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1.
Emerg Infect Dis ; 30(7): 1454-1458, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38916725

ABSTRACT

Few cases of hantavirus pulmonary syndrome have been reported in northeastern Argentina. However, neighboring areas show a higher incidence, suggesting underreporting. We evaluated the presence of antibodies against orthohantavirus in small rodents throughout Misiones province. Infected Akodon affinis montensis and Oligoryzomys nigripes native rodents were found in protected areas of Misiones.


Subject(s)
Antibodies, Viral , Orthohantavirus , Animals , Argentina/epidemiology , Orthohantavirus/immunology , Orthohantavirus/classification , Orthohantavirus/isolation & purification , Antibodies, Viral/blood , Hantavirus Infections/epidemiology , Hantavirus Infections/veterinary , Hantavirus Infections/virology , Rodentia/virology , Rodent Diseases/epidemiology , Rodent Diseases/virology , Humans , Hantavirus Pulmonary Syndrome/epidemiology , Disease Reservoirs/virology
2.
Parasitology ; 149(3): 396-406, 2022 03.
Article in English | MEDLINE | ID: mdl-35264264

ABSTRACT

A cross-sectional survey to assess the prevalence of Enterobius vermicularis infection and its associated factors among the child population of infant, preschool and school age in the urban, rural and indigenous population of Iguazú city, in subtropical Argentina was presented. Additionally, the status of enterobiasis at country level was reviewed and analysed. Enterobius vermicularis presence was assessed employing an oviscopic serial sampling technique. Statistical analysis of socio-demographic determinants was performed by generalized linear mixed models at individual, household and community levels. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were used to gather national information about E. vermicularis prevalence spanning the decade 2010­2020. A total of 916 children from 470 families participated. Overall prevalence was 29.8%, with 25.3, 30.7 and 34.2% detected for children inhabiting urban, rural and indigenous villages, respectively. The multi-level analysis showed that the presence of E. vermicularis was mostly determined by individual (e.g. age, playing habits, previous pinworm infection) and household-level factors (e.g. family size, overcrowding conditions). Interestingly, WASH variables, such as waste disposal, analysed at community level were also important. Data were analysed to provide eco-epidemiological features of enterobiasis in a heterogeneous subtropical child population in the same territory but with different socio-sanitary realities. The importance of promoting multi-level actions against the determinants identified, to control this public health problem integratively was evidenced. The scoping review of national data updated the state of knowledge of this parasitosis, identifying risk determinants and gaps in knowledge at country level.


Subject(s)
Enterobiasis , Animals , Argentina/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Enterobiasis/epidemiology , Enterobius , Humans , Infant , Prevalence , Risk Factors
3.
Rev Panam Salud Publica ; 45: e83, 2021.
Article in English | MEDLINE | ID: mdl-34220995

ABSTRACT

OBJECTIVE: Determine and characterize potential risk areas for the occurrence of cutaneous leishmaniasis (CL) in Latin America (LA). METHOD: Ecological observational study with observation units defined by municipalities with CL transmission between 2014-2018. Environmental and socioeconomic variables available for at least 85% of the municipalities were used, combined in a single database, utilizing the R software. The principal component analysis methodology was combined with a hierarchical cluster analysis to group clusters of municipalities based on their similarity. The V-test was estimated to define the positive or negative association of the variables with the clusters and separation by natural breaks was used to determine which ones contributed the most to each cluster. Information on cases was also incorporated in the analyses to attribute CL risk for each cluster. RESULTS: This study included 4,951 municipalities with CL transmission (36.5% of the total in LA) and seven clusters were defined by their association with 18 environmental and socioeconomic variables. The historical risk of CL is positively associated with the Amazonian, Andean and Savannah clusters in a decreasingly manner; and negatively associated with the Forest evergreen, Forest/crop and Forest/populated clusters. The Agricultural cluster did not reveal any association with the CL cases. CONCLUSIONS: The study made it possible to identify and characterize the CL risk by clusters of municipalities and to recognize the epidemiological distribution pattern of transmission, which provides managers with better information for intersectoral interventions to control CL.

