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المؤلفون: César Náquira, Michael J. Levy, Renzo Salazar, Katty Borrini-Mayori, Aaron W. Tustin, Ricardo Castillo-Neyra
المصدر: The American Journal of Tropical Medicine and Hygiene
مصطلحات موضوعية: Chagas disease, Male, Bedbugs, animal structures, Trypanosoma cruzi, Feces, Bed bug, Virology, parasitic diseases, medicine, Insect Vectors/parasitology, Parasite hosting, Animals, Chagas Disease, Mice, Inbred BALB C, biology, Host (biology), Transmission (medicine), Trypanosoma cruzi/physiology, Chagas Disease/transmission, fungi, Feces/parasitology, Articles, biology.organism_classification, medicine.disease, Insect Vectors, Bedbugs/parasitology, Infectious Diseases, Vector (epidemiology), Mice, Inbred BALB C/parasitology, Parasitology, Female, Cimex lectularius, purl.org/pe-repo/ocde/ford#3.03.06 [https]
الوصف: Populations of the common bed bug, Cimex lectularius, have recently undergone explosive growth. Bed bugs share many important traits with triatomine insects, but it remains unclear whether these similarities include the ability to transmit Trypanosoma cruzi, the etiologic agent of Chagas disease. Here, we show efficient and bidirectional transmission of T. cruzi between hosts and bed bugs in a laboratory environment. Most bed bugs that fed on experimentally infected mice acquired the parasite. A majority of previously uninfected mice became infected after a period of cohabitation with exposed bed bugs. T. cruzi was also transmitted to mice after the feces of infected bed bugs were applied directly to broken host skin. Quantitative bed bug defecation measures were similar to those of important triatomine vectors. Our findings suggest that the common bed bug may be a competent vector of T. cruzi and could pose a risk for vector-borne transmission of Chagas disease.
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d2d810c05fdc36109f69070760e87ed6
http://europepmc.org/articles/PMC4347337 -
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المؤلفون: Renzo Salazar, Katty Borrini, Michael J. Levy, Corentin M. Barbu, César Náquira, Ricardo Castillo-Neyra
المساهمون: Castillo-Neyra, Ricardo, University of Pennsylvania, Department of Epidemiology, The Netherlands Cancer Institute, Universidad Peruana Cayetano Heredia (UPCH), Perelman School of Medicine, University of Pennsylvania [Philadelphia], Center for a Livable Future, Fogarty National Institutes of Health : 1D43TW008273
المصدر: Plos Neglected Tropical Diseases 1 (9), e3433. (2015)
PLoS Neglected Tropical Diseases
PLoS Neglected Tropical Diseases, Public Library of Science, 2015, 9 (1), pp.e3433. ⟨10.1371/journal.pntd.0003433⟩
PLoS Neglected Tropical Diseases, Vol 9, Iss 1, p e3433 (2015)مصطلحات موضوعية: Time Factors, Epidemiology, [SDV]Life Sciences [q-bio], Video Recording, Disease Vectors, Behavioral Ecology, 0302 clinical medicine, Medicine and Health Sciences, Photography, Triatoma, 0303 health sciences, biology, Ecology, Transmission (medicine), Chagas Disease/transmission, lcsh:Public aspects of medicine, Arthropod Vectors, Insect Vectors/physiology, Circadian Rhythm, Infectious Diseases, Female, purl.org/pe-repo/ocde/ford#3.03.06 [https], Research Article, Chagas disease, lcsh:Arctic medicine. Tropical medicine, lcsh:RC955-962, 030231 tropical medicine, Guinea Pigs, Context (language use), Motor Activity, Vector Biology, 03 medical and health sciences, Feeding Behavior/physiology, Triatoma infestans, medicine, Animals, Chagas Disease, 030304 developmental biology, Host (biology), Public Health, Environmental and Occupational Health, Biology and Life Sciences, lcsh:RA1-1270, Feeding Behavior, biology.organism_classification, medicine.disease, Triatoma/physiology, Insect Vectors, Vector (epidemiology), Biological dispersal, Zoology, Entomology
