Deforestation increases the abundance of rodents and their ectoparasites in the Lacandon forest, Southern Mexico

Introduction: Tropical forests provide important ecosystem services, including disease control. However, few studies have focused on how deforestation affects species more suitable to be zoonotic vectors. Objective: To evaluate how deforestation affects the abundance and species richness of rodents and their associated ectoparasites in a tropical ecosystem. Methods: We captured rodents in 6 landscape units, 1 km² each, with 0.7; 5; 40; 46; 78 and 95 % tree cover, in Marques de Comillas, Chiapas, Southern Mexico. In each unit we set 90 Sherman traps that were active 24 hours for 7 days during two sampling seasons (October 2019, and September 2020). We manually extracted ectoparasites from all captured rodents. Results: We captured 70 rodents of five species: Sigmodon toltecus, Heteromys desmarestianus, Ototylomys phyllotis, Peromyscus mexicanus, and Oryzomys couesi. Rodent abundance increased with forest loss (R²= 0.706, P= 0.022). The greatest richness of rodent species occurred in sites with intermediate forest cover (40 and 78 %). The most abundant species were: S. toltecus (N= 45) followed by O. couesi (N= 9), these species dominated in sites with less forest cover. We recorded a total of 23 ectoparasite species, three of them known to be zoonotic vectors: Amblyomma sp., Ornithonyssus bacoti, and Androlaelaps fahrenholzi. Conclusions: The ongoing loss of forests promotes the proliferation of zoonotic disease vectors in this tropical ecosystem, which can potentially increase the frequency of affectation among the local population.

Introducción: Un servicio particularmente importante que brindan los bosques tropicales es el control de enfermedades. Sin embargo, pocos estudios se han enfocado en analizar cómo este servicio es afectado por la deforestación. Objetivo: Evaluar el efecto de la deforestación en la abundancia y riqueza de especies de roedores y de sus ectoparásitos en Marqués de Comillas, en el sureste de México. Métodos: Capturamos roedores en 6 unidades del paisaje (UP), cada una de 1 km², con distintos porcentajes de cobertura vegetal (0.7, 5, 40, 46, 78 y 95 %). En cada UP colocamos 90 trampas Sherman, que permanecieron activas las 24 horas por 7 días durante dos muestreos en octubre 2019 y septiembre 2020. Todos los roedores capturados fueron revisados para detectar ectoparásitos en su pelaje que fueron recolectados para su posterior identificación en el laboratorio. Resultados: Capturamos 70 roedores de cinco especies: Sigmodon toltecus, Heteromys desmarestianus, Ototylomys phyllotis, Peromyscus mexicanus y Oryzomys couesi. La abundancia de roedores aumentó con la pérdida de bosque (R² = 0.706, P = 0.022). La mayor riqueza de especies de roedores se presentó en sitios con cobertura forestal intermedia (40 y 78 %). Las especies más abundantes fueron: S. toltecus (N = 45) seguido de O. couesi (N = 9), estas especies dominaron en los sitios con menor cobertura forestal. Registramos un total de 23 ectoparásitos diferentes, identificamos 15 a nivel de especie y ocho a nivel de género. Los sitios con menor cobertura forestal presentaron la menor riqueza de especies de ectoparásitos. Detectamos tres especies de ectoparásitos (Amblyomma sp., Ornithonyssus bacoti y Androlaelaps fahrenholzi) que se sabe que son vectores de enfermedades zoonóticas. Conclusión: Encontramos que la deforestación está promoviendo un aumento en la proliferación de vectores de enfermedades zoonóticas lo que, a su vez, tiene el potencial de incrementar las afectaciones de la población local.

Oral mite anaphylaxis (pancake syndrome) in Peru: an underestimated problem? / Anafilaxia por ingesta de ácaros (Síndrome da panqueca) no Peru: um problema subestimado?

Sabe-se que a urticária e o angioedema apresentam diferentes etiologias, pois podem ser de natureza alérgica, infecciosa, autoimune ou espontânea. Em episódios únicos ou recorrentes, deve-se considerar um alérgeno desencadeante oculto, como os ácaros de poeira doméstica (APDs). Vários relatos demonstraram que farinhas contaminadas com APDs podem causar urticária e angioedema, incluindo reações alérgicas graves com risco de vida quando ingeridos em grandes quantidades provenientes de farinha de trigo armazenada. Neste estudo, relatamos os achados clínicos de 31 pacientes, incluindo casos de anafilaxia após ingestão de farinha contaminada com ácaros. Também encontramos uma relação entre uma história clínica de hipersensibilidade a anti-inflamatórios não esteroides e síndrome de anafilaxia por ingesta de ácaros em pacientes atópicos, consistente com a teoria de uma "nova tríade do ácido acetilsalicílico", conforme publicado anteriormente, e agora sendo descrito pela primeira vez no Peru.

