Respiratory syncytial virus (RSV) bronchiolitis: comparative study of RSV groups A and B infected children

The grouping characteristics of 29 respiratory syncitial virus (RSV) present in nasopharyngeal cells collectedfrom hospitalized children with bronchiolitis during the 1990RSVseason in Porto Alegre, RS, were analysed. Twenty-two were grouped as belonging to group A and 7 to group B. Cyanosis, oxigen therapy, cough, lenght of hospitalization and atelectasis were observed to be more frequently found within group B infected children. Other clinical signs and symptoms were similarly found in both groups.

Acute exacerbation in chronic hepatitis B virus infection

A case of an acute exacerbation of liver injury in a chronic HBV infected young male is reported. The correlation between the severe symptomatic hepatitis is done with the histopathologic findings of extense areas of bridging necrosis on the Iwer biopsy. The serological pattern for markers of HBV (HBsAg +, anti HBs g -, HBeAg -, anti HBe +, anti HBcIgG + and IgM -) confirm a chronic infection, ana the authors propose that the episode of severe hepatitis relates to the recent spontaneous seroconvertion of HBe Ag to anti HBe. Other causes of hepatitis were excluded, and the control liver biopsy (6 months later) showed normalization of hepatic architecture and absence of markers of viral replication in tissue and serum. A review of literature is done in an attempt to elucidate the diagnostic possibilities in this case, with emphasis on new immunoassays useful in differentiating between acute hepatitis B and acute exacerbation of a chronic hepatitis by the same virus.

Soroepidemiologia para o virus da hepatite B (VHB) em gestantes/parturientes e sua transmissão para recém-nascidos em Goiânia, GO

Foram coletadas, entre março de 1990 e julho de 1992, 1459 amostras sanguíneas de mulheres gestantes/parturientes na cidade de Goiânia-GO, objetivando detecção da infecção pelo vírus da hepatite B (VHB), através dos marcadores sorológicos AgHBs e anti-HBs. O percentual depositividade encontrado, pelo teste imunoenzimãtico, foi de 7,5%, sendo 0,5%para AgHBs e 7,0%para anti-HBs. A análise efetuada, considerando a faixa etária, mostra que 7 de 8 mulheres AgHBs-positivas pertenciam à faixa etária de até 30 anos, situação semelhante em relação ao anti-HBs(83/101). Das 8 mulheres positivas, 4 tiveram seus recém-nascidos submetidos a tratamento profilático com vacina (Engerix B) e imunoglobulina humana anti-hepatite B (HBIG). Além disso, 3 dessas crianças foram analisadas sorologicamente, sendo que uma era AgHBs-positiva ao nascimento. Doença sexualmente transmissível e transfusão sanguínea foram fatores de risco que coirelacionaram significantemente com a infecção. Esses resultados parece-nos reforçar a indicação de triagem à infecção pelo vírus da hepatite B no período pré-natal, assim como a adoção de medidas imunoprofiláticas nas crianças nascidas de mães positivas.

Epidemiological aspects of the Brazilian spotted fever: seasonal activity of ticks collected in an endemic area in São Paulo, Brazil

Ticks were collected from vegetation and animals at monthly intervals during one year (1993-1994) in an endemic area of Brazilian spotted fever in the County of Pedreira, State of São Paulo. Six species of ticks were identified Amblyomma cajennense, Amblyomma cooperi, Amblyomma triste, Anocentor nitens, Rhipicephalus sanguineus and Boophilus microplus. Only the first species was sufficiently numerous to permit a quantitative study with seasonal activity, although the distribution and source of capture of other species were observed and are reported. This information is correlated with the epidemiology of tick-borne rickettsiosis.

Effect of a booster-dose of rabies vaccine on the duration of virus neutralizing antibody titers in bovines

Humoral immune response using inactivated rabies vaccine was studied in 35 nelore cross-bred bovines of western region of São Paulo state. Ninety days after vaccination, 13 (92.8%) animals presented titers 30.5IU/ml, through mouse neutralization test. After 180 days, 9 (64.3%) sera showed titers 30.5IU/ml, after 270 days, only one (7.1%) showed a titer of 0.51IU/ml, and after 360 days, all animals showed titers < 0.5IU/ml. Group of animals receiving booster dose 30 days after vaccination presented, two months after, all with titers > 0.5IU/ml. At 180 days, 17 (80.9%) sera presented titers > 0.5IU/ml; at 270 days, 15 (71.4%), with titers 30.5IU/ml and at 360 days, 4 (19.0%), with titers 30.5IU/ml. Booster-dose ensured high levels of neutralizing antibodies for at least three months, and 240 days after revaccination, 71.4% of animals were found with titers 30.5IU/ml.

Hepatitis B virus surface antigen (HBsAg) and antibody (anti-HBs) forming immune complexes in fulminant hepatitis

This paper reports an unusual pattern of serological HBV markers and the presence of HBsAg/anti-HBs immune complexes in serum samples from two patients with fulminant hepatitis from the Brazilian Western Amazon Basin. The diagnosis was made by both serologic tests and demonstration of antigen/antibody complexes by transmission electron microscopy. Concurrent Delta virus superinfection is also discussed.

