Detection and partial characterization of an isolate of Groundnut ringspot virus in Solanum sessiliflorum

The cubiu (Solanum sessiliflorum) fruit, originating in the Amazon basin, is commonly used in that region for food, medicine, and cosmetics. In an experimental culture of cubiu, in order to evaluate its adaptation to conditions in the Northern region of the state of Rio de Janeiro, it was observed plants with mosaic symptoms. A cubiu plant was collected and analyzed to identify the etiological agent. After mechanical passage through a local lesion host, a host range test was performed. The virus induced chlorotic local lesions in Chenopodium quinoa, necrotic local lesions in Gomphrena globosa, mosaic in S. sessiliflorum, leaf and stem necrosis in tomato (Lycopersicon esculentum) 'Rutgers', mosaic and leaf distortion in Datura stramonium and Physalis floridana, and necrotic local lesions followed by systemic necrosis and plant death in four Nicotiana species. Electron microscopic observations of ultra thin sections from infected cubiu leaves showed the presence of spheroidal, membrane-bound particles typical of tospovirus species. Analysis of the nucleocapsid protein from concentrated virus particles indicated the presence of a 28 kDa protein. RT-PCR was performed after total RNA extraction from infected IPA-6 tomato leaves. A fragment of approximately 0,8 kbp corresponding to the N gene was amplified, cloned and sequenced. The N protein from the cubiu isolate was 95% homologous to the Groundnut ringspot virus (GRSV) protein, and no more than 85% homologous to those from Zucchini lethal chlorosis virus (ZLCV) and Chrysanthemun stem necrosis virus (CSNV), Tomato spotted wilt virus (TSWV), and Tomato chlorotic spot virus (TCSV). This is the first report of the occurrence of GRSV (or any other plant virus) in cubiu.

Tomato chlorotic spot virus in hydroponically-grown lettuce in São Paulo State, Brazil

In the regions of Campinas and Sumaré, São Paulo, Brazil, hidroponically grown crops of Lettuce (Lactuca sativa) cv. Verônica, which showed virus-like symptoms were examined by electron microscope, biological, serological and molecular tests. Pleomorphic, enveloped particles (80-100 nm in diameter) were always detected in these samples. Experimentally inoculated host plants, including lettuce, reacted with tospoviruses-induced symptoms. Some differences were observed in Gomphrena globosa, which reacted by showing local lesions and systemic mosaic. Two isolates of Tomato chlorotic spot virus (TCSV) were identified by DAS-ELISA and by RT-PCR. The sequencing and alignment of the RT-PCR coat protein amplified fragments have indicated a high degree of homology with the TCSV sequences stored in the GenBank. This is the first report of losses due to a virus from the genus Tospovirus in commercial hydroponic lettuce crops in Brazil. Further epidemiological studies are needed for better understanding the spread of the virus in hydroponic crops, since Tomato spotted wilt virus (TSWV) is reported to spread through the nutritive solution.

Inhibition of Mayaro virus replication by prostaglandin A1 and B2 in Vero cells

The effect of prostaglandins (PGA1 and PGB2) on the replication of Mayaro virus was studied in Vero cells. PGA1 and PGB2 antiviral activity was found to be dose-dependent. However, while 10 µg/ml PGB2 inhibited virus yield by 60%, at the same dose PGA1 suppressed virus replication by more than 90%. SDS-PAGE analysis of [35S]-methionine-labelled proteins showed that PGA1 did not alter cellular protein synthesis. In infected cells, PGA1 slightly inhibited the synthesis of protein C, while drastically inhibiting the synthesis of glycoproteins E1 and E2.

Hepatitis B virus genotype E detected in Brazil in an African patient who is a frequent traveler

Genotype E of hepatitis B virus (HBV) has not been described in Brazil and is found mainly in Africa. Genotype A is the most prevalent in Brazil, and genotypes B, C, D, and F have already been reported. We report here an HBV genotype E-infected patient and some characterization of surface (S) protein, DNA polymerase (P) and precore/core (preC/C) coding regions based on the viral genome. The patient is a 31-year-old black man with chronic hepatitis B who was born and raised in Angola. He has been followed by a hepatologist in São Paulo, Brazil, since November 2003, and he is a frequent traveler to Latin America, Africa, and Europe. In 2003, he was diagnosed with HBV infection and started treatment with lamivudine with the later addition of adefovir dipivoxil. No known risk factor was identified. Serologically, he is HBsAg and anti-HBe positive, but HBeAg and anti-HBs negative. DNA sequence analysis of the S/P region confirmed that this patient is infected with genotype E, subtype ayw4. The preC/C region showed G1896A and G1899A mutations but no mutations in the basal core promoter. Nucleotide substitutions common in genotype E were also observed (C1772, T1858 and A1757). Although this is not an autochthonous case and there is no evidence of further spread, the description of this case in Brazil highlights the current risk of viral genotypes spreading with unprecedented speed due to constant travel around the world.

