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Antonio Giulivi

Publications and source records attributed to Antonio Giulivi.

12 recordsLinked to original sources

Epidemiological study of Creutzfeldt-Jakob disease death certificates in Canada, 1979-2001.

INTRODUCTION: A descriptive epidemiological analysis to update trends of Creutzfeldt-Jakob disease (CJD) deaths, from 1979-2001, was undertaken. METHODS: Cases with CJD as underlying cause were extracted. Age-adjusted death rates by age, sex, and province were calculated. Information on birthplace, autopsy indications and type of work were examined for death certificates from 1979 to 1997. RESULTS: 462 cases were identified between 1979 and 1997. The average annual age-standardized mortality rate was 0.93 deaths per million persons during this period and 1.03 for 1998-2001. Persons 60 years or older demonstrated the highest average annual mortality rate. Rates were slightly higher among males and increased with age. Persons born in Canada accounted for 72% of deaths. Cause of death was verified by autopsy for 9.1% of patients while 21% of deaths indicated that additional information relating to underlying cause was expected. The service industry occupation represented the largest mortality (Quebec does not capture these data). CONCLUSIONS: Canadian rates are consistent with those of the United States and slightly higher than those of certain European countries. Approximately 44% of CJD cases had an autopsy record, though many were incomplete. We are unable to determine a relation with occupation. We recommend annual analysis of CJD death registrations for updated surveillance of trends, as mortality data are an efficient tool for monitoring incidence.

Adolescent↗

Occult hepatitis B virus infection in a North American adult hemodialysis patient population.

Hepatitis B virus (HBV) infections continue to occur in adult hemodialysis units. A possible contributing factor is the presence of occult HBV (serum hepatitis B surface antigen [HBsAg] negative but HBV DNA positive). Two hundred forty-one adult hemodialysis patients were screened for occult HBV. HBV DNA testing was performed by real-time polymerase chain reaction (PCR) with 2 independent primer sets (core promoter and surface). Two (0.8%) of the 241 patients were HBsAg positive. Of the remaining 239 HBsAg-negative patients, 9 (3.8%) were HBV DNA positive. Viral loads in these individuals were low (10(2)-10(4) viral copies/mL). Seven of the 9 (78%) were nt 587 mutation (sG145R mutant) positive. Demographic, biochemical, and HBV serological testing did not help to identify those with occult HBV. In conclusion, the prevalence of occult HBV in adult hemodialysis patients in this North American urban center is approximately 4 to 5 times higher than standard HBsAg testing would suggest. The majority of these infections are associated with low viral loads and a high prevalence of the sG145R mutant. Finally, the demographic, biochemical, and/or serological features of HBV DNA-positive subjects do not distinguish these individuals from the remainder of the dialysis patient population.

Adult↗

Genomic analysis of a recently identified virus (SEN virus) and genotypes D and H by polymerase chain reaction.

BACKGROUND/AIMS: SEN virus (SENV) was discovered in 1999 as a DNA virus with hepatotropic properties. Nine genotypes (A-I) have been identified with genotypes D and H being more prevalent in cases of chronic hepatitis. Attempts to determine whether SENV causes liver disease have been hampered by limited diagnostic testing. METHODS: In the present study, we developed two PCR based assays; a general SENV screening and genotype-specific assay. RESULTS: By screening PCR, the specificity for all SENV genotypes and SENV-related sequences was 20/20 (100%) with confirmation of the results being provided by genomic sequencing. With the genotype-specific PCR, specificities for SENV-D and SENV-H were 7/7 (100%) and 7/11 (64%), respectively. All screening PCR products were cloned and sequenced. The results of sequencing showed high genetic diversity in representative SENV genotypes. Five of twenty patients (25%) had mixed infections with several SENV genotypes. CONCLUSIONS: The screening PCR was useful for identifying cases of SENV infection. However, because of high genetic divergence and mixed co-infection, it was difficult to establish a specific method for genotype distinction. Hence, sequencing is still required for further investigations of SENV as a potential cause of liver disease.

Amino Acid Sequence↗

Comparison of DNA amplification, mRNA amplification, and DNA hybridization techniques for detection of cytomegalovirus in bone marrow transplant recipients.