Urticaria and angioedema are known to have different etiologies, as they can be allergic, infectious, autoimmune, or spontaneous in nature. In single or recurrent episodes, a hidden triggering allergen should be considered, such as house dust mites (HDMs). Several reports have demonstrated that flours contaminated with HDMs can cause urticaria and angioedema, including severe lifethreatening allergic reactions when ingested in large quantities from stored wheat flour. In this study, we report the clinical findings in 31 patients, including cases of anaphylaxis after the ingestion of mite-contaminated flour. We also found a relationship between a clinical history of hypersensitivity to nonsteroidal anti-inflammatory drugs and oral mite anaphylaxis syndrome in atopic patients, consistent with the theory of a "new aspirin triad," as previously published, and now being described for the first time in Peru.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan / Prevalência e diversidade de ectoparasitas em Wild Rock Pigeon (Columba livia) na região de Punjab, Paquistão

Abstract The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P < 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

Resumo O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P <0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan / Prevalência e diversidade de ectoparasitas em Wild Rock Pigeon (Columba livia) na região de Punjab, Paquistão

The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P < 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P <0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Side effects of abamectin and hexythiazox on seven predatory mites / Efeitos colaterais da abamectina e hexitiazox em sete ácaros predadores

Use of acaricides has become a common practice to control pests all over the world including Saudi Arabia. In spite of killing the targeted pests, such insecticides also effect growth of predatory mites. Present study has been conducted to evaluate the impact of two acaricides, abamectin and hexythiazox, on seven species of predatory mites. Standard solutions of abamectin (8.4% w/v) and hexythiazox (10% w/w) were purchased and prepared for direct spray. Acaricides were tested at three serial concentrations of recommended dose (RD), half of the recommended dose (HRD) and double the recommended dose (DRD). Trials were made on eggs, nymphs and adults of the seven species of predatory mites under laboratory conditions. Effect of the applied acaricides was determined one week after the application. The results of the study revealed that all doses of hexythiazox and abamectin are toxic to the nymphs and adults of all seven species of predatory mites but to the variable extent. Furthermore, it was observed that hexythiazox and abamectin reduced the percentage of egg hatching for all seven species of predatory mites. Hexythiazox was found to be more toxic than abamectin to all seven predatory mites. Higher mortality was recorded at DRD and RD, while minimum mortality was recorded at HRD. Acaricidal effect is less severe on hatching eggs than on immatures and adults of the predatory mites. Species vary in susceptibility to acaricides and in some populations resistance has been observed. Based upon this study, it is recommended that the frequent use of acaricides against phytophagous mites should be avoided and feasibility of biological control programs should be promoted to protect the environment, health of living individuals and the non-target organisms.

O uso de acaricidas se tornou prática comum para o controle de pragas em todo o mundo, incluindo a Arábia Saudita. Apesar de matar as pragas-alvo, esses inseticidas também afetam o crescimento de ácaros predadores. O presente estudo foi conduzido para avaliar o impacto de dois acaricidas, abamectina e hexythiazox, em sete espécies de ácaros predadores. Soluções padrão de abamectina (8.4% w/v) e hexitiazox (10% w/w) foram adquiridas e preparadas para pulverização direta. Os acaricidas foram testados em três concentrações seriais de dose recomendada (RD), metade da dose recomendada (HRD) e o dobro da dose recomendada (DRD). Os ensaios foram feitos em ovos, ninfas e adultos das sete espécies de ácaros predadores em condições de laboratório. O efeito dos acaricidas aplicados foi determinado uma semana após a aplicação. Os resultados do estudo revelaram que todas as doses de hexitiazox e abamectina são tóxicas para as ninfas e adultos de todas as sete espécies de ácaros predadores, mas em extensão variável. Além disso, foi observado que hexitiazox e abamectina reduziram a porcentagem de eclosão de ovos para todas as sete espécies de ácaros predadores. Verificou-se que o hexitiazox é mais tóxico do que a abamectinapara todos os sete ácaros predadores. A mortalidade mais alta foi registrada no DRD e RD, enquanto a mortalidade mínima foi registrada no HRD. O efeito acaricida é menos severo em ovos para incubação do que em imaturos e adultos de ácaros predadores. As espécies variam em suscetibilidade a acaricidas, e em algumas populações foi observada resistência. Com base neste estudo, recomenda-se que o uso frequente de acaricidas contra ácaros fitófagos seja evitado e a viabilidade de programas de controle biológico seja promovida para proteger o meio ambiente, a saúde de indivíduos vivos e de organismos não visados.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan

Abstract The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

Resumo O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P 0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Side effects of abamectin and hexythiazox on seven predatory mites

Abstract Use of acaricides has become a common practice to control pests all over the world including Saudi Arabia. In spite of killing the targeted pests, such insecticides also effect growth of predatory mites. Present study has been conducted to evaluate the impact of two acaricides, abamectin and hexythiazox, on seven species of predatory mites. Standard solutions of abamectin (8.4% w/v) and hexythiazox (10% w/w) were purchased and prepared for direct spray. Acaricides were tested at three serial concentrations of recommended dose (RD), half of the recommended dose (HRD) and double the recommended dose (DRD). Trials were made on eggs, nymphs and adults of the seven species of predatory mites under laboratory conditions. Effect of the applied acaricides was determined one week after the application. The results of the study revealed that all doses of hexythiazox and abamectin are toxic to the nymphs and adults of all seven species of predatory mites but to the variable extent. Furthermore, it was observed that hexythiazox and abamectin reduced the percentage of egg hatching for all seven species of predatory mites. Hexythiazox was found to be more toxic than abamectin to all seven predatory mites. Higher mortality was recorded at DRD and RD, while minimum mortality was recorded at HRD. Acaricidal effect is less severe on hatching eggs than on immatures and adults of the predatory mites. Species vary in susceptibility to acaricides and in some populations resistance has been observed. Based upon this study, it is recommended that the frequent use of acaricides against phytophagous mites should be avoided and feasibility of biological control programs should be promoted to protect the environment, health of living individuals and the non-target organisms.