الوصف: Chagas disease affects millions of people in Latin America. The control of this vector-borne disease focuses on halting transmission by reducing or eliminating insect vector populations. Most transmission of Trypanosoma cruzi, the causative agent of Chagas disease, involves insects living within or very close to households and feeding mostly on domestic animals. As animal hosts can be intermittently present it is important to understand how host availability can modify transmission risk to humans and to characterize the host-seeking dispersal of triatomine vectors on a very fine scale. We used a semi-field system with motion-detection cameras to characterize the dispersal of Triatoma infestans, and compare the behavior of vector populations in the constant presence of hosts (guinea pigs), and after the removal of the hosts. The emigration rate – net insect population decline in original refuge – following host removal was on average 19.7% of insects per 10 days compared to 10.2% in constant host populations (p = 0.029). However, dispersal of T. infestans occurred in both directions, towards and away from the initial location of the hosts. The majority of insects that moved towards the original location of guinea pigs remained there for 4 weeks. Oviposition and mortality were observed and analyzed in the context of insect dispersal, but only mortality was higher in the group where animal hosts were removed (p-value
Author Summary Chagas disease is transmitted by triatomine bugs that actively disperse by walking and flying. The control of this vector-borne disease focuses on reducing or eliminating the insect vector populations. Most transmission of Trypanosoma cruzi, the causative agent of Chagas disease, involves insects living within or very close to households and feeding mostly on domestic animals. As animal hosts can be removed due to migration, slaughter, or death, it is important to understand how host availability can modify transmission risk to humans and to characterize the dispersal of triatomine vectors on a very fine scale. We used a semi-field system to characterize the dispersal of Triatoma infestans, and compare the behavior of vector populations in the constant presence of hosts and after the removal of the hosts. The emigration rate – net insect population decline in original refuges – following host removal was on average 19.7% of insects per 10 days compared to 10.2% in constant host populations. Activity of insects was significantly increased when hosts were removed. The removal of domestic animals in infested areas increases vector dispersal, possibly towards nearby human sleeping spaces.وصف الملف: application/pdf
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المصدر: Revista do Instituto de Medicina Tropical de São Paulo, Vol 45, Iss 5, Pp 269-274 (2003)
Revista do Instituto de Medicina Tropical de São Paulo; Vol. 45 No. 5 (2003); 269-274
Revista do Instituto de Medicina Tropical de São Paulo; Vol. 45 Núm. 5 (2003); 269-274
Revista do Instituto de Medicina Tropical de São Paulo; v. 45 n. 5 (2003); 269-274
Revista do Instituto de Medicina Tropical de São Paulo
Instituto de Medicina Tropical (IMT)
instacron:IMT
Revista do Instituto de Medicina Tropical de São Paulo, Volume: 45, Issue: 5, Pages: 269-274, Published: OCT 2003مصطلحات موضوعية: Adult, Male, Rural Population, Chagas disease, medicine.medical_specialty, lcsh:Arctic medicine. Tropical medicine, Adolescent, Urban Population, lcsh:RC955-962, Epidemiology, Trypanosoma cruzi, RC955-962, Antibodies, Protozoan, Enzyme-Linked Immunosorbent Assay, Vectorial control, Biology, Serology, Age Distribution, Seroepidemiologic Studies, Arctic medicine. Tropical medicine, parasitic diseases, Prevalence, medicine, Animals, Humans, Chagas Disease, T. cruzi infection, Child, Fluorescent Antibody Technique, Indirect, Gynecology, Chagas' disease prevalence, Chagas disease transmission, Infant, Newborn, Follow up studies, Infant, General Medicine, Middle Aged, medicine.disease, Infectious Diseases, Child, Preschool, Female, Brazil
