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1.
Parasit Vectors ; 14(1): 587, 2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34838119

RESUMO

BACKGROUND: The Cimicidae are obligatory blood-feeding ectoparasites of medical and veterinary importance. We aim in the current study to assess the ability of MALDI-TOF MS to identify Cimex hirundinis swallow bugs collected in house martin nests. METHODS: Swallow bugs were picked out from abandoned nests of house martin swallows and identified morphologically to the species level. The bugs were randomly selected, dissected and then subjected to MALDI-TOF MS and molecular analyses. RESULTS: A total of 65 adults and 50 nymphs were used in the attempt to determine whether this tool could identify the bug species and discriminate their developmental stages. Five adults and four nymphs of C. hirundinis specimens were molecularly identified to update our MS homemade arthropod database. BLAST analysis of COI gene sequences from these C. hirundinis revealed 98.66-99.12% identity with the corresponding sequences of C. hirundinis of the GenBank. The blind test against the database supplemented with MS reference spectra showed 100% (57/57) C. hirundinis adults and 100% (46/46) C. hirundinis nymphs were reliably identified and in agreement with morphological identification with logarithmic score values between 1.922 and 2.665. Ninety-nine percent of C. hirundinis specimens tested were positive for Wolbachia spp. The sequencing results revealed that they were identical to Wolbachia massiliensis, belonging to the new T-supergroup strain and previously isolated from C. hemipterus. CONCLUSIONS: We report for the first time to our knowledge a case of human infestation by swallow bugs (C. hirundinis) in France. We also show the usefulness of MALDI-TOF MS in the rapid identification of C. hirundinis specimens and nymphs with minimal sample requirements. We phylogenetically characterized the novel Wolbachia strain (W. massiliensis) infecting C. hirundinis and compared it to other recognized Wolbachia clades.


Assuntos
Percevejos-de-Cama , Andorinhas/parasitologia , Wolbachia/isolamento & purificação , Animais , Percevejos-de-Cama/classificação , Percevejos-de-Cama/microbiologia , Aves , França , Humanos , Patologia Molecular , Filogenia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Simbiose
2.
Parasit Vectors ; 14(1): 441, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479609

RESUMO

The family Cimicidae includes obligate hematophagous ectoparasites (bed bugs and their relatives) with high veterinary/medical importance. The evolutionary relationships of Cimicidae and their hosts have recently been reported in a phylogenetic context, but in the relevant study, one of the six subfamilies, the bat-specific Latrocimicinae, was not represented. In this study the only known species of Latrocimicinae, i.e., Latrocimex spectans, was analyzed with molecular and phylogenetic methods based on four (two nuclear and two mitochondrial) genetic markers. The completed subfamily-level phylogeny of Cimicidae showed that Latrocimicinae is most closely related to Haematosiphoninae (ectoparasites of birds and humans), with which it shares systematically important morphologic characters, but not hosts. Moreover, in the phylogenetic analyses, cimicid bugs that are known to infest phylogenetically distant bat hosts clustered together (e.g., Leptocimex and Stricticimex within Cacodminae), while cimicid subfamilies (Latrocimicinae, Primicimicinae) that are known to infest bat hosts from closely related superfamilies clustered distantly. In conclusion, adding Latrocimicinae significantly contributed to the resolution of the phylogeny of Cimicidae. The close phylogenetic relationship between Latrocimicinae and Haematosiphoninae is consistent with long-known morphologic data. At the same time, phylogenetic relationships of genera within subfamilies are inconsistent with the phylogeny of relevant hosts.