Resumo O uso de acaricidas se tornou prática comum para o controle de pragas em todo o mundo, incluindo a Arábia Saudita. Apesar de matar as pragas-alvo, esses inseticidas também afetam o crescimento de ácaros predadores. O presente estudo foi conduzido para avaliar o impacto de dois acaricidas, abamectina e hexythiazox, em sete espécies de ácaros predadores. Soluções padrão de abamectina (8.4% w/v) e hexitiazox (10% w/w) foram adquiridas e preparadas para pulverização direta. Os acaricidas foram testados em três concentrações seriais de dose recomendada (RD), metade da dose recomendada (HRD) e o dobro da dose recomendada (DRD). Os ensaios foram feitos em ovos, ninfas e adultos das sete espécies de ácaros predadores em condições de laboratório. O efeito dos acaricidas aplicados foi determinado uma semana após a aplicação. Os resultados do estudo revelaram que todas as doses de hexitiazox e abamectina são tóxicas para as ninfas e adultos de todas as sete espécies de ácaros predadores, mas em extensão variável. Além disso, foi observado que hexitiazox e abamectina reduziram a porcentagem de eclosão de ovos para todas as sete espécies de ácaros predadores. Verificou-se que o hexitiazox é mais tóxico do que a abamectina para todos os sete ácaros predadores. A mortalidade mais alta foi registrada no DRD e RD, enquanto a mortalidade mínima foi registrada no HRD. O efeito acaricida é menos severo em ovos para incubação do que em imaturos e adultos de ácaros predadores. As espécies variam em suscetibilidade a acaricidas, e em algumas populações foi observada resistência. Com base neste estudo, recomenda-se que o uso frequente de acaricidas contra ácaros fitófagos seja evitado e a viabilidade de programas de controle biológico seja promovida para proteger o meio ambiente, a saúde de indivíduos vivos e de organismos não visados.

Fauna of scrub typhus vector chigger mites in Yunnan Province / 中国热带医学

@#Abstract: Chigger mites belong to the phylum Arthropoda, class Arachnida, sub-class Acari, order Parasitiformes, family Trombiculidae and Leeuwenhoekiidae, with a wide range of species. There are more than 3 700 known species of mites globally, of which 531 species in 46 genera from three sub-families have been recorded in China, and 320 species of chigger mites recorded from 3 subfamilies and 32 genera in Yunnan Province. At this stage, chigger mites are the only vectors of scrub typhus, with about 60 species worldwide being potential vectors. Six vectorial mite species have been confirmed in China, including Leptotrombidium deliense, L.scutellare, L.rubellum, L.sialkotense, L.kaohuense, L.insulare. Yunnan Province has reported five vectorial mite species, including the previously-mentioned five species except for L.sialkotense. The zoogeographic study divided Yunnan Province into 5 zoogeographic areas, namely, Central Hengduan Mountains subregion, Southern Hengduan Mountains subregion, Eastern Yunnan Plateau subregion, Western Yunnan Plateau subregion, Southern Yunnan Mountainous subregion. The Southern Hengduan Mountains subregion has the highest number of known genera and species of scrub typhus and the highest number of scrub typhus cases, with 216 species in 22 genera from 3 subfamilies, and all 5 species of vector scrub typhus were distributed. Southern Yunnan Mountain subregion has the least number of mite species, with 91 species in 12 genera from three sub-families, with L. scutellare being the dominant vectorial mite species across the province. Due to suitable natural geographic conditions in Yunnan Province, vectorial mites can propagate rapidly, leading to a large number of scrub typhus cases. According to statistics, the number of scrub typhus cases in Yunnan Province has rapidly increased, with 15.40 times, 20.64 times and 28.91 times more cases in 2016, 2017 and 2018 respectively than in 2006. Scrub typhus remains a serious public health problem in Yunnan Province, posing a threat to the health of the local population. Therefore, prevention and control efforts should continue to focus on the affected areas and the general public.

Rinitis alérgica, apnea-hipopnea obstructiva del sueño y sensibilización a ácaros / Allergic rhinitis, obstructive sleep apnea-hypopnea and mite sensitization

La asociación de rinitis alérgica y el síndrome de apnea-hipopnea obstructiva del sueño se presenta en diferentes edades. En la rinitis alérgica y el síndrome de apnea-hipopnea obstructiva del sueño, puede estar involucrada la sensibilización a ácaros, principalmente: Dermatophagoides pteronyssinus, Dermatophagoides siboney y Blomia tropicalis. Con el objetivo de diagnosticar el síndrome de apnea-hipopnea obstructiva del sueño se seleccionaron 120 individuos del registro de alergia del Policlínico Previsora, Camagüey, Cuba, con diagnóstico presuntivo de rinitis alérgica y edad entre 5 y 15 años cumplidos. Todos tenían realizada la prueba de punción cutánea con Dermatophagoides pteronyssinus, Dermatophagoides siboney y Blomia tropicalis; algunos también, la poligrafía cardiorrespiratoria mediante el dispositivo ApneaLinkAirTM (Resmed Corp., RFA), utilizando el marcaje automático de eventos. La muestra fue de 40 casos (respiración oral, ronquidos) y 80 controles (sin respiración oral, ni ronquidos). La media del tamaño del habón fue de 7,9 mm en los casos y 4,1 mm en los controles (p꞊0,030). El índice de apnea-hipopnea fue positivo en 47 (39,1 por ciento) pacientes, de ellos, 36 (30 por ciento) casos y 11 (9,1 por ciento) controles (p=0,001). La sensibilidad y especificidad de la poligrafía cardiorrespiratoria mostró valores de 85,00 por ciento y 91,25 por ciento respectivamente que permiten afirmar el grado de eficacia de la prueba para diagnosticar apnea e hipopnea obstructiva del sueño. Los pacientes con síndrome de apnea-hipopnea obstructiva del sueño en los casos y controles presentaron incremento, con predominio para casos. La poligrafía cardiorrespiratoria con el dispositivo ApneaLink permite hacer el diagnóstico del síndrome de apnea-hipopnea obstructiva del sueño en rinitis alérgica(AU)

