-
Infection and Immunity Jul 2016The plague bacillus Yersinia pestis is unique among the pathogenic Enterobacteriaceae in utilizing an arthropod-borne transmission route. Transmission by fleabite is a... (Review)
Review
The plague bacillus Yersinia pestis is unique among the pathogenic Enterobacteriaceae in utilizing an arthropod-borne transmission route. Transmission by fleabite is a recent evolutionary adaptation that followed the divergence of Y. pestis from the closely related food- and waterborne enteric pathogen Yersinia pseudotuberculosis A combination of population genetics, comparative genomics, and investigations of Yersinia-flea interactions have disclosed the important steps in the evolution and emergence of Y. pestis as a flea-borne pathogen. Only a few genetic changes, representing both gene gain by lateral transfer and gene loss by loss-of-function mutation (pseudogenization), were fundamental to this process. The emergence of Y. pestis fits evolutionary theories that emphasize ecological opportunity in adaptive diversification and rapid emergence of new species.
Topics: Adaptation, Biological; Animals; Biological Evolution; Communicable Diseases, Emerging; Evolution, Molecular; Genetic Variation; Humans; Insect Vectors; Plague; Siphonaptera; Yersinia pestis
PubMed: 27160296
DOI: 10.1128/IAI.00188-16 -
Veterinary Parasitology May 2016
Topics: Animals; Ectoparasitic Infestations; Isoxazoles; Siphonaptera; Tick Control; Ticks
PubMed: 26992661
DOI: 10.1016/j.vetpar.2016.02.033 -
PLoS Pathogens Sep 2011Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a... (Review)
Review
Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague system and is a likely factor to explain some of plague's variability from small and regional to large scales. Here, we review effects of climate variables on plague hosts and vectors from individual or population scales to studies on the whole plague system at a large scale. Upscaled versions of small-scale processes are often invoked to explain plague variability in time and space at larger scales, presumably because similar scale-independent mechanisms underlie these relationships. This linearity assumption is discussed in the light of recent research that suggests some of its limitations.
Topics: Animals; Climate; Environment; Host-Pathogen Interactions; Humans; Insect Vectors; Plague; Rodentia; Siphonaptera; Temperature; Yersinia pestis
PubMed: 21949648
DOI: 10.1371/journal.ppat.1002160 -
Annual Review of Entomology Jan 2024vegetable and oilseed crops are attacked by several different flea beetle species (Chrysomelidae: Alticini). Over the past decades, most research has focused on two... (Review)
Review
vegetable and oilseed crops are attacked by several different flea beetle species (Chrysomelidae: Alticini). Over the past decades, most research has focused on two species, and , which are major pests of oilseed rape in North America. More recently, and especially after the ban of neonicotinoids in the European Union, the cabbage stem flea beetle, , has become greatly important and is now considered to be the major pest of winter oilseed rape in Europe. The major challenges to flea beetle control are the prediction of population dynamics in the field, differential susceptibility to insecticides, and the lack of resistant plant cultivars and other economically viable alternative management strategies. At the same time, many fundamental aspects of flea beetle biology and ecology, which may be relevant for the development of sustainable control strategies, are not well understood. This review focuses on the interactions between flea beetles and plants and summarizes the literature on current management strategies with an emphasis on the potential for biological control in flea beetle management.
Topics: Animals; Brassica; Coleoptera; Siphonaptera; Insecticides; Brassica napus; Ecology
PubMed: 38270984
DOI: 10.1146/annurev-ento-033023-015753 -
Open Veterinary Journal 2021Fluralaner (Bravecto) is an isoxazoline class compound that is the only topically applied systemic ectoparasiticide approved for dosing at up to 12-week intervals for...
BACKGROUND
Fluralaner (Bravecto) is an isoxazoline class compound that is the only topically applied systemic ectoparasiticide approved for dosing at up to 12-week intervals for flea and tick control in cats.
AIM
To describe veterinarian recommendations for ectoparasiticide medications used in the UK and France along with veterinary recommendations previously reported from the US, as well as to assess cat owners' experience with a commercial transdermal spot-on fluralaner formulation administered to cats in the US and similarly describe the experiences of cat owners from the UK or France who administered fluralaner for feline flea and tick prevention.
METHODS
Clients of participating veterinary practices in the US, UK, or France who were visiting the clinic for a routine wellness visit, were currently treating their cat with fluralaner (Bravecto), and had purchased at least two doses were asked to complete a short two-page survey about their experience with flea and tick medications including fluralaner and other products they may have been administered.
RESULTS
Owners in the US (451 cats), UK (512 cats), and France (520 cats) completed surveys. Most cat owners (66%-75%) had previously administered other flea and tick products. More than 94% of cat owners surveyed in each country were satisfied or very satisfied with fluralaner. The most frequently reported benefit of using fluralaner was the 12-week dosing interval, selected by 76% of respondents in the US, 82% in the UK, and 70% in France. 79%-88% of cat owners (depending on the country) thought that dosing with extended duration fluralaner was more convenient than dosing with monthly flea and tick products and 86%-89% of cat owners that had used other flea and tick products preferred fluralaner over the other flea and tick products.
