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Background: The genus Orthobornavirus comprises RNA viruses infecting humans, mammals, birds and reptiles, where parrot bornavirus 1 to 8 causes fatal neurological and/or gastrointestinal syndromes in psittacines. There is, to the best of our knowledge, no publication describing avian bornaviruses in pet parrots in Sweden. We aimed to identify and to produce epidemiologic knowledge about the etiologic agent associated with a history of severe weight loss and death of a Primolius maracana.Methods and results: The results of histopathology, immunohistochemistry and real-time RT-PCR were compatible with avian bornavirus infection. Sequencing indicated infection by parrot bornavirus 4 (PaBV-4). The genotype reported shared high identity with PaBV-4 identified from pet psittacines and from wild birds in several countries. The N gene and X protein showed genotype clusters formation. P protein revealed to be more conserved within and between species of bornaviruses. Findings suggest horizontal transmission within and between avian orders and species.Conclusion: There seems to be a worldwide trading without biosafety measures, hence, further disease transmission could be avoided. For screening purposes, the P gene is a good candidate as a universal target in molecular diagnostics. Wild birds may be key pieces in the puzzle of bornavirus epidemiology.

Objective Helicobacter pylori infection is the most important risk factor for gastric cancer, but no association with cardia cancer has been recognized. However, a heterogeneous distribution of etiologically distinct types of cardia cancer may contribute to explain conflicting findings between studies in high- and low-risk settings. We aimed to quantify the association between H. pylori infection and gastric cardia cancer through meta-analysis, and to provide an explanation for the expected heterogeneity of results. Methods We systematically reviewed published studies addressing the association between H. pylori infection and gastric cardia cancer (up to June 2009), and extracted relative risk (RR) estimates for the association with cardia and non-cardia cancers. Summary RR estimates and 95% confidence intervals (95% CI) were computed using random-effects models. Subgroup analyses were conducted, namely according to gastric cancer risk settings. Results Thirty-four articles were considered for metaanalysis. For cardia cancer, summary RR was 1.08 (95% CI 0.83‐1.40; I 2 = 52.8%), higher in high-risk (RR = 1.98; 95% CI 1.38‐2.83; I 2 = 18.4%) than in low-risk settings (RR = 0.78; 95% CI 0.63‐0.97; I 2 = 11.6%). For noncardia cancer, RR estimates were similar in high(RR = 3.02; 95% CI 1.92‐4.74; I 2 = 90.7%) and low-risk settings (RR = 2.56; 95% CI 1.99‐3.29; I 2 = 46.6%). These observations were consistent across different inclusion criteria and when accounting for the virulence of the infecting strains. Conclusions In high-risk settings, a positive association between H. pylori infection and gastric cancer was observed both for cardia and non-cardia cancers. The results support the hypothesis of a heterogeneous distribution of etiologically distinct types of cardia cancer.

The coexistence of two aetiologically distinct types of cardia cancer, with distinctive histological characteristics of the neoplastic and nonneoplastic gastric mucosa, may explain the heterogeneous evidence of its association with Helicobacter pylori infection. We compared gastric cardia and noncardia cancers with regard to the frequency of H. pylori infection, the histological characteristics of the nonneoplastic gastric mucosa and the tumour histological type. We evaluated 41 cardia and 339 noncardia cancer cases undergoing gastrectomy, and 380 community controls. H. pylori infection and CagA infection status were assessed by enzyme-linked immunosorbent assay and western blot, respectively. Histological characteristics of the neoplastic and nonneoplastic mucosa were obtained from pathology reports. The association between infection and cancers with different location was quantified in a case-control analysis and cardia and noncardia cancers were further compared. No positive relation was found for H. pylori infection, but CagA-positive strains were associated with an increased risk of noncardia cancer (odds ratio=1.60, 95% confidence interval=1.17-2.18). Twenty-seven (65.8%) cardia cancer cases, predominantly of the intestinal type (66.7%), had nonneoplastic atrophic mucosa and 208 (61.4%) noncardia cancers (56.7% of the intestinal type). Among the cases occurring in nonatrophic patients, the proportion of cancers of the Lauren's intestinal type was 71.4% for cardia and 54.2% for noncardia gastric cancers. Cardia and noncardia cancers were similar with regard to the relation with infection, histological type and condition of the nonneoplastic mucosa, supporting the predominance of cardia cancers determined by H. pylori infection in this European high-risk setting.