Although cases of lichen planus (LP) associated with hepatitis C virus (HCV) infection have been described, the association between the two diseases has not been established because the geographic origin of patients could be an important factor in HCV prevalence in patients with LP. The serum samples of 78 consecutive patients with cutaneous and/or mucous LP and 82 control patients were analysed for the presence of antibodies to HCV by enzyme-immunoassay and for the presence of antigens of HCV by two-stage polymerase chain reaction (PCR). The clinical features of patients with LP associated with HCV infection were compared with patients with LP without HCV infection. Sixteen of the 78 (20%) patients had anti-HCV antibodies. In 13 of these 16 cases (81%), HCV-RNA was detected by PCR in serum samples. In the 82 control patients, anti-HCV antibodies was observed in two (2.4%) patients. We have found a statistically significant association (P < 0.05) between erosive LP and HCV infection. We conclude that the high prevalence of HCV-RNA in patients with LP provides some evidence for the role of HCV in the pathogenesis of LP. Our results suggest an association between erosive LP and HCV infection.

Human pegivirus-1 (HPgV-1) is a member of the Flaviviridae family and the Pegivirus genus. Despite having been discovered 25 years ago, there is still much to know regarding HPgV-1 clinical impact, as this virus is currently not associated with any pathology. Yet, HPgV-1 prevalence and molecular characterization are still unknown in many countries, including Portugal. To fill in this knowledge gap, this study aimed to determine the occurrence and molecular characterization of HPgV-1 in a group of healthy blood donors from the north of Portugal. Blood samples from 465 Portuguese blood donors were collected from a major Hospital Center in the north of Portugal. RNA was extracted and an initial nested RT-PCR was performed targeting the conserved 5′-untranslated region region of the HPgV-1 genome. A second nested RT-PCR targeting the E2 region was performed for genotyping. Only one sample tested positive for HPgV-1 RNA, resulting in a prevalence of approximately 0.22%. Phylogenetic analyses confirmed the characterization as genotype 2, the most prevalent in Europe.

A survey was performed from 1999 to 2002 in the main citrus regions (13,551 ha) of Chile to estimate the Citrus tristeza virus (CTV) incidence. One thousand three hundred and twenty-three commercial citrus orchards were visited and 90,267 trees were observed for symptoms, sampled and analyzed by DAS-ELISA and tissue print-ELISA using 3DF1 and 3CA5 monoclonal antibodies. In this survey stem pitting symptoms were detected on CTV-infected grapefruit and Mexican lime trees grown in small orchards located in the Pica Oasis where the CTV incidence was 17.2%. In central Chile, where the main commercial orchards are located, CTV incidence ranged from zero to 0.37%. The average incidence of CTV in Chile was estimated at 0.38%. From this survey 100 CTV isolates representative of different hosts and geographical origins were selected and inoculated on sweet orange and/or Mexican lime and conserved in a collection kept in screenhouse facilities. The isolates in the collection were biologically and serologically characterized. Severe CTV isolates were found in Region I (where Pica Oasis is located). Serological characterization was done by DASI-ELISA using 12 different monoclonal antibodies, including MCA 13. Eight different serogroups were detected, two of which included CTV isolates which yielded a positive MCA 13 reaction.