4.
Rev Panam Salud Publica ; 45: e49, 2021.
Article in Spanish | MEDLINE | ID: mdl-33936185

ABSTRACT

OBJECTIVE: Determine and characterize areas at potential risk for the occurrence of cutaneous leishmaniasis (CL) in Latin America. METHOD: Ecological observational study with observation units defined by municipalities with CL transmission during 2014-2018. Environmental and socioeconomic variables available for at least 85% of municipalities were combined in a single database, using R software. Principal component analysis was combined with hierarchical cluster analysis for the formation of clusters of municipalities according to their similarity. The V-test was used to define positive or negative association of variables with clusters and separation by natural divisions to determine which contributed more to each cluster. Cases were included to attribute CL risk for each cluster. RESULTS: The study included 4 951 municipalities with CL transmission (36.5% of municipalities in Latin America); seven clusters were defined by their association with 18 environmental and socioeconomic variables. Historical risk of CL is associated positively and in descending order with the Amazonian, Andean, and Savanna clusters; and negatively with the Forest/perennial, Forest/cultivated, and Forest/populated clusters. The Agricultural cluster showed no association with CL cases. CONCLUSIONS: The study made it possible to identify and characterize CL risk by clusters of municipalities and to understand the characteristic epidemiological distribution patterns of transmission, providing program managers with better information for intersectoral interventions to control CL.


OBJETIVO: Determinar e caracterizar as áreas de risco de ocorrência de leishmaniose cutânea na América Latina. MÉTODO: Estudo observacional ecológico com unidades de observação definidas por municípios com transmissão de leishmaniose cutânea entre 2014 e 2018. Foram usadas as variáveis ambientais e socioeconômicas disponíveis em 85% ou mais dos municípios, reunidas em uma única base de dados com o uso do software R. A metodologia de análise de componentes principais foi combinada a uma análise de conglomerados com agrupamento hierárquico para formar conglomerados de municípios por semelhança. O teste V foi usado para estabelecer a associação (positiva ou negativa) das variáveis com os conglomerados e uma separação por divisões naturais foi usada para determinar as variáveis que mais contribuíram em cada conglomerado. Os casos foram incluídos para avaliar o risco de leishmaniose cutânea em cada conglomerado. RESULTADOS: A amostra do estudo compreendeu 4.951 municípios com transmissão de leishmaniose cutânea (36,5% do total na América Latina). Foram definidos sete conglomerados por apresentarem associação com 18 variáveis ambientais e socioeconômicas. Foi observada associação positiva e decrescente do risco histórico de leishmaniose cutânea com os conglomerados Amazônico, Andino e Savana e negativa com os conglomerados Mata/perene, Mata/cultivo e Mata/povoado. O conglomerado Agrícola não demonstrou associação com casos de leishmaniose cutânea. CONCLUSÕES: Este estudo permitiu identificar e caracterizar o risco de leishmaniose cutânea por conglomerados de municípios e conhecer o padrão epidemiológico de distribuição da transmissão da doença, oferecendo às autoridades dados melhores para subsidiar as intervenções intersetoriais para o controle da leishmaniose cutânea.

5.
Mem Inst Oswaldo Cruz ; 115: e200220, 2020.
Article in English | MEDLINE | ID: mdl-32935751

ABSTRACT

BACKGROUND: The Nyssomyia genus and Lutzomyia subgenus include medical important species that are Latin American leishmaniases vectors. Little is known about the phylogenetic relationships of closely-related species in each of these taxonomic groups that are morphologically indistinguishable or differentiated by very subtle details. OBJECTIVES: We inferred the phylogenetic relationships of closely-related species within both the Nyssomyia genus and the Lutzomyia subgenus using a cytochrome c oxidase subunit I (COI) fragment. METHODS: The sampling was carried out from 11 Argentinean localities. For genetic analyses, we used GenBank sequences in addition to our sequences from Argentina. Kimura 2-parameter (K2P) genetic distance and nucleotide divergence (Da) was calculated between closely-related species of Nyssomyia genus, Lutzomyia subgenus and between clades of Lutzomyia longipalpis complex. FINDINGS: The K2P and Da values within species of Nyssomyia genus and Lutzomyia subgenus were lower than the divergence detected between clades of Lu. longipalpis complex. The haplotype network analyses within Lutzomyia subgenus showed shared haplotypes between species, contrary to Nyssomyia genus with none haplotype shared. Bayesian inference within Nyssomyia genus presented structuring by species. MAIN CONCLUSIONS: This study evidences the phylogenetic proximity among closely-related species within Nyssomyia genus and Lutzomyia subgenus. The COI sequences of Nyssomyia neivai derived from the present study are the first available in GenBank.


