RESUMO
Laboratory-based case confirmation is an integral part of measles surveillance programmes; however, logistical constraints can delay response. Use of RDTs during initial patient contact could enhance surveillance by real-time case confirmation and accelerating public health response. Here, we evaluate performance of a novel measles IgM RDT and assess accuracy of visual interpretation using a representative collection of 125 sera from the Brazilian measles surveillance programme. RDT results were interpreted visually by a panel of six independent observers, the consensus of three observers and by relative reflectance measurements using an ESEQuant Reader. Compared to the Siemens anti-measles IgM EIA, sensitivity and specificity of the RDT were 94.9% (74/78, 87.4-98.6%) and 95.7% (45/47, 85.5-99.5%) for consensus visual results, and 93.6% (73/78, 85.7-97.9%) and 95.7% (45/47, 85.5-99.5%), for ESEQuant measurement, respectively. Observer agreement, determined by comparison between individuals and visual consensus results, and between individuals and ESEQuant measurements, achieved average kappa scores of 0.97 and 0.93 respectively. The RDT has the sensitivity and specificity required of a field-based test for measles diagnosis, and high kappa scores indicate this can be accomplished accurately by visual interpretation alone. Detailed studies are needed to establish its role within the global measles control programme.
Assuntos
Vírus do Sarampo , Sarampo , Humanos , Brasil/epidemiologia , Testes de Diagnóstico Rápido , Reprodutibilidade dos Testes , Leitura , Imunoglobulina M , Anticorpos Antivirais , Sarampo/diagnóstico , Sarampo/epidemiologiaRESUMO
En el marco regional se mantienen algunos elementos del plan de acción original del 2011 para documentar y verificar la eliminación, y se proporcionan orientación sólida y actualizada que se ajusta a las nuevas situaciones epidemiológicas. Para cumplir los criterios de reverificación, los países en los que esas enfermedades son endémicas ahora tendrán que demostrar que no hay transmisión del virus del sarampión durante más de un año y que poseen la capacidad nacional para mantener la eliminación del sarampión y la rubéola
Assuntos
Síndrome da Rubéola Congênita , Programas de Imunização , Elementos Químicos , Sarampo , Vírus do SarampoRESUMO
BACKGROUND: Measles virus infection induces acute immunosuppression for weeks following infection, and also impairs preexisting immunological memory, resulting in "immune amnesia" that can last for years. Both mechanisms predispose the host to severe outcomes of subsequent infections. Therefore, measles dynamics could potentially affect the epidemiology of other infectious diseases. METHODS: To examine this hypothesis, we analyzed the annual mortality rates of children aged 1-9 years in Brazil from 1980 to 1995. We calculated the correlation between nonmeasles infectious disease mortality rates and measles mortality rates using linear and negative-binomial models, with 3 methods to control the confounding effects of time. We also estimated the duration of measles-induced immunomodulation. RESULTS: The mortality rates of nonmeasles infectious diseases and measles virus infection were highly correlated. This positive correlation remained significant after removing the time trends. We found no evidence of long-term measles immunomodulation beyond 1 year. CONCLUSIONS: These results support that measles virus infection could increase the mortality of other infectious diseases. The short lag identified for measles effects (<1 year) implies that acute immunosuppression was potentially driving this effect in Brazil. Overall, our study indicates disproportionate contributions of measles to childhood infectious disease mortality, highlighting the importance of measles vaccination.
Assuntos
Doenças Transmissíveis , Sarampo , Criança , Humanos , Vírus do Sarampo , Brasil/epidemiologia , Sarampo/epidemiologia , Terapia de ImunossupressãoRESUMO
Measles virus (MeV) is a paramyxovirus that infects humans, principally children. Despite the existence of an effective and safe vaccine, the number of cases of measles has increased due to lack of vaccination coverage. The World Health Organization (WHO) reports that the number of cases worldwide multiplied fourfold between January and March 2019, to 112,000. Today, there is no treatment available for MeV. In recent years, it has been demonstrated that natural extracts (herbal or algal) with antiviral activity can also work as reducing agents that, in combination with nanotechnology, offer an innovative option to counteract viral infections. Here, we synthetized and evaluated the antiviral activity of gold nanoparticles using garlic extract (Allium sativa) as a reducing agent (AuNPs-As). These nanoparticles actively inhibited MeV replication in Vero cells at a 50% effective concentration (EC50) of 8.829 µg/mL, and the selectivity index (SI) obtained was 16.05. AuNPs-As likely inhibit viral infection by blocking viral particles directly, showing a potent virucidal effect. Gold nanoparticles may be useful as a promising strategy for treating and controlling the infection of MeV and other related enveloped viruses.
Assuntos
Antivirais/farmacologia , Alho/química , Ouro/farmacologia , Vírus do Sarampo/efeitos dos fármacos , Sarampo/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Antivirais/química , Chlorocebus aethiops , Ouro/química , Humanos , Sarampo/virologia , Vírus do Sarampo/ultraestrutura , Extratos Vegetais/química , Células VeroRESUMO
Measles is a human infectious disease of global concern that is caused by the measles virus. In this study, we report the complete genome sequencing of one measles virus isolate, genotype D8, that was obtained directly from a urine sample in Boa Vista city, the capital of Roraima state in Brazil. Phylogenetic reconstruction grouped the genome described in this study with that of samples from Australia, South Korea, and Italy. To our knowledge, this is the first complete genome sequence of a wild-type measles virus reported from Latin America. Therefore, the present data strengthen the current knowledge on the molecular epidemiology of measles worldwide.
Assuntos
Vírus do Sarampo/genética , Sarampo/virologia , RNA Viral/genética , Brasil/epidemiologia , Surtos de Doenças , Genótipo , Humanos , Sarampo/epidemiologia , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNARESUMO
Here we reported the outbreak of measles cases caused by the genotype D8 measles virus for the first time in Jiangsu province in China, which was possibly imported by a foreign student from Laos. Throat swab specimens were collected, and used to isolate virus. 634-bp fragment of the N gene and 1854-bp fragment of H gene were amplified by reverse transcription-PCR and sequenced, respectively. Phylogenetic results indicated that they belonged to genotype D8 measles virus. Further epidemiology investigation showed that the adults with D8 measles virus infection did not receive measles vaccine before having measles. In China, almost all D8 genotype MeV only infected those population without receiving measles vaccine immunization. Therefore, it is still necessary to implement the supplement activity of measles immunization target adult with immunity gap.