Cats are not small dogs: is there an immunological explanation for why cats are less affected by arthropod-borne disease than dogs?

It is widely recognized that cats appear to be less frequently affected by arthropod-borne infectious diseases than dogs and share fewer zoonotic pathogens with man. This impression is supported by the relative lack of scientific publications related to feline vector-borne infections. This review explores the possible reasons for the difference between the two most common small companion animal species, including the hypothesis that cats might have a genetically-determined immunological resistance to arthropod vectors or the microparasites they transmit. A number of simple possibilities might account for the lower prevalence of these diseases in cats, including factors related to the lifestyle and behaviour of the cat, lesser spend on preventative healthcare for cats and reduced opportunities for research funding for these animals. The dog and cat have substantially similar immune system components, but differences in immune function might in part account for the markedly distinct prevalence and clinicopathological appearance of autoimmune, allergic, idiopathic inflammatory, immunodeficiency, neoplastic and infectious diseases in the two species. Cats have greater genetic diversity than dogs with much lower linkage disequilibrium in feline compared with canine breed groups. Immune function is intrinsically related to the nature of the intestinal microbiome and subtle differences between the canine and feline microbial populations might also impact on immune function and disease resistance. The reasons for the apparent lesser susceptibility of cats to arthropod-borne infectious diseases are likely to be complex, but warrant further investigation.

Desenvolvimento de ferramentas de bioinformática para a genotipagem dos vírus dengue, zika, chinkungunya e febre amarela / Development of bioinformatics tools for the genotyping of dengue, zika, chinkungunya and yellow fever virus

INTRODUÇÃO: Os Arbovírus transmitidos por mosquitos, como Dengue (DENV),Chikungunya (CHIKV), Zika (ZIKV) e Febre Amarela (YFV), são considerados importantes desafios para a saúde pública. Além do cenário causado pelo DENV, responsável por epidemias há décadas e endêmico em quase todo o país, a introdução do CHIKV e do ZIKV no Brasil traz grande preocupação. Os Arbovírus são transmitidos por mosquitos do gênero Aedes,particularmente Ae. aegypti e suas doenças relacionadas resultam em aumento dos custos financeiros associados ao diagnóstico e ao tratamento. MATERIAIS E MÉTODOS: Para facilitar o diagnóstico e o desenvolvimento de estratégias de prevenção e tratamento de forma eficiente, foram desenvolvidas ferramentas de bioinformática capazes de genotipar esses vírus baseando-se em modelos evolutivos apropriados de forma automática, precisa e rápida. Nesta plataforma, sequências destes arbovírus são selecionadas no Genbank por meio de um Sistema Configurável Automático de Mineração (SCAM), para obter um conjunto eficiente de sequências referências que foram utilizadas no desenvolvimento das ferramentas.RESULTADOS: Este processo envolveu o alinhamento das sequências referências seguidas por reconstruções de árvores filogenéticas. Para atribuir os genótipos às sequências dos usuários, a ferramenta analisa as sequências uma a uma, através da identificação pelo programa BLAST, seguido pelo alinhamento com o programa ClustalW e posteriormente com a reconstrução filogenética utilizando o programa PAUP*. A classificação genotípica ocorre quando as sequencias do usuário se agrupam filogeneticamente com o bootstrap igual ou superior a 70%. CONCLUSÃO: Essas novas ferramentas de genotipagem automáticas fornecem uma classificação precisa para esses arbovírus mesmo quando as sequências do usuário são oriundas de tecnologias de última geração (NGS), lendo, portanto, fragmentos curtos.