الوصف: A prevalência da infecção pelo Trypanosoma cruzi foi avaliada no município de Berilo, Minas Gerais, Brasil, no período de janeiro a julho de 1997. Uma amostra de 2.261 indivíduos foi estudada sorologicamente mediante o teste de imunofluorescência indireta em sangue coletado em papel de filtro. A taxa de prevalência foi de 18% no total da população estudada e 50% em pessoas da área rural maiores de 30 anos. A percentagem de soropositividade foi 0,17% entre os menores de 10 anos estudados, o que sugere que a transmissão vetorial está controlada na área. Observamos uma diminuição na taxa de soroprevalência entre as pessoas nascidas após 1960 e 1970 o que teria relação com o início das ações de controle. Observou-se também uma redução na taxa de infecção pelo T. cruzi quando comparamos os nossos achados com as estimativas de infecção registradas em um estudo sorológico realizado em Berilo em 1983. The prevalence of Trypanosoma cruzi infection was evaluated in Berilo, Minas Gerais (MG), Brazil, from January to July 1997. A serological survey using the indirect immunofluorescence test (IFT) in dried blood collected on filter-paper was performed in a sample of 2,261 individuals. The overall prevalence rate of T. cruzi infection was 18%, and reached 50% in individuals older than 30 years from rural areas. The percentage of seropositivity was 0.17% among individuals younger than 10 years old, suggesting that vectorial transmission is controlled in the area. A decrease in prevalence rates among people born after 1960 and 1970 was observed and this appears to be correlated with the beginning of control programs. A reduction in T. cruzi infection rates was observed when comparing our results with the rates estimated in a serologic study carried out in Berilo in 1983(11).
وصف الملف: application/pdf; text/html
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المؤلفون: Faustino Torrico, Michal Svoboda, Juan Jijena, Cristina Alonso-Vega, Carine Truyens, Laurent Brutus, Myrna Virreira, Yves Carlier
المصدر: The American journal of tropical medicine and hygiene, 77 (1
مصطلحات موضوعية: Bolivia, Trypanosoma cruzi, Chagas Disease -- blood, DNA, Protozoan -- analysis, Trypanosoma cruzi -- classification, Parasitemia, Minicircle, Chagas Disease -- transmission, Polymerase Chain Reaction, law.invention, chemistry.chemical_compound, law, Pregnancy, Virology, Genotype, parasitic diseases, medicine, Animals, Humans, Chagas Disease, Pregnancy Complications, Infectious, Trypanosoma cruzi -- isolation & purification, Polymerase chain reaction, biology, Chagas Disease -- parasitology, Infant, Newborn, Kinetoplastida, Sciences bio-médicales et agricoles, DNA, Protozoan, biology.organism_classification, medicine.disease, Trypanosoma cruzi -- genetics, Infectious Disease Transmission, Vertical, Infectious Diseases, chemistry, Pregnancy Complications, Infectious -- blood, Pregnancy Complications, Infectious -- parasitology, Protozoa, Chagas Disease -- congenital, Parasitology, Female, DNA
الوصف: To better understand the factors involved in maternal-fetal transmission of Trypanosoma cruzi, we compared DNA levels-obtained by use of quantitative real-time PCR and parasitic genotypes determined by PCR amplification followed by hybridization-in Bolivian mothers and their congenitally infected newborns. Mothers and their neonates displayed markedly different parasitic DNA levels, as most maternal estimated parasitemias (> 90%) were < 10 parasites/mL, whereas those of 76% of their newborns were > 1,000 parasites/mL. Comparison of T. cruzi TcII sublineages infecting mothers and newborns showed identity, without evidence of mixed infection in mothers or neonates. Analysis of minor variants of TcIId-genotyped parasites using sequence class probes hybridizing with hypervariable domains of kDNA minicircles showed discrepancies in half of mother/newborn pairs.
Journal Article
Research Support, Non-U.S. Gov't
info:eu-repo/semantics/publishedوصف الملف: text/pdf; 1 full-text file(s): application/pdf
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b45029c4e62ed4fa178fb87625d83efb
http://www.documentation.ird.fr/hor/fdi:010040662