Hepatitis B virus subgenotype C2- and B2-associated mutation patterns may be responsible for liver cirrhosis and hepatocellular carcinoma, respectively

The objective of this study was to examine hepatitis B virus (HBV) subgenotypes and mutations in enhancer II, basal core promoter, and precore regions of HBV in relation to risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in Southeast China. A case-control study was performed, including chronic hepatitis B (CHB; n=125), LC (n=120), and HCC (n=136). HBV was genotyped by multiplex polymerase chain reaction and subgenotyped by restriction fragment length polymorphism. HBV mutations were measured by DNA sequencing. HBV genotype C (68.2%) predominated and genotype B (30.2%) was the second most common. Of these, C2 (67.5%) was the most prevalent subgenotype, and B2 (30.2%) ranked second. Thirteen mutations with a frequency >5% were detected. Seven mutation patterns (C1653T, G1719T, G1730C, T1753C, A1762T, G1764A, and G1799C) were associated with C2, and four patterns (C1810T, A1846T, G1862T, and G1896A) were associated with B2. Six patterns (C1653T, G1730C, T1753C, A1762T, G1764A, and G1799C) were obviously associated with LC, and 10 patterns (C1653T, G1730C, T1753C, A1762T, G1764A, G1799C, C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with CHB. Four patterns (C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with LC. Multivariate regression analyses showed that HBV subgenotype C2 and C2-associated mutation patterns (C1653T, T1753C, A1762T, and G1764A) were independent risk factors for LC when CHB was the control, and that B2-associated mutation patterns (C1810T, A1846T, G1862T, and G1896A) were independent risk factors for HCC when LC was the control.

The measurement by serological means of the impact of the Hong Kong/68 influenza virus on a population

In order to obtain evidence on the size of the impact of the Hong Kong/68 variant of influenza A2 virus on the population of São Paulo, Brazil, serum samples taken in 1967 before this variant appeared and during successive years after it appeared were examined for their antibody content. Haemagglutination-inhibition tests performed on a total of 2726 serum samples from adults showed a sharp decrease in 1969 of the proportion of sera without antibody to the Hong Kong/68 variant and a corresponding mercase in the proportion with high titres. It was concluded that about three-quarters of the adult population became infected at some time after the variant appeared, the majority in the first year of prevalence.

Dados preliminares sobre partículas semelhantes a virus em células de triatomíneos

Nos tubos de Malpighi de Triatoma infestans Klug e de Panstrongylus megistus Burmeister foram encontradas estruturas víricas distribuídas no citoplasma, no interior de citolissomos ou outros tipos de glóbulos, formando às vezes arranjos para cristalinos envolvidos por membrana, e entre plasmalemas de células contíguas. Outros tecidos dos mesmos insetos apresentam arranjos paracristalinos desses virus. A análise citoquímica ao nível da microscopia eletrônica indica serem estes virus compostos de RNP. Não são encontradas alterações morfológicas drásticas nos tecidos infectados. Admite-se que tais virus tenham sido ingeridos durante uma alimentação de sangue infectado de ave.

Soro-epidemiologia do virus de Epstein-Barr (VEB)

É feita revisão dos estudos soro-epidemiológicos do vírus de Epstein-Barr (vírus EB), mostrando a ubicuidade deste vírus, bem como sua relação com doenças malígnas e não malígnas do homem. O desenvolvimento de novas técnicas laboratoriais e o acúmulo, nos últimos 10 anos, de grande número de estudos soro-epidemiológicos, levaram à conclusão de que, além da associação etiológica com a mononucleose infecciosa, torna-se cada vez mais evidente a ligação do vírus EB com o linfoma de Burkitt e com o carcinoma do nasofaringe. Estas observações, além de sua extraordinária importância intrínseca, tem sido de grande utilidade para a melhor compreensão dos possíveis mecanismos e efeitos das infecções virais no homem.