Assuntos
Percevejos-de-Cama/classificação , Percevejos-de-Cama/genética , Quirópteros/parasitologia , Ectoparasitoses/parasitologia , Filogenia , Animais , Masculino
3.
J Med Entomol ; 58(1): 471-474, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-32740660

RESUMO

From the 1960s to the 1980s, with the implementation of nationwide 'Four-Pest Elimination' campaigns (bed bugs, Cimex lectularius L. and Cimex hemipterus (F.) (Hemiptera: Cimicidae), were listed as one of the targeted pests), bed bug infestations were gradually eliminated in most provinces in China. However, during the last two decades, reports of bed bug infestations in the Pearl River Delta of China have shown an upward trend. Up to now, the bed bug species occurring in this area was much less frequently reported. In this study, we used both morphological and molecular methods to accurately identify the species of bed bugs collected from the cities of Guangzhou and Foshan, China. Results indicated that no significant difference was observed in the mean pronotum width-to-length ratio of Guangzhou (2.6) and Foshan (2.4) specimens; however, both were significantly lower than that of a laboratory strain C. lectularius (3.1). The genetic distances of our specimens with C. hemipterus and C. lectularius were 0-0.2% and 22.2-22.6%, respectively. On the basis of the morphological characteristics and mitochondrial DNA sequence data, it can be affirmed that bed bugs collected from Guangzhou and Foshan were C. hemipterus.


Assuntos
Percevejos-de-Cama/classificação , Animais , Percevejos-de-Cama/anatomia & histologia , Percevejos-de-Cama/genética , China , Cidades , DNA Mitocondrial/análise , Feminino , Masculino , Ninfa/anatomia & histologia , Ninfa/classificação , Ninfa/genética
4.
J Parasitol ; 106(6): 835-842, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33378530

RESUMO

Numerous arthropod taxa are important in human and veterinary medicine. The salivary secretions and feces of arthropods can cause allergic reactions in host vertebrates or harbor pathogens. Also, bites can be a risk factor for secondary infections. Documenting the diversity of arthropods of medical and veterinary importance remains an important aspect of disease control and prevention. We provide new records of ectoparasitic arthropods from Mexico that are of potential medical or veterinary relevance. Scanning electron microscopy along with amplification and sequencing of a fragment of the mitochondrial gene (16S rRNA) was used to confirm some species identities. We report the cat louse Felicola subrostratus from cats and the chewing louse Heterodoxus spiniger from dogs, which are common ectoparasites but largely not reported in Mexico. The chigger Eutrombicula alfreddugesi is common on wild lizards (Squamata). For the first time, E. alfreddugesi is reported on Hemidactylus frenatus (common house gecko). This reptile has a close relationship with humans and its chiggers can cause dermatitis (i.e., trombiculiasis) or transmit pathogens. In addition, the common bed bug Cimex lectularius is reported for the first time in the state of Yucatan, an atypical area for its natural distribution. Phylogenetic analysis revealed that Cimex lectularius from Yucatan is closely related to genetic sequences of Cimex lectularius from China. Knowing the regional distribution of arthropods allows the design and implementation of prevention strategies for those that have potential roles as reservoirs or vectors.


Assuntos
Vetores Artrópodes/classificação , Doenças do Gato/parasitologia , Doenças do Cão/parasitologia , Infestações por Piolhos/veterinária , Lagartos/parasitologia , Infestações por Ácaros/veterinária , Animais , Vetores Artrópodes/ultraestrutura , Percevejos-de-Cama/classificação , Gatos , Cães , Feminino , Humanos , Iscnóceros/ultraestrutura , Infestações por Piolhos/parasitologia , Masculino , México , Microscopia Eletrônica de Varredura , Infestações por Ácaros/parasitologia , Sifonápteros/ultraestrutura , Trombiculidae/ultraestrutura
5.
Infect Genet Evol ; 85: 104536, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32927120

RESUMO

Bedbugs (Cimex lectularius and C. hemipterus) have reemerged as a major public health problem around the world. Their bites cause various skin lesions as well as discomfort and anxiety. Their role as potential vectors of various infectious agents is discussed. Accordingly, all suspected cases of bedbug infestations need to be documented thoroughly, with an unequivocal identification of the arthropods involved, if any are present. Although morphological identification is easily and quickly performed by entomologists or professionals, it can be challenging otherwise. Also, distinguishing Cimex lectularius and C. hemipterus requires entomological expertise. MALDI-TOF mass spectrometry has been recently presented as an additional tool for arthropod identification. In this study, we assess the use of MALDI-TOF MS for the identification of laboratory and wild strains of C. lectularius and C. hemipterus. Several body parts of laboratory reared C. lectularius specimens were used to develop a MALDI-TOF MS protocol for bedbug identification, which was later validated using five other laboratory and wild populations of C. hemipterus and C. lectularius. A total of 167C. lectularius and C. hemipterus bedbug specimens (98 laboratory specimens and 69 wild specimens) were submitted to MALDI-TOF MS analysis. 143/167 (85.63%) provided high quality MS spectra. The in-lab database was then upgraded with a total of 20 reference spectra from all bedbug populations and the rest of the MS spectra (123 bedbugs) were blind tested. All specimens were properly identified to the species level using MALDI-TOF MS and 86,25% (69/80) were aptly identified according to their origin with LSVs ranging from 1.867 to 2.861. MALDI-TOF MS appears as a reliable additional tool for the identification of these two anthropophilic species.


