Contingency plan implementation.

BACKGROUND: Although the National blood system in Canada reduces the risk of inventory shortages the possibility of a blood supply shortage still exists. The Ontario Ministry of Health and Long-Term Care developed a provincial plan to manage blood transfusion needs and inventory in the event of a National blood shortage. The Ontario plan was developed to align with the National plan as well as other provincial plans in order to ensure consistency in blood management strategies across the country. The Ontario plan was released in 2008, along with a toolkit to aid hospitals in developing their facility specific plans. In the Champlain region of Ontario, a group of 16 hospitals worked collaboratively to develop a regional blood shortage plan. A provincial blood shortage simulation exercise was held in 2010 to test out these plans. METHOD: The Director of Transfusion Medicine of the largest facility in the group of 16 hospitals (The Ottawa Hospital) took the lead in the development of the regional blood shortage management plan. Working groups from all 16 sites contributed to the plan development. The proposed plan was presented to the Medical Advisory Committee for approval. RESULTS: The plan consists of activities relating to the severity of the supply shortage as defined by Amber, Red, Recovery and Green phases. The plan includes a communication plan for notifying stakeholders including patients whose treatment may be affected. Inventory management and triage guidelines are provided to reduce the demand for blood and to conserve inventory for those patients whose need is prioritized as highest. The regional blood shortage management plan was tested successfully during the provincial simulation exercise. CONCLUSION: Where regional hospitals work together to provide healthcare, it is beneficial to develop a standardized plan to provide guidance to hospital personnel in response to a blood supply shortage. A consistent plan will ensure patient care is provided in a consistent manner across a health region. Mock or simulation exercises can aid in testing plans and raising the awareness of stakeholders.

Serological evidence of hepatitis E virus infection in an indigenous North American population.

BACKGROUND: Hepatitis E virus (HEV) infections are thought to be uncommon in North America. Recently, HEV transmission has been reported following the consumption of deer meat. Because deer are closely related to caribou and caribou meat is a staple of the Canadian Inuit and the American Eskimo diet, the present study explored the seroprevalence of HEV infection in an isolated Canadian Inuit community. METHODS: Stored sera were thawed and tested for immunoglobulin (Ig) G and IgM anti-HEV by ELISA, and tested for HEV-RNA by reverse transcriptase polymerase chain reaction. RESULTS: The study consisted of 393 sera (representing approximately 50% of the community's inhabitants). Eleven samples (3%) were IgG anti-HEV-positive. Their mean age was 29+/-8 years and three were male. Two of 11 (18%) were also IgM anti-HEV-positive. All IgG anti-HEV-positive individuals were HEV-RNA-negative. Liver biochemistry was normal in all. Seven of 11 (64%) were also positive for anti-hepatitis A virus, five (46%) were hepatitis B virus seropositive and none (0%) were positive for anti-hepatitis C virus. There were no associations between infections with HEV and other hepatropic viruses. Serological testing was negative for HEV infection in 25 caribou from an adjacent region. CONCLUSION: The results of the present study showed that serological evidence of HEV infection was present in 3% of the observed Canadian Inuit population; the presence of IgM anti-HEV suggested recent infection and HEV did not appear to coinfect with other common hepatotropic viruses. The source of HEV infection in the population remains unclear. These findings are interesting but preliminary. Additional data are required to determine whether HEV infections are responsible for otherwise unexplained acute hepatitis in the Canadian Inuit population and visitors returning from northern North American communities.

Comparison of antibody- and cell-mediated immune responses after intramuscular hepatitis C immunizations of BALB/c mice.