Subject(s)
Psychodidae/classification , Psychodidae/genetics , Animals , Argentina , Base Sequence , Bayes Theorem , Leishmaniasis , Phylogeny , Polymerase Chain Reaction/methods , Sequence Analysis, DNA/methods
6.
Parasitol Res ; 119(10): 3181-3201, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32803334

ABSTRACT

Giardia is a parasite distributed worldwide and one of the most prevalent intestinal protozoa in Argentina. We analysed all the national information regarding the prevalence of Giardia infections in humans, animals and environmental surveys over the last 40 years. In this work, we used Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and the period between 1980 and 2019 was defined as time lapse for inclusion of the studies. The analysis was conducted using the LILACS, PubMed, Scopus and Argentina SciELO databases employing as keywords 'Giardia' AND 'Argentina'. We also carried out a manual review of papers. Of 304 articles, 92 fitted the eligibility criteria. Giardia was reported in 15 of the 23 Argentine provinces; human prevalence was between 3.4 and 64.8%. Indigenous children and residents in peri-urban areas had the higher infection rates. In animals, Giardia was identified mainly in dogs with a prevalence of 8.9 ± 7.0%, and studies of wild animals and cattle were notably scarce. Environmental studies showed that Giardia was detected in the soil and water which may act as reservoirs for this parasite revealing the need to modify the national water treatment legislation. The identification of Giardia genetic assemblages in the studies analysed was limited and showed that genotypes AII and B were found in humans while assemblage B was mainly detected in animals. This report provides useful information on epidemiological aspects of giardiasis in Argentina that may help to define future research priorities and provides useful tools for professionals regarding actual information on the prevalence of this infection.


Subject(s)
Drinking Water/parasitology , Giardia lamblia/genetics , Giardia lamblia/isolation & purification , Giardiasis/epidemiology , Soil/parasitology , Adolescent , Animals , Animals, Wild/parasitology , Argentina/epidemiology , Cattle , Child , Child, Preschool , Dogs , Feces/parasitology , Female , Genotype , Humans , Indigenous Peoples/statistics & numerical data , Prevalence , Risk Factors , Surveys and Questionnaires , Water Purification
7.
Mem Inst Oswaldo Cruz ; 114: e190184, 2019.
Article in English | MEDLINE | ID: mdl-31576903

ABSTRACT

American visceral leishmaniasis (AVL) has two main scenarios of transmission as follows: scattered cases in rural areas and urban outbreaks. Urban AVL is in active dispersion from the northeastern border of Argentina-Paraguay-Brazil to the South. The presence of Lutzomyia longipalpis was initially reported in urban environments in the northwestern border of the country. The presence of Lu. longipalpis, environmental variables associated with its distribution, and its genetic diversity were assessed in Salvador Mazza, Argentina, on the border with Bolivia. The genetic analysis showed high haplotype diversity, low nucleotide diversity, and low nucleotide polymorphism index. We discuss the hypothesis of an expanding urban population with introgressive hybridisation of older haplogroups found in their path in natural forest or rural environments, acquiring a new adaptability to urban environments, and the possibility of changes in vector capacity.


Subject(s)
Animal Distribution , Genetic Variation/genetics , Insect Vectors/genetics , Psychodidae/genetics , Animals , Argentina , Bolivia , Brazil , DNA, Mitochondrial/genetics , Genes, Insect/genetics , Haplotypes , Insect Vectors/classification , Leishmaniasis, Cutaneous/transmission , Male , Phylogeography , Psychodidae/classification
8.
Mem Inst Oswaldo Cruz ; 112(10): 674-680, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28953995

