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Montes de Oca-Aguilar AC, Pavón-Mendez MI, López-Ávila KB, Sosa-Bibiano EI, Rebollar-Téllez EA, Palacio-Vargas JA, Fernández-Figueroa EA, Loría-Cervera EN. Biting rhythms and infection rates of anthropophilic sand fly species (Diptera: Phlebotominae) in sites with different land use in southern Mexico. Acta Trop 2023; 248:107014. [PMID: 37696485 DOI: 10.1016/j.actatropica.2023.107014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/28/2023] [Accepted: 08/30/2023] [Indexed: 09/13/2023]
Abstract
Could tropical forest conversion shape sand fly (Diptera: Phlebotominae) biting rhythms and Leishmania infection rates? Using a Shannon trap, we estimated the bite rate and infection prevalence among anthropophilic sand flies at sites with different land use in southern Mexico. We estimated the expected monthly infection rate of the Leishmania parasite along the gradient and generated information on the biting rhythm of sand flies in a poorly characterized cutaneous leishmaniasis endemic region. We used generalized mixed linear and mixed additives models to evaluate differences in the biting rate, nocturnal activity, and inoculation rate of female sand flies, as well as their relationship with the loss of forest cover and environmental disparities recorded throughout the study area. Our results show that the loss of forest cover influences the biting rhythm of sand fly species and the potential number of infectious bites with Leishmania, but the greatest entomological and potential epidemiological risk continues to be associated with sylvatic areas (amplification events). Despite this, we detected that the effect of forest cover (%) on the entomological exposure seems to be also dependent on the sand fly species, and that, albeit to a lesser extent, Leishmania parasite is circulating in disturbed landscapes through generalist and competent sand fly vector species. We also found that land use change did not affect the nocturnal activity, however we detected that important vector species were active most of the time. Contrary to our expectation, temperature and humidity did not shape the biting rhythm of sand fly species. We discuss the limitations and epidemiological implications of our findings regarding the risk of contracting leishmaniasis in southern Mexico.
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Affiliation(s)
- A C Montes de Oca-Aguilar
- Laboratorio de Inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico.
| | - M I Pavón-Mendez
- Laboratorio de Inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
| | - K B López-Ávila
- Laboratorio de Inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
| | - E I Sosa-Bibiano
- Laboratorio de Inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
| | - E A Rebollar-Téllez
- Laboratorio de Entomología Médica, Departamento de Zoología de Invertebrados, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Mexico
| | - J A Palacio-Vargas
- Dirección de Prevención y Protección de la Salud de los Servicios de Salud del Estado de Yucatán, Mexico
| | - E A Fernández-Figueroa
- Núcleo B de Innovación en Medicina de Precisión, Instituto Nacional de Medicina Genómica, Mexico
| | - E N Loría-Cervera
- Laboratorio de Inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
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Manteca-Acosta M, Cueto GR, Poullain M, Santini MS, Salomón OD. Population dynamics of Nyssomyia whitmani (Diptera: Psychodidae) in domestic and peridomestic environments in Northeast Argentina, a tegumentary leishmaniasis outbreak area. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:1088-1098. [PMID: 37313956 DOI: 10.1093/jme/tjad061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/31/2023] [Accepted: 06/05/2023] [Indexed: 06/15/2023]
Abstract
In the present study, the temporal dynamics of the main vector of Leishmania braziliensis, Nyssomyia whitmani, was measured by monthly captures of phlebotominae sandflies during 5 consecutive years (from 2011 to 2016) in the Paranaense region of South America. The captures were performed in environments where the human-vector contact risk is high: domiciliary and peridomiciliary environments in a rural area endemic of tegumentary leishmaniasis. Nyssomyia whitmani was recorded as the dominant species of the phlebotominae ensemble in all domiciliary and peridomiciliary environments (House, Chicken Shed, Pigsty, and Forest Edge). Using generalized additive models, intra- and interannual fluctuations were observed, modulated by meteorological variables such as the minimum temperature and the accumulated precipitation 1 wk prior to capture. The installation of a pigsty by the farmer during the study period allowed us to observe and describe the so-called "pigsty effect" where the Ny. whitmani population was spatially redistributed, turning the pigsty as the environment that obtained the highest phlebotominae record counts, thus maintaining the farm overall abundance, supporting the idea that the environmental management of the peridomicile could have an impact on the reduction of epidemiological risk by altering the spatial distribution of the phlebotominae ensemble in the environments.