Current treatments for hepatitis C infection have limited efficacy, and there is no vaccine available. The goal of this study was to compare the immune response to several immunization combinations against hepatitis C virus (HCV). Six groups of mice were immunized at weeks 0, 4, and 8 with different combinations of a candidate HCV vaccine consisting of 100 microg recombinant HCV core/E1/E2 (rHCV) DNA plasmid and/or 25 microg rHCV polyprotein and 50 microL Montanide ISA- 51. Four weeks after the last injection, all groups of mice were sacrificed and blood samples and spleens were collected for measuring the levels of specific HCV antibodies (total IgG, IgG1, and IgG2a). Cell proliferation and intracellular interferon-gamma were also measured. Among the groups of immunized mice, only the mice immunized with rHCV DNA plasmid, rHCV polyprotein, and montanide (group D) and mice immunized with rHCV polyprotein and montanide (group F) demonstrated a significant increase in the total IgG titer after immunization. IgG1 was the predominant antibody detected in both groups D and F. No IgG2a was detected in any of the groups. Proliferation assays demonstrated that splenocytes from group D and group C (rHCV DNA primed/rHCV polyprotein boost) developed significant anti-HCV proliferative responses. The combination of an rHCV DNA plasmid, rHCV polyprotein, and montanide induced a high antibody titer with a predominance of IgG1 antibodies and recognized the major neutralization epitopes in HVR1. In contrast, group C did not show an increase in anti-HCV antibodies, but did show a proliferative response.

Enhanced surveillance for childhood hepatitis B virus infection in Canada, 1999-2003.

Since hepatitis B virus (HBV) infection can have serious sequelae, especially if infection occurs during childhood, there is a continuing need to examine its epidemiology so as to inform control measures. We analyzed trends in disease incidence and patterns of hepatitis B virus (HBV) transmission in both Canadian-born and non-Canadian-born children from 1999 to 2003, through the Enhanced Hepatitis Strain Surveillance System. Amongst Canadian-born children, the incidence of newly identified HBV infection per 100,000 declined significantly during the study period from 1.4 in 1999, to 0.5 in 2003 (RR, 0.75 per year; 95% CI, 0.60-0.95). Amongst non-Canadian-born children, the incidence of HBV infection per 100,000 ranged from 9.4 to 16.3, during the study period (linear trend test, p=0.69). Poisson regression analysis revealed that non-Canadian-born children were more likely to have HBV infection (RR, 12.3; 95% CI, 7.6 to 19.8), than Canadian-born children. HBV infection was found to be more common among children emigrating from high endemic area, than among Canadian-born children. Current Canadian immunization policy should take into consideration the protection of all children against HBV infection, including those coming from countries where mass hepatitis B vaccination programs have still not been launched.

Creutzfeldt-Jakob disease mortality in Canada, 1998 to 2013.

BACKGROUND: Human prion diseases, known collectively as Creutzfeldt-Jakob disease (CJD), are fatal, infectious neurodegenerative disorders that occur in all human populations. OBJECTIVE: To summarize national surveillance data for CJD in Canada between January 1, 1998, and December 31, 2013. METHODS: Detailed investigations were conducted of individual suspected CJD cases, with collaboration between Canadian health professionals and investigators affiliated with a central CJD surveillance registry operated by the Public Health Agency of Canada. Data were collected on the clinical profile, family history, and results of paraclinical and laboratory investigations, including post-mortem neuropathological examination. RESULTS: A total of 662 deaths from definite and probable CJD were identified in Canadian residents during the study period, comprising 613 cases of sporadic CJD (92.6%), 43 cases of genetic prion disease (6.5%), 4 cases of iatrogenic CJD (0.6%), and 2 cases of variant CJD disease (0.3%). The overall crude mortality rate for sporadic CJD was 1.18 per million per year [95% confidence interval (CI): 1.08,1.27]. Age-specific rates ranged from 0.05 [95% CI: 0.03,0.08] in persons under 50 years of age to 7.11 [95% CI: 6.20,8.11] in those aged 70 to 79. A significant net upward trend in age-adjusted rates was observed over the study period. Standardized mortality ratios, calculated for 10 individual Canadian provinces with reference to national average mortality rates, did not differ significantly from 1.0. CONCLUSION: Creutzfeldt-Jakob disease remains rare in Canada, although mortality rates vary by two orders of magnitude between older and younger age groups. The upward trend in age-standardized sporadic CJD mortality rate over the study period can be better accounted for by gradually improving case ascertainment than by a real increase in incidence.