ABSTRACT

BACKGROUND: Visceral leishmaniasis (VL) is an endemic disease in northeastern Argentina including the Corrientes province, where the presence of the vector and canine cases of VL were recently confirmed in December 2008. OBJECTIVES: The objective of this study was to assess the modelling of micro- and macro-habitat variables to evaluate the urban environmental suitability for the spatial distribution of Lutzomyia longipalpis presence and abundance in an urban scenario. METHODS: Sampling of 45 sites distributed throughout Corrientes city (Argentina) was carried out using REDILA-BL minilight traps in December 2013. The sampled specimens were identified according to methods described by Galati (2003). The analysis of variables derived from the processing of satellite images (macro-habitat variables) and from the entomological sampling and surveys (micro-habitat variables) was performed using the statistical software R. Three generalised linear models were constructed composed of micro- and macro-habitat variables to explain the spatial distribution of the abundance of Lu. longipalpis and one composed of micro-habitat variables to explain the occurrence of the vector. FINDINGS: A total of 609 phlebotominae belonging to five species were collected, of which 56% were Lu. longipalpis. In addition, the presence of Nyssomyia neivai and Migonemya migonei, which are vectors of tegumentary leishmaniasis, were also documented and represented 34.81% and 6.74% of the collections, respectively. The explanatory variable normalised difference vegetation index (NDVI) described the abundance distribution, whereas the presence of farmyard animals was important for explaining both the abundance and the occurrence of the vector. MAIN CONCLUSIONS: The results contribute to the identification of variables that can be used to establish priority areas for entomological surveillance and provide an efficient transfer tool for the control and prevention of vector-borne diseases.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Argentina , Ecosystem , Leishmaniasis, Visceral/transmission , Population Density , Spatial Analysis , Urban Population
9.
Am J Public Health ; 106(4): 720-6, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26890172

ABSTRACT

OBJECTIVES: To estimate trends of undernutrition (stunting and underweight) among children younger than 5 years covered by the universal health coverage programs Plan Nacer and Programa Sumar. METHODS: From 2005 to 2013, Plan Nacer and Programa Sumar collected high-quality information on birth and visit dates, age (in days), gender, weight (in kg), and height (in cm) for 1.4 million children in 6386 health centers (13 million records) with broad coverage of vulnerable populations in Argentina. RESULTS: The prevalence of stunting and underweight decreased 45.0% (from 20.6% to 11.3%) and 38.0% (from 4.0% to 2.5%), respectively, with differences between rural versus urban areas, gender, regions, age, and seasons. CONCLUSIONS: Undernutrition prevalence substantially decreased in 2 programs in Argentina as a result of universal health coverage.


Subject(s)
Child Development , Growth , Nutritional Status , Thinness/epidemiology , Universal Health Insurance , Argentina/epidemiology , Body Height , Child Nutrition Disorders/epidemiology , Child, Preschool , Female , Growth Disorders/epidemiology , Growth Disorders/therapy , Humans , Infant , Infant, Newborn , Male , Prevalence , Rural Population , Socioeconomic Factors , Urban Population , Vulnerable Populations
10.
Mem Inst Oswaldo Cruz ; 111(1): 75-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26814647

ABSTRACT

We report the presence of the competent vector for Leishmania spp, Migonemyia migonei, and the Evandromyia cortelezzii-sallesi complex south of its known distribution in the central temperate region of Argentina, in the province of Córdoba. The persistence of this phlebotomine in the northern border of the province, its association with a case of cutaneous leishmaniasis, and the new record in the outskirts of the city of Córdoba, the second most populated in the country, strengthens the need for regular vector surveillance and a case detection-sensitive health system in vulnerable regions, even in temperate climates.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Argentina , Climate , Female , Leishmaniasis, Cutaneous/transmission , Male , Seasons , Temperature
11.
Rev Panam Salud Publica ; 40(1): 29-39, 2016 Aug.
Article in Spanish | MEDLINE | ID: mdl-27706386

ABSTRACT

A retrospective analytical method is presented, based on theoretical eco-epidemiology, applied on a subnational spatial scale. This method was used here to describe scenarios for the transmission of leishmaniasis in the Argentine province of Misiones- bordering Brazil and Paraguay-and formed the basis for recommendations for surveillance and control appropriate to the subnational scale. An exhaustive search of the literature on leishmaniasis in the province was carried out. Three scenarios for the transmission of cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL) were found, corresponding to three periods: from 1920 to 1997, during which the transmission of CL distributed over time and space was confirmed; 1998 to 2005, during which there were focal outbreaks of CL; and 2006 to 2014, during which outbreaks were also reported and the geographical dispersion of VL was documented. To describe the risk scenarios and the anthropic processes that produce them, the results were summarized and integrated into the social, historical, and bio-ecological context of each period. Surveillance and control recommendations are based on the territory studied. They include establishing active surveillance to monitor possible rising trends in parasitic and vector circulation, conducting studies of any focal outbreak in order to confirm indigenous transmission and severity. Also, it should be a legal requirement for persons responsible for projects that alter the environment to adopt additional control measures, such as studies assessing transmission risk, risk mitigation, early detection, and timely case management.