Assuntos
Percevejos-de-Cama/química , Percevejos-de-Cama/classificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Animais , Bases de Dados Factuais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-32630433

RESUMO

The bed bugs (Cimex lectularius and C. hemipterus) have undergone a significant resurgence worldwide since the 1990s. A compilation of findings from a database, including 2650 scientific publications from seven major medical databases, allowed us to document main evolutionary events, from fossil evidence, dating from 11,000 years ago, until the present that has led to the current worldwide expansion of Cimicid species. We present the hypotheses on the possible dispersion pathways of bed bugs in light of the major historical and evolutionary events. A detailed classification of the Cimicidae family and finally, an illustrative map displaying the current distribution of known Cimex species in each geographical ecozone of Asia, Europe, Africa, the Americas, and Australia are presented.


Assuntos
Percevejos-de-Cama , Filogenia , África , Animais , Ásia , Austrália , Percevejos-de-Cama/classificação , Europa (Continente) , Humanos , Estados Unidos
7.
Acta Vet Hung ; 66(4): 607-612, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30580536

RESUMO

Cimex lectularius, the common bedbug is an important, emerging pest of both veterinary and medical importance. Here a recently discovered, genetically distinct new species of the C. lectularius group is described morphologically, as Cimex pulveratus Hornok sp. nov.


Assuntos
Percevejos-de-Cama/classificação , Quirópteros , Ectoparasitoses/veterinária , Animais , Ectoparasitoses/parasitologia , Feminino , Masculino , Vietnã
8.
Parasit Vectors ; 10(1): 439, 2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28934957

RESUMO

BACKGROUND: Bats are regarded as the primary (ancestral) hosts of bugs of the family Cimicidae. The historically and economically most important species in the family is the common bedbug (Cimex lectularius), because of its worldwide occurrence and association with humans. This molecular-phylogenetic study was initiated in order to expand the knowledge on the phylogeny of cimicid bugs of bats, by investigating samples from Hungary, Romania (representing central-eastern Europe) and two further countries (South Africa and Vietnam). RESULTS: Altogether 216 cimicid bugs were collected (73 Ci. lectularius, 133 Ci. pipistrelli, nine Cacodmus ignotus and one Ca. sparsilis). Members of the Cimex lectularius species group were found both in the environment of bats (only Myotis emarginatus, which is a cave/attic-dwelling species) and on three crevice-dwelling bat species (two pipistrelloid bats and M. bechsteinii). On the other hand, Ci. pipistrelli always occurred off-host (near M. myotis/blythii, which are cave/attic-dwelling species). In addition, two Cacodmus spp. were collected from Pipistrellus hesperidus. The morphological characters of these specimens are illustrated with high resolution pictures. Analysis of cytochrome c oxidase subunit 1 (cox1) sequences generated from 38 samples indicated relative genetic homogeneity of Ci. pipistrelli, while the Ci. lectularius group had two haplotypes (collected from pipistrelloid bats in Hungary and Vietnam) highly divergent from other members of this species group. These results were confirmed with molecular and phylogenetic analyses based on the internal transcribed spacer 2 (ITS2). Bat-associated bugs morphologically identified as Ca. ignotus and Ca. sparsilis were different in their cox1, but identical in their ITS2 sequences. CONCLUSIONS: Molecular evidence is provided here on the existence of two new genotypes, most likely new species, within the Ci. lectularius species group. The relevant specimens (unlike the others) were collected from pipistrelloid bats, therefore the association of Ci. lectularius with different bat host species (pipistrelloid vs myotine bats) should be evaluated further as a possible background factor of this genetic divergence. In addition, Ca. ignotus is reported for the first time in South Africa.


