High prevalence of hepatitis E virus antibodies in Sao Paulo, Southeastern Brazil: analysis of a group of blood donors representative of the general population

Abstract Brazil is a non-endemic country for hepatitis E virus (HEV) infection with seroprevalence from 1% to 4% in blood donors and the general population. However, data on seroprevalence of HEV in the country are still limited. This study evaluated the prevalence of past or present HEV infection in a group of blood donors representative of the general population of the city of Sao Paulo, Southeastern Brazil. Serum samples from 500 blood donors were tested from July to September 2014 by serological and molecular methods. Anti-HEV IgG antibodies were detected in 49 (9.8%) subjects and categorized age groups revealed an age-dependent increase of HEV seroprevalence. Among the anti-HEV IgG positive subjects, only 1 had anti-HEV IgM while none tested positive for HEV-RNA. The present data demonstrate a higher seroprevalence of anti-HEV IgG than previously reported in the region.

Correlation between specific IgM levels and percentage IgG-class antibody avidity to Toxoplasma gondii / Correlação entre níveis de IgM específica e percentual de avidez de anticorpos da classe IgG ao Toxoplasma gondii

Toxoplasmosis is an usually asymptomatic worldwide disseminated infection. In its congenital presentation it may lead to abortion or fetal malformations. Antenatal evaluation is considered of paramount importance to identify seronegative women and allow for prophylaxis. Recent improvements in sensitivity of IgM tests has made IgM detection an extremely protracted acute phase marker, and IgG avidity evaluation test became necessary. Observation has shown that a correlation can be established between IgM levels and avidity percentages, suggesting that frequently the avidity test may not be necessary. In this study we analyzed Toxoplasma gondii IgM levels of 202 samples and their IgG avidity percentages, in order to define specific levels whose IgM quantification could by itself define serodiagnosis and therefore make the avidity evaluation unnecessary. We showed that for IgM levels bellow 2.0 and above 6.0 serodiagnosis of toxoplasmosis could be established without need of IgG avidity test. IgM levels between these two parameters are associated with varying avidity indexes highlighting the importance of its evaluation as a means to confirm toxoplasmosis. Following this demonstration it was possible to avoid the avidity test for 75 percent of the cases, to reduce the turnaround time and to reduce costs.

A Toxoplasmose é uma infecção universal e usualmente assintomática. A forma congênita, entretanto, pode resultar em aborto ou mal formações. Testes sorológicos estão indicados em situações onde há suspeita clínica, e na triagem pré-natal, quando são extremamente importantes para rastrear a infecção e orientar a gestante. O aumento da sensibilidade das técnicas para detecção de IgM, tornou necessário o desenvolvimento de recursos, como a avidez de IgG, visando obter novo marcador de infecção aguda. Embora exista correlação entre níveis de IgM e grau de avidez de IgG, a maioria dos testes de avidez associa-se a níveis baixos de IgM, sugerindo que o teste de avidez não fosse necessário. Portanto, correlacionamos níveis de IgM de 202 amostras com seu respectivo nível de avidez de IgG, dirigidos contra o Toxoplasma, objetivando estabelecer valores claros para a sua indicação. Pôde-se observar que, para IgM < 2,0 e > 6,0, a definição sorológica pode ser feita independentemente da avidez. Níveis de IgM dentro desse intervalo associam-se a índices variados de avidez e, portanto, ressaltam a importância deste teste para definição sorológica do quadro. Com essa abordagem, foi possível diminuir a indicação do teste de avidez em 75 por cento, reduzir o tempo para liberação dos resultados e o custo unitário do teste para IgM.

As novas facetas e a ameaça da gripe aviária no mundo globalizado / New aspects and the threat of an avian flu epidemic in a globalized world

A influenza ou, como é conhecida comumente, a gripe, é uma doença infecciosa aguda causada por um grupo de vírus (com mesmo nome) que acomete várias espécies de animais, desde felinos até aves, passando por humanos. Há cerca de 10 anos têm sido descritos, inicialmente em Hong Kong, surtos de gripe causados por vírus aviários em populações humanas. A seguir, foram descritos surtos na Holanda e no Canadá. Portanto, indaga-se: o mundo corre o risco de um novo surto semelhante ao de 1918, porém com uma população mundial quatro a cinco vezes maior? Qual a velocidade de disseminação desse vírus, visto que as viagens internacionais já não são feitas em navios lentos, mas sim em jatos supersônicos que dão a volta ao mundo em algumas horas? Antes de tudo, o que torna esse vírus tão problemático? Para nós, profissionais de laboratório, é preocupante a questão do diagnóstico etiológico dessas infecções. Como ressaltamos, os quadros de gripe podem ser causados por vários agentes. Portanto, o diagnostico etiológico, básico para intervenções terapêuticas e para que se defina a ocorrência da epidemia, passa a ter relevância ainda maior.