Vector competence experiments with Rocio virus and three mosquito species from the epidemic zone in Brazil

First-generation progeny of field-collected Psorophora ferox, Aedes scapularis, and Aedes serratus from the Rocio encephalitis epidemic zone in S.Paulo State, Brazil, were tested for vector competency in the laboratory. Psorophora ferox and Ae. scapularis are susceptible to per os infection with Rocio virus and can transmit the virus by bite following a suitable incubation period. Oral ID50S for the two species (10(4.1) and 10(4.3) Vero cell plaque forming units, respectively) did not differ significantly. Infection rates in Ae. serratus never exceeded 36%, and, consequently, an ID50 could not be calculated for this species. It is unlikely that Ae. serratus is an epidemiologically important vector of Rocio virus. The utility of an in vitro feeding technique for demonstrating virus transmission by infected mosquitoes and difficulties encountered in working with uncolonized progeny of field-collected mosquitoes are discussed.

Peroral susceptibility of Aedes albifasciatus and Culex pipiens complex mosquitoes (Diptera: Culicidae) from Argentina to western equine encephalitis virus

The transmission cycle of western equine encephalitis (WEE) virus in South America is unknown. A WEE virus strain was isolated from Aedes albifasciatus in Argentina during the WEE epizootic of 1982-83. Also, Culex pipiens from Argentina was reported to be able to transmit WEE virus experimentally, but other results indicate that Cx. pipiens from the USA is refractory to this virus. We determined the susceptibility of Argentina strains of Ae. albifasciatus and Culex pipiens complex mosquites to infection by WEE virus by the oral route. Adult females were fed on chicks infected with a WEE virus strain isolated in Cordoba Province, Argentina, or were fed on a blood/virus suspension. Each mosquito ingested between 10(1.6) to 10(6.4) vero cell plaque-forming units of virus. Each of 28 Ae. albifasciatus was positive for virus from the fourth day postfeeding, and there was evidence for virus replication. In contrast, 0/44 Cx. p. quinquefasciatus and only 1/15 Cx. p. pipiens was positive. Aedes albifasciatus is susceptible to infection by WEE virus and should be considered a potential vector of this virus in Argentina. Both subspecies of Cx. pipiens are refractory to peroral infection by WEE virus and probably do not play a role in the WEE virus cycle in Argentina.

A case-control study on the association of hepatitis B virus infection and hepatocellular carcinoma in Northeast Brazil

Hepatitis B virus (HBV) serological markers were investigated in 40 incident cases of hepatocellular carcinoma (HCC) and in two age and sex matched control groups, comprising 40 patients with other cancers and 80 healthy individuals, resident in Bahia, Brazil. Serologic tests were done by radioimmunoassay. The study observed high proportion of seropositivity to HBsAg (42.5%) and of those presenting HBsAg or antiHBc (65.0%) among HCC cases, higher in men than women and in those aged 17 to 30 years old. HBsAg seropositivity among HCC patients was greater than in the control group with other cancers (7.5%) and in healthy controls (2.5%), corresponding to odds ratio estimates of 15.0 (95% CI 3.29, 68.30) and 33.0 (95% CI 9.13, 119.28), both statistically significant. HBeAg was not observed and antiHBe was present in 41.2% of cases, suggesting the absence of viral replication, possibly with viral DNA intergration into the hepatocyte genome. The presence of cirrhosis was associated with HBsAg seropositivity among HCC cases. A history of chronic alcoholism is shown to be more frequently related to those cases with cirrhosis. This study highlights the relevant association between HCC and HBV in Northeast Brazil, particularly for young individuals, and the high risk of development of HCC for HBsAg carriers.