Assuntos
Percevejos-de-Cama/classificação , Percevejos-de-Cama/genética , Quirópteros/parasitologia , Filogenia , Animais , Percevejos-de-Cama/anatomia & histologia , Europa (Continente) , Feminino , Genótipo , Haplótipos , Masculino
9.
J Med Entomol ; 54(4): 934-944, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28399298

RESUMO

The subfossil remains of 14 cimicids (Hemiptera: Cimicidae) were recovered during archaeological investigations of the Paisley Five Mile Point Cave site (35LK3400), an exceptionally well-dated (n = 229 radiocarbon dates) late Pleistocene-early Holocene rock shelter site in south-central Oregon. Nine of the specimens have been assigned to three modern species of Nearctic Cimicidae-Cimex antennatus Usinger & Ueshima, Cimex latipennis Usinger & Ueshima, and Cimex pilosellus (Horváth)-whereas the remaining five individuals were too fragmentary to positively identify. The chronology of the insect assemblage puts one specimen at circa 5,100 calibrated years before present (cal. yr BP), and the remaining 13 range in age from 9,400 to almost 11,000 cal. yr BP. Although fossil and subfossil cimicid remains have been recovered at other archaeological sites, the fossil record for bed bugs is largely undocumented. The Paisley Caves specimens thus far represent the oldest remains of the genus in probable contact with humans on record.


Assuntos
Distribuição Animal , Percevejos-de-Cama/classificação , Fósseis , Animais , Arqueologia , Cavernas , Feminino , Oregon
10.
J Med Entomol ; 54(4): 974-979, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28399302

RESUMO

The tropical bed bug is scientifically recognized as a significant public health problem. While there is an increased awareness about their resurgence by medical and life science committees, efficient bed bug management still remains unresolved. The solution may soon arise, as information about bed bugs' infestation dynamics and systematics are becoming more distinguishable. Recent developments in studies about bed bugs are based on molecular intervention by determining their genetic variation and phylogeography. The aim of this study is to assess the phylogenetic relationships and genetic diversity among the populations of tropical bed bugs inhabiting Malaysia. A molecular genotyping study was conducted with 22 tropical bed bug populations composed of three individuals per population. The mitochondrial (COI) gene was used as a marker. The data obtained were analyzed using the T-Coffee, ClustalX, MEGA 6.0, and PAUP software. The results showed one main monophyletic clade that consisted of two groups: Ch01 and Ch02. Ch02 consists of samples from the Bandar Hilir population, differing from the other populations studied by one singleton base. However, as there were no changes in the amino acid, this singleton genetic variation was considered to have no effect on genetic differentiation. Ch01 shows similarity with some sequence of Cimex hemipterus (F.) from Thailand, suggesting an international diversity connection. The disparity index apparently suggests that all isolates are homogeneous populations and are supported by the low value of the mean pairwise distance between isolates. This study will increase the knowledge about phylogeographic diversity of tropical bed bug in Malaysia.


Assuntos
Percevejos-de-Cama/classificação , Percevejos-de-Cama/genética , Variação Genética , Filogenia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genótipo , Proteínas de Insetos/genética , Malásia , Análise de Sequência de DNA
11.
Parasitol Res ; 116(1): 237-242, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27830371

RESUMO

The common bed bug Cimex lectularius, has been recently shown to constitute two host races, which are likely in the course of incipient speciation. The human-associated lineage splits from the ancestral bat-associated species deep in the history of modern humans, likely even prior to the Neolithic Period and establishment of the first permanent human settlements. Hybridization experiments between these two lineages show that post-mating reproductive barriers are incomplete due to local variation. As mating takes place in off-host refugia marked by aggregation semiochemicals, the present investigation tested the hypothesis that bed bugs use these semiochemicals to differentiate between refugia marked by bat- and human-associated bed bugs; this would constitute a pre-copulation isolation mechanism. The preference for lineage-specific odors was tested using artificial shelters conditioned by a group of either male or female bed bugs. Adult males were assayed individually in four-choice assays that included two clean unconditioned control shelters. In most assays, bed bugs preferred to rest in conditioned shelters, with no apparent fidelity to shelters conditioned by their specific lineage. However, 51 % of the bat-associated males preferred unconditioned shelters over female-conditioned shelters of either lineage. Thus, bed bugs show no preferences for lineage-specific shelters, strongly suggesting that semiochemicals associated with shelters alone do not function in reproductive isolation.


