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PubMed2004

Flea-borne Bartonella grahamii and Bartonella taylorii in bank voles.

Bartonella species are increasingly associated with a range of human and animal diseases. Despite this, we have a poor understanding of the ecology and epidemiology of many species, especially those circulating in wild populations. Previous studies have demonstrated that a diverse range of Bartonella species are abundant in wild rodent populations; little is known regarding their modes of transmission, although both direct and indirect routes have been suggested. In this study, with bank voles (Clethrionomys glareolus) as the host species, we demonstrate that the rodent flea Ctenophthalmus nobilis is a competent vector of at least two Bartonella species, B. grahamii, which has previously been associated with human infection, and B. taylorii. In contrast, no evidence of either horizontal or vertical transmission was seen in bank voles inoculated with B. taylorii maintained in an arthropod-free environment; this finding suggests that fleas may be essential for transmitting some Bartonella species.

Animals↗
PubMed2004

Parasites of domestic and wild animals in South Africa. XLIV. Fleas (Insecta: Siphonaptera: Pulicidae) collected from 15 carnivore species.

Fleas were collected from 61 wild carnivores belonging to 13 species in various nature reserves and on farms, two feral domestic cats in a nature reserve and a domestic dog in the city of Johannesburg. Eleven flea species, including two subspecies of one of these, belonging to six genera were recovered. Amongst these only Ctenocephalides felis felis and Ctenocephalides felis strongylus are considered specific parasites of carnivores. The remaining ten species normally infest the prey animals of the various carnivores.

Animals↗
PubMed1990

Infection of colonized cat fleas, Ctenocephalides felis (Bouché), with a rickettsia-like microorganism.

We report the ultrastructure of a rickettsia-like microorganism in a colonized population of the cat flea Ctenocephalides felis (Bouché). The microorganism occurs principally in the cytoplasm of midgut cells, but similar microorganisms were detected in the tracheal matrix, muscle, hypodermis, ovaries, and the epithelial sheath of the testes. The microorganism has a well-defined cell membrane consistent with rickettsia and measures 0.25-0.45 microns in diameter with lengths up to 1.5 microns. It was observed repeatedly in fleas of 1 laboratory colony, including newly emerged non-bloodfed specimens, but not in specimens from several other sources.

Alphaproteobacteria↗
PubMed2002

First molecular evidence of new Bartonella spp. in fleas and a tick from Peru.

Fleas, lice, and ticks collected in Peru in a suburban area of Cusco in November 1998 were tested by polymerase chain reaction for the presence of Bartonella DNA using primers amplifying a fragment of the intergenic spacer region (ITS) gene. Three new Bartonella genotypes were detected in Pulex fleas self-collected from the beds and clothes of schoolchildren and adults. A fourth new genotype was also detected from a tick found on a sheep in the same area. One of the genotypes is closely related to B. vinsoni subsp. berkhoffii, and the others seem to originate from unknown Bartonella species, whose medical importance has yet to be clarified.

Animals↗
PubMed2006

The flea, Megabothris abantis: an invertebrate host of Hepatozoon sp. and a likely definitive host in hepatozoon infections of the montane vole, Microtus montanus.

In searching for an invertebrate host for Hepatozoon sp. infecting the montane vole (Microtus montanus), we collected fleas, ticks, and mites from live-trapped voles and searched squash preparations for Hepatozoon oocysts. From 1989 through 1996, we identified six species of fleas in Grand Teton National Park: Megabothris abantis, Megabothris asio megacolpus, Aetheca wagneri, Peromyscopsylla selenis, Peromyscopsylla. hesperomys, and Hystrichopsylla dippiei dippiei. We found Hepatozoon oocysts only in M. abantis; we found no oocysts in mites or ticks. We conclude that M. abantis is an invertebrate host of Hepatozoon sp. and is likely to be the definitive host for theHepatozoon spp. of M. montanus.

Animals↗
PubMedDate not supplied

[Characteristics of digestion of blood of different animals by the flea Xenopsylla cheopis].

Under experimental conditions fleas X. cheopis engorged and assimilated blood of 4 species of rodents, man, pigeon and two species of reptiles. Histological investigations have shown that the structure of food clot, destruction rate of blood cells and general duration of digestion are changed considerably depending on the host's blood. In females the digestion of white mice blood to haematin at 23-24 degrees lasted not over 12 hours, the digestion of blood of hamsters and man - 12 to 20 hours, of guinea pigs and reptiles - 18 to 25 hours and of white rats and pigeons - from 20 to 30 hours. In males the digestion carries out somewhat slower. The above differences in blood digestion can apparently create unequal conditions for pathogenic microbes in the intestine of fleas that affects the preservation and reproduction of the agent in the organisms of these carriers.

