995 resultados para Yellow mosaic virus
Resumo:
The present paper colligates the notions acquired in previous investigations, already published, and new observations upon diseases of the psittacidae, liable to be confused with psittacosis of parrots. The author calls attention to the indifference with regard to this question shown by investigators, even by those who dealt with the study of this disease on the occasion of the latest outbreak of psittacosis, in flagrant contrast with the researches upon the alterations induced by pathogenic agents of other diseases transmissible to man, when these agents pass through animals or when the latter are depositaries of the virus. This remark considerably enhances the importance of the presence paper from a hygienic and epidemiologic point of view, representing moreover a contribution to general knowledge and to veterinary medicine. The researches carried out since the appearance of the latest outbreak of psittacosis,-which occurred simultaneously with an epizooty in parrots lodged in aviary of the park of Agua Branca (Directory of Animal Industry of the State São Paulo)-led to the verification of the frequent existence in these animals of various diseases liable to be confused with psittacosis. These diseases are due to two kinds of pathogenic agents: virus and bacteria. In the first group there are to be found the diseases occasioned by the virus of human psittacosis, discovered by Western, Bedson and Simpson, and the disease me with in parrots coming from traders in S. Paulo. The infections by bacteria of the genus Salmonella and by those of other genera belong to the second group. As differential characters of the two infections due to virus, delineated on the strength of notions drawn from a detailed experimental study and from the literature on this subject, the following are given: ¹ Samples of our virus were sent, for comparison, to various investigators of psittacosis. Amongst them, Prof. M. Rivers acceded to our request; he found its nature to be different from that of the virus of psittacosis studiedby him. We are very much obliged to him for the attention he paid to this verification. Virus of psittacosis - Infectiousness: man, monkey, rabbit, mouse, hen, canary. Neurotropic affinity. Inclusions: small, protoplasmic. Exsiccation: the virus has good power of preservation. Symptoms: inactivity, drowsiness, frequent diarrhoea, oculo-nasal discharge and cough, coma. Duration: 4 to 5 days. Bodily lesions: congestion of intestines, splenomegaly. Virus of S. Paulo - Infects only psittacidae, particularly those of the genus Amazona. No localization in the nervous system. Large, nuclear. Is rapidly destroyed. Inactivity, inappetency, adynamia (drooping of the wings, indifference, leaning its beak against the bars of the cage in order not to fall down); profuse diarrhoea, of whitish stools, at times enterorrhagia; prolonged coma. 2 to 8 days. Foci of yellowish necrosis in liver, spleen and lung. At times, congestion of intestines. Characteristic features common to the two viruses.-They act in great dilutions, filter through tight candles though being partly retained, are preserved under glycerine or Bedson's solution, are stable at 55°C. heat and are destroyed by physical and chemical agents. Both virus diseases are very seldom met with in psittacidae: only once, amongst numberless sick parrots, the author met with a disease of the virus differring from that of psittacosis. This disease, greatly transmissible to man, ought to be more frequent, if it were common in parrots. On the contrary, bacteria cause diseases in these animals with great frequency, presenting variable characters, from a severe epizootic form, rapidly mortal, to ambulatory or silent forms, for the most part developing towards a cure or assuming a chronic character. Amongst the bacteria which cause the infection of this group the salmonellae predominate and amongst them the bacterium discovered by Nocard, as well as a species which in the course of this study is characterized under the name of Salmonella nocardi. The author believes that in the epizooty from which Nocard isolated his bacterium there was association of the virus-disease inducing the epizooty of that epoch in Paris with the bacterial disease, as must have happened in Argentina, where the disease was transmitted to man, and Santillan, according to Barros, isolated from the sick parrots bacteria of the genus Salmonella. The diseases of the two groups, that due to virus and that due to bacteria, are differentiated: Virus-diseases - Evolution: rapid, nearly always followed by death. Symptoms: sadness, profuse diarrhoea, of whitish stools, at times enterorrhagia, complete inappetency, adynamia, indifference, prolonged coma. Clinical forms: acute and subacute. Lesions: Foci of necrosis in liver and spleen without cellular reaction around the focus, yellow liver, multiple serositis. Presence of protoplasmic or nuclear granulations. Bacteriology: Complete lack or inconstant presence of bacteria in the organs and blood. Infectiousness of the organs and blood after filtration: positive. Bacterial diseases - Varies from one week to a month or more, not always fatal. Sadness, partial inappetency, tremblings, intensive thirst, mucous or mucosanguineous diarrhoea, lack of adynamia (reacts to stimulations and moves well at any time of the disease, though showing little disposition to locomotion), soiling of feathers. Frustrate, acute, subacute and chronic. Hepatic and intestinal cogestion, foci of necrosis in liver, spleen and lung with cellular reaction around the focus. Lack of granulations. Constant presence of bacteria in the organs and blood. Negative. The analysis of the litterature shows that the characteristic features of the diseases in parrots referred to parrot psittacosis, more frequently approach the bacterial diseases here described of these animals, a hypothesis which is reinforced by the observation of the greater frequency of infections...