A total of 676 specimens from 63 recipients of bone marrow allografts were tested for cytomegalovirus (CMV) by the following assays: CMV pp67 NucliSens (NS), AMPLICOR CMV MONITOR (RA), and the Digene CMV DNA test (DG). In a consensus analysis, the sensitivities and specificities were 60 and 99% (NS), 96 and 98% (RA), and 90 and 76% (DG), respectively; for detection of symptomatic CMV infection, they were 60 and 97% (NS), 65 and 97% (RA), and 95 and 77% (DG), respectively. In multivariate analysis, the major risk factor for symptomatic CMV infection was an increase in the viral load in the DG assay; in univariate analyses, maximum viral loads in both DG and RA assays and a rising viral load in the RA assay were also significant. The earliest detection of CMV replication was provided by the RA assay (mean, 39 days posttransplantation), followed by the DG assay (mean, 48 days) and the NS assay (mean, 58 days).

Adolescent↗

Insights into SEN virus prevalence, transmission, and treatment in community-based persons and patients with liver disease referred to a liver disease unit.

To document the prevalence and routes of transmission of SEN virus (SEN-V) in community-based individuals and patients referred to a liver disease unit, stored serum samples obtained from 160 Canadian Inuit and 140 patients with liver disease were tested for SEN-V DNA by polymerase chain reaction. In the community-based population, SEN-V was present in 57 (36%) of 160 persons. SEN-V-positive individuals tended to be younger and were more often male. Liver enzyme levels and serologic markers for hepatitis A and B viruses were similar in SEN-V-positive and SEN-V-negative individuals. SEN-V was present in 30 (21%) of the 140 patients with liver disease. Age, sex, risk factors for viral acquisition, prevalence of symptoms, and liver biochemical and histological findings were similar in SEN-V-positive and SEN-V-negative patients. These results indicate that SEN-V infection is a common viral infection in both healthy individuals and patients with chronic liver disease, that transmission likely occurs via nonparenteral routes, and that SEN-V infection is not associated with higher rates of or more-severe liver disease in persons with preexisting liver disease.

Adult↗

Effectiveness of leucoreduction for removal of infectivity of transmissible spongiform encephalopathies from blood.

In 1999, the UK implemented universal leucoreduction as a precaution against transmission of variant Creutzfeldt-Jakob disease by transfusion of domestic blood or red blood cells. We aimed to assess how effectively leucoreduction reduced infectivity of transmissible spongiform encephalopathies (TSEs) in blood. 450 mL of whole blood collected and pooled from scrapie-infected hamsters was leucoreduced with a commercial filter. Blood cell concentrations were quantified, and infectivity titres measured. Blood cell recovery and white blood cell removal complied with American Association of Blood Banks standards. Leucofiltration removed 42% (SD 12) of the total TSE infectivity in endogenously infected blood. Leucoreduction is necessary for the removal of white-cell-associated TSE infectivity from blood; however, it is not, by itself, sufficient to remove all blood-borne TSE infectivity.

Animals↗

Hepatitis A, B, and C in Canada. Results from the National Sentinel Health Unit Surveillance System, 1993-1995.

OBJECTIVES: To estimate the incidence of and to describe the risk factors that were associated with the acquisition of hepatitis A, B, and C in well-defined Canadian populations from the Sentinel Health Unit Surveillance System (SHUSS). METHODS: We used the 1993 to 1995 data on hepatitis A, B, and C infection in Canada, collected by SHUSS, a national surveillance system established by the Laboratory Centre for Disease Control in Health Canada in 1993, through consultation and collaboration with provincial partners. We calculated the rates of, and described and discussed the risk factors that were associated with, hepatitis A, B, and C infection, based on the SHUSS surveillance data. RESULTS: From 1993 to 1995, SHUSS reported 92 cases of hepatitis A, 89 hepatitis B, and 720 hepatitis C, yielding a rate of 3.9, 3.8, and 30.3 per 100,000, respectively. The reported rates varied substantially among participating health units, ranging from 0.8 to 8.1 per 100,000 for hepatitis A, 0.0 to 9.0 for hepatitis B, and 5.4 to 73.3 for hepatitis C. The most frequently reported risk factor for hepatitis A was a history of street drug use, followed by recent international travel and household contact with a hepatitis A case, household crowding, and a history of raw or undercooked shellfish consumption. The most frequently reported risk factors for the acquisition of hepatitis B included history of street drug use and occupational exposure. The most frequently reported risk factor for the acquisition of hepatitis C was a history of street drug use, followed by health care exposure and occupational exposure. Only 5% of persons with hepatitis B infection had a history of hepatitis B immunization. INTERPRETATION: Despite the limitations of possible bias due to selective participation of SHUSS and the lack of information on risk factors among controls, the high exposure to known risk factors and the low rate of vaccination among hepatitis patients can provide useful information for the development of public health policies to control hepatitis A, B, and C infection in Canada.

