Prevalence and clinical implications of low-risk human papillomavirus among patients with recurrent respiratory papillomatosis in Rio de Janeiro, Brazil.

OBJECTIVE: The aim of this study was to investigate the presence of human papillomavirus (HPV) in biopsy specimens from juvenile and adult patients with histopathological diagnosis of recurrent respiratory papillomatosis (RRP) treated in two public hospitals in Rio de Janeiro, Brazil. METHODS: We performed the detection and genotyping of HPV by PCR technique for the types 6, 11, 16, and 18 in biopsy specimens from 41 RRP patients. RESULTS: The juvenile onset RRP (JoRRP) corresponded to 61% and the adult onset RRP (AoRRP) corresponded to 39% of the study group. Prevalence of males was observed in both the adult (81.3%) and the juvenile (56%) groups. Lesions in the larynx were more frequent in the glottis (46%). Genotyping analysis only revealed patients with HPV-6 (34.1%), HPV-11(17.1%), and co-infection HPV-6 and -11 (48.8%). RRP severity was significantly associated with the JoRRP (p<0.001), with extralaryngeal disease and more surgeries. However, no significant association between RRP severity and HPV types was found. One co-infected patient in the JoRRP died due to the evolution of the disease with lung involvement. CONCLUSION: These results show the strong association of HPV-6 and/or HPV-11 types with RRP and could complement the diagnosis, prognosis, and therapies for these patients. In addition, the HPV vaccination should be encouraged to prevent the disease.

Avian coronavirus isolated from a pigeon sample induced clinical disease, tracheal ciliostasis, and a high humoral response in day-old chicks.

The detection of avian coronaviruses (AvCoV) in wild birds and the emergence of new AvCoV have increased in the past few years. In the present study, the pathogenicity of three AvCoV isolates was investigated in day-old chicks. One AvCoV isolated from a pigeon, which clustered with the Massachusetts vaccine serotype, and two AvCoV isolated from chickens, which grouped with a Brazilian genotype lineage, were used. Clinical signs, gross lesions, histopathological changes, ciliary activity, viral RNA detection, and serology were evaluated during 42 days post infection. All AvCoV isolates induced clinical signs, gross lesions in the trachea, moderate histopathological changes in the respiratory tract, and mild changes in other tissues. AvCoV isolated from the pigeon sample caused complete tracheal ciliostasis over a longer time span. Specific viral RNA was detected in all tissues, but the highest RNA loads were detected in the digestive tract (cloacal swabs and ileum). The highest antibody levels were also detected in the group infected with an isolate from the pigeon. These results confirm the pathogenicity of Brazilian variants, which can cause disease and induce gross lesions and histopathological changes in chickens. Our results suggest that non-Galliformes birds can also play a role in the ecology of AvCoV.