CONCLUSION
Veterinarians in the US, UK, and France recommended 12 months of flea protection and 9-11 months of tick protection per year, even though, in this study, cat owners usually purchased 1-3 months of protection per year. A longer flea and tick dosing interval, as seen with fluralaner, correlates with higher user satisfaction and preference among cat owners. Owners identified the 12-week dosing interval and single dose efficacy as the top reasons for selecting the fluralaner product for their cat. In all three countries, most cat owners indicated that they were more likely to deliver doses of extended duration fluralaner on time, compared to flea and tick products dosed monthly.
Topics: Animals; Cats; France; Isoxazoles; Personal Satisfaction; Siphonaptera; Ticks; United Kingdom
PubMed: 34722211
DOI: 10.5455/OVJ.2021.v11.i3.19 -
Journal of Vector Borne Diseases 2022Fleas (Insecta, Siphonaptera) are important vectors of plague and murine typhus in many parts of the world. Currently, about 2700 flea species were described in the... (Review)
Review
Fleas (Insecta, Siphonaptera) are important vectors of plague and murine typhus in many parts of the world. Currently, about 2700 flea species were described in the world. The most common vector flea Xenopsylla cheopis is found throughout India, but X. astia, and X. brasiliensis are found less and limited in distribution associated with the domestic rats such as Rattus rattus, R. norvegicus, Mus musculus, and Bandicota bengalensis. Bubonic plague is a major flea-borne disease caused by the bacterial pathogen Yersinia pestis, transmitted from rats to humans via the rodent flea, X. cheopis. A major outbreak of plague and high mortality occurred in India. After 1966 with the 3 decadal intervals, plague cases occurred only during the year 1994 reported in 5 different states (Gujarat, Maharashtra, Karnataka, Uttar Pradesh, Madhya Pradesh and New Delhi and subsequently plague cases occurred during 2002 and 2004 after the one-decade interval in Himachal Pradesh (2002). Another outbreak of bubonic plague was reported in Dangud village, Barkhot tehsil, Uttarkashi district, Uttarakhand during October 2004. Ctenocephalides fleas are common in cats and dogs, which are the main vectors of bacteria rickettsiae, such as Rickettsia typhi, R. felis, R. conorii, and Bartonella henselae. Molecular and serological evidence also confirms the presence of R. typhi, R. conorii R. felis and B. henselae pathogens in cats and other fleas in India. Flea bites and flea-borne dermatitis are common in men and pet animals. Because of the re-emergence of the plague, updated information on fleas and flea-borne diseases are essential to control the flea vectors and flea-borne diseases in India. Hence, this comprehensive review updates the available information on fleas and fleas transmitted diseases in India.
Topics: Animals; Cats; Dogs; Flea Infestations; Humans; India; Mice; Plague; Public Health; Rats; Siphonaptera
PubMed: 35708399
DOI: 10.4103/0972-9062.328977 -
Parasitology Sep 2023Combining the biogeography and phylogenetic patterns of parasite-host associations allows a better understanding of the history of parasite–host interactions, which...
Combining the biogeography and phylogenetic patterns of parasite-host associations allows a better understanding of the history of parasite–host interactions, which can be achieved biogeographic regionalization incorporating phylogenetic information. Recently, the concepts of evoregions (regions where a majority of species evolved from one or several ancestors inhabiting these regions) and evolutionary transition zones (regions of high phylogenetic turnover) have been proposed, coupled with a classification approach for these concepts. We applied this approach to 206 flea species and 265 host species of the Palearctic and aimed to identify evoregions and evolutionary transition zones for both fleas and hosts and to understand whether these evoregions and transition zones match each other. We identified 5 evoregions with 3 transition zones for either fleas or hosts, but neither the positions and boundaries of the flea and host evoregions nor the transition zones coincided. Indications of multiple geographic centres of diversification of the same flea lineages suggested that (a) the common evolutionary history of fleas and hosts was characterized by multiple events other than codiversification and that (b) dispersal played an important role in flea and host assemblies. Barriers to dispersal could be represented by landscape features (deserts and mountain ranges) and/or climate differences.
Topics: Animals; Siphonaptera; Phylogeny; Flea Infestations; Mammals; Parasites; Host-Parasite Interactions
PubMed: 37705252
DOI: 10.1017/S0031182023000884 -
Parasites & Vectors Aug 2017The efficacy and safety of a novel isoxazoline compound, sarolaner (Simparica, Zoetis) and spinosad (Comfortis, Elanco) as a positive control were evaluated for the... (Review)
Review
BACKGROUND
The efficacy and safety of a novel isoxazoline compound, sarolaner (Simparica, Zoetis) and spinosad (Comfortis, Elanco) as a positive control were evaluated for the treatment and control of natural flea infestations on dogs in two randomised, blinded, multi-centric clinical trials conducted in 11 veterinary clinics in northeastern and southeastern states of Australia.