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Affiliation(s)
- Mariana Manteca-Acosta
- Centro Nacional de Diagnóstico e Investigación en Endemo-epidemias (CeNDIE), Administración Nacional de Laboratorios de Salud (ANLIS), Ministerio de Salud de la Nación, Buenos Aires, Argentina
| | - Gerardo Rubén Cueto
- Departamento de Ecología, Genética y Evolución, Instituto IEGEBA (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Matias Poullain
- Centro Nacional de Diagnóstico e Investigación en Endemo-epidemias (CeNDIE), Administración Nacional de Laboratorios de Salud (ANLIS), Ministerio de Salud de la Nación, Buenos Aires, Argentina
| | - María Soledad Santini
- Instituto Nacional de Parasitología (INP-Fatala Chaben), Administración Nacional de Laboratorios de Salud (ANLIS), Ministerio de Salud de la Nación, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Oscar Daniel Salomón
- Instituto Nacional de Medicina Tropical, Administración Nacional de Laboratorios de Salud (ANLIS), Ministerio de Salud de la Nación, Puerto Iguazú, Misiones, Argentina
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Fernández MS, Cueto GR, Manteca-Acosta M, Salomón OD. Nyssomyia whitmani (Diptera: Psychodidae) Activity From Sunset to Sunrise: A Two-Year Study in a Rural Area in Northeast Argentina. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:51-61. [PMID: 36308521 DOI: 10.1093/jme/tjac154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Indexed: 06/16/2023]
Abstract
We model the nocturnal patterns of the main vector of Leishmania braziliensis (Vianna) in the Paranaense region of South America, Nyssomyia whitmani (Antunes & Coutinho). Occurrence and abundance variation were analyzed by hourly periods, and in relation to sunrise and sunset to avoid differences in luminosity at fixed times throughout the year. The possible role of climatic and environmental variables on nocturnal activity curves was explored. A rotating light trap was operated biweekly in the peridomestic henhouse of a farm in Puerto Iguazú, from May 2016 to May 2018. Ny. whitmani, is the predominant Phlebotominae species (6,720 specimens captured), and is present throughout the night and seasons. Generalized additive models of nocturnal abundance of Ny. whitmani show a bell shape with an acrophase in the early evening. Models of abundance distribution as a function of total abundance showed significant nonlinear variations, only for the tertile of highest vector abundance, in the curves by hourly periods, and related to dawn, while female abundance relative to total abundance showed an asymptotic increasing curve, suggesting density-dependent events with abundance thresholds. Finally, temperature was the variable that best explained the pattern of abundance distribution of Ny. whitmani during the night, although triggers for scotophase activity due to internal clocks or luminosity could not be ruled out. The relationship of activity and abundance with climatic variables would also explain the nights of extraordinary abundance, and therefore of greater probability of vector-human and vector-reservoir contacts.
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Affiliation(s)
- María S Fernández
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires e Instituto de Ecología, Genética y Evolución de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (UBA-CONICET), Buenos Aires, Argentina
| | - Gerardo R Cueto
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires e Instituto de Ecología, Genética y Evolución de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (UBA-CONICET), Buenos Aires, Argentina
| | - Mariana Manteca-Acosta
- Centro Nacional de Diagnóstico e Investigación en Endemo-Epidemias (CeNDIE), Administración Nacional de Laboratorios de Investigación en Salud (ANLIS), Buenos Aires, Argentina
| | - Oscar D Salomón
- Instituto Nacional de Medicina Tropical, (INMeT), Administración Nacional de Laboratorios de Investigación en Salud, Puerto Iguazú, Argentina (ANLIS) y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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Santini MS, Cavia R, Quintana MG, Acosta MM, Salomón OD. Abundance of Lutzomyia longipalpis and Nyssomyia whitmani, the Leishmania spp. vectors in northeastern of Argentina: Are spatial and temporal changing patterns consistence? Vet Anim Sci 2022; 18:100268. [PMID: 36147513 PMCID: PMC9485211 DOI: 10.1016/j.vas.2022.100268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/26/2022] Open
Abstract
The spatial distribution of the species was the same in both periods. The seasonal pattern of abundance changes between periods. -The study defines the "where" and "when" to implement mitigation actions.