Assuntos
Percevejos-de-Cama/classificação , Percevejos-de-Cama/fisiologia , Quirópteros/parasitologia , Ectoparasitoses/parasitologia , Ectoparasitoses/veterinária , Animais , Percevejos-de-Cama/genética , Bioensaio , Feminino , Humanos , Hibridização Genética , Masculino , Odorantes/análise , Reprodução
12.
Artigo em Inglês | MEDLINE | ID: mdl-27086421

RESUMO

Bat bugs are blood-feeding insects of bats or warm blooded animals and humans. Since 2011, Leptocimex spp (Heteroptera: Cimicidae) has been reported in Thailand. However, microscopic examination of Leptocimex spp is complicated, especially when the entire body of the specimen is not available. To confirm the phenotypic identification of L. inordinatus from a limestone bat cave in Thailand, partial fragments of mitochondrial cytochrome c oxidase subunit 1 (COI) gene and 16S mitochondrial ribosomal DNA were PCR amplified and sequenced, which revealed 97% sequence identity with Cimicidae family members, being most similar to Cacodminae gen. sp. and C. vicinus, both bat bugs. Phylogenetic tree construction showed that L. inordinatus has a separate genetic lineage from that of with human bed bugs (Cimex hemipterus or C. lectularius), swallow bugs and other tick species. The presence of L. inordinatus in a bat-dwelling cave frequented by humans presents a potential public health problem requiring attention in particular regarding the possibility of zoonotic transmission of pathogens.


Assuntos
Percevejos-de-Cama/parasitologia , Cavernas/parasitologia , Quirópteros/parasitologia , Ectoparasitoses/parasitologia , Animais , Percevejos-de-Cama/classificação , DNA Mitocondrial/genética , DNA Ribossômico/genética , Humanos , Filogenia , Tailândia , Clima Tropical
13.
J Med Entomol ; 52(4): 566-72, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26335463

RESUMO

With the recent global resurgence of the bed bugs (Cimex lectularius L.), there is a need to better understand its biology, ecology, and ability to establish populations. Bed bugs are domestic pests that feed mainly on mammalian blood. Although bed bugs have not been implicated as vectors of pathogens, their biting activity inflicts severe insomnia and allergic reactions. Moreover, they have recently developed resistance to various insecticides, which requires further molecular research to determine genetic variation and appropriate interventions. Population dynamics, including genetic differentiation and genetic distance of 10 populations from the Midwest were analyzed in this study. The bed bug samples collected by pest control companies were genotyped using eight species-specific microsatellite markers. Results showed all eight markers were polymorphic, with 8-16 alleles per locus, suggesting high genetic diversity. The FST values were >0.25, signifying pronounced genetic differentiation. The G-test results also indicated high genetic differentiation among populations. The frequency of the most common allele across all eight loci was 0.42. The coefficient of relatedness between each of the populations was >0.5, indicative of sibling or parent-offspring relationships, while the FIS and its confidence interval values were statistically insignificant within the populations tested. The populations departed from Hardy-Weinberg equilibrium, possibly because of high heterozygosity. The genetic distance analysis using a neighbor-joining tree showed that the populations from Kansas City, MO, were genetically separate from most of those from Nebraska, indicating a geographic pattern of genetic structure. Our study demonstrated the effectiveness of using microsatellite markers to study bed bugs population structure, thereby improving our understanding of bed bug population dynamics in the Midwest. Overall, this study showed a high genetic diversity and identified several new alleles in the bed bug populations in the Midwest.


