ABSTRACT
A incidência da dengue, doença viral transmitida pelo mosquito Aedes aegypti, vem crescendo em Porto Alegre ao longo dos anos, com recorde de casos registrados em 2022. Epidemias da doença parecem ocorrer de forma cíclica no município, com registros a cada três anos. Dada a influência de fatores climáticos no ciclo de vida do vetor, este trabalho buscou analisar a influência de determinantes meteorológicos na periodicidade de epidemias de dengue na capital gaúcha entre 2010 e 2022. Análises descritivas foram realizadas para averiguar o padrão dos indicadores climáticos e dos casos de dengue ao longo dos anos, ao passo que análises estatísticas foram feitas para avaliar a correlação entre os fatores climáticos e os casos autóctones registrados entre 2016 e 2022. Os resultados obtidos não apontaram padrões meteorológicos que se repetem a cada três anos e que poderiam explicar a ciclicidade observada. Ainda, não foram constatadas correlações entre temperatura, umidade e pluviosidade com casos autóctones de dengue no município, ao menos em nível quadrimestral. Para além destas análises, constatou-se expressivo aumento de casos em 2022, apesar dos esforços de controle desempenhados pelo poder público, o que aponta a necessidade de maior investimento em educação em saúde para a população. (AU)
The incidence of dengue, a viral disease transmitted by the Aedes aegypti mosquito, has been increasing in Porto Alegre over the years, with a record number of cases reported in 2022. Epidemics of the disease seem to occur cyclically in the city, with reports every three years. Given the influence of climatic factors on the vector's life cycle, this study aimed to analyze the influence of meteorological determinants on the periodicity of dengue epidemics in Porto Alegre between 2010 and 2022. Descriptive analyses were used to investigate the pattern of climatic indicators and dengue cases over the years, while statistical analyses were performed to evaluate the correlation between climatic factors and autochthonous cases registered between 2016 and 2022. The results did not point out meteorological patterns that repeat every three years and could explain the observed cyclicity. Furthermore, no correlations were found between temperature, humidity and rainfall and autochthonous dengue cases in the city, at least on a four-monthly basis. Beyond these analyses, a significant increase in dengue cases was observed in 2022, despite the efforts of the public authorities to control the disease, which highlights the need for greater investment in health education for the population. (AU)
Subject(s)
Climate , Aedes , Dengue , Meteorology , EpidemicsABSTRACT
ABSTRACT: Previous studies have demonstrated the antimicrobial activity of the peptide P34. In this study, the antiviral potential of P34 and the in vitro mechanism of action were investigated against bovine alphaherpesvirus type 1 (BoHV1). P34 exhibited low toxicity, a high selectivity index (22.9) and a percentage of inhibition of up to 100% in MDBK cells. Results from antiviral assays indicated that P34 did not interact with cell receptors, but it was able to inhibit the viral penetration immediately after pre-adsorption. In addition, BoHV1 growth curve in MDBK cells in the presence of P34 revealed a significant reduction in virus titer only 8h post-infection, also suggesting an important role at late stages of the replicative cycle. Virucidal effect was observed only in cytotoxic concentrations of the peptide. These findings showed that the antimicrobial peptide P34 may be considered as a potential novel inhibitor of in vitro herpesviruses and must encourage further investigation of its antiherpetic activity in animal models as well as against a wide spectrum of viruses.
RESUMO: A atividade antimicrobiana do peptídeo P34 já foi previamente demonstrada. Neste estudo, o potencial antiviral do P34 e o mecanismo de ação in vitro contra o alfaherpesvírus bovino tipo 1 (BoHV1) foram investigados. O P34 exibiu baixa toxicidade, alto índice de seletividade (22.9) e percentagem de inibição viral de até 100% em células MDBK. Os resultados dos ensaios antivirais indicaram que não interage com receptores celulares, mas é capaz de inibir a penetração viral, imediatamente após a pré-adsorção. Além disso, a curva de crescimento do BoHV1 em células MDBK na presença do P34 revelou uma significativa redução no título somente após 8h de infecção, sugerindo também uma importante atividade do peptídeo nas fases finais do ciclo replicativo. Efeito virucida frente / BoHV1 foi observado apenas em concentrações citotóxicas do peptídeo. Os dados obtidos indicam que o peptídeo antimicrobiano P34 pode ser considerado um potencial composto inibidor de herpesvírus, in vitro, e estimulam posteriores investigações sobre sua atividade anti-herpética em modelos animais, bem como contra outros vírus.
ABSTRACT
P34 is an antimicrobial peptide produced by a Bacillus sp. strain isolated from the intestinal contents of a fish in the Brazilian Amazon basin with reported antibacterial activity. The aim of this work was to evaluate the peptide P34 for its in vitro antiviral properties against canine adenovirus type 2 (CAV-2), canine coronavirus (CCoV), canine distemper virus (CDV), canine parvovirus type 2 (CPV-2), equine arteritis virus (EAV), equine influenza virus (EIV), feline calicivirus (FCV) and feline herpesvirus type 1 (FHV-1). The results showed that the peptide P34 exhibited antiviral activity against EAV and FHV-1. The peptide P34 inhibited the replication of EAV by 99.9% and FHV-1 by 94.4%. Virucidal activity was detected only against EAV. When P34 and EAV were incubated for 6 h at 37 °C the viral titer reduced from 10(4.5) TCID50 to 10(2.75) TCID50, showing a percent of inhibition of 98.6%. In conclusion, our results demonstrated that P34 inhibited EAV and FHV-1 replication in infected cell cultures and it showed virucidal activity against EAV. Since there is documented resistance to the current drugs used against herpesviruses and there is no treatment for equine viral arteritis, it is advisable to search for new antiviral compounds to overcome these infections.