The association of allergic rhinitis and obstructive sleep apnea-hypopnea syndrome occurs at different ages. In allergic rhinitis and obstructive sleep apnea-hypopnea syndrome, sensitization to mites may be involved, mainly: Dermatophagoides pteronyssinus, Dermatophagoides siboney and Blomia tropicalis. With the objective to diagnose obstructive sleep apnea-hypopnea syndrome, 120 individuals were selected from the allergy registry of the Previsora Polyclinic, Camagüey, Cuba, with a presumptive diagnosis of allergic rhinitis and ages between 5 and 15 years old. All had the skin prick test with Dermatophagoides pteronyssinus, Dermatophagoides siboney and Blomia tropicalis; some also, cardio-respiratory polygraphy with the ApneaLink AirTM device (Resmed Corp., RFA), using automatic event marking. The sample consisted of 40 cases (oral breathing, snoring) and 80 controls (no oral breathing or snoring). The mean size of the wheal was 7.9 mm in the cases and 4.1 mm in the controls (p꞊0.030). The apnea and hypopnea index was positive in 47 (39.1 percent) patients, of which 36 (30 percent) were cases and 11 (9.1 percent) were controls (p=0.001). The sensitivity and specificity of the cardiorespiratory polygraphy showed values of 85.00 percent and 91.25 percent, respectively, which allow affirming the degree of efficacy of the test to diagnose obstructive sleep apnea-hypopnea. Patients with obstructive sleep apnea-hypopnea syndrome in cases and controls presented an increase, with a predominance for cases. Cardiorespiratory polygraphy with the ApneaLink device allows the diagnosis of obstructive sleep apnea-hypopnea syndrome in allergic rhinitis(AU)

Rinite alérgica persistente com elevada sensibilização a pólen de gramíneas: a medicina personalizada pode identificar os verdadeiros alérgicos a polens na imunoterapia / Persistent allergic rhinitis with high sensitization to grass pollen: personalized medicine can identify immunotherapy patients who are truly allergic to pollen

Este trabalho teve como objetivo avaliar pacientes com rinite alérgica persistente, sensibilizados a ácaros domésticos, associado à elevada sensibilização por pólen de gramíneas, sem sintomatologia estacional. Usou-se como método o diagnóstico molecular por componentes para selecionar os verdadeiramente alérgicos ao pólen de gramíneas. Foi realizado um estudo retrospectivo com análise de prontuários de pacientes em áreas de Caxias do Sul e municípios próximos no estado do RS, nos anos de 2016 e 2017, com as mesmas características climáticas. Foram selecionados 50 pacientes com alergia a ácaros, através de teste de punctura (pápula > 5 mm) associado ao pólen de gramíneas (pápula de > 7 mm) sem sintomatologia na primavera. Um total de 52% era do sexo feminino, a idade variou entre 4 e 56 anos, com uma média de 26,6 anos. Pesquisou-se a dosagem de IgE específica no soro para antígenos moleculares de pólen de gramíneas como estes: Phl p1, Phl p5, Cyn d1, em todos os pacientes. Houve 13 pacientes (26%) com diagnóstico, pelo menos, a um dos antígenos moleculares estudados. A amostra restringida apresentou 5 (10%) deles que possuíam Phl p5 > Phl p1, ou seja, eram verdadeiramente alérgicos à subfamília Poideae, enquanto 2 (4%) apresentaram Cyn d1 (subfamília Chloridoideae) > Phl p1. O estudo mostra que, em pacientes com rinite alérgica persistente, polissensibilizados a ácaros associados a pólen de gramíneas, sem sintomas estacionais característicos, os testes moleculares podem diagnosticar os verdadeiros alérgicos ao pólen.

This study aimed to evaluate patients with persistent allergic rhinitis who are sensitized to house mites and have high sensitization to grass pollen without seasonal symptoms. Molecular diagnosis was used to determine patients truly allergic to grass pollen. This retrospective study analyzed the medical records of patients from areas of Caxias do Sul and nearby municipalities (all with the same climatic characteristics) in the state of Rio Grande do Sul, Brazil between 2016 and 2017. Fifty patients allergic to dust mites were selected through a prick test (papule > 5 mm) and grass pollen (papule > 7 mm), but were asymptomatic in the spring. A total of 52% were female, and their ages ranged from 4 to 56 (mean 26.6) years. Specific serum IgE levels for grass pollen antigens, such as Phl p1, Phl p5, and Cyn d1, were investigated in all patients. Thirteen patients (26%) were diagnosed with at least one studied molecular antigen. The restricted sample included 5 (10%) patients with Phl p5 > Phl p1, ie, truly allergic to the Pooideae subfamily, while 2 (4%) had Cyn d1 (Chloridoideae subfamily) > Phl p1. The results indicate that among patients with persistent allergic rhinitis polysensitized to mites and grass pollen but without characteristic seasonal symptoms, molecular tests can diagnose those who are truly allergic to pollen.