Assuntos
Percevejos-de-Cama/classificação , Percevejos-de-Cama/genética , Repetições de Microssatélites/genética , Animais , Feminino , Marcadores Genéticos/genética , Variação Genética/genética , Masculino , Missouri/epidemiologia , Nebraska/epidemiologia , Filogenia
14.
Parazitologiia ; 49(2): 119-27, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26314158

RESUMO

The data on new findings of ectoparasites (mites and insects) of bats (Chiroptera: Vespertilionidae) in the Western Sayan and Tuva are represented. The bat fly Basilia mongolensis mongolensis Theodor, 1966 was discovered in the territory of Russia for the first time. Gamasid mite Spinturnix bregetovae Stanyukovich, 1995 is new for the region. New hosts were described for some ectoparasites.


Assuntos
Ácaros e Carrapatos/anatomia & histologia , Percevejos-de-Cama/anatomia & histologia , Quirópteros/parasitologia , Dípteros/anatomia & histologia , Ectoparasitoses/veterinária , Ácaros e Carrapatos/classificação , Animais , Percevejos-de-Cama/classificação , Dípteros/classificação , Ectoparasitoses/parasitologia , Feminino , Masculino , Sibéria
15.
PLoS One ; 9(11): e113692, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25411789

RESUMO

Recently, the bed bug, Cimex lectularius L. has re-emerged as a serious and growing problem in many parts of the world. Presence of resistant bed bugs and the difficulty to eliminate them has renewed interest in alternative control tactics. Similar to other haematophagous arthropods, bed bugs rely on their olfactory system to detect semiochemicals in the environment. Previous studies have morphologically characterized olfactory organs of bed bugs' antenna and have physiologically evaluated the responses of olfactory receptor neurons (ORNs) to host-derived chemicals. To date, odorant binding proteins (OBPs) and odorant receptors (ORs) associated with these olfaction processes have not been studied in bed bugs. Chemoreception in insects requires formation of heteromeric complexes of ORs and a universal OR coreceptor (Orco). Orco is the constant chain of every odorant receptor in insects and is critical for insect olfaction but does not directly bind to odorants. Orco agonists and antagonists have been suggested as high-value targets for the development of novel insect repellents. In this study, we have performed RNAseq of bed bug sensory organs and identified several odorant receptors as well as Orco. We characterized Orco expression and investigated the effect of chemicals targeting Orco on bed bug behavior and reproduction. We have identified partial cDNAs of six C. lectularius OBPs and 16 ORs. Full length bed bug Orco was cloned and sequenced. Orco is widely expressed in different parts of the bed bug including OR neurons and spermatozoa. Treatment of bed bugs with the agonist VUAA1 changed bed bug pheromone-induced aggregation behavior and inactivated spermatozoa. We have described and characterized for the first time OBPs, ORs and Orco in bed bugs. Given the importance of these molecules in chemoreception of this insect they are interesting targets for the development of novel insect behavior modifiers.


Assuntos
Percevejos-de-Cama/fisiologia , Receptores Odorantes/metabolismo , Animais , Antenas de Artrópodes/metabolismo , Sequência de Bases , Percevejos-de-Cama/classificação , Comportamento Animal/efeitos dos fármacos , Mapeamento de Sequências Contíguas , Feminino , Biblioteca Gênica , Masculino , Dados de Sequência Molecular , Feromônios/química , Feromônios/farmacologia , Filogenia , Receptores Odorantes/química , Receptores Odorantes/classificação , Receptores Odorantes/genética , Alinhamento de Sequência , Análise de Sequência de RNA , Comportamento Sexual Animal/efeitos dos fármacos , Espermatozoides/metabolismo
16.
Sci Rep ; 4: 3836, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24452337

RESUMO

Pyrethroid resistance in bed bugs, Cimex lectularius, has prompted a change to combination products that include a pyrethroid and a neonicotinoid. Ten populations of bed bugs were challenged with two combination products (Temprid SC and Transport GHP). Susceptibility of these populations varied, with the correlated response of the two products indicating cross resistance. We imposed selection on three populations using label rate Temprid, and then reared progeny from unselected and selected strains. All selected strains were significantly less susceptible to Temprid SC than unselected strains. Temprid selected strains were also less susceptible to Transport. The pyrethroid component of Temprid showed a significantly higher LD50 in selected strains, but susceptibility to the neonicotinoid remained unchanged. Taken together these results indicate resistance to combination insecticides is present in field populations at levels that should be of concern, and that short-term selection affecting existing variance in susceptibility can quickly increase resistance.