Lutzomyia longipalpis and Nyssomyia whitmani were incriminated as vectors of Leishmania sp. Spatial heterogeneity together with seasonal changes in abundance constitute important elements for the understanding of the dynamics of vector populations, and there are fundamental for the development of adequate prevention and control strategies. The aim of this work was to compare the spatial and seasonal abundance of Lu. longipalpis and Ny. whitmani at a city spatial scale between two periods separated by three years. To study the spatial distribution, we compared the abundance distribution of these species at two warm times, 2011 with 2014. Respect to inter-annual seasonal abundance changes, we compared the four seasons of the year between two periods (2011–2012 vs 2014–2016). The spatial distribution for both species were found to be distributed mainly in the same areas of the city in both periods. We change for: Respect to the seasonal pattern of abundance, we observed that seasonal patterns showed changes between periods. Our study defines the ‘where’ and ‘when’ implement the actions to mitigate leishmaniasis cases.
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de Oca-Aguilar ACM, Rebollar-Téllez EA, Sosa-Bibiano EI, López-Avila KB, Torres-Castro JR, Loría-Cervera EN. Effect of land use change on the phlebotomine sand fly assemblages in an emergent focus of cutaneous leishmaniasis in Yucatan, Mexico. Acta Trop 2022; 235:106628. [PMID: 35952923 DOI: 10.1016/j.actatropica.2022.106628] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/14/2022] [Accepted: 07/28/2022] [Indexed: 11/01/2022]
Abstract
As land use intensifies in tropical forests, it is expected that species assemblages will be modified and that key functions of these ecosystems will be affected. The latter scenario is important from a public health perspective, because the land use change has been linked the outbreaks of vector-borne diseases. In this study, we evaluated the response of Phlebotominae (Diptera: Psychodidae) assemblages and their pattern of co-occurrence in four sites with different land use in an emerging cutaneous leishmaniasis focus in Yucatan, Mexico. Our hypothesis is that the conservation status (as forest cover) will positively influence the structure and composition of sand flies' assemblages. Using three different traps over a period of five months, a sampling effort of 1, 440 night-traps was performed. A total of 7, 897 sand fly specimens belonging to six genera and 10 species were collected. Our hypothesis was partially achieved since sand fly diversity increased as forest cover increased and vice versa, however random patterns of co-occurrence in assemblages were detected among sites. Even though the high abundance of sand flies in the forest fragment suggests an amplification effect, our results show that different vector species directly dominate in each site. We discuss the potential implications of the nestedness of species dominance. We suggest that in this emerging focus and under the land use gradient, Lutzomyia cruciata and Psathyromyia cratifer could play a pivotal role in maintaining the transmission cycles of Leishmania. The apparent generalist or colonialist profile of Lu. cruciata in disturbed areas deserves attention, due to the potential risk of leishmaniasis "domiciliation". This information is essential to understand the eco-epidemiology of leishmaniasis and the factors associated with its emergence in Yucatan, Mexico.
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Affiliation(s)
- A C Montes de Oca-Aguilar
- Laboratorio de inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico.
| | - E A Rebollar-Téllez
- Laboratorio de Entomología Médica, Departamento de Zoología de Invertebrados, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Mexico
| | - E I Sosa-Bibiano
- Laboratorio de inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
| | - K B López-Avila
- Laboratorio de inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
| | - J R Torres-Castro
- Dirección de Prevención y Protección de la Salud de los Servicios de Salud del Estado de Yucatán, Mexico
| | - E N Loría-Cervera
- Laboratorio de inmunología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mexico
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de Souza Fernandes W, de Oliveira Moura Infran J, Falcão de Oliveira E, Etelvina Casaril A, Petilim Gomes Barrios S, Lopes de Oliveira SL, Gutierrez de Oliveira A. Phlebotomine Sandfly (Diptera: Psychodidae) Fauna and The Association Between Climatic Variables and The Abundance of Lutzomyia longipalpis sensu lato in an Intense Transmission Area for Visceral Leishmaniasis in Central Western Brazil. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:997-1007. [PMID: 35139201 DOI: 10.1093/jme/tjac006] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Indexed: 06/14/2023]
Abstract
The presence, abundance, and distribution of sandflies are strongly influenced by climate and environmental changes. This study aimed to describe the sandfly fauna in an intense transmission area for visceral leishmaniasis and to evaluate the association between the abundance of Lutzomyia longipalpis sensu lato (Lutz & Neiva 1912) (Diptera: Psychodidae) and climatic variables. Captures were carried out 2 yr (July 2017 to June 2019) with automatic light traps in 16 sites of the urban area of Campo Grande, Mato Grosso do Sul state. The temperature (°C), relative humidity (%), precipitation (mm3), and wind speed (km/h) were obtained by a public domain database. The Wilcoxon test compared the absolute frequencies of the species by sex. The association between climatic variables and the absolute frequency of Lu. longipalpis s.l. was assessed using the Spearman's correlation coefficient. A total of 1,572 sandflies into four species were captured. Lutzomyia longipalpis s.l. was the most abundant species and presented a significant correlation with the average temperature, humidity, and wind speed in different periods. Lutzomyia longipalpis s.l. was captured in all months, showing its plasticity in diverse weather conditions. We emphasize the importance of regular monitoring of vectors and human and canine cases, providing data for surveillance and control actions to continue to be carried out in the municipality.