Prevalence of HIV-1/2, HTLV-I/II, hepatitis B virus (HBV), hepatitis C virus (HCV), Treponema pallidum and Trypanosoma cruzi among prison inmates at Manhuaçu, Minas Gerais State, Brazil

The purpose of this study was to determine the seroprevalence of human immunodeficiency virus (HIV-1/2), human T-cell lymphotropic virus (HTLV-I/II), hepatitis B virus (HBV), hepatitis C virus (HCV), Treponema pallidum and Trypanosoma cruzi among 63 male prisoners in Manhuaçu, Minas Gerais, Brazil and to compare this with data from eligible blood donors. The positive results were as follows: 11/63 (17.5%) for HBV, 5/63 (7.4%) for syphilis, 4/63 (6.3%) for HCV, 3/63 (4.8%) for Chagas' disease, 2/63 (3.2%) for HIV-1/2 and 1/63 (1.6%) for HTLV-I/II. The seroprevalence in prisoners was higher than among blood donors, mainly for antibodies to HIV-1/2, HCV and HBV. This is probably due to low social economic level, illiteracy, higher proportion with a prior history of intravenous drug use and/or unsafe sexual behavior. Therefore, these prisoners constitute a high risk group and routine screening and counseling are recommended.

First isolation of dengue 1 virus from Aedes aegypti in Federal District, Brazil

Dengue is present in the Federal District since 1991 and virological studies of the vector began in 1998. Two strains of DEN1 were isolated from 9 pools of female Aedes aegypti (78 mosq.), collected in April in Gama county, where the Breteau index was 5.4, and 32 autochtonous human cases were notified.

Brazilian spotted fever: description of a fatal clinical case in the State of Rio de Janeiro

We describe a case of Brazilian spotted fever in a previously healthy young woman who died with petechial rash associated to acute renal and respiratory insufficiency 12 days following fever, headache, myalgia, and diarrhea. Serologic test in a serum sample, using an immunofluorescence assay, revealed reactive IgM/IgG.

Spotted fever rickettsiosis in Coronel Fabriciano, Minas Gerais State

We report cases of spotted fever rickettsiosis in Coronel Fabriciano Municipality of Minas Gerais State, Brazil. The cases occurred in May and June of 2000. During this period there were two deaths among children from an area named Pedreira in a periurban area of this municipality. In a boy who died with clinical manifestations of Brazilian spotted fever, a necropsy revealed the presence of a spotted fever group Rickettsia. The serological results confirm the difficulty in the differential diagnosis of patients with symptoms of rickettsial diseases.

The usefulness of Umelosa hepatitis C vírus qualitative kit as supplemental test for confirmation of hepatitis C virus infection

Forty voluntary blood donors from two different blood banks in Havana, Cuba, who were repeatedly reactive on the routine screening of antibodies to hepatitis C virus, by Umelisa HCV test, were analyzed for the presence of HCV RNA using a nested PCR assay of the HCV 5' untranslated region, Umelosa HCV qualitative. Sera from 45 patients of a specialized gastroenterology consultation, positive to Umelisa HCV, were also assayed with the Umelosa HCV qualitative, to establish their condition related to the presence of HCV RNA previously to the indication of a treatment or after three, six or twelve months of antiviral therapy. Serum HCV-RNA was detected in 21/40 (52.5%) donors who had repeatedly positive ELISA results, confirming the HCV infection for them. In specialized consultation HCV-RNA was detected by PCR analysis in 30/45 (66%) analyzed sera.

Prevalence of Epstein-Barr virus antibodies in healthy children and adolescents in Vitória, State of Espírito Santo, Brazil

The prevalence and age distribution of Epstein-Barr virus infection varies in different populations and there is little information about the epidemiology of this infection in Brazil. We studied the prevalence of EBV antibodies in a sample of 283 children and adolescents between 1 and 21 years old. The sample was taken from two neighborhoods in Vitória (capital city of Espirito Santo, Brazil). The São Pedro (SP) neighborhood represented an area with lower socioeconomic status and the Praias (P) neighborhood represented an area with higher SES. Anti-VCA (Virus Capsid Antigen) antibodies were detected by ELISA and anti-EBNA (Epstein-Barr Nuclear Antigen) antibodies were detected by an anti-complement immunofluorescence method, both using commercial kits. The results showed an overall prevalence rates of anti-VCA and anti-EBNA of 71% and 54% respectively. The prevalence for both anti-EBV antibodies was higher and probably the infection occurred earlier in the SP neighborhood. Among the various socioeconomic factors studied only low family income and maternal education level were significantly correlated with a higher frequency of positive serology for anti-VCA. These results demonstrate that there is a high prevalence of EBV antibodies in children and adolescents living in Vitória, that occurs more frequently at a younger age in children from families with low socioeconomic status. In addition, the results demonstrate an intermediate age distribution pattern between those reported in developed and underdeveloped countries.