Influenza, or as it is best known, "flu", is an acute respiratory infection caused by a virus that affects many different animal species from felines to birds, including humans.Ten years ago, initialy in Hong Kong and after that in Holand and Canada, outbreaks of avian flu have been increasingly reported in human beings. The question is innevitable: are we in the surge of a new flu pandemic like the one we had in 1918? The perspective is even worse now that we have five times the world population and the international travels are no longer made in slow-going ships but instead in super fast jet planes. For us, laboratory professionals, the question of the laboratory diagnosis is crucial. Considering that so many different viruses are associated with respiratory infections and therapeutic measures depend on this definition, this subject assumes an even greater interest.

High prevalence of hepatitis C infection in a brazilian prision: identification of risk factors for infection

Hepatitis C virus (HCV) causes infectious hepatitis worldwide. It is transmitted mainly by blood products and sharing of intravenous paraphernalia during illicit drug use. High prevalence rates have been described among specific groups considered to be at higher risk for HCV infection, including prision inmates. The objectives of this study were: to determine the HCV Seroprevalence among inmates of Casa de Detençäo de Säo Paulo; identify risk factors for HCV infection; and to compare the seroprevalence of HCV to other blood borne or sexulally transmitted diseases. From December, 1993, to January, 1994, a total de 779 inmates were interviewed to collect information on sociodemographic status, sexual behavior, and past experience with illict drugs. Blood samples were obtained from 756 inmates for serological tests. 310 (41 percent) blood samples were positive for anti-HCV, 425 (56.2 percent) were negative, and 21 (2.8 percent) showed indeterminate results. In this population, we found a seroprevalence of 13.7 percent for HIV, 3.3 percent for syphylis (VDRL), and 68.1 percent for hepatitis B virus previous infection. Four variables were each identified as associated with a positive anti-HCV serologic test: a positive VDRL (OR = 2.631 IC 95 percent 1.08 to 6.36); a time of current imprisonment longer than 130 months (OR = 2.44 IC 95 percent 1.04 to 5.71); previous incarceration at Casa de Detençäo de Säo Paulo (OR = 1.73 IC 95 percent 1.19 to 2.52) and; illict drug use before admission to the Casa de Detençäo de Säo Paulo (OR = 1.64 IC 95 percent 1.15 to 2.33). The seroprevalence of HCV antibodies among the study populations was high (41 percent), indeed, one of the highest clusters of HCV infection recorded until now. Four variables were each shown to be associated with HCV infection. The simultaneous presence of these 4 analysis indicates most HCV infections occur prior to inprisonment, initiation of control measures to prevent continued transmission after incarceration should be done.

Cytomegalovirus infection in children with Down syndrome in a day-care center in Brazil

This study evaluates the transmission of CMV infection in 120 children aged 1 to 15 years with Down syndrome who attended a day-care center for handicapped children in São Paulo, Brazil. A blood sample was obtained from each children at the beginning of the study for detection of IgG and IgM cytomegalovirus (CMV) antibodies by an immunofluorescence assay. Samples of saliva and urine were obtained every 3 months from the children with CMV antibodies to detect shedding of the virus by culture in human foreskin fibroblasts, by detection of pp65 CMV-antigen and by a nested PCR assay. The prevalence of anti CMV-IgG antibodies was 76.6 per cent (92/120), and IgM anti-CMV antibodies were detected in 13 per cent (12/92) of the seropositive children. During the first viral evaluation, CMV was detected in the urine and/or saliva in 39/90 (43.3 per cent) of the seropositive children. In the second and third evaluations, CMV was detected in 41/89 (46 per cent) and in 35/89 (39.3 per cent) children, respectively. Detection of CMV was shown both in urine and saliva in 28/39 (71.8 per cnet), 19/41(46.3 per cent) and 20/35 (57.1 per cent) of the children excreting the virus, respectively...