RESUMO
Commercially available diagnostic test kits for detection of dengue virus (DENV) non-structural protein 1 (NS1) and anti-DENV IgM were evaluated for their sensitivity and specificity and other performance characteristics by a diagnostic laboratory network developed by World Health Organization (WHO), the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR) and the Pediatric Dengue Vaccine Initiative (PDVI). Each network laboratory contributed characterized serum specimens for the panels used in the evaluation. Microplate enzyme-linked immunosorbent assay (ELISA) and rapid diagnostic test (RDT formats) were represented by the kits. Each ELISA was evaluated by 2 laboratories and RDTs were evaluated by at least 3 laboratories. The reference tests for IgM anti-DENV were laboratory developed assays produced by the Armed Forces Research Institute for Medical Science (AFRIMS) and the Centers for Disease Control and Prevention (CDC), and the NS1 reference test was reverse transcriptase polymerase chain reaction (RT-PCR). Results were analyzed to determine sensitivity, specificity, inter-laboratory and inter-reader agreement, lot-to-lot variation and ease-of-use. NS1 ELISA sensitivity was 60-75% and specificity 71-80%; NS1 RDT sensitivity was 38-71% and specificity 76-80%; the IgM anti-DENV RDTs sensitivity was 30-96%, with a specificity of 86-92%, and IgM anti-DENV ELISA sensitivity was 96-98% and specificity 78-91%. NS1 tests were generally more sensitive in specimens from the acute phase of dengue and in primary DENV infection, whereas IgM anti-DENV tests were less sensitive in secondary DENV infections. The reproducibility of the NS1 RDTs ranged from 92-99% and the IgM anti-DENV RDTs from 88-94%.
Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Vírus da Dengue/imunologia , Imunoglobulina M/sangue , Kit de Reagentes para Diagnóstico , Proteínas não Estruturais Virais/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Sensibilidade e EspecificidadeRESUMO
Dengue fever and dengue haemorrhagic fever are important arthropod-borne viral diseases. Each year, there are â¼50 million dengue infections and â¼500,000 individuals are hospitalized with dengue haemorrhagic fever, mainly in Southeast Asia, the Pacific and the Americas. Illness is produced by any of the four dengue virus serotypes. A global strategy aimed at increasing the capacity for surveillance and outbreak response, changing behaviours and reducing the disease burden using integrated vector management in conjunction with early and accurate diagnosis has been advocated. Antiviral drugs and vaccines that are currently under development could also make an important contribution to dengue control in the future.
Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Dengue/epidemiologia , América/epidemiologia , Sudeste Asiático/epidemiologia , Dengue/prevenção & controle , Hospitalização/estatística & dados numéricos , Humanos , Controle de Insetos/métodos , Ilhas do Pacífico/epidemiologiaRESUMO
Anti-dengue virus immunoglobulin M kits were evaluated. Test sensitivities were 21%-99% and specificities were 77%-98% compared with reference ELISAs. False-positive results were found for patients with malaria or past dengue infections. Three ELISAs showing strong agreement with reference ELISAs will be included in the World Health Organization Bulk Procurement Scheme.
Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/diagnóstico , Imunoglobulina M/sangue , Kit de Reagentes para Diagnóstico , Dengue/virologia , Ensaio de Imunoadsorção Enzimática , Reações Falso-Positivas , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
A surveillance system to detect West Nile virus (WNV) was established in Cuba in 2002. WNV infection was confirmed by serologic assays in 4 asymptomatic horses and 3 humans with encephalitis in 2003 and 2004. These results are the first reported evidence of WNV activity in Cuba.