RC-IAL cell line: sensitivity of rubella virus grow

OBJECTIVE: The rapid growth of the rubella virus in RC-IAL² with development of cytopathic effect, in response to rubella virus infection, is described. For purposes of comparison, the rubella virus RA-27/3 strain was titered simultaneously in the RC-IAL, Vero, SIRC and RK13 cell lines. METHODS: Rubella virus RA-27/3 strain are inoculated in the RC-IAL cell line (rabbit Kidney, Institute Adolfo Lutz). Plates containing 1.5x10(5) cells/ml of RC-IAL line were inoculated with 0.1ml s RA-27/3 strain virus containing 1x 10(4)TCID50/0.1ml. A 25% cytopathic effect was observed after 48 hours and 100% after 96 hours. The results obtained were compared to those observed with the SIRC, Vero and RK13 cell lines. Rubella virus was detected by immunohistochemistry. RESULTS: With the results, it was possible to conclude that the RC-IAL cell line is a very good substrate for culturing rubella virus. The cells inoculated with rubella virus were examined by phase contrast microscopy and showed the characteristic rounded, bipolar and multipolar cells. The CPE in RC-IAL was observed in the first 48 hours and the curve of the increased infectivity was practically the same as observed in other cell lines. CONCLUSIONS: These findings are important since this is one the few cell lines described in the literature with a cytopathic effect. So it can be used for antigen preparation and serological testing for the diagnosis of specific rubella antibodies.

Aedes albopictus may not be vector of dengue virus in human epidemics in Brazil

Over 60,500 dengue cases were reported in the state of Espírito Santo (ES), Brazil, between 1995 and 1998. The study's purpose was to identify whether Aedes albopictus was transmitting the dengue virus during an epidemic in the locality of Vila Bethânia (Viana County),Vitória, ES. From April 3 to 9, 1998, blood and serum samples were collected daily for virus isolation and serological testing. Four autochthonous cases were confirmed through DEN 1 virus isolation and two autochthonous cases through MAC ELISA testing. Of 37 Ae. aegypti and 200 Ae. albopictus adult mosquitoes collected and inoculated, DEN1 virus was isolated only from a pool of two Ae. aegypti female mosquitoes. The study results suggest that Ae. albopictus still cannot be considered an inter-human vector in dengue epidemics in Brazil.

Prevalence of hepatitis C virus in Brazil’s inmate population: a systematic review

OBJECTIVE To estimate the prevalence of hepatitis C virus infection in Brazil’s inmate population.METHODS Systematic review on hepatitis C virus infection in the inmate population. Brazilian studies published from January 1, 1989 to February 20, 2014 were evaluated. The methodological quality of the studies was assessed using a scale of 0 to 8 points.RESULTS Eleven eligible studies were analyzed and provided data on hepatitis C virus infection among 4,375 inmates from seven states of Brazil, with a mean quality classification of 7.4. The overall hepatitis C virus prevalence among Brazilian inmates was 13.6% (ranging from 1.0% to 41.0%, depending on the study). The chances of inmates being seropositive for hepatitis C virus in the states of Minas Gerais (MG), Sergipe (SE), Mato Grosso do Sul (MS), Rio Grande do Sul (RS), Goiás (GO) and Espirito Santo (ES) were 84.0% (95%CI 0.06;0.45), 92.0% (95%CI 0.04;0.13), 88.0% (95%CI 0.09;0.18), 74.0% (95%CI 0.16;0.42), 84.0% (95%CI 0.08;0.31) and 89.0% (95%CI 0.01;0.05) respectively, lower than that observed in the Sao Paulo state (seroprevalence of 29.3%). The four studies conducted in the city of Sao Paulo revealed a lower prevalence in more recent studies compared to older ones.CONCLUSIONS The highest prevalence of hepatitis C virus infection in Brazil’s inmate population was found in Sao Paulo, which may reflect the urban diversity of the country. Despite Brazilian studies having good methodological quality to evaluate the prevalence of the hepatitis C virus, they are scarce and lack data on risk factors associated with this infection, which could support decisions on prevention and implementation of public health policies for Brazilian prisons.

Prevalence of antibody to hepatitis B virus in an urban population of northeast Brazil

A sample of 1,288 inhabitants of Salvador, Bahia, Brazil, were submitted to the determination of anti-HBs using radioimmunoassay procedure, and analysed according to age, sex and income. Overall prevalence of anti-HBs was 11,8%. ranging from 6,7% among children aged less than three years old to 26,1% among those aged 30 years and older. Males presented prevalence of anti-HBs similar to female individuals, and those with a higher income showed frequencies of anti-HBs greater than those with a lower income level. The following conclusions were drawn: The high prevalence of anti-HBs observed among children suggests early contact with hepatitis B virus, possibly due to vertical transmission and intrafamiliar dissemination of the disease; the frequency of anti-HBs increases with age; the lower prevalence of anti-HBs among those with low income suggests that this group may present higher prevalence of carriers of the hepatitis B virus surface antigen.