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Affiliation(s)
- Wagner de Souza Fernandes
- Programa de Pós-Graduação em Doenças Infecciosas e Parasitárias, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
| | - Jucelei de Oliveira Moura Infran
- Programa de Pós-Graduação em Doenças Infecciosas e Parasitárias, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
- Laboratório de Parasitologia Humana, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
| | - Everton Falcão de Oliveira
- Programa de Pós-Graduação em Doenças Infecciosas e Parasitárias, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
- Instituto Integrado de Saúde (INISA), Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
| | - Aline Etelvina Casaril
- Laboratório de Parasitologia Humana, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
| | - Suellem Petilim Gomes Barrios
- Laboratório de Parasitologia Humana, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
| | - Samuel Lucas Lopes de Oliveira
- Faculdade de Ciências Farmacêuticas, Alimentos e Nutrição (FACFAN), Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
| | - Alessandra Gutierrez de Oliveira
- Programa de Pós-Graduação em Doenças Infecciosas e Parasitárias, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
- Laboratório de Parasitologia Humana, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, 79070-900, Brazil
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Moya SL, Szelag EA, Manteca-Acosta M, Quintana MG, Salomón OD. Update of the Phlebotominae Fauna with New Records for Argentina and Observations on Leishmaniasis Transmission Scenarios at a Regional Scale. NEOTROPICAL ENTOMOLOGY 2022; 51:311-323. [PMID: 34936066 DOI: 10.1007/s13744-021-00934-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
Phlebotominae are small insects distributed in the Americas from Canada to Argentina and Uruguay, counting with more than 500 neotropical species. Some of them have a vectorial role in the transmission of Leishmania Ross, the causative agent of leishmaniases, a group of worldwide distributed diseases with different clinical manifestations and transmission cycles. Our aim was to update the Phlebotominae fauna of Argentina and to make observations on the American Cutaneous (ACL) and Visceral Leishmaniasis (AVL) transmission scenarios, according to the distribution of proven or suspected Leishmania vector species and recent changes in land use. Primary data (entomological captures) and secondary data (review of 65 scientific publications with Phlebotominae records) were used. With 9 new records, 46 Phlebotominae species are now recorded through the area comprising 14 political jurisdictions and 6 phytogeographic provinces. Distribution maps were constructed for the 5 proven or incriminated Leishmania vector species, and the evidence supporting the vectorial incrimination of these species is discussed. Three main ACL transmission scenarios are described in the phytogeographic provinces of the Yungas, Chaco, and Paranaense, associated with deforestation processes, while the transmission scenarios of AVL are urban outbreaks and scattered cases in rural areas. We update the available knowledge on the Phlebotominae fauna present in Argentina, emphasizing its epidemiological relevance in the current context of the increasing frequency of ACL outbreaks and geographic spread of AVL.
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Affiliation(s)
- Sofía Lorián Moya
- Instituto Nacional de Medicina Tropical (INMeT), ANLIS "Dr. Carlos G. Malbrán", Ministerio de Salud de La Nación, Puerto Iguazú, Misiones, Argentina.
- Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina.
