycle from an ewe that had aborted in the first cycle but was not pregnant in the second cycle. From a public health point of view, the periodical recovery of Brucella from the milk during the entire trial period illustrated that brucellosis in sheep remains a continuous occupational risk and a significant public health problem for consumers of fresh milk and milk products. That risk may persist for at least 3 years following the initial infection of the flock. Lamb antibody titres became negative in all lambs within 5 months after birth. This suggested that serological tests on lambs may have no practical diagnostic significance if performed during the first 5 months of life. Nevertheless, the birth of three infected lambs suggested that the phenomenon of latent carrier state may represent another way for B. melitensis to persist in a flock.

Animals↗
PubMed2005

Correlation between animal and human brucellosis in Italy during the period 1997-2002.

The aim of this study was to test the hypothesis that brucellosis in Italy is a food-borne, rather than an occupational disease. This hypothesis was tested using data for both human and animal populations from the period 1997-2002. The correlation between the distribution of the disease in the human, sheep and goat populations was analysed, as were the risk factors for the disease, with respect to gender, age, occupation and residence of the individuals involved. Notifications of human brucellosis, which are mandatory in Italy, reach a peak between April and June. However, considering the standard incubation period of 2-4 weeks, and the fact that lamb slaughter is traditionally at a peak during the Easter period, it might be expected that occupational exposure would result in a peak of human cases between March and May. The observed peak between April and June could be related to the production and consumption of fresh cheese, starting just after lamb slaughter. The age of patients showed a fairly uniform distribution, and analysis of incidence rates of human brucellosis between 1997 and 2002 showed that the incidence rates were consistent with an occupational exposure risk of about 25%.

Adolescent↗
PubMed2004

Vaccination in the control strategy of bluetongue in Italy.

The incursion of bluetongue (BT) in Italy, in August 2000, caused heavy economic losses, partly due to the direct effect of the disease on the animals, but mostly due to indirect losses due to ruminant movement restrictions conducive to heavy losses to the cattle and sheep industry. To limit losses due to both disease and virus circulation, which was the cause of movement restrictions, the Italian Ministry of Health in May 2001 ordered the vaccination of animals of all domestic ruminant species in infected and "at risk" areas. The vaccination strategy derived from a risk assessment that suggested that the vaccination of all domestic ruminants could reduce both direct losses and virus circulation significantly. The different levels of vaccination coverage, achieved in the various regions of Italy, had clear consequences on the spread of both disease and infection. In regions where more than 80% of the target populations were vaccinated properly, the disease disappeared almost completely and virus circulation was significantly reduced, as documented by the serological surveillance system, after a single vaccination cycle. This led to a significant decrease in the areas subject to movement restrictions. Data generated by both field and controlled experiments contributed to modify the EU approach to BT and to some of the conclusions of the Third OIE International Symposium on Bluetongue that will probably lead to a modification of the Office International des Epizooties (OIE) standard.

Animals↗
PubMed2003

The effect of climate on the presence of Culicoides imicola in Italy.

A model was developed to classify the Italian territories in relation to their suitability to harbour populations of Culicoides imicola and, as a consequence, also able to sustain a bluetongue (BT) epidemic. Italy was subdivided into 3507 10 x 10 km cells. In 546 cells at least one collection was made. The cell was considered the unit for all subsequent analyses. Culicoides were collected using Onderstepoort-type blacklight traps. Some traps were operated weekly at chosen sites; the remainder were moved almost daily to new sites. Only the results obtained during the peak August-November period were used, to exclude bias caused by the seasonality of C. imicola. Climate data for the period 1999-2001 were obtained from 80 weather stations. Multiple logistic regression was performed using the presence or absence of C. imicola in a specific cell as the dependent variable. Annual means of daily values for minimum temperature and minimum relative humidity, and the mean altitude above sea level, were the independent variables. The probability of occurrence of C. imicola in each grid cell was used to create a prediction map for Italy. The model was able to correctly classify 77.5% of the 546 grid cells in which at least one collection had been made. Culicoides imicola was found frequently through much of Sardinia, in parts of southern Italy, and further north along the Tyrrhenian coast, but was absent from along most of the Adriatic coast, and the internal mainland, and from most of Sicily. Six detailed maps are provided. Also mapped are areas where the probability of the occurrence of C. imicola is lower than 5%. This identification of possible mountainous C. imicola-free areas in central Italy could facilitate safer animal trade and transhumance, even if BT infections in traded animals or moving stock, were to go undetected. Needless to say this depends upon no cool-adapted species of Culicoides being involved in the transmission of BT disease.

