RESUMO
The aim of this work was to elucidate the immunopathological mechanisms of how helminths may influence the course of a viral infection, using a murine model. Severe virulence, a relevant increase in the virus titres in the lung and a higher mortality rate were observed in Ascaris and Vaccinia virus (VACV) co-infected mice, compared with VACV mono-infected mice. Immunopathological analysis suggested that the ablation of CD8+ T cells, the marked reduction of circulating CD4+ T cells producing IFN-γ, and the robust pulmonary inflammation were associated with the increase of morbidity/mortality in co-infection and subsequently with the negative impact of concomitant pulmonary ascariasis and respiratory VACV infection for the host. On the other hand, when evaluating the impact of the co-infection on the parasitic burden, co-infected mice presented a marked decrease in the total number of migrating Ascaris lung-stage larvae in comparison with Ascaris mono-infection. Taken together, our major findings suggest that Ascaris and VACV co-infection may potentiate the virus-associated pathology by the downmodulation of the VACV-specific immune response. Moreover, this study provides new evidence of how helminth parasites may influence the course of a coincident viral infection.
Assuntos
Ascaríase/virologia , Ascaris/imunologia , Coinfecção/imunologia , Pneumonia/parasitologia , Vaccinia virus/imunologia , Vacínia/etiologia , Animais , Ascaríase/imunologia , Linfócitos T CD8-Positivos/imunologia , Coinfecção/parasitologia , Coinfecção/virologia , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Interferon gama/imunologia , Larva/parasitologia , Pulmão/imunologia , Pulmão/parasitologia , Pulmão/patologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia/imunologia , Pneumonia/virologia , Suínos , Vacínia/imunologia , Vacínia/patologia , Vacínia/virologia , Carga ViralRESUMO
Human respiratory syncytial virus (HRSV) is an important cause of respiratory disease. The majority of studies addressing the importance of virus co-infections to the HRSV-disease have been based on the detection of HRSV by RT-PCR, which may not distinguish current replication from prolonged shedding of remnant RNA from previous HRSV infections. To assess whether co-detections of other common respiratory viruses are associated with increased severity of HRSV illnesses from patients who were shedding viable-HRSV, nasopharyngeal aspirates from children younger than 5 years who sought medical care for respiratory infections in Ribeirão Preto (Brazil) were tested for HRSV by immunofluorescence, RT-PCR and virus isolation in cell culture. All samples with viable-HRSV were tested further by PCR for other respiratory viruses. HRSV-disease severity was assessed by a clinical score scale. A total of 266 samples from 247 children were collected and 111 (42%) were HRSV-positive. HRSV was isolated from 70 (63%), and 52 (74%) of them were positive for at least one additional virus. HRSV-positive diseases were more severe than HRSV-negative ones, but there was no difference in disease severity between patients with viable-HRSV and those HRSV-positives by RT-PCR. Co-detection of other viruses did not correlate with increased disease severity. HRSV isolation in cell culture does not seem to be superior to RT-PCR to distinguish infections associated with HRSV replication in studies of clinical impact of HRSV. A high rate of co-detection of other respiratory viruses was found in samples with viable-HRSV, but this was not associated with more severe HRSV infection.
Assuntos
Coinfecção/virologia , Vírus de RNA/isolamento & purificação , Infecções Respiratórias/virologia , Viroses/virologia , Brasil , Pré-Escolar , Coinfecção/patologia , Feminino , Imunofluorescência , Humanos , Lactente , Recém-Nascido , Masculino , Nasofaringe/virologia , Infecções Respiratórias/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Cultura de Vírus , Viroses/patologiaRESUMO
Se revisaron diversas fuentes bibliográficas sobre la epidemiología de la tuberculosis y el virus de la inmunodeficiencia humana y la coinfección de ambas enfermedades en el mundo. Asimismo, fue analizada la relación entre estos procesos morbosos y se tuvo en cuenta la estrategia global de prevención para reducir la carga de las dos epidemias.
Several literature sources on the epidemiology of tuberculosis and the human inmunodeficiency virus and the co-infection of both diseases in the world were reviewed. Also, the relationship between these disease processes was analyzed and the global strategy of prevention to reduce the load of the two epidemics was kept in mind.
RESUMO
Few studies are available on hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection in populations living in small and medium-sized Brazilian cities. We evaluated the seroprevalence of these viruses in selected individuals from a clinic of infectology, who were referred to the University Regional Hospital of the West Region of state of São Paulo, Brazil. Among a total of 7,021 individuals seen in the clinic following receipt of preliminary ELISA results or having the suggested clinical signs of viral hepatitis or HIV, 1,228 were systematically screened. Isolated or associated HBsAg, HCV and HIV antibodies were found in 44.9 percent of the subjects. Anti-HIV antibodies were found in 24.7 percent of the patients, 20.3 percent of whom had an HIV monoinfection and 4.4 percent of whom were co-infected with hepatitis viruses (HCV: 4 percent; HBV: 0.4 percent). Anti-HCV antibodies were found in 14 percent of the patients and 5.9 percent had anti-HBsAg antibodies. HCV infection affected males more than females (p < 0.05) and individuals > 50-years old had an increased prevalence of anti-HCV compared to HIV (p = 0.0001) or HBV (p = 0.0063). HCV-RNA was detected in 73.5 percent of the samples with a predominance of genotype 1 (72.5 percent). A significant percentage (44.9 percent) of the selected individuals was positive for antibodies against HBV, HCV and/or HIV; these patients would otherwise have remained undiagnosed.
Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Soropositividade para HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Distribuição de Qui-Quadrado , HIV , Soropositividade para HIV/complicações , Hepacivirus/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/complicações , Hepatite C/complicaçõesRESUMO
Bovine papillomavirus (BPV) DNA sequences were detected in different tissues, in addition to epithelium. Cytogenetic abnormalities were observed in blood lymphocytes. The presence of more than one virus in a single tissue is a difficult aspect to evaluate, especially when the DNA sequences are detected in tissues that are not specifically targeted by the virus. BPV and bovine leukemia virus (BLV) are clastogenic, causing chromosome aberrations in peripheral blood lymphocytes. In the present study, we investigated the simultaneous presence of DNA sequences of both viruses and the possibility of vertical transmission and compared the types of chromosome aberrations related to viral action. BPV 1, 2, and 4 DNA sequences were found in three females of the herd and in their offspring. BLV DNA sequences were not detected in their progeny. A newborn calf that was negative for BLV infection showed specific chromosome rearrangements possibly related to the effect of infection with BPV.