- Red de Investigación de La Leishmaniasis en Argentina (ReDILA), Resistencia, Argentina.
| | - Enrique Alejandro Szelag
- Red de Investigación de La Leishmaniasis en Argentina (ReDILA), Resistencia, Argentina
- Instituto de Medicina Regional, Universidad Nacional del Nordeste, Chaco, Argentina
| | - Mariana Manteca-Acosta
- Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina
- Red de Investigación de La Leishmaniasis en Argentina (ReDILA), Resistencia, Argentina
- Centro Nacional de Diagnóstico E Investigación en Endemo-Epidemias (CeNDIE), ANLIS "Dr. Carlos G. Malbrán", Ministerio de Salud de La Nación, Buenos Aires, Argentina
| | - María Gabriela Quintana
- Instituto Nacional de Medicina Tropical (INMeT), ANLIS "Dr. Carlos G. Malbrán", Ministerio de Salud de La Nación, Puerto Iguazú, Misiones, Argentina
- Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina
- Red de Investigación de La Leishmaniasis en Argentina (ReDILA), Resistencia, Argentina
- Instituto Superior de Entomología, Universidad Nacional de Tucumán, San Miguel de Tucumán, Argentina
| | - Oscar Daniel Salomón
- Instituto Nacional de Medicina Tropical (INMeT), ANLIS "Dr. Carlos G. Malbrán", Ministerio de Salud de La Nación, Puerto Iguazú, Misiones, Argentina
- Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina
- Red de Investigación de La Leishmaniasis en Argentina (ReDILA), Resistencia, Argentina
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Manteca-Acosta M, Cavia R, Utgés ME, Salomón OD, Santini MS. Peridomestic natural breeding sites of Nyssomyia whitmani (Antunes and Coutinho) in an endemic area of tegumentary leishmaniasis in northeastern Argentina. PLoS Negl Trop Dis 2021; 15:e0009676. [PMID: 34411102 PMCID: PMC8376073 DOI: 10.1371/journal.pntd.0009676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/22/2021] [Indexed: 11/21/2022] Open
Abstract
The scarce information about breeding sites of phlebotomines limits our understanding of the epidemiology of tegumentary leishmaniasis. Identifying the breeding sites and seasons of immature stages of these vectors is essential to propose prevention and control strategies different from those targeting the adult stage. Here we identified the rural breeding environments of immature stages of Ny. whitmani, vector species of Leishmania braziliensis in the north of Misiones province, Argentina; then we determined and compared the environmental and structural characteristics of those sites. We also identified the season of greatest emergence and its relationship with adult abundance. During a first collection period, between 28 and 48 emergence traps were set continuously for 16 months in six environments of the farm peridomicile and domicile: below house, chicken shed, experimental chicken shed, forest edge, pigsty and under fruit tree. Traps were checked and rotated every 40 nights. A total of 146 newly emerged individuals were collected (93.8% of them were Ny. whitmani), totaling an effort of 23,040 emergence trap-nights. The most productive environments were chicken shed and below house, and the greatest emergence was recorded in spring and summer. During a second collection period, emergence traps and light traps for adult capture were placed in the chicken shed and below house environments of eight farms. Emergence traps were active continuously during spring, summer, and early autumn. Environmental and structural characteristics of each environment were recorded. A total of 84 newly emerged phlebotomines (92.9% Ny. whitmani; 72,144 emergence trap-nights) and 13,993 adult phlebotomines (147 light trap-nights) were recorded in the chicken shed and below house environments. A positive correlation was also observed between trap success of newly emerged phlebotomines and of adults after 120 days. A high spatial variability was observed in the emergence of Ny. whitmani, with the number of newly emerged individuals being highest in soils of chicken sheds with the highest number of chickens and closest to forest edge. Moreover, below house was found to be as important as chicken sheds as breeding sites of Ny. whitmani. Management of the number of chickens in sheds, soil moisture and pH, and the decision of where to localize the chicken sheds in relation to the houses and the forest edge, might contribute to reduce the risk of human vector exposure and transmission of Leishmania.
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Affiliation(s)
- Mariana Manteca-Acosta
- Centro Nacional de Diagnóstico e Investigación en Endemo-epidemias, ANLIS-Malbrán, Ministerio de Salud de la Nación, Buenos Aires, Argentina
- Comité Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Regino Cavia
- Comité Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires e Instituto de Ecología, Genética y Evolución, Buenos Aires, Argentina
| | - María Eugenia Utgés
- Centro Nacional de Diagnóstico e Investigación en Endemo-epidemias, ANLIS-Malbrán, Ministerio de Salud de la Nación, Buenos Aires, Argentina
| | - Oscar Daniel Salomón
- Comité Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Instituto Nacional de Medicina Tropical, ANLIS-Malbrán, Ministerio de Salud de la Nación, Misiones, Argentina
| | - María Soledad Santini
- Centro Nacional de Diagnóstico e Investigación en Endemo-epidemias, ANLIS-Malbrán, Ministerio de Salud de la Nación, Buenos Aires, Argentina
- Comité Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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