Transcriptional analysis of human peripheral blood mononuclear cells after influenza immunization.

Influenza A virus is a major cause of morbidity and mortality worldwide. There is a large knowledge base on the immune response to influenza. However, few studies have focused on global gene expression in immune cells after antigenic challenge. A better understanding of the host immune response is required for the development of more efficient means of prevention and treatment of influenza. In this study, global gene expression in peripheral blood mononuclear cells (PBMCs) after influenza immunization was analyzed. The differential gene expression in antigen-stimulated and non-stimulated PBMCs was determined by cDNA microarrays. To determine whether a specific gene profile was present during a proliferative memory cell response to influenza antigens, gene expression in response to PHA was compared with antigen-stimulated PBMCs. PHA induced the upregulation of 201 genes while influenza virus antigen upregulated more than triple that is 630 genes out of 1700 genes analyzed. Both influenza antigen and PHA commonly upregulated 138 genes. Interferon (IFN)-related genes were induced by influenza but not by PHA. The interferon-gamma induced protein precursor 10 (IP-10) was upregulated 27-fold while the interferon-induced 54 kDa protein exhibited a 13-fold increase. The following gene families were also selectively upregulated by influenza antigens: complement ligands and receptors, T cell activation genes, growth factors, genes related to antigen processing and inflammatory responses. With PHA, the genes TNF-R, CTSG, CD3 delta, C8B, CRF1 and CCR2 had higher expression compared with the viral antigen stimulation. Neutrophil defensins alpha-1 and two C-C chemokines, proteins MIP-1-beta and MIP-4, were among the genes upregulated by both PHA and influenza antigens. The results suggest that interferon-induced genes are one of the main transcriptional targets during the immune response to influenza virus.

Preventing the spread of hepatitis B and C viruses: where are germicides relevant?

Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the most prevalent bloodborne pathogens. Infections caused by these organisms can become chronic and may lead to liver cirrhosis and carcinoma. Limited chemotherapy is now available, but only HBV can be prevented through vaccination. Both viruses are enveloped and relatively sensitive to many physical and chemical agents; their ability to survive in the environment may not be as high as often believed. As a result, their spread occurs mainly through direct parenteral or percutaneous exposure to tainted body fluids and tissues. Careful screening of and avoiding contact with such materials remain the most effective means of protection. Nevertheless, the indirect spread of these viruses, although much less common, can occur when objects that are freshly contaminated with tainted blood enter the body or contact damaged skin. Germicidal chemicals are important in the prevention of HBV and HCV spread through shared injection devices, sharps used in personal services (such as tattooing and body piercing), and heat-sensitive medical/dental devices (such as flexible endoscopes) and in the cleanup of blood spills. Microbicides in vaginal gels may also interrupt their transmission. General-purpose environmental disinfection is unlikely to play a significant role in the prevention of the transmission of these viruses. Testing of low-level disinfectants and label claims for such products against HBV and HCV should be discouraged. Both viruses remain difficult to work with in the laboratory, but closely related animal viruses (such as the duck HBV) and the bovine viral diarrhea virus show considerable promise as surrogates for HBV and HCV, respectively. Although progress in the culturing of HBV and HCV is still underway, critical issues on virus survival and inactivation should be addressed with the use of these surrogates.

Late pseudo-exacerbation of myasthenia gravis due to ectopic thymoma invading lower cranial nerves.

Dysarthria, dysphagia and repeated aspiration in a 54-year-old woman diagnosed and treated for myasthenia gravis 7 years earlier were initially thought to represent a late exacerbation of myasthenia. A cervical mass invading the jugular foramen and causing multiple lower cranial nerve palsies was biopsied and found to represent invasive ectopic thymoma.

Xenotransplantation and the potential risk of xenogeneic transmission of porcine viruses.