Animals↗
PubMedDate not supplied

[Effect of the bacterial preparation, insectin, on the fleas Xenopsylla cheopis].

The effect of 0.2-2 mg/g of insectine (Bacillus insectus) upon the Ist-IInd stage larvae of X. cheopis is very negligible but it manifests itself in the subsequent low (9 to 30%) development and hatching of imagos. The III stage larvae are more resistent and after the effect of 10 mg/g of the preparation 9% of larvae formed cocoons which later developed into imagos. Adult fleas poorly responded to 0.2-2 mg/g of insectine. However, 10-30 mg/g of insectine caused in four days a mass death of fleas and their population decreased to 70% as compared to control.

Bacillus↗
PubMedDate not supplied

[Fertility changes in Leptopsylla segnis (Siphonoptera: Leptopsyllidae) fleas depending on the duration of their preliminary contact with the food source].

In experiments the fecundity of Leptosylla segnis was depended upon duration of the preliminary contact of the host (white mouse) with fleas of the same species. As the duration of the contact was promoted the daily mean number of eggs per female at first (at time of contact from 1 to 6 days) increased, then (at time of contact 7-12 days) declined and decreased below original level at 13-30 days of contact. It is supposed that observed changes in fleas fecundity were connected with the immune reactions of the host to the bites of insects.

Animals↗
PubMedDate not supplied

[The role of fleas (Siphonaptera) in the epizootiology of plague].

This review concerns the role of the fleas in survival and spread of the plague, their influence on the seasonal dynamics of the epizootics, and infection rates of these insects in different natural foci. The critical evaluation is given to the data which are used to calculate the flea transmission probability for mathematical simulation of plague epizootics.

Animals↗
PubMed1999

[The discovery by Paul-Louis Simond of the role of the flea in the transmission of the plague].

After Yersin's two fundamental discoveries of the plague bacillus and of the rat's role in its propagation, no one had sought to solve the riddle of how the bacillus itself spread and how it contaminated man. P. L. Simond was the first to realise that manipulating a rat that had recently died could be extremely dangerous whereas after a time lapse of several hours the same dead rat presented no risks to man. He was also the first to detect an insect bite as being responsible for the lesions he had observed at the beginning of bubonic plague outbreaks and called "precocious plyctenas". After having verified the presence of the bacillus in fleas of dying rats, on 2 June 1898 Simond carried out his princeps experiment on the transmission of plague to rats by fleas. From then onwards, disinsectisation was added to deratisation in plague prophylaxis.

Animals↗
PubMedDate not supplied

[Aging and changes in fecundity of the flea Leptopsylla segnis (Siphonaptera: Leptopsyllidae)].

In experiment, the mean diurnal fecundity of Leptopsylla segnis females increased during the first five days since the beginning of feeding on white mice and reached the maximum in the second five-day period (15.7-16.7 eggs per 1 female during a day). In subsequent period of stay on a host, an activity of egg laying gradually decreased. In flea females, which had lived on hosts for 40 days and more this index was 3.7 eggs. During the mean life longevity (23 days), the flea females lay about 260 eggs; the females, which have lived more than 40 days, produce above 400 eggs.

Aging↗
PubMedDate not supplied

[Effect of the prolonged contact of a flea population with plague bacteria on the infective activity of vetors].

Results of the experimental infection of fleas (X. cheopis) with the plague agent after their long (2.5 years, 19 generations) feeding on infected white mice showed no difference in the infection activity of these insects as compared to control ones. The authors question the hypothesis according to which a low frequency of protein-formation in some species of fleas is due to their long contact with the plague agent in the historical past.

Animals↗
PubMedDate not supplied

[Ecological factors that influence the dynamics of the total store of Daursk suslik fleas in the Transbaikal natural focus of plague].

Based on 20-year (1967-1987) studies of the dynamic of the total store of the imago of Daursk souslik fleas in the Transbaikal natural focus of plague and of changes in the abiotic and biotic parameters of the environment, the authors have identified factors that statistically significantly influence the study processes. The analysis was made by the nonlinear multiple regression test. One to three predictors of flea abundance have been detected for each month from May to April inclusive.

Animals↗
PubMedDate not supplied

[Observations of fleas of small mammals at the Gran Paradiso National Park (Italian Occidental Alps)].