Animals↗
PubMed2002

The macular thickness and volume in glaucoma: an analysis in normal and glaucomatous eyes using OCT.

PURPOSE: To evaluate macular volume in normal and glaucomatous eyes using Optical Coherence Tomography (OCT). METHODS: Fifty eyes of 30 patients (age: 49-68); 20 eyes normal, 15 eyes with early glaucoma and 15 eyes with advanced glaucoma have been studied with the commercially available OCT unit (OCT 2000) (Humphrey Zeiss, Dublin, CA, USA). All eyes were examined at a scan length of 3.44 mm vertically across the fovea. OCT macular retinal thickness maps were used to calculate macular volume. RESULTS: We observed significant differences between groups. Normals (7.35 +/- 0.455 mm3) and early glaucoma (7.09 +/- 0.475 mm3), each had significantly greater volume than subjects with advanced glaucoma (6.678 +/- 0.455 mm3). CONCLUSIONS: Volumetric analysis of macular thickness with OCT tomograms may be a useful method of documenting and monitoring patients with early glaucoma and advanced glaucoma. In our analysis, and according to the observations of other authors, OCT macular volumes correlates significantly with glaucoma status.

Aged↗
PubMed2001

Polypoidal choroidal vasculopathy in Italy.

PURPOSE: To report on the frequency and clinical features of polypoidal choroidal vasculopathy (PCV) in a consecutive series of elderly Italian patients presenting with macular exudation. METHODS: The authors conducted a retrospective study on a series of 194 consecutive patients 50 years or older with newly diagnosed exudative maculopathy and the presumed diagnosis of age-related macular degeneration (ARMD). Color and/or red-free photographs and fluorescein and indocyanine green angiography were performed in all patients. RESULTS: Of the 194 patients, 19 (9.8%) were diagnosed with PCV. The remaining 175 (90.2%) patients had ARMD complicated by choroidal neovascularization. No age or sex differences were observed between the two groups. The disease was unilateral in 103 (58.9%) of 175 ARMD cases compared with 15 (78.9%) of 19 PCV cases (P = 0.09). Nine (47.3%) of 19 patients with PCV had an extramacular choroidal neovascularization, compared with only 5 (2.9%) of 175 patients with ARMD (P < 0.0001). Significant drusen were present in the fellow eyes of 66 (64.1%) of 103 unilateral cases in the ARMD group and in 4 (26.7%) of 15 patients with unilateral disease in the PCV group (P = 0.006). CONCLUSIONS: Polypoidal choroidal vasculopathy is not an uncommon disease in Italy and should be suspected in patients presenting with extramacular lesions and no large drusen in the fellow eye.

Aged↗
PubMed2001

Importance of the traceability of animals and animal products in epidemiology.

Traceability of animals and animal products has become a priority for governments of the developed countries, due to consumer demand for comprehensive and integrated food safety policies. In addition to analysing the differences between traceback and traceability systems, the authors describe some applications of animal traceback systems and the principal characteristics of an animal identification and registration system. The importance of a traceability system for food-borne risk assessment and management, and the most recent approaches towards a comprehensive and integrated animal health and food safety policy are reported.

Animal Diseases↗
PubMed2000

Use of innovative methods in the eradication of bovine tuberculosis.

During final phases of eradication programmes, strains of Mycobacterium sp. not belonging to the tuberculosis complex increase their relative frequency and are responsible for positive skin test reactions. Moreover, the specificity of any indirect diagnostic test, such as the skin test, is never completely accurate, therefore even when tuberculosis infection is completely eradicated, a number of false positive reactions are to be expected. The aim of this paper is to evaluate the performances of traditional isolation/typing techniques, automatic isolation/typing techniques based on fluorimetric detection of bacterial growth (Bactec), skin tests and the -interferon test. Samples examined for the evaluation of test sensitivities originated from 154 infected animals belonging to 32 infected herds. Samples used as negative controls in the evaluation of test specificities originated from 86 animals of nine officially infection-free herds. The automatic isolation/typing technique based on fluorimetric detection of bacterial growth showed higher sensitivity than the traditional isolation typing technique. Moreover, it allowed a safer processing of bacterial cultures, decreasing the risk for laboratory workers. The observed performance of the gamma-interferon test was considered beneficial in that it increased the sensitivity of individual diagnosis within an infected herd, especially in 'problem herds', but its poor specificity did not improve detection of infected herds compared to the skin test.