METHODS
A total of 162 client-owned dogs (80 in northern study and 82 in southern study) from 105 households were enrolled. Each household was randomly allocated to receive either sarolaner (Simparica, Zoetis) or spinosad (Comfortis, Elanco). Dogs were dosed on Days 0, 30 and 60 and physical examinations and flea counts were conducted on Days 0, 14, 30, 60 and 90. Efficacy assessments were based on the percentage reduction in live flea counts post-treatment compared to Day 0.
RESULTS
In the northern study, at enrolment, primary dogs had flea counts ranging from 5 to 772. At the first efficacy assessment on Day 14, sarolaner resulted in 99.3% mean reduction in live flea counts relative to Day 0, compared to 94.6% in the spinosad group. On Day 30, the sarolaner-treated group had mean efficacy of 99.2% compared to 95.7% in the spinosad-treated group, and on days 60 and 90, both groups had mean efficacies of ≥ 98.8%. In the southern study, at enrolment, primary dogs had flea counts ranging from 5 to 156. Both sarolaner and spinosad resulted in ≥ 96.7% mean reduction in live flea counts on Day 14. On Day 30, the sarolaner-treated group had mean efficacy of 99.5% compared to 89.7% in the spinosad-treated group, and on days 60 and 90, both groups had mean efficacies of ≥ 98.6%. No treatment-related adverse events were observed in either study.
CONCLUSIONS
A single monthly dose of sarolaner (Simparica) administered orally at 2-4 mg/kg for three consecutive months was well tolerated and provided excellent efficacy against natural infestations of fleas under a range of Australian field conditions including different climatic and housing conditions. Similar efficacy was observed with spinosad (Comfortis) after the second and third monthly treatments.
Topics: Administration, Oral; Animals; Azetidines; Clinical Trials as Topic; Dog Diseases; Dogs; Drug Combinations; Flea Infestations; Insecticides; Macrolides; Parasite Load; Siphonaptera; Spiro Compounds; Treatment Outcome
PubMed: 28814332
DOI: 10.1186/s13071-017-2321-3 -
Open Veterinary Journal 2022Fleas play a major role as vectors for many pathogens that affect humans and livestock. Wild animals, especially wild rodents, are the most important hosts, acting as...
BACKGROUND
Fleas play a major role as vectors for many pathogens that affect humans and livestock. Wild animals, especially wild rodents, are the most important hosts, acting as reservoir hosts for many flea species and pathogens.
AIM
This study aimed to identify seasonality and hosts of fleas that parasitize small wild mammals in Gharyan, north-western Libya.
METHODS
Fleas were collected from seasonally infested hosts from summer 2017 to winter 2018.
RESULTS
This survey identified three flea species: , and was collected from porcupines, from hedgehogs and jerboas, whereas from gundis. The highest flea prevalence was in porcupines (35.00%) and the lowest was in gundis (11.11%). The highest intensity was in porcupines (10.43 ± 4.37), and the lowest was in jerboas (1.28 ± 0.24). The highest mean flea abundance was among porcupines of 3.65, whereas in hedgehogs, jerboas and gundis were less than 0.50 flea/host. was collected during all seasons, while was collected during all seasons except winter, whereas was collected only in spring.
CONCLUSION
The finding in this study has increased our awareness that small wild mammals can act as hosts for medically important flea species. All collected flea species have a great specialty in choosing their hosts. Flea intensity is affected by seasonal variations.
Topics: Animals; Flea Infestations; Libya; Mammals; Seasons; Siphonaptera
PubMed: 35342725
DOI: 10.5455/OVJ.2022.v12.i1.3 -
Parasites & Vectors Jan 2014This review defines insecticide/acaricide resistance and describes the history, evolution, types, mechanisms, and detection of resistance as it applies to chemicals... (Review)
Review
This review defines insecticide/acaricide resistance and describes the history, evolution, types, mechanisms, and detection of resistance as it applies to chemicals currently used against fleas and ticks of dogs and cats and summarizes resistance reported to date. We introduce the concept of refugia as it applies to flea and tick resistance and discuss strategies to minimize the impact and inevitable onset of resistance to newer classes of insecticides. Our purpose is to provide the veterinary practitioner with information needed to investigate suspected lack of efficacy, respond to lack of efficacy complaints from their clients, and evaluate the relative importance of resistance as they strive to relieve their patients and satisfy their clients when faced with flea and tick infestations that are difficult to resolve. We conclude that causality of suspected lack of insecticide/acaricide efficacy is most likely treatment deficiency, not resistance.
Topics: Animals; Cat Diseases; Cats; Dog Diseases; Dogs; Insecticide Resistance; Insecticides; Siphonaptera; Ticks
PubMed: 24393426
DOI: 10.1186/1756-3305-7-8