The clinical success of allotransplantation and the shortage of donor organs have led to a proposal for the use of animal organs as alternative therapeutic materials for humans. In that regard, swine are preferable to non-human primates as a source of donor organs. While applications for clinical trials for xenotransplantation have not yet been received in Canada, several trials have already been authorized in the United States. A major concern, however, is the potential for xenogeneic transmission of viruses from animals to humans via organ, tissue, or cellular transplantation or via ex vivo exposure of humans to porcine biologic materials. Xenotransplantation allows viruses to bypass the normal immunological defense mechanisms of the recipient. Furthermore, the use of immunosuppressive drugs following transplantation may facilitate the xenogeneic transmission of zoonotic agents. Of porcine viruses, swine hepatitis E virus does not cause any clinical symptoms in the natural host but is a likely zoonotic agent that can infect humans and cause hepatitis. Porcine circovirus type 1 is prevalent in swine populations with no known association with clinical disease, while circovirus type 2 causes post-weaning multi-systemic wasting syndrome. Porcine endogenous retrovirus is integrated into the host chromosomes while porcine cytomegalovirus undergoes latent infection. Two additional porcine herpesviruses have recently been identified in swine and have been named porcine lymphotrophic herpesviruses. These herpesviruses can potentially become reactivated in human recipients after xenotransplantation. All in all, there are a number of viruses in swine that are of primary concern to screen and eliminate from xenotransplantation protocols. Epidemiology and the current knowledge on xenogeneic risk of these viruses are discussed.

Current hepatitis A status in Canada.

Hepatitis A, caused by the hepatitis A virus, occurs most frequently in developing countries, but also causes sporadic cases or outbreaks in industrialized countries. The most common route of transmission is fecal-oral. The incidence of hepatitis A varies with geography, and economic and environmental conditions. The epidemiological pattern of the disease has changed with improvements in hygiene and economic conditions. The incidence and prevalence of hepatitis A has decreased, while the average age of exposure and subsequent infection has increased. The present report describes the current status of hepatitis A in Canada. The incidence rate of reported cases in Canada varies from over 10/100,000 (1991) to 3.6/100,000 (1998), and is higher in males, 4.7/100,000 (1998), than in females, 2.5/100,000 (1998). The highest reported hepatitis A rates are in age groups 30 to 39 years and 40 to 59 years, and in British Columbia. Such information is important for assessing current immunization approaches and for decision-making about new preventive strategies against hepatitis A in Canada.

Epidemiology of hepatitis B in Canada.

OBJECTIVE: To provide a current and comprehensive review of the epidemiology of hepatitis B virus (HBV) in Canada. DATA SOURCES: Published and unpublished epidemiological studies and surveillance reports of the past decade, primarily from Canada were studied. Fifty reports addressing HBV surveillance, incidence and prevalence, transmission-associated risk factors, co-infections, and prevention strategies were reviewed. DATA SYNTHESIS: HBV infection is an important vaccine-preventable infectious disease in Canada. The incidence rate of clinically recognized, acute HBV infection in 1998/1999 was estimated to be 2.3/100,000 people or approximately 700 cases a year. The prevalence of HBV carriers is estimated to be 0.5% to 1.0% of the population, but varies substantially according to population-specific risk factors. Most acute HBV infections are associated with injection drug use or high risk heterosexual activities, but 20% to 30% of acute cases did not report any identified risk factors. Surveillance activities such as the National Notifiable Disease Reporting system provide information regarding trends and risk factors. The primary preventive strategy for HBV consists of universal immunization for preadolescents and/or infants. Other strategies, such as the universal prenatal screening and postnatal immunization, and the prevention of nosocomial acquisition, are also important. The recently described hepatitis B surface antigen (HBsAg) escape mutants may not be detected by current HBsAg test assays, and the existing HBV vaccines may not protect vaccinees from infections by such mutants. CONCLUSION: Ongoing surveillance and research are required to assess risk factors for HBV transmission, evaluate the effectiveness of immunization programs and monitor the impact of HBsAg escape mutants.

Enhanced surveillance of acute hepatitis B and C in four health regions in Canada, 1998 to 1999.