Assuntos
Percevejos-de-Cama/classificação , Bioensaio/métodos , Guanidina/análogos & derivados , Resistência a Inseticidas , Inseticidas/farmacologia , Piretrinas/farmacologia , Animais , Percevejos-de-Cama/efeitos dos fármacos , Percevejos-de-Cama/crescimento & desenvolvimento , Guanidina/farmacologia , Humanos , Grupos Populacionais
17.
Parasitol Res ; 112(11): 3897-904, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23982311

RESUMO

Co-speciation between host-parasite species is generally thought to result in mirror-image congruent phylogenies. For the last several centuries, many bat species have been turning synanthropic, especially those that are hosted by bedbugs in Europe. There is evidence of only limited gene flow from the population of people to the population of bats. This study was focused on comparison of survival, development, and the reproduction rate based on cross-feeding experiments. In our research, we used two bedbugs groups of Cimex lectularius-bat- and human-associated and respectively as specific/non-specific host bat and commercial human blood. Both lineages show different behavior according to their host preferences. During the bat blood experiment, we found significant differences between both human- and bat-associated bedbugs (Log rank test fourth χ(2) = 9.93, p > 0.05; fifth χ(2) = 11.33, p < 0.05), while no differences occurred with the human blood experiment between the survival levels. In molting, differences between both groups were significant particularly in the case of the bat blood experiment (fourth χ(2) = 5.91, p < 0.05). In the case of the bat blood experiment, we found a higher probability of molting in bat-associated groups than in human-associated groups. In the case of the human blood experiment, molting probability was stable in both specific and non-specific, showing similar pattern in both cases for all stages. Our results indicate an occurrence of two ecotypes within the one species C. lectularius. These findings support earlier data about morphological and mitochondrial DNA differences. The differentiation of both lineages fits the concept of specific host choice.


Assuntos
Percevejos-de-Cama/classificação , Percevejos-de-Cama/fisiologia , Ecótipo , Especificidade de Hospedeiro , Animais , Sangue , Quirópteros , Europa (Continente) , Comportamento Alimentar , Humanos , Reprodução , Análise de Sobrevida
18.
Parasite ; 19(4): 381-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23193523

RESUMO

Bed bugs are hematophagous insects responsible for a re-emerging and challenging indoor pest in many countries. Bed bugs infestations may have health consequences including nuisance biting, cutaneous and systemic reactions. This resurgence can probably be attributed to factors such as increased international travel and development of resistance against insecticides. Resistance against pyrethroids has been reported several times from the USA and rarely in Europe. In France, very few data on bed bugs are available. The present study aimed to assess the infestation by bed bugs of a complex of two high-rise apartment buildings in the suburb of Paris and to evaluate their susceptibility to pyrethroid insecticides. We inspected for bed bugs 192 out of 198 apartments units (97%) and interviewed their residents. 76 (39.6%) apartments were infested. Among the 97 residents living in infested apartments, 53 (54.6%) reported bed bug bites. A total of 564 bed bugs were collected in the infested units. Bioassays showed that 54 out of 143 bed bugs were resistant to pyrethroids (37.8%; 95% confidence interval: 29.9-45.7%). DNA sequencing showed that all bed bugs tested (n=124) had homozygous L925I kdr-like gene mutation. The level of pyrethroid resistance found indicates that this phenomenon was already established in the site and prompts the need to reevaluate the wide use of pyrethroids to control bed bugs.