Resumo:
The knowledge of the Ixodidae becomes every day, more and more important owing to the fact of the increasing number of diseases of man and animals they can transmit. In Brasil besides transmitting treponemosis, piroplasmosis and anaplasmosis to several domestic animals, the ticks are also responsible fo the transmission of the brazilian rocky mountain spotted fever (A. cajennense and Amblyomma striatum) and they can also harbour the virus of the yellow fever and even to transmit it in laboratory experiments (A. cajennense, O. rostratus). The Brazilian fauna of ticks is a small one and has no more than 45 well-established species belonging to the genus Argas, Ornithodoros, Ixodes, Haemaphysalis, Rhipicephalus, Boophilus, Amblyomma and Spaelaeorhynchus. The genus Amblyomma is the best represented one, with 67% of all species of ticks known in Brazil. One of the most important species in the Amblyomma cajennense owing to its abundance and its wide parasitism in many vertebrates: reptiles, birds and mammals, incluing man, who is much attacked by the larva, the nymph and the adult of this species. The other ticks who attack the man are the Amblyomma brasiliense (the pecari tick), in the forests, and the Ornithodoros, especially the species. O. rostratus and brasiliensis. Other species can bite the man, but only occasionally, like Amblyomma fossum, striatum, oblongogutatum etc. Argas persicus, Rhipicephalus sanguineus and Boophilus are very important species not only as parasites but specially because they transmit several diseases to animals. Some of the ticks of the brazilian wild animals are now also parasites of the domestic ones and vice-versa. Arga persicus var. dissimilis is very common among the poultry and transmits the Treponema anserinum (gallinarum). Boophilus microplus is very abundant on our domestic and wild ruminants (Bos, Cervus, Mazama etc.) and can also ben found on horse, dogs, Felis onca, Felis concolor etc., and it transmits to cattle piroplasmosis and anaplasmosis. Rhipicephalus sanguineus (an introduced species) is now very common on the dog, over all the country. The author recommend to give popular names to some brazilian ticks in order to make them more acquainted with the non scientific people. The author gives a classification of the superfamilia Ixoidoidea and keys to the determination of the different species of brazilian ticks. He creates a new family of Nuttallielidae to the so interesting tick, described by Bedford with the name of Nuttaliella namaqua in South Africa, a new variety of Argas persicus, the Argas persicus var. dissimilis nov. var. owing to the differences on the segment and on the size and morphology of the peritrema. He describes also the female of Amblyomma fuscum Nn. A great part of the author's work deals with the biology, life conditions and parasitism of many of the brazilian ticks in accordance with his personal and from other author's researches, especially in reference to Argas persicus, Ornithodoros rostratus, O. brasiliensis, Boophilus microplus, Rhipicephalus sanguineus, Amblyomma cajennense, A. pseudoconcolor, A. auriculare, A. rotundatum (= A. agamum) etc. The author gives a detailed report upon the parthenogenesis of A. rotundatum (A. agamum) that he first described in 1912 and gives also many references to other species of brazilian ticks, to teratological forms etc. He also gives a detailed report of the geographical distribution of brazilian ticks and of the peculiar conditions of its parasitism. The last part of this article deals with references to the species of ticks of some of the South American Republics namely Argentina, Bolivia, Colombia, Paraguay and Venezuela. Amblyomma testudinis Conil, A. neumanni Ribaga 1902 (= A. furcula Dõnitz 1909) and A. parvitarsum Nn. 1899 (= A. altiplanum Dios 1917), are found only in Argentina. It is given a special bibliography dealing with the brazilian ticks and four text figures and one plate.
Resumo:
1. - As seguintes especies de Triatomideos não puderam transmitir pela picada o virus da febre maculosa das Montanhas Rochosas a cobayas normaes, nos seguintes prazos após a sucção de animal infectado: Eutriatoma uhleri, 33, 47, 75 e 141 dias (1 exemplar); Triatoma protracta, 15 e 37 dias (1 exemplar), Triatoma infestans, 8 dias (15 exemplares), e Rhodnius prolixus, 2 dias (1 exemplar). Foi demonstrado por inoculaçao que o ultimo insecto ainda continha o virus vivo. 2. - Experiencias de transmissão mechanica, por picada interrompida em animal infectado e continuada immediatamente em animal são, foram tambem negativas, com as especies T. protracta e R. prolixus. Um unico insecto da primeira especie picou 2 vezes cada animal, emquanto que 22 exemplares da segunda especie picaram de 1 a 3 vezes cada cobaya. 3. - A inoculação de gottas de dejecções de um R. prolixus eliminadas 2 dias depois de sugar animal infectado, não produziu a infecção em cobaya normal, não obstante ter sido demonstrada a presença do virus no organismo do barbeiro, por inoculação do conteúdo estomacal em outra cobaya. 4. - Foram feitas experiencias para determinar o tempo de sobrevivencia do virus nos barbeiros, inoculando-se conteúdo intestinal a diversos intervallos depois da sucção de cobayas infectadas, com os seguintes resultados: T. infestans: positivo 1 vez em 24 horas e 2 vezes em 48 horas; negativo 2 vezes em 72. 96, 120 e 192 horas. P. megistus: positivo 3 vezes em 24 horas, 2 vezes em 48 horas e 1 vez em 72 horas; negativo 1 vez em 72 e 96 horas; resultado duvidoso ou sem valor (infecção intercorrente) 1 vez em 48 horas e 2 vezes a 72, 96 e 144 horas cada um. R. prolixus: positivo 1 vez em 24, 48 e 72 horas e negativo em 96 horas. 5. - Em vista dos resultados destas experiencias, feitas com 5 especies pertecentes a 4 generos de Triatomideos, torna-se muito pouco provavel que estes Hemipteros possam transmitir pela picada o virus da febre maculosa das Montanhas Rochosas, ou retel-o em seu organismo, em estado virulento, por mais de 2 a 4 dias.