OBJECTIVE: To assess the incidence and risk factors for acute hepatitis B and acute hepatitis C in a defined Canadian population. PATIENTS AND METHODS: An enhanced surveillance system was established in October 1998 to identify cases of acute hepatitis B and C infections in four regions in Canada, with a total population of approximately 3.2 million people. Information on demographic and clinical characteristics, laboratory results and potential risk factors was collected using predefined questionnaires. RESULTS: A total of 79 cases of acute hepatitis B and 102 cases of acute hepatitis C were identified from October 1998 to December 1999, resulting in an incidence rate of 2.3 and 2.9/100,000 person-years, respectively. Males had higher incidence rates than females. The incidence of acute hepatitis B peaked at age 30 to 39 years for both males and females, whereas acute hepatitis C peaked at 30 to 39 years for males and 15 to 29 years for females. At least 34% of acute hepatitis B and 63% of acute hepatitis C were associated with injection drug use. Persons who were 15 to 39 years of age were more likely to report injection drug use as a risk factor. Heterosexual contact was reported to be a risk factor for 36.6% of acute hepatitis B cases and 3.5% of acute hepatitis C cases. CONCLUSIONS: The surveillance provides national incidence estimates of clinically recognized acute hepatitis B and C. Both hepatitis B and C are important public health threats to Canadians. Prevention efforts for both diseases should focus on injection drug use, especially for people aged 15 to 39 years. Risky sexual behaviour is also a major concern in prevention of hepatitis B in Canada.

Serological studies of West Nile virus in a liver transplant population.

BACKGROUND: Solid organ transplant populations are at increased risk for serious clinical manifestations of West Nile virus (WNV) infection. OBJECTIVE: To monitor liver transplant recipients during the 2003 WNV season in Manitoba and to identify incidence, clinical presentation and serology. METHODS: Serial blood specimens were obtained from adult patients followed at the liver transplant outpatient clinic between May 2003 and October 2003. Studies for WNV infection included immunoglobulin (Ig) G and IgM enzyme immunoassay (EIA), hemagglutination inhibition (HI), plaque reduction neutralization test and reverse transcriptase-polymerase chain reaction. RESULTS: None of the 79 patients had clinical presentations suggestive of WNV infection. On testing of the final serum specimen obtained, 14 patients (18%) had positive IgG anti-WNV by EIA and six patients (7%) had indeterminate IgG anti-WNV by EIA, although all were negative by IgM EIA. Four (20%) of the EIA-positive samples were reactive by HI, but all of these were negative by WNV plaque reduction neutralization test; this is consistent with the presence of non-West Nile flavivirus antibody in these sera. Blood specimens obtained throughout the season from EIA- and HI-positive individuals were uniformly negative for WNV-RNA by reverse transcriptasepolymerase chain reaction. Age, sex, hematology and biochemistry findings, hepatitis B or C virus status, immunosuppressive regimen (cyclosporin or tacrolimus) and pretransplant diagnosis of liver disease were similar for EIA-positive and EIA-negative patients. For the 10 patients with a positive IgG EIA maintained on cyclosporin, the cyclosporin level was 129.1+/-28.6 microg/L compared with 85.6+/-36.7 microg/L in 26 patients who were EIA-negative (P=0.002). CONCLUSIONS: False-positive IgG EIA serology for WNV was common in this cohort of liver transplant recipients, and was associated with elevated serum cyclosporin levels.

Evaluation of an automated method for measuring von Willebrand factor activity in clinical samples without ristocetin.