Associations between house dust mites and prevalence of asthma and allergic rhinitis among school-age adolescents in the south of Brazil / Associações entre ácaros da poeira domiciliar e prevalência de asma e rinite alérgica em adolescentes em idade escolar no sul do Brasil

Background: Allergic reactions resulting from exposure to environmental allergens are responsible for problems such as asthma and allergic rhinitis. House dust mites (HDMs) are one of the most important causes of allergic sensitization and a major source of allergens worldwide. Objective: To investigate associations between the presence of HDMs in the homes of adolescents aged 13 to 14 years and the prevalence of respiratory problems using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Methods: A total of 103 adolescents from the city of Lajeado, south of Brazil, participated in the ISAAC Protocol, and 10 homes were sampled for dust collection. Results: Regarding the medical history of asthma and rhinitis, a prevalence of 14.7% of asthma was found, and 68.9% of the adolescents have already had rhinitis. The investigation of active asthma and rhinitis showed that 5.15% of adolescents had symptoms of asthma and 39.14% had symptoms of allergic rhinitis. Premature birth, low birth weight and smoking mother were shown to be risk factors for the development of asthma and allergic rhinitis. HDMs were mostly found on the carpet (46.80%), followed by bed (34.04%) and sofa (14.89%); curtains had the fewest mites (4.25%). Dermatophagoides pteronyssinus (46.0%) and Dermatophagoides farinae (31.91%) were the most frequently found species. Conclusion: The homes of adolescents with respiratory problems had a large number of HDMs.

Introdução: As reações alérgicas resultantes da exposição a alérgenos ambientais são responsáveis por problemas como asma e rinite alérgica. Os ácaros conhecidos como ácaros da poeira domiciliar (HDMs) são uma das causas mais importantes de sensibilização alérgica e representam uma das fontes de alérgenos mais importantes do mundo. Objetivo: O presente estudo tenta encontrar uma relação entre a presença de HDMs nas residências de adolescentes de 13 a 14 anos e a prevalência de problemas respiratórios, usando o questionário ISAAC (International Study of Asthma and Allergies in Childhood). Método: Participaram do Protocolo ISAAC 103 adolescentes da cidade de Lajeado (RS), dez domicílios foram amostrados para coleta de poeira. Resultados: Em relação à história clínica de asma e rinite, foi encontrada prevalência de 14,7% de asma, sendo que 68,9% dos adolescentes já apresentaram rinite. A investigação de asma e rinite ativa mostrou que 5,15% dos adolescentes apresentaram sintomas de asma e 39,14% apresentaram sintomas de rinite alérgica. Nascimento prematuro, baixo peso ao nascer e mãe fumante demonstraram ser fatores de risco para o desenvolvimento de asma e rinite alérgica. O local onde foi encontrado o maior número de ácaros foi tapete (46,80%), seguido de cama (34,04%), sofá (14,89%); cortina foi o local com menor número de ácaros encontrados (4,25%). Dermatophagoides pteronyssinus (46,0%) e Dermatophagoides farinae (31,91%) foram as espécies mais encontradas na poeira. Conclusão: As residências de adolescentes com problemas respiratórios apresentaram um maior número de HDMs.

Some Mites Occurring On Edible And Wild Mushrooms From Three Districts Of West Bengal With Their Economic Importance

The present paper reports occurrence of 15 species of mites under 10 families and 12 genera collected from edible and wild mushrooms from three districts of West Bengal during, September 2021 to April 2022. Among the mites, there were 9 predatory and 3 each of damage causing and of uncertain association. All the species have been listed giving collection data and remarks pertaining to their importance as damage causing, predatory, or of uncertain association. The mites like Tyrophagus putrescentiae, Fuscuropoda marginata and Leiodinychus krameri were abundantly encountered and were regarded as pest species. Similarly, the mites like Parasitus consanguineous and Asca biswasi were observed to be predator in nature

House dust mite fauna characterization in the city of Rio de Janeiro and its importance in allergy diagnosis / Caracterização da fauna dos ácaros de poeira na cidade do Rio de Janeiro e sua importância em diagnósticos de alergias

Introduction: The home environment is one of the most favorable spaces for the development of mites because of its low light, humidity, and temperature. Thus, it contributes to the growing cases of allergies among atopic individuals. Objective: To investigate the faunal profile of house dust mites in the city of Rio de Janeiro and the allergenic potential in this region. Methods: Thirty dust samples were collected from homes in the city of Rio de Janeiro, and the species found were classified according to their morphology, family, and genus by classification key. For the collection region, the total protein level was assessed by the Lowry method and electrophoresis under denaturing conditions (SDSPAGE). Results: There was a predominance of Pyroglyphidae mites, accounting for 84.9% of samples; Tyrophagus putrescentiae accounted for 8%, Blomia tropicalis for 6%, Cheyletus malaccensis for 1%, and Acarus siro for 0.1%. The allergen protein content of the samples was the following: group 1 ­ 25 kDa (Der 1, Der p 1, and Blo t 1), group 2 ­ 15 kDa (Der f 2, Der 2, Tyr p 2, and Blo t 2), and group 3 ­ 29-30 kDa (Der f 3 and Blo t 3), which indicates that people in this region are susceptible to sensitization to these mites. Conclusion: Knowledge of the mite fauna in the region under study allows the guidance of health care professionals to perform skin tests for specific mites and conduct treatment according to the pool of mite extracts containing antigens, making immunotherapy more effective.