Subject(s)
Insect Vectors , Leishmaniasis, Cutaneous/transmission , Leishmaniasis, Visceral/transmission , Population Surveillance/methods , Animals , Argentina/epidemiology , Disease Outbreaks , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Visceral/epidemiology , Psychodidae , Retrospective Studies , Time Factors
12.
Mem Inst Oswaldo Cruz ; 110(7): 831-46, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26517497

ABSTRACT

Since the description of Lutzomyia longipalpis by Lutz and Neiva more than 100 years ago, much has been written in the scientific literature about this phlebotomine species. Soares and Turco (2003) and Lainson and Rangel (2005) have written extensive reviews focused on vector-host-parasite interactions and American visceral leishmaniasis ecology. However, during the last two decades, the success of Lu. longipalpis in colonising urban environments and its simultaneous geographical spreading have led to new theoretical and operational questions. Therefore, this review updates the general information about this species and notes the more challenging topics regarding the new scenario of urbanisation-spreading and its control in America. Here, we summarise the literature on these issues and the remaining unsolved questions, which pose recommendations for operational research.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Insect Control , Latin America , Leishmaniasis, Cutaneous/transmission , Leishmaniasis, Visceral/transmission , Urbanization
13.
Mem Inst Oswaldo Cruz ; 109(4): 488-91, 2014 Jul.
Article in English | MEDLINE | ID: mdl-25075787

ABSTRACT

Lutzomyia longipalpis was recorded for the first time in Argentina in 2004, in the province of Formosa. In the following years, the vector spread to the south and west in the country and was recorded in the province of Chaco in 2010. From November 2010-May 2012, captures of Phlebotominae were made in the city of Resistencia and its surroundings, to monitor the spread and possible colonisation of Lu. longipalpis in the province of Chaco. In this monitoring, Lu. longipalpis was absent in urban sampling sites and its presence was restricted to Barrio de los Pescadores. This suggests that the incipient colonisation observed in 2010 was not followed by continuous installation of vector populations and expansion of their spatial distribution as in other urban centres of Argentina.


Subject(s)
Insect Vectors , Psychodidae , Animals , Argentina , Insect Vectors/classification , Leishmaniasis, Visceral/transmission , Population Density , Psychodidae/classification , Seasons , Urban Population
14.
Neotrop Entomol ; 53(1): 47-55, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37973714

ABSTRACT

Migonemyia migonei (FranÒ«a, 1920) (Diptera: Psychodidae) belongs to the subfamily Phlebotominae, of epidemiological importance due to its role as a vector in leishmaniasis transmission cycles and its broad geographic distribution in South America. Few morphometric and genetic studies have demonstrated the existence of variability among geographically distant populations in Brazil. The aim of the study was to estimate the genetic distance within the morphospecies Mg. migonei through the analysis of cytochrome C oxidase subunit I (COI) sequences of specimens captured in Argentina and those available in online databases. The COI sequences from specimens collected in different localities of Argentina and sequences available in online databases were utilized. Genetic distances were analyzed and a median-joining haplotype network was constructed. Finally, phylogenetic reconstruction was performed according to Bayesian inference. The analyses led to the identification of at least two haplogroups: haplogroup I with sequences of specimens from Colombia, Brazil and Argentina, and haplogroup II with sequences of specimens from Argentina. Interestingly, specimens from Argentina whose haplotypes corresponded to both haplogroups, were collected in sympatry. The results suggest that Mg. migonei could be a species complex with at least two distinct members. This hypothesis could explain the known characteristics of adaptability and vector permissiveness of the species, as the putative cryptic species of the complex could differ in traits of epidemiological importance.