INTRODUCTION: The development of an automated, von Willebrand factor (VWF) activity assay, Innovance(®) VWF Ac (VWF:Ac), which measures VWF binding to the platelet receptor glycoprotein Ibα without ristocetin, led us to evaluate the assay for diagnosing von Willebrand disease (VWD) and monitoring therapy. METHODS: After validating that the assay could be performed on an instrument from a different manufacturer, we compared VWF:Ac to VWF ristocetin cofactor activity (VWF:RCo) findings, including ratios of activity/antigen, for 100 healthy controls and 262 consecutive clinical samples from 217 patients (197 adults, 64 children, n = 1 age unknown) referred for VWF testing. RESULTS: There was excellent correlation (R(2) = 0.96) between VWF:Ac results run at two different sites on two different instruments. VWF:Ac had greater precision and sensitivity to low levels of VWF than the VWF:RCo method. Although there was good correlation between VWF:Ac and VWF:RCo results among healthy controls and patient subjects, VWF:Ac results were undetectable and/or significantly lower than VWF:RCo among patients who had types 2A, 2B, or 2M VWD. Additionally, a higher proportion of patient samples were classified as showing qualitative defects using the VWF:Ac compared with VWF:RCo method. While most samples drawn on VWD therapy had similar VWF levels by VWF:Ac and VWF:RCo, a type 2B VWD subject on replacement had much lower activity estimated by VWF:Ac. CONCLUSION: We conclude that Innovance(®) VWF Ac is suitable for the diagnosis, classification, and monitoring of VWD, and that it has a number of advantages over VWF:RCo method.

Monoclonal B cells detected in autologous PBSC grafts from patients with classical Hodgkin lymphoma: impact on relapse and survival following transplantation.

Autologous peripheral blood stem cell transplantation (PBSCT) for Hodgkin lymphoma (HL) is curative for many patients with relapsed or refractory disease. Relapsing disease, however, remains a major problem. Neoplastic transformation of B-lymphocytes probably underlies the development of classical HL. Whether clonal B cells are critical for disease evolution and response to therapy in HL remains uncertain. We investigated the impact of clonal B cells detected in peripheral blood stem cell (PBSC) collections on the outcome of patients with HL undergoing transplant. Qualitative semi-nested PCR was carried out on genomic DNA from mononuclear cells from PBSCs to determine the presence of clonal immunoglobulin heavy chain (IgH) complementary-determining region 3 (CDR3) gene rearrangements. Clinical factors were assessed for their association with relapse, overall survival (OS) and progression-free survival (PFS). Among 39 patients undergoing PBSCT, 12 grafts (31%) were PCR positive for clonal IgH rearrangements. OS was better in the PCR-negative group (logrank test, P=0.041). The OS at 5 years was 81% in PCR-negative versus 39% in PCR-positive patients; hazard ratio was 3.23 (95% confidence interval: 0.98-10.63). There was a trend towards better PFS (logrank test, P=0.12), estimated as 71% at 5 years in PCR-negative versus 41% in PCR-positive patients. Clonal B-lymphocytes in PBSC collections of patients with HL identify patients at risk of poor outcome. Larger series are needed to confirm our observations. Insight regarding the role of monoclonal B cells may lead to improved therapies.

Contaminating tumour cells in autologous PBSC grafts do not influence survival or relapse following transplant for multiple myeloma or B-cell non-Hodgkin's lymphoma.

Relapsed disease remains a major obstacle following autologous haematopoietic SCT (HSCT) for non-Hodgkin's lymphoma (NHL) and multiple myeloma (MM). Studies regarding the importance of detectable tumour cells in PBSC collections have been inconclusive. Patients undergoing autologous HSCT for NHL and MM between 2001 and 2006 were enrolled (n=158). PBSC grafts were assessed for clonal IgH CDR3 gene rearrangements using qualitative semi-nested PCR. In comparison to patients with PCR-positive PBSC grafts, patients negative for detectable disease had no improvement in overall survival (OS) or PFS for MM (P=0.91 and 0.91) or NHL (P=0.82 and 0.85). Further, no significant difference in OS was observed between patients with PCR-positive compared with PCR-negative PBSC grafts with aggressive NHL histology (P=0.74) or indolent disease (P=0.29). Patients with contaminating tumour cells in autologous PBSCs do not have worsened OS or PFS in MM or NHL. Tumour cells detected by sensitive molecular methods in PBSC collections may be distinct from cells contaminating marrow and appear to have limited utility in identifying patients with MM and B-cell NHL who would benefit from purging strategies.