Introdução: O ambiente domiciliar é um dos espaços favoráveis para o desenvolvimento de ácaros, tendo em vista a baixa luminosidade, umidade e temperatura, o que contribui para os crescentes casos de alergias em indivíduos atópicos. Objetivo: Investigar o perfil faunístico dos ácaros na cidade do Rio de Janeiro e o potencial alergêncio para essa região. Métodos: Foram coletadas 30 amostras de poeira em residências na cidade do Rio de Janeiro, e as espécies encontradas foram classificadas quanto à morfologia, família e o gênero por chave de classificação. Para as regiões das coletas, a carga total de proteínas contendo os alérgenos foi determinada pelo método de Lowry e eletroforese em condições desnaturantes (SDS-PAGE). Resultados: Os resultados mostram a predominância de 84,9% de ácaros da família Pyroglyphidae; para os demais ácaros o percentual corresponde a 8% Tyrophagus putrescentiae, 6% Blomia tropicalis, 1% Cheyletus malaccensis, e 0,1% de Acarus siro. O conteúdo proteico alergêncio constituinte das amostras foram, grupo 1: 25 kDa (Der 1, Der p 1 e Blo t 1); grupo 2: 15 kDa (Der f 2, Der 2, Tyr p 2 e Blo t 2); e para o grupo 3: 29-30 kDa (Der f 3 e Blo t 3), o que indica uma região passível à sensibilização de indivíduos por estes ácaros. Conclusão: O conhecimento da acarofauna nas regiões em estudo permite orientar a comunidade médica quanto à realização de testes cutâneos, além da terapêutica a partir do pool de extratos de ácaros contendo os antígenos, a fim de tornar a imunoterapia mais eficaz.

Investigation of chigger mites on small mammals in Ruili, Yunnan Province, China

@#Chigger mites are arthropods and are the sole vectors of scrub typhus, and rodents as well as other small mammals are the most common hosts of chigger mite larvae. Therefore, it is of great medical significance to study the ecology of chigger mites. In this study, a detailed analysis of chigger mites was conducted based on field survey data. A total of 4,941 chigger mites were collected from 86 hosts at 34 survey sites in Ruili, Yunnan Province, China. Among the 4,941 chiggers, five genera in one subfamily were identified; Schoengastiella ligula was the dominant chigger species with the highest infestation index, prevalence (Pm, 42.86%) and mean intensity (MI, 59.09%) (P<0.001). The association coefficient (V) between S. ligula and Gahrliepia radiopunctata was positively correlated (P<0.05), indicating the tendency of chiggers to select and coexist on the same host at the same time. The dominant species Leptotrombidium kunmingense, Ascoschoengastia indica, S. ligula and G. radiopunctata showed aggregation distribution patterns, indicating that the distribution of chiggers among different hosts was not uniform. Low altitudes and low latitudes appeared to be more favorable for the growth and reproduction of chigger mites (P<0.05). It is suggested to collect as many host samples as possible in future field investigations to better understand the dynamics of chigger mite populations and their primary hosts.

Ácaros en sistemas de ventilación de edificios industriales: bioindicadores de la calidad del aire interior / Mites in ventilation systems of industrial buildings: bioindicators of indoors air quality

La Organización mundial de la Salud, ha señalado que 92% de la población mundial vive en lugares donde los niveles de calidad del aire se han reducido por debajo de los límites fijados, estimando que a nivel mundial aproximadamente 90% de las personas respiran aire contaminado y que la población de las ciudades pasa entre el 80 y el 90% de su tiempo en recintos cerrados, en un ambiente contaminado en mayor o menor grado; puesto que los niveles de contaminación pueden llegar a ser de 10 a 100 veces más elevados en espacios interiores respecto a los exteriores. La deficiencia en la calidad del aire interior puede dar origen a la manifestación de síntomas respiratorios relacionados como rinitis alérgica y asma, entre otras patologías y se estima que, a nivel global, millones de personas sufren de ambas enfermedades, reduciendo la calidad de vida de la población. Los ácaros constituyen los sensibilizantes respiratorios más extendidos en lugares de trabajo y están presentes en casi todos los hábitats, inclusive en el ambiente aéreo, movilizados por el viento o aerosoles, siendo la principal fuente de alérgenos interiores asociados a rinitis y asma. La presente revisión describe las características de los ácaros como fuente de contaminación ambiental y su posible utilidad como futuros bioindicadores de calidad del aire interior en sistemas de ventilación de edificios industriales con el fin de reducir la exposición y sensibilización de los trabajadores a sus alérgenos(AU)

The World Health Organization has pointed out that 92% of the world's population lives in places where air quality levels have fallen below the limits set, estimating that approximately 90% of people worldwide they breathe polluted air and that the population of cities spends between 80 and 90% of their time indoors, in an environment that is polluted to a greater or lesser degree; since pollution levels can be 10 to 100 times higher indoors than outdoors. The deficiency in indoor air quality can give rise to the manifestation of related respiratory symptoms such as allergic rhinitis and asthma, among other pathologies, and it is estimated that, globally, millions of people suffer from both diseases, reducing the quality of life of the population. mites are the most widespread respiratory sensitizers in the workplace and are present in almost all habitats, including in the air environment, moved by the wind or aerosols, being the main source of indoor allergens associated with rhinitis and asthma. This review describes the characteristics of mites as a source of environmental contamination and their possible use as future bioindicators of indoor air quality in ventilation systems of industrial buildings in order to reduce the exposure and sensitization of workers to their allergens(AU)

Lesiones en la piel causadas por ácaros de palomas / Skin lesions caused by bird mites

El prurigo agudo es una patología sumamente frecuente y con múltiples etiologías, entre las cuales se encuentran los ácaros de las aves. La incidencia de esta dermatosis ha aumentado en el último tiempo. Existen diferentes parásitos que colonizan las aves y que, al tener contacto con el ser humano, generan lesiones papulosas de tipo prurigo. El agente causal más involucrado es Dermanyssus gallinae, no siempre hallado en el momento del examen físico. Se presenta el caso de una mujer con lesiones papulosas en el tronco y las extremidades, iniciadas luego del contacto con detritos de palomas.

