Prevalence and genotyping of hepatitis C virus in blood donors in the state of Pará, Northern Brazil

Given the scarcity of epidemiological information on hepatitis C virus (HCV) infection in Northern Brazil, we determined the prevalence and genotypic frequency in blood donors in the state of Pará (PA). Blood samples from all of the blood donors at the Fundação HEMOPA (blood bank of PA) from 2004-2006 were screened for the presence of antibodies to anti-HCV and samples seroreactive to anti-HCV were further tested for HCV RNA using real-time PCR. In total, 116 HCV-RNA samples were genotyped, based on maximum likelihood phylogenetic analyses, using BioEdit, Modelgenerator, PHYML and FigTree software. The population consisted of 242,726 volunteers who donated blood from 2004-2006; the most common subgroup was males between the ages of 18-29 years old (37.30 percent). Within the whole group, 1,112 blood donors (0.46 percent) had indeterminate or positive serology; among these, 28.78 percent were males whose ages ranged from 18-29 years. A diagnosis of chronic HCV infection was confirmed for 304 donors (60.20 percent males; 66.45 percent were 30-49 years old), resulting in a prevalence of HCV RNA in 0.13 percent of the samples (304 of 242,726). HCV genotyping revealed a high frequency of genotype 1 (108/116) followed by genotype 3 (8/116). This study found HCV infection to be relatively infrequent in PA; genotype 1 was most commonly isolated. This information can help guide prevention and control policies aimed at efficient diagnosis and control measures.

Discriminação alélica do fator V da coagulação por PCR em tempo real: diagnóstico simples e preciso / Allelic discrimination of coagulation factor V by real time PCR: a simple and accurate diagnosis

Dentre as doenças cardiovasculares, a trombose venosa (TV) destaca-se pela associação entre fatores de riscos adquiridos e fatores genéticos. A resistência hereditária à proteína C ativada tem sido identificada como a principal causa dos casos de trombose venosa, sendo frequentemente associada à mutação fator V Leiden (G1694A). Em indivíduos homozigotos, o risco de trombose venosa é 50 a 100 vezes maior que em pacientes homozigotos normais, enquanto em pacientes heterozigotos o risco é de 5 a 10 vezes. Baseado na necessidade de avaliação e acompanhamento de pacientes com casos de trombose venosa e prevenção de seus respectivos familiares, foi desenvolvido um método simples de discriminação alélica do fator V da coagulação utilizando PCR em tempo real. Foram selecionados 67 pacientes com histórico de TV e 51 indivíduos sem histórico de TV. Primeiramente, a discriminação alélica do fator V foi realizada através de PCR convencional seguida de digestão enzimática (Mnl). Posteriormente, o diagnóstico foi realizado por PCR em tempo real. Ambos os métodos foram baseados no polimorfismo G1691A, sendo no segundo utilizado fluoróforos VIC e FAM para marcar os nucleotídeos G e A, respectivamente. A técnica de PCR-RFLP foi utilizada para diagnosticar 95 indivíduos homozigotos normais, 21 heterozigotos e 2 homozigotos FVL. Utilizando PCR em tempo real foram obtidos os mesmos resultados. A máxima similaridade entre os resultados obtidos por PCR em tempo real e PCR-RFLP indicou precisão significativa do novo método de discriminação e visualização alélica do fator V.

Among cardiovascular diseases, venous thrombosis is important due to the association between acquired and genetic risks factors. Hereditary resistance to activated protein C has been identified as the main cause of venous thrombosis, and is frequently associated to the factor V Leiden mutation (G1694A). In homozygotic individuals, the risk of venous thrombosis is 50 to 100 times higher that in normal patients, while in heterozygotic patients the risk is 5 to 10 times higher. Based on the need of evaluation and follow up of patients with venous thrombosis and prevention in their respective families, a simple method of allelic discrimination of coagulation V factor was developed using real time PCR. Sixty-seven patients with a history of venous thrombosis and 51 individuals without venous thrombosis were selected for this study. First, identification of the factor V allele was achieved through conventional PCR followed by enzymatic digestion (Mnl). Subsequently, diagnosis was attained by real time PCR. Both the methods investigated the G1691A polymorphism using VIC and FAM fluorophores to mark nucleotides G and A, respectively. By PCR-RFLP, 95 individuals were diagnosed as normal homozygotes, 21 as heterozygotes and 2 as homozygotic factor V Leiden individuals. The same results were obtained using real time PCR. Maximum similarity between the results of real time PCR and PCR-RFLP indicates high precision of the new method for allelic identification and visualization of factor V Leiden.

Casos notificados de malária no Estado do Pará, Amazônia Brasileira, de 1998 a 2006 / Notified Cases of Malaria in the State of Pará, Brazilian Amazon, from 1998 to 2006

Este estudo realizou um levantamento dos casos notificados de malária no Estado do Pará entre 1998 e 2006, com intuito de quantificar o risco de transmissão da doença, discriminar o número de casos por espécies de Plasmodium e destacar as áreas de maior incidência. Das 5.454.700 amostras sanguíneas examinadas, a positividade foi de 27,58 por cento (22,38 por cento Plasmodium falciparum; 76,11 por cento Plasmodium vivax; 0,31 por cento Plasmodium malariae e 1,20 por cento infecções mistas P. falciparum e P. vivax), sendo observada redução gradativa de notificações a partir de 2001. Além disso, constatou-se que sete municípios apresentaram incidência parasitária anual (IPA) alta entre 1998 e 2006 e outros 31 tiveram média dos nove anos de IPA≥50, sendo constatado aumento do número de municípios com IPA média e baixa. Em suma, o Estado do Pará apresentou redução significativa de casos notificados de malária, com tendência de aumento do número de municípios com IPA baixa e média, provavelmente reflexo das ações governamentais de controle e prevenção à malária na região.

The aim of this study was to carry out a survey of malaria cases reported in the state of Pará from 1998 to 2006 inorder to quantify the risk of disease transmission, to discriminate the number of cases by Plasmodium species and todetermine the areas of greater incidence. Among 5,454.700 blood samples examined, 27.58 per cent tested positive (22.38 per cent Plasmodium falciparum; 76.11 percent Plasmodium vivax; 0.31 percent Plasmodium malariae and 1.20 percent mixed infections of P. falciparum and P. vivax). A gradual reduction in notifications was observed, beginning in 2001. In seven cities there was ahigh Annual Parasite Incidence (API) between 1998 and 2006 and another 31 had average API of ≥50 over nine years.There was an increase in the number of cities with average or low API values. In summary, the state of Pará witnessed a significant reduction in the notification of malaria cases, with an increased trend in cities with low and average API values. This is probably a result of government actions for malaria control and prevention in that region.