Canada↗

Development of a computer linkage system for a blood recipient notification program in Nova Scotia.

OBJECTIVES: To assess the potential uses of computer-assisted record linkage in the surveillance of infectious diseases, using the Nova Scotia blood recipient notification program as the example. METHODS: We developed a computer-assisted, multiple-pass, probabilistic record linkage to link records for blood recipients identified by the Nova Scotia notification program (Nova Scotia Phase I Blood Bank File information) with corresponding Nova Scotia Health Card Registration File records to obtain current mailing addresses to contact potentially living recipients. We used variables available from both files (e.g., name, date of birth, gender, and health care registration number) to link records, after eliminating duplicates/deceased cases. RESULTS: Among 23,925 eligible records in the Nova Scotia Phase I Blood Bank File (1984-1990), there were 1,818 (7.8%) duplications and 8,675 deceased cases, leaving 13,432 cases for linkage. 8,713 (65%) cases were successfully linked to the 1998 Health Card Registration Data File for current mailing addresses. INTERPRETATION: Multiple-pass linkage seems acceptable for maximizing detection of correctly matched records for look-back projects. To overcome quality/lack of information obstacles, future look-back linkages should explore the use of supplementary data files (tax files, voter lists, license files, other provincial databases) to obtain most current addresses.

Disease Notification↗

An epidemiologic study of hepatocellular carcinoma in Canada.

BACKGROUND AND METHODS: To provide information on poorly described Canadian hepatocellular cancer epidemiology, we analyzed incident cases abstracted from the Canadian Cancer Registration Database (1969-1997) and Canadian annual death data (1969-1998). Age, sex, geographic distribution, and secular trends were described. Projection models were developed for the next decade. RESULTS: Results indicated much higher incidence and mortality rates in males than females, with substantial increases for both with age. Age-standardized incidence rates increased an average of 3.4% per year in males, 1.2% per year in females (1969-1997). Age-standardized mortality rates increased an average of 1.48% in males, but decreased an average of 0.46% per year in females (1969-1998). Join-point analysis of the linear trends in the age-standardized incidence and mortality rates suggested that a new trend started to emerge about 1991. The fitted non-linear multiplicative model predicted the occurrence of 1,565 new cases and 802 deaths in the year 2010. HCC incidence was the highest in British Colombia, followed by Quebec, and the lowest in the Atlantic region. CONCLUSIONS: Incidence rates of hepatocellular carcinoma have increased substantially, consistent with the reported increase in the prevalence of Hepatitis C Virus (HCV) and Hepatitis B Virus (HBV) infections in recent decades.

Canada↗

Hepatitis C update.

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Canada↗

Physician survey on knowledge and reporting practices of transfusion-transmitted infections in Canada.

OBJECTIVE: To assess physicians' knowledge and reporting practices of transfusion-transmitted infections (TTI). DESIGN: Cross-sectional postal survey. TARGET POPULATION: Family physicians and specialists. METHODS: A survey questionnaire was sent by mail to 1,359 randomly selected physicians across Canada, and was followed up by a reminder telephone call. RESULTS: A total of 546 (40%) physicians completed and returned the questionnaire. The data from 512 eligible practitioners across Canada were analyzed. Almost all physicians were knowledgeable on the transmission of HIV, HBV and HCV through blood and plasma derivatives. However, physicians' knowledge, particularly the family physicians', was generally lower for less well-known TTIs. For example, only 7.2% of family physicians recognized Babesiosis as a TTI. Of the total 318 physicians who have encountered patients with possible TTI, 50% of them reported such cases to public health or other authorities and many reported to more than one organization. Of the total 159 non-reporting physicians, 91.1% explained that the cases were already reported by laboratories or other physicians. More than 90% of respondents think that it is important or very important that physicians report the cases of TTI to public health authorities for the purpose of surveillance, and more than 80% of them think that it is important or very important to include TTI as a separate entity in the communicable diseases surveillance systems. CONCLUSION: The majority of physicians recognize the more common TTIs and only 50% of them reported such cases. The majority of physicians support the reporting of TTI to public health authorities for surveillance. Recommendations are made to increase physicians' knowledge and reporting of TTI.

Canada↗