Acute prurigo is an extremely frequent dermatosis with multiple etiologies, including bird mites. Recently, there has been an increase in the reported cases of human infestation cases caused by bird acarus. Many parasites colonize birds and the infestation to humans produces papular lesions. Dermanyssus gallinae is the most common acarus involved. We report a woman with papular lesions in trunk and extremities after contact with a bird nest.

Efecto de la inmunoterapia con alérgenos específicos en pacientes pediátricos con asma atendidos en una institución de salud de Colombia / Impact of the allergen-specific immunotherapy in pediatric patients with asthma treated at a health institution in Colombia

Resumen Introducción. El asma es una enfermedad crónica y potencialmente grave. El 80 % de los casos es de origen alérgico, por lo cual la inmunoterapia específica con alérgenos es una alternativa terapéutica que modula el curso natural de la enfermedad. Objetivo. Evaluar el impacto de la inmunoterapia en pacientes pediátricos con asma atendidos en una institución de salud de Colombia. Materiales y métodos. Se hizo un estudio observacional descriptivo con componente analítico de corte transversal. Se incluyeron 62 pacientes con diagnóstico de asma alérgica sensibilizados a ácaros del polvo y en tratamiento, mínimo, con seis dosis de inmunoterapia contra ácaros. El efecto del tratamiento se evaluó mediante la escala de puntuación del ACT (Asthma Control Test), la escala de tratamiento de la GINA (Global Initiative for Asthma) y la espirometría. Resultados. La puntuación de la prueba ACT antes del inicio de la inmunoterapia, correspondía a 30 % de pacientes con asma no controlada, 28 % con buen control y 4 % con asma totalmente controlada. Entre los pacientes con asma no controlada, el 46,7 % logró un buen control y el 23,3 % alcanzó un control total. En cuanto a la percepción de los pacientes sobre la mejoría con la inmunoterapia, el 9,75 % percibió una mejoría menor del 50 %, el 45,2 %, una entre el 50 y el 90 %, en tanto que el 41,9 % refirió una igual o mayor del 90 %. No se encontraron cambios significativos en los valores del volumen espiratorio forzado en un segundo (VEF1) en las espirometrías. Conclusiones. Se observaron cambios significativos en los puntajes del ACT y en la percepción de mejoría de la enfermedad en la población tratada con inmunoterapia específica para ácaros, es decir, que esta tendría un efecto beneficioso en el curso natural de la enfermedad

Abstract Introduction: Asthma is a chronic and potentially serious disease and 80% of the cases have an allergic etiology. In this sense, allergen-specific immunotherapy is an alternative that modulates the natural course of the disease. Objective: To evaluate the impact of immunotherapy in pediatric asthma patients treated at a health institution in Colombia. Materials and methods: We conducted an observational descriptive study with an analytical cross-sectional component. Sixty-two patients diagnosed with allergic asthma sensitized to dust mites and treated with at least 6 doses of mite immunotherapy were included. We assessed the impact of immunotherapy using the Asthma Control Test (ACT), the Global Initiative for Asthma (GINA) treatment scale, and spirometry values. Results: The ACT score before the start reported 30% of patients with uncontrolled asthma, 28% with good control, and 4% with totally controlled asthma. Of the patients with uncontrolled asthma, 46.7% achieved good control and 23.3% total control. Regarding patients' perception of improvement with the immunotherapy, 9.75% perceived a response of less than 50%, 45.2% one between 50% -90%, and 41.9% reported response equal to or greater than 90%. No significant changes in FEV1 values were found in spirometry. Conclusions: Significant changes in the ACT scores and the perception of disease improvement were observed in the population evaluated with specific mite immunotherapy, i.e., it had a positive impact on the natural course of the disease.

First record of Blankaartia sinnamaryi (Floch & Fauran, 1956) (Trombidiformes: Trombiculidae) parasitizing the striped owl in Northeastern Brazil / Primeiro registro de Blankaartia sinnamaryi (Floch & Fauran, 1956) (Trombidiformes: Trombiculidae) parasitando uma coruja-listrada no Nordeste do Brasil

Abstract The chigger species Blankaartia sinnamaryi (Floch & Fauran) has been collected mainly from birds with a few records from reptiles and mammals. In Brazil, this species has been found on birds in the Minas Gerais and Rio de Janeiro states. Here, we report the first record of B. sinnamaryi parasitizing the striped owl, Pseudoscops clamator (Vieillot), in the Paraíba state, Brazil (northeastern region).

Resumo A espécie de trombiculídeo, Blankaartia sinnamaryi (Floch & Fauran) tem sido coletada principalmente parasitando aves, com alguns registros em répteis e mamíferos. No Brasil, essa espécie foi encontrada em aves nos estados de Minas Gerais e Rio de Janeiro. No presente estudo, relatamos o primeiro registro de B. sinnamaryi parasitando a coruja-listrada, Pseudoscops clamator (Vieillot), no estado da Paraíba, Brasil (região Nordeste).