The Siphonaptera of small mammals (nearly 200 rodents, insectivora and mustelids) of the Parco Nazionale del Gran Paradiso (Western Italian Alps) have been collected and studied during the years 1973-75. All the animals have been captured at altitudes ranging from 1570 to 2400 m during different seasons. Twelve genera and sixteen species have been identified, namely: Chaetopsylla (C.) homoea homoea from Mustela erminea; Hystrichopsylla (H.) talpae talpae from Clethrionomys glareolus; Rhadinopsylla (A.) integella integella from Clethrionomys glareolus and Microtus nivalis; Ctenophtalmus (C.) agyrtes verbanus from Pitymys multiplex (collected by Beaucournu); Ctenophthalmus (C.) solutus solutus from Apodemus flavicollis and Apodemus sylvaticus; Ctenophthalmus (Medioctenophthalmus) nivalis nivalis from Clethrionomys glareolus, Microtus nivalis and Pitymys multiplex; Doratopsylla dasycnema cuspis from Sorex araneus and Clethrionomys glareolus; Palaeopsylla soricis rosickyi from Sorex araneus; Leptopsylla segnis from Apodemus sylvaticus and Mus musculus; Peromyscopsylla bidentata bidentata from Clethrionomys glareolus and Microtus nivalis; peromyscopsylla fallax from clethrionomgs glareous; Amphipsylla sibirica ssp. from clethrionomys glareolus and microtus nivalis; Malaraeus (Amalaraeus), penicilliger kratachvili from Clethrionomys glareolus, Microtus nivalis and Mustela erminea; Myoxopsylla laverani from Eliomys quercinus; Callopsylla saxatilis from Apodemus flavicollis, Microtus nivalis and Mustela erminea. Species of fleas not yet described in Italy are: Chaetopsylla (C.) homoea homoea; Rhadinopsylla (Actenophthalmus) mesa; Ctenophthalmus (Medioctemophthalmus) nivalis nivalis; Callopsylla saxatilis. The genus Callopsylla is identified for the first time in Italy. New identification of hosts for the species of fleas already described in Italy are: for Rhadinopsylla (Actenophthalmus) integella integella: Clethrionomys glareolus; for Ctenophthalmus (C.) solutus solutus: Apodemus flavicollis and Apodemus sylvaticus. All the 15 male specimens of M. laverani from E. quercinus captured in the Parco Nazionale del Gran Paradiso have characters more similar to M. l. traubi than to M. l. laverani: only one long and a much shorter spine in the superior half of the movable process, a distinct tooth in the anterior margin of the movable half of the movable process, a distinct tooth in the anterior margin of the movable process, crochets of phallosome shorter and more gradually tapered, apex of fixed process very acuminated. To the contrary the shape of the movable process is similar to that of M. l. laverani. A point of particular interest is to be found also in 2 specimens of Amphypsilla of the sibirica group, respectively collected from Mustela erminea and Microtus nivalis. They have a very atypical distribution of the spine in an abnormally shaped movable process: the reasons of the abnormality are due to castration, probably of parasitic origin (absence of phallosome, tendons, etc.).

Animals↗
PubMed1976

The control of ticks, fleas and lice on dogs by means of a Sendran--impregnated collar.

Plastic collars impregnated with 9,4% Sendran effectively controlled adult Rhipicephalus sanguineus for a period of 49 days and immature ticks for a period possibly in excess of 70 days when fitted to four dogs. Four uncollared dogs served as controls. Although flea burdens were extremely low the collars were apparently effective for a period in excess of 70 days. A medicated collar killed all the ticks, fleas and lice on a severely parasited dog within a period of 48 hours.

Animals↗
PubMed1961

Methods for measuring insecticide susceptibility levels in bed-bugs, cone-nosed bugs, fleas and lice.

A standard kit is prepared and distributed by WHO for testing insecticide resistance in adult mosquitos, and it would seem advantageous to be able to use the filter papers impregnated with DDT and dieldrin contained in this kit for testing resistance in other insects. Experiments have been successfully conducted with a view to developing methods based on the use of these papers for testing susceptibility levels in bed-bugs, cone-nosed bugs, fleas and lice. The designs of the various test methods and the results obtained are described in this paper. The tests for bed-bugs and fleas have been adopted as provisional methods by the WHO Expert Committee on Insecticides; those for cone-nosed bugs and lice have been designated tentative methods, requiring further investigation prior to the drawing up of specifications.

Animals↗
PubMedDate not supplied

[The effect of the vole subspecies of the plague microbe on the viability of Callopsylla caspia fleas].

When infected with cultures of plague microbe reared at 28 C the experimental fleas showed no reliable differences in the mortality as compared to control ones. By contrast, the infection with agent cultures reared at 37 C as well as the infection on agonizing white mice caused a statistically reliable increase in the mortality in insects of both sexes. In the groups of fleas infected on white mice the most intensive mortality was observed during the first 24 hours after the infectious feeding that, apparently, is connected with the effect of toxins present in the blood of agonizing animals.

Animals↗