Animals↗
PubMed2000

Optical coherence tomography in the assessment of retinal pigment epithelial tear.

PURPOSE: To study the findings of optical coherence tomography (OCT) in retinal pigment epithelial (RPE) tears. METHODS: Sixteen eyes of 16 consecutive patients with age-related macular degeneration complicated by RPE tear were studied using OCT. Fluorescein angiography also was performed. Thirteen eyes were at the acute stage and three eyes were at the scarring stage, still with a recognizable tear. RESULTS: Optical coherence tomography identified an RPE detachment (PED) with focal interruption of the RPE in all cases. Optical coherence tomography always highlighted a peculiar non-dome-shaped profile of the serous PED, as opposed to that of the PED not complicated by an RPE tear. A very intense hyperreflectivity was observed in the OCT scans performed through the retracted RPE. A deep hyperreflectivity under the line corresponding to the RPE was evident in the area of the bare choroid. No choroidal neovascularization could be visualized using OCT, either at the acute or at the scarring stages. CONCLUSIONS: Optical coherence tomography, a noncontact, noninvasive imaging technique, may be a useful tool, complementary to fluorescein angiography, in the clinical assessment of RPE tears.

Aged↗
PubMed2000

Spatial risk factors related to outbreaks of contagious bovine pleuropneumonia in northern Italy (1990-1993).

In October 1990, an outbreak of contagious bovine pleuropneumonia (CBPP) was reported in Italy after an absence of approximately one century. Since October 1990, ninety-four outbreaks have occurred in Italy, of which forty-seven were concentrated in three areas of northern Italy (Lombardy region). The disease was eradicated in September 1993. The data used for the analysis were obtained from the epidemiological investigations undertaken during the outbreaks of 1990-1993. The unit of interest for the analysis is the farm. Spatial segregation of infected and uninfected farms within the study area was determined through the Pielou index of segregation. Data from herds within the same set of outbreaks were analysed through logistic regression to identify factors which could be used to discriminate between infected and uninfected herds. The study indicated a clear spatial segregation between infected and uninfected herds. The results of the analysis do not indicate the mode of disease spread. However, the study demonstrated that both aerosol and indirect transmission of the infection could have occurred, as previously documented in Africa. The possibility that indirect transmission played a prominent role in the spread of CBPP in the region of Lombardy is a completely new suggestion. Further studies are required to understand the epidemiology of CBPP in regions with intensive farming and a relatively cold climate. In particular, three aspects require consideration; firstly, animal movement among neighbouring herds could produce a pattern of disease similar to the one produced by indirect transmission (this possibility was excluded in the epidemiological outbreak investigations conducted by field veterinarians). Secondly, the methods of spatial analysis used in this study have not been previously used in the field of veterinary epidemiology. Further validation of the efficacy of these methods is thus required. Thirdly, the epidemiology of CBPP under conditions of high animal density and a relatively cool climate, as encountered in Lombardy, requires further investigation.

Animals↗
PubMed2000

Implementation of a system for the regional management of animal health emergencies.

A telematic system to support decisions and operations in case of animal health emergencies has been designed and implemented in the Abruzzo region of Italy. The system aims to improve decision-making by Veterinary Services in the event of an outbreak of exotic disease. The system has been tested, first by a simulated outbreak of foot and mouth disease, and then during an outbreak of swine vesicular disease. Critical problems were detected and corrected in both cases.

African Horse Sickness↗
PubMed2000

Detection of tenascin-C in surgically excised choroidal neovascular membranes.

BACKGROUND: Increase of tenascin-C (TN-C) expression has been found in pathologic tissues in which angiogenesis occurs. The aim of this study was to investigate TN-C expression in human choroidal neovascularization (CNV). METHODS: Ten choroidal neovascular membranes were surgically removed from 10 patients with age-related macular degeneration (n=6) and multifocal choroiditis (n=4). All membranes underwent immunohistochemical evaluation using monoclonal antibodies against TN-C and factor VIII. RESULTS: All membranes were positive for TN-C, which was abundantly and diffusely expressed in the extracellular matrix. CONCLUSIONS: Our results support the concept that TN-C has a role in cell proliferation and neovascularization in humans. TN-C, as a marker of angiogenesis, may provide novel rationales for the development of pharmacologic therapies for neovascular disorders, particularly CNV.

Biomarkers↗