INTRODUCION: Mosquito-borne Arboviruses such as Dengue (DENV), Chikungunya (CHIKV), Zika (ZIKV) and Yellow Fever (YFV) are considered major public health challenges. In addition to the scenario caused by DENV, which has been responsible for epidemics for decades and endemic throughout most of the country, the introduction of CHIKV and ZIKV in Brazil is a major concern. Arboviruses are transmitted by mosquitoes of the genus Aedes, particularly Ae. Aegypti and its related diseases result in increased financial costs associated with diagnosis and treatment. MATERIAL AND METHODS: To facilitate the diagnosis, prevention and treatment strategies efficiently, bioinformatics tools have been developed for the genotyping of these viruses based on appropriate evolutionary models in na automatically, accurately and rapidly manner. In this platform, sequences of these arboviruses are selected in Genbank by means of an Automatic Mining Configurable System (SCAM), to obtain an efficient set of reference sequences that were used in the development of the tools. RESULT: This process involved the alignment of the reference sequences followed by phylogenetic tree reconstructions. To assign the genotypes to the user sequences, the tool analyzes the sequences one by one, through identification by the BLAST program, followed by the alignment with the ClustalW program and later with the phylogenetic reconstruction using the PAUP* program. The genotypic classification occurs when the user sequences are grouped phylogenetically with the bootstrap equal to or greater than 70%. CONCLUSION: These new automatic genotyping tools provide an accurate classification for these arboviruses even when the user sequences are derived from next-generation technologies (NGS), thus reading short fragments.

Arboviruses and their vectors in the Pacific--status report.

Three arboviruses have already caused epidemics in various Pacific Island countries and territories, and currently represent a direct threat to public health. The diseases concerned are all mosquito-borne and should be kept under careful surveillance. Dengue fever, which is a worldwide major public health problem, is mainly transmitted in the Pacific by the Aedes aegypti vector but also by other mosquitoes of this genus with varying ranges. Epidemic polyarthritis due to the Ross River virus is endemic in Australia. At least one major epidemic has occurred in the Pacific where various vector mosquito species occur. Japanese encephalitis is a zoonosis that can be transmitted to humans by mosquitoes of the genus Culex. Its area of distribution in Asia is expanding and the possibility of fresh incursions into the region should be borne in mind. This paper reviews the situation regarding these diseases in the Pacific and provides information on the way they are transmitted as well as on the biology of the mosquito vectors.

[The results of the serological examination of medium-sized mammals in the natural foci of arbovirus infections in central Siberia]. / Rezul'taty serologicheskogo obsledovaniia srednikh mlekopitaiushchikh v prirodnykh ochagakh arbovirusnykh infektsii Srednei Sibiri.

The serological survey of white hares (n = 8), squirrels (n = 118), and Asian chipmunks (n = 486) in the dark coniferous forests of Middle Siberia revealed tick-borne encephalitis virus antihemagglutinins only in the former two species (37.5 +/- 17.1 and 7.6 +/- 2.4%, respectively) and in the squirrel, there is a close seasonal relation between the parameters of immune interbred and those virophoricity of taiga tick nymphs.

Antibodies to certain arboviruses in humans from a flooded village in Egypt.

A study was carried out on 180 sera collected from inhabitants of a seepage flooded village (Begiram) in a Nile Delta governorate in Egypt. The aim of the study was to monitor the prevalence of certain arboviruses; some of them are known to be endemic in Egypt. Sera were screened by ELISA except for the HTN by IF, and the results indicated that WN and SFS exhibited the highest prevalence 45.5% followed by SFN (21%). These 3 viruses are known to be endemic in Egypt. The high prevalence of W.N. and S.F.S viruses in Begiram village in comparison to lower rates detected in sera from nearby Sharkqiya governorate collected almost at the same time may reflect the adverse effect of the environmental change in the flooded village. RNF virus which caused a major epidemic in Egypt in 1977 and continued to be circulating until 1980, its antibodies were detected only in those above 20 years of age with a prevalence rate of 5%. Antibodies against two tick borne viruses viz QRF and CCHF were also detected with low prevalence rate 2.75% and 1.1% respectively; also antibodies to the rodent-borne HTN virus were detected with prevalence rate 1.1%. Antibodies to mosquito borne SIN and BAT viruses were not detected in the tested sera.