Subject(s)
Leishmaniasis , Psychodidae , Animals , Phylogeny , Bayes Theorem , Sympatry , Brazil
15.
Zoonoses Public Health ; 71(3): 267-273, 2024 May.
Article in English | MEDLINE | ID: mdl-38336960

ABSTRACT

American cutaneous leishmaniasis (ACL) is the most prevalent form of leishmaniasis, associated with an ulcerative and stigmatizing mucocutaneous pathology. This study assessed the incidence of Leishmania (Viannia) braziliensis in members of the Argentine Army who were exposed to sandfly bites in Iguazú National Park (INP), northeastern Argentina, during an outbreak of ACL in 2019, and the presence of Leishmania in rodents, opossums and phlebotomine sandflies collected in the area of exposure. Samples from military personnel, wild animals and phlebotomine sandflies were analysed. A total of 20 (40%) patients among the Army personnel and two Akodon montensis rodents (11%) were positive for the presence of Leishmania sp. genes by PCR, while Nyssomyia whitmani and Migonemyia migonei, competent vectors of Leishmania, were also found at the same site. Sequences of hsp70 DNA fragments obtained from human samples confirmed the identity of L. (V.) braziliensis. The risk to which military personnel carrying out activities in the forest are exposed is highlighted, and this risk extends to any worker and visitor who circulates without protection in the INP, coming into contact with transmission "hot spots" due to the concentration of vectors, reservoirs and/or parasites.


Subject(s)
Leishmania braziliensis , Leishmania , Leishmaniasis, Cutaneous , Leishmaniasis , Psychodidae , Humans , Animals , Argentina/epidemiology , Insect Vectors/parasitology , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/veterinary , Leishmaniasis, Cutaneous/parasitology , Leishmania/genetics , Leishmania braziliensis/genetics , Psychodidae/parasitology , Forests , Brazil/epidemiology , Leishmaniasis/veterinary
16.
Mem Inst Oswaldo Cruz ; 108(8): 1071-3, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24402160

ABSTRACT

In 2004, the urban presence of Lutzomyia longipalpis was recorded for the first time in Formosa province. In 2006, the first autochthonous case of human urban visceral leishmaniasis (VL) was recorded in Misiones in the presence of the vector, along with some canine VL cases. After this first case, the vector began to spread primarily in northeast Argentina. Between 2008-2011, three human VL cases were reported in Salta province, but the presence of Lu. longipalpis was not recorded. Captures of Phlebotominae were made in Tartagal, Salta, in 2013, and the presence of Lu. longipalpis was first recorded in northwest Argentina at that time. Systematic sampling is recommended to observe the distribution and dispersion patterns of Lu. longipalpis and consider the risk of VL transmission in the region.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Argentina , Dogs , Humans , Leishmaniasis, Visceral/transmission , Urban Population
17.
Mem Inst Oswaldo Cruz ; 108(7): 817-24, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24271040

ABSTRACT

This study aimed to analyse changes in the spatial distribution of Lutzomyia longipalpis in Posadas, an urban area located in northeastern Argentina. Data were obtained during the summer of 2007 and 2009 through two entomological surveys of peridomiciles distributed around the city. The abundance distribution pattern for 2009 was computed and compared with the previous pattern obtained in 2007, when the first human visceral leishmaniasis cases were reported in the city. Vector abundance was also examined in relation to micro and macrohabitat characteristics. In 2007 and 2009, Lu. longipalpis was distributed among 41.5% and 31% of the households in the study area, respectively. In both years, the abundance rates at most of the trapping sites were below 30 Lu. longipalpis per trap per night; however, for areas exhibiting 30-60 Lu. longipalpis and more than 60 Lu. longipalpis, the areas increased in both size and number from 2007-2009. Lu. longipalpis was more abundant in areas with a higher tree and bush cover (a macrohabitat characteristic) and in peridomiciles with accumulated unused material (a microhabitat characteristic). These results will help to prioritise and focus control efforts by defining which peridomiciles display a potentially high abundance of Lu. longipalpis.