Aquatic larval of the genus Arrenurus (Trombidiformes: Parasitengonina: Arrenuridae) associated with Odonata species from Pampa Biome, Brazil / Larvas aquáticas do gênero Arrenurus (Trombidiformes: Parasitengonina: Arrenuridae) associada a espécies de Odonata do bioma Pampa, Brasil

Abstract: Many studies have reported that the interaction between water mite larvae and their Odonata hosts affects mating success, flight, and longevity. Males and females of Odonata species collected in the steppes and coastal plains (Pampa Biome) of Rio Grande do Sul were analyzed. Mites were removed when present and the prevalence and intensity of parasites was calculated. The aim of this study was to search and report new Odonata hosts species that are parasitized by water mite larvae and also to evaluate the prevalence and intensity rates; the differences in mite occurrence and frequency between males and females, and between thorax and abdomen of the dragonflies and damselflies in the southern Pampa biome located in Rio Grande do Sul. A total of 162 larval mites were found associated to two Odonata families: Coenagrionidae (Acanthagrion lancea Selys, 1876, Ischnura capreolus Hagen, 1861 and Ischnura fluviatilis Selys, 1876) and Libelullidae (Micrathyria ocellata Martin, 1897 and Perithemis mooma Kirby, 1889). All mites were identified as Arrenurus (Arrenurus) sp. (Arrenuridae) and showed high numbers when attached to I. capreolus (55.5%), I. fluviatilis (33.3%), followed by low numbers on M. ocellata (6.1%), A. lancea (3.7%), and P. mooma (1.2%). Mites were found on males and females of I. capreolus and I. fluviatilis, females of A. lancea and P. mooma and in M. ocellata only in males. As the parasitized Odonata species are generalist and abundant in all water body types, traits associated with mating and oviposition or larval behavior are believed to explain the frequency of parasitism in these species.

Resumo: Muitos estudos relatam que a interação entre as larvas parasitas e seus hospedeiros Odonata afetam o sucesso do acasalamento, o voo e a longevidade. Foram analisados machos e fêmeas de espécies de Odonata coletados nas estepes e planícies costeiras do bioma Pampa do Rio Grande do Sul. Os ácaros foram removidos quando presentes e a prevalência e intensidade dos parasitas foram calculadas. O objetivo deste estudo foi pesquisar e relatar novas espécies hospedeiras de Odonata que estão parasitadas por larvas de ácaros aquáticos, avaliar as taxas de prevalência e intensidade; avaliar a diferença na ocorrência e frequência de ácaros em fêmeas e machos e entre o tórax e abdômen de libélulas e libelulinhas no bioma Pampa meridional localizado no Rio Grande do Sul. Um total de 162 ácaros foram encontrados associados a duas famílias de Odonata: Coenagrionidae (Acanthagrion lancea Selys, 1876, Ischnura capreolus Hagen, 1861 e Ischnura fluviatilis Selys, 1876) e Libelullidae (Micrathyria ocellata Martin, 1897 e Perithemis mooma, 1889) Kirby. Todos os ácaros foram identificados como Arrenurus (Arrenurus) sp. (Arrenuridae) e apresentaram números elevados quando anexados a I. capreolus (55,5%), I. fluviatilis (33,3%), seguido por números baixos em M. ocellata (6,1%), A. lancea (3,7%) e P. mooma (1,2%). Os ácaros foram encontrados em machos e fêmeas de I. capreolus e I. fluviatilis, fêmeas de A. lancea e P. mooma e em M. ocellata apenas em machos. Como as espécies de Odonata parasitadas são generalistas e abundantes em todos os tipos de corpos d'água, acredita-se que características associadas ao acasalamento e oviposição ou comportamento larval explicam a frequência de parasitismo nessas espécies.

Infestation and distribution of chigger mites on Brown rat (Rattus norvegicus) in Yunnan Province, Southwest China

@#Chigger mites is a group of arthropods and some of them are vectors of scrub typhus. As a common synanthropic rodent species, the Brown rat (Rattus norvegicus) often harbors lots of ectoparasites including chigger mites. According to some “data mining” strategies, the present study took the advantage of the abundant original data from a long-term field ecological investigation between 2001 and 2015 to make a detailed analysis of chigger mites on R. norvegicus in Yunnan Province, Southwest of China. From 18 of 33 investigated counties, only 1414 chigger mites were collected from 1113 Brown rats with relatively low infestations. The 1414 individual chigger mites were identified as comprising 61 species, 11 genera and 2 subfamilies of the family Trombiculidae with a high species diversity (S=61, H’=3.13). Of 61 mite species, there were four main species, Walchia ewingi, Ascoschoengastia indica, W. koi and A. rattinorvegici, which accounted for 44.41% of the total mites. All the chigger mites were of aggregated distribution among different individuals of R. norvegicus. The Brown rats in the outdoor habitats harbored much more individuals and species of chigger mites with a higher mean abundance (MA=1.46) and mean intensity (MI=12.53) than in the indoor habitats (P<0.05). The overall infestation of the rats was significantly higher in the mountainous landscapes than in the flatland landscapes (P<0.001). The species similarity (Css) of the mites on the male and female rats reached 64.44% with sex biased infestations. The male rats harbored more species and individuals of the mites than the female rats. The adult rats harbored more species and individuals of the mites than the juvenile rats. The species abundance distribution of the mites was successfully fitted by Preston’s lognormal model with S