We have developed a novel microsphere-based genotyping method for 46 mucosal human papillomavirus (HPV) types. HPV DNA was amplified by PCR using general primers and typed by hybridization to HPV type-specific probes coupled to sortable microspheres based on the Luminex xMAP technology. Hybridization to each probe was specific for each HPV type without cross-hybridization and sensitive enough to allow typing of HPV contained in clinical specimens. The method was validated with direct sequencing and the Roche Linear Array genotyping method.A bout 50 human papillomavirus (HPV) types are associated with infections of the genital, anal, and oropharyngeal mucosae (2,8,10). A few of these are known to be high-risk oncogenic types and the cause of cervical cancer (16), other anogenital cancers, and head and neck malignancies (3,8). Detection of high-risk HPV types collectively is being considered as a screening method for cervical cancer, with the promise of improving the sensitivity and cost-effectiveness of cervical cancer screening programs (6). In recent years, there is also mounting evidence for the utility of type-specific identification of HPV type 16 (HVP16) and HPV18, as these two types are significantly associated with persistent infection and lesion progression, thus conferring a higher risk for cancer than other oncogenic types (15). As HPV16 and -18 account for 70% of the cervical cancers worldwide (2), two HPV vaccines targeting these types have been developed and shown to be highly efficacious in preventing both persistent infection with the types and the associated dysplastic changes in the cervical epithelium that lead to malignant transformation (12,22). Since these vaccines are type specific, it is important to know the distribution of the various HPV types in a population, as well as to have a surveillance system in place to monitor vaccine efficacy over time and any unexpected shifts in the frequency of HPV types not covered by the vaccines. The above highlights the need for and the importance of using type-specific tests for HPV.Numerous HPV typing methods based on a variety of detection platforms have been described in the literature, and some are commercially available (reviewed in reference 19). At the Canadian National Microbiology Laboratory (NML), we have developed a Luminex-based method (NML Luminex assay) to meet our need for sensitive and extensive typing of HPV in the context of epidemiological and molecular surveillance studies at the national level. The assay is based on the xMAP platform (Luminex Corporation, Austin, TX), and it detects 46 mucosal types. In this report, we describe its design and performance.HPV DNA either cloned in plasmids (for validation of the probes) or from clinical cervical cancer specimens (for assay validation) was amplified by a nested PCR method using the PGMY primers for the first step (5, 11) and the GP5ϩ/GP6ϩ primers (7) for the second step. The GP6ϩ primer (Invitrogen, Burlington, ON, Canada) carried a 5= biotin label and phosphorothioate bonds in the f...

This is the first documentation of B19 localization to dermal and glomerular capillary endothelium in HSP. It is important to recognize parvovirus B19-associated adult HSP cases, as the treatment of choice is intravenous gamma globulin in concert with anti-TNFalpha therapy. In contrast immunosuppressive therapy may lead to a persistent and/or worsening disease course.

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The diagnosis of HCV infection has high cost and is time consuming for clinical laboratories. The addition of HCV antigen testing to the battery of laboratory HCV tests and the application of a cost efficient testing algorithm warrants further consideration.

Demographic information and laboratory test results on 136 169 clinical serum specimens submitted to the public health laboratory in Manitoba, Canada, for hepatitis C virus (HCV) testing between January 1995 and December 2003 were analyzed. The difference in the clearance rates of HCV infection, without therapeutic intervention, and the HCV genotypes infecting First Nation and non-First Nation people were studied. The rates of co-infection of HCV-positive individuals with other hepatitis viruses were also compared between the two study groups. The results of the analyses of the data indicated that there was a 4.4-fold increase in the number of specimens tested and a 4.9-fold decrease in HCV antibody (anti-HCV) positive cases during the study period. The proportion of specimens submitted for testing from First Nation individuals was lower than their proportion in the Manitoba population. Our study also indicated that there was a significantly higher proportion of First Nation patients who had self-limiting infection (patients cleared the infection and became HCV RNA negative without anti-HCV treatment) in comparison to non-First Nation patients. The proportion of First Nation females who had self-limiting infection was significantly higher than non-First Nation females. HCV genotype 1 infection represented more than 60% of HCV infection in Manitoba. The rate of individuals positive for the hepatitis A virus antibody in the HCV-positive population was higher among First Nation than non-First Nation individuals. On the other hand, there were more HCV-infected First Nation patients than non-First Nation patients who were not immune to the hepatitis B virus. The data indicate that fewer First Nation patients seek anti-HCV therapy in comparison to non-First Nation. In conclusion, the differences in the rates of HCV self-limiting infection between First Nation and non-First Nation individuals in Manitoba may reflect the genetic differences between the two cohorts, which may consequently affect the immune response to the HCV infection.

The prevalence of hepatitis B among the Canadian Inuit population is 4%. This study will use a mathematical model to compare the roles of vaccination and therapy to predict future prevalence and incidence among the Canadian Inuit population for the next 50 years. We applied a mathematical model developed by Medley et al. (Nat Med 7(5):619-624, 2001), combined with data on hepatitis B incidence, prevalence, and vaccination coverage, to predict trends of hepatitis B virus (HBV) among the Inuit population over the next 50 years. The current estimated prevalence of HBV is 6.04% and the incidence is 3.4/100,000 persons among Canadian Inuit. If HBV vaccination coverage levels of 47.2% remain unchanged, the prevalence of HBV will decrease to 1.91% and the incidence will decrease to 0.81/100,000 persons by 2058. If vaccination coverage levels are increased to 57.2%, the prevalence and incidence of HBV will decrease to 1.74% and 0.63/100,000 persons, respectively. If we increase both immunization and therapy by 10%, this will produce the greatest reduction in prevalence and incidence, to 1.56% and 0.54/100,000 persons, respectively. The combination of immunization and treatment programs seems to have the best result in decreasing the prevalence and incidence of HBV among the Inuit population.

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The living conditions of many aboriginal communities in Canada may place their residents at risk for H. pylori infection. Our aims were to determine: (1) the seroprevalence of H. pylori in a traditional Indian community, (2) the clinical relevance of H. pylori infection in this population, and (3) if H. pylori could be identified by polymerase chain reaction from the local water. A demographic questionnaire was administered, and blood was collected from subjects in an Indian community in northwestern Manitoba. The serum was analyzed by ELISA for IgG to H. pylori and to CagA. ABO and Lewis antigens were tested. Age-adjusted incidence of gastric cancer and of hospitalizations associated with diagnoses of peptic ulcer were determined for the Indian and non-Indian Manitoba population in the years 1989-1993. Nested PCR was performed on lake water using H. pylori-specific primers and the amplicons probed with an internal Dig-labeled probe. Three hundred six (59%) of approximately 518 individuals who were resident in the community at the time of the study were enrolled. The ELISA for H. pylori was positive in 291 (95%). There was no association between H. pylori seropositivity and age, sex, gastrointestinal complaints, medications, housing characteristics, and ABO or Lewis antigen status. CagA was positive in 84.5% of infected subjects. The average annual age-adjusted incidence of hospitalizations associated with diagnoses of peptic ulcer disease in Manitoba was higher for treaty-status Indians (394.3/100,000) than for non-Indians (203.8/100,000), but gastric cancer rates were similar (11.2/100,000 vs 11.6/100,000). No H. pylori DNA was detected in the lake water. In conclusion, the seroprevalence of CagA-positive H. pylori is high in this representative Manitoban Indian community. This may be associated with an increased risk for peptic ulcer disease but is not associated with an increased risk for gastric cancer.