Subject(s)
Insect Vectors/classification , Leishmania infantum , Psychodidae/classification , Animals , Argentina , Female , Humans , Leishmaniasis, Visceral/transmission , Male , Population Density , Seasons , Urban Population
18.
Zootaxa ; 5264(4): 579-586, 2023 Apr 17.
Article in English | MEDLINE | ID: mdl-37518030

ABSTRACT

The degree of host specificity of fleas varies from highly specific (monoxenous) to opportunistic (polyxenous). Specific parasite-host associations can be observed among some flea families and tribes and mammalian orders, such as fleas of the tribe Tritopsyllini (Ctenophthalmidae, Doratopsyllinae) and opossums (Didelphimorphia). Specimens of the family Didelphidae are common hosts of fleas of the genus Adoratopsylla (Ewing, 1925). In northern Argentina, Adoratopsylla (Adoratopsylla) antiquorum antiquorum (Rothschild, 1904) and Adoratopsylla (Tritopsylla) intermedia intermedia (Wagner, 1901) were recorded preferentially parasitizing opossums. In order to study parasite/host relationships, fleas were collected from opossums captured in different environments in the Paranaense Rainforest ecoregion, northern Misiones province between 2016 and 2018. A total of 287 fleas were collected from 110 opossums. The fleas were identified as Pulicidae: Ctenocephalides felis felis (Bouché, 1835); Rhopalopsyllidae: Polygenis (Polygenis) rimatus (Jordan, 1932), Polygenis (Polygenis) roberti roberti (Rothschild, 1905); Ctenophthalmidae: A. (T.) i. intermedia, A. (A.) a. antiquorum, Adoratopsylla (Adoratopsylla) antiquorum ronnai (Guimarães, 1954). We report for the first time in Argentina a male specimen of A. (A.) a. ronnai collected on Didelphis albiventris (Lund, 1840) (Didelphidae), and male and female specimens of P. (P.) r. roberti collected on Didelphis aurita (Wied-Neuwied, 1826), and we describe the expansion of the geographic and host distribution of fleas to the Paranaense Rainforest ecoregion. Our records reinforce the specific association between Adoratopsylla and Polygenis fleas and didelphid opossums, mentioned in the literature for the Atlantic Forest ecoregion in Brazil. Furthermore, we observed that flea communities in opossums change in a landscape gradient, with invasive cat fleas and euryxenous fleas common in anthropized areas, and endemic fleas common in natural areas. Our results underline the importance for public health and veterinary medicine the analysis of flea circulation between wild and urban environments due to the risk of pathogen transmission.


Subject(s)
Didelphis , Flea Infestations , Marsupialia , Siphonaptera , Male , Female , Animals , Rainforest , Flea Infestations/veterinary , Flea Infestations/epidemiology , Mammals
19.
J Med Entomol ; 60(5): 1088-1098, 2023 09 12.
Article in English | MEDLINE | ID: mdl-37313956

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.


Subject(s)
Leishmaniasis, Cutaneous , Leishmaniasis , Psychodidae , Humans , Animals , Argentina , Leishmaniasis/epidemiology , South America , Population Dynamics , Brazil/epidemiology , Leishmaniasis, Cutaneous/epidemiology
20.
Mem Inst Oswaldo Cruz ; 107(4): 550-2, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22666869

ABSTRACT

The aim of this work was to identify the natural breeding sites of sandflies in the province of Chaco, Argentina, for the first time. Preliminary studies were conducted in two different phytogeographic regions: dry Chaco (Parque Provincial Pampa del Indio), in January 2010, and humid Chaco (Resistencia, Margarita Belén and Colonia Benítez), from May-September 2010. A total of 127 samples were collected (Pampa del Indio: 15, Resistencia: 37, Margarita Belén: 36, Colonia Benítez: 39). A female of Migonemyia migonei was found in Pampa del Indio at the base of a bromeliad in the summer (January) and a pupal exuvium of a phlebotomine fly was found in Resistencia, in a place where dogs rested, in the winter (July). These findings highlighted these two sites as potential breeding sites. Because the existence of potential natural breeding sites for sandflies has been demonstrated in both forest and periurban areas, expanding the search efforts and characterising these sites will enable the development of specific study designs to gain insight into the spatial distribution of the risks posed by these vectors. The resulting information will serve as a basis for proposing and evaluating vector control measures.


Subject(s)
Ecosystem , Insect Vectors/physiology , Psychodidae/physiology , Animals , Argentina , Dogs , Female , Insect Vectors/classification , Leishmaniasis/transmission , Psychodidae/classification , Reproduction , Seasons
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