Assuntos
Percevejos-de-Cama , Habitação , Mordeduras e Picadas de Insetos/etiologia , Piretrinas , Animais , Sequência de Bases , Percevejos-de-Cama/classificação , Percevejos-de-Cama/genética , Roupas de Cama, Mesa e Banho/parasitologia , Bioensaio , DNA/química , DNA/isolamento & purificação , Técnicas de Genotipagem , Habitação/normas , Humanos , Mordeduras e Picadas de Insetos/epidemiologia , Resistência a Inseticidas , Dados de Sequência Molecular , Paris/epidemiologia , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência
19.
Parasitol Res ; 111(1): 457-69, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22392133

RESUMO

The bedbug, Cimex lectularius, is a well-known human ectoparasite that is reemerging after a long absence of several decades in developed countries of North America and Western Europe. Bedbugs' original hosts were likely bats, and the bedbugs are still common in their roosts. Using morphometry and sequences of mitochondrial cytochrome oxidase subunit I and 16S genes, we showed that the populations on bats and humans are largely isolated and differ in morphology. The character of the morphological difference suggests it to be due to adaptation to different hosts, namely adaptations to different sensory, feeding, and dispersal needs. Using the molecular data, we estimated the time of splitting into bat- and human-parasitizing groups using the isolation-with-migration model. The estimate is surprisingly long ago and seems to predate the expansion of modern human from Africa. The gene flow between bat- and human-parasitizing bedbugs is limited and asymmetric with prevailing direction from human-parasitizing populations to bat-parasitizing populations. The differentiation of the populations fits the concept of host races and supports the idea of sympatric speciation. Furthermore, our findings contradict recently formulated hypotheses suggesting bat roosts as a source of bedbug's resurgence as a human pest. Also, we extend the known host range of the bedbug by two bat species.


Assuntos
Percevejos-de-Cama/classificação , DNA Mitocondrial/genética , Ectoparasitoses/parasitologia , Filogenia , Animais , Percevejos-de-Cama/anatomia & histologia , Percevejos-de-Cama/genética , Quirópteros , DNA Mitocondrial/química , DNA Ribossômico/química , DNA Ribossômico/genética , Ectoparasitoses/veterinária , Complexo IV da Cadeia de Transporte de Elétrons/genética , Europa (Continente) , Evolução Molecular , Fluxo Gênico , Humanos , América do Norte , RNA Ribossômico 16S/genética
20.
J Travel Med ; 19(6): 373-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23379708

RESUMO

BACKGROUND: A dramatic increase of reported bedbug (Cimex lectularius and Cimex hemipterus) infestations has been observed worldwide over the past decade. Bedbug infestations have also been detected across a wide range of travel accommodations, regardless of their comfort and hygiene levels. Travelers are increasingly exposed to the risks of bedbug bites, infestation of personal belongings, and subsequent contamination of newly visited accommodations and their homes. METHODS: We searched Medline publications via the PubMed database. National bedbug recommendations, textbooks, newspapers, and Centers for Disease Control websites were also searched manually. DISCUSSION: To detect infested sites, avoid or limit bedbug bites, and reduce the risk of contaminating one's belongings and home, bedbug biology and ecology must be understood. A detailed search of their most classic hiding niches is a key to finding adult bedbugs, nymphs, eggs, and feces or traces of blood from crushed bedbugs. Locally, bedbugs move by active displacement to feed (bite) during the night. Bed, mattress, sofa, and/or curtains are the most frequently infested places. If you find bedbugs, change your room or, even better, the hotel. Otherwise, travelers should follow recommendations for avoiding bedbugs and their bites during the night and apply certain simple rules to avoid infesting other sites or their home. CONCLUSION: Travelers exposed to bedbugs can minimize the risks of bites and infestation of their belongings, and must also do their civic duty to avoid contributing to the subsequent contamination of other hotels and, finally, home.


Assuntos
Percevejos-de-Cama , Mordeduras e Picadas de Insetos , Controle de Insetos , Logradouros Públicos/normas , Animais , Percevejos-de-Cama/classificação , Percevejos-de-Cama/fisiologia , Saúde Ambiental , Humanos , Higiene/normas , Mordeduras e Picadas de Insetos/epidemiologia , Mordeduras e Picadas de Insetos/etiologia , Mordeduras e Picadas de Insetos/fisiopatologia , Mordeduras e Picadas de Insetos/prevenção & controle , Controle de Insetos/métodos , Controle de Insetos/normas , Viagem
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