RESUMO
BACKGROUND: Envenomation by the South American Lonomia saturniid caterpillars, named lonomism, constitutes an emerging and somewhat neglected public health issue in Argentina and neighboring countries. Considering that there is an intricate relationship between environment and human health in such cases, this study aimed to analyze the eco-epidemiological profile of 40 accidents and 33 occurrences of Lonomia spp. in Misiones (Argentina) between January 2014 and May 2020. METHODOLOGY/PRINCIPAL FINDINGS: We described the eco-epidemiological variables and characterized the abiotic scenario of such cases. Additionally, we obtained a density map that shows the punctual intensity of Lonomia records throughout Misiones. Most of the accidents occurred in the Department of Guaraní and involved male victims younger than 20 years old. The accidental/occasional occurrence of Lonomia spp. (considering both adult and caterpillar stages together) was significantly higher in the rural area, whereas only adult specimens were found in urban areas. We determined that the presence of this insect in Misiones is positively related to higher temperatures and solar radiation, and larger precipitation and evapotranspiration throughout the year. CONCLUSION/SIGNIFICANCE: This study represents an initial step towards the global understanding of lonomism as a public health problem in Argentina. It provides a map of the risk level for this envenomation in Misiones, which could help authorities address public health policy efforts to implement sustainable strategies for prevention and response to this threat in Northeastern Argentina and neighboring regions.
Assuntos
Venenos de Artrópodes/toxicidade , Mordeduras e Picadas de Insetos/parasitologia , Larva/fisiologia , Mariposas/fisiologia , Adolescente , Adulto , Idoso , Animais , Argentina/epidemiologia , Criança , Pré-Escolar , Ecossistema , Feminino , Humanos , Lactente , Mordeduras e Picadas de Insetos/epidemiologia , Larva/classificação , Masculino , Pessoa de Meia-Idade , Mariposas/classificação , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/parasitologia , Saúde Pública , Adulto JovemRESUMO
Dermatobia hominis, also known as the human botfly, is native to tropical and subtropical Central and South America and seen in travelers from endemic to temperate regions including the United States and Europe. Cutaneous infestation botfly myiasis involves the development of D. hominis larvae in the skin and is common in tropical locations. The distinct appearance of a cutaneous D. hominis infestation facilitates early diagnosis and intervention where cases are common. However, the identification of D. hominis in temperate regions may prove challenging due to its rarity. D. hominis may be misdiagnosed as folliculitis, an epidermal cyst, or an embedded foreign object with secondary impetigo. One should have a heightened suspicion in someone returning from a vacation in an endemic area, such as Belize. Here we describe the presentation, differential diagnosis, and treatment and encourage enhanced preventative measures among tourists when visiting tropical and subtropical regions. Additionally, we propose a novel classification system for assessing the various stages of infestation and suggest that patients reporting travel to Latin America and experiencing pain disproportionate to an insect bite should lead physicians to consider myiasis caused by D. hominis.
Assuntos
Dípteros/patogenicidade , Mordeduras e Picadas de Insetos/complicações , Miíase/diagnóstico , Pele/parasitologia , Doença Relacionada a Viagens , Animais , Antiparasitários/uso terapêutico , Belize/epidemiologia , Diagnóstico Diferencial , Doenças Endêmicas/prevenção & controle , Humanos , Mordeduras e Picadas de Insetos/diagnóstico , Mordeduras e Picadas de Insetos/parasitologia , Repelentes de Insetos/administração & dosagem , Ivermectina , Larva/patogenicidade , América Latina/epidemiologia , Miíase/epidemiologia , Miíase/parasitologia , Miíase/terapia , Roupa de Proteção , Estados UnidosRESUMO
Trypanosoma rangeli is a non-pathogenic protozoan parasite that infects mammals, including humans, in Chagas disease-endemic areas of South and Central America. The parasite is transmitted to a mammalian host when an infected triatomine injects metacyclic trypomastigotes into the host's skin during a bloodmeal. Infected mammals behave as parasite reservoirs for several months and despite intensive research, some major aspects of T. rangeli-vertebrate interactions are still poorly understood. In particular, many questions still remain unanswered, e.g. parasite survival and development inside vertebrates, as no parasite multiplication sites have yet been identified. The present study used an insect bite transmission strategy to investigate whether the vector inoculation spot in the skin behave as a parasite-replication site. Histological data from the skin identified extracellular parasites in the dermis and hypodermis of infected mice in the first 24 hours post-infection, as well as the presence of inflammatory infiltrates in a period of up to 7 days. However, qPCR analyses demonstrated that T. rangeli is eliminated from the skin after 7 days of infection despite being still consistently found on circulating blood and secondary lymphoid tissues for up to 30 days post-infection. Interestingly, significant numbers of parasites were found in the spleen and mesenteric lymph nodes of infected mice during different periods of infection and steady basal numbers of flagellates are maintained in the host's bloodstream, which might behave as a transmission source to insect vectors. The presence of parasites in the spleen was confirmed by fluorescent photomicrography of free and cell-associated T. rangeli forms. Altogether our results suggest that this organ could possibly behave as a T. rangeli maintenance hotspot in vertebrates.
Assuntos
Doença de Chagas/transmissão , Linfonodos/parasitologia , Pele/parasitologia , Baço/parasitologia , Trypanosoma rangeli/isolamento & purificação , Animais , América Central/epidemiologia , Doença de Chagas/epidemiologia , Modelos Animais de Doenças , Interações Hospedeiro-Parasita , Humanos , Mordeduras e Picadas de Insetos/parasitologia , Insetos Vetores/parasitologia , Camundongos , Rhodnius/parasitologia , Sepse/parasitologia , América do Sul/epidemiologiaAssuntos
Erradicação de Doenças , Malária/prevenção & controle , Animais , Anopheles/parasitologia , Argentina/epidemiologia , Controle de Doenças Transmissíveis/economia , Controle de Doenças Transmissíveis/história , Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Importadas/história , Doenças Transmissíveis Importadas/prevenção & controle , Doenças Transmissíveis Importadas/transmissão , Erradicação de Doenças/história , Doenças Endêmicas , Política de Saúde , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Mordeduras e Picadas de Insetos/parasitologia , Insetos Vetores/parasitologia , Malária/epidemiologia , Malária/história , Malária/transmissão , Controle de Mosquitos/economia , Controle de Mosquitos/história , Controle de Mosquitos/métodosRESUMO
ABSTRACT Background: Studies related to infectivity status of insect vectors are seen as necessities in understanding the epidemiology of vector-borne diseases and planning effective control measures. This study assessed the infectivity ofSimulium damnosum s.l. around Owena River as well as evaluated therapeutic coverage of Ivermectin distribution in the area. Method: Human landing sampling method was used to collect adult flies on human attractants from 07:00 to 18:00 for two consecutive days a month for three months (July 2016 - September 2016). Parity assessment was conducted to determine the age of fly populations. Parous flies were further dissected to detect the presence or absence ofOnchocerca larvae. Biting rates and transmission potentials were calculated using standard methods. A quantitative survey was carried out to determine the therapeutic coverage and compliance to ivermectin treatment for the control of Onchocerciasis in the study area using standard household coverage questionnaires. Results: A total of 914 adult female flies were collected during the study period. The daily biting rate (DBR) varied from 146 fly per man day (FMD) in July to 162.5 FMD in August. The monthly biting rate (MBR) was lowest in September (2170 bites per man per month) but highest in August (3358.3 bites per man per month). MBD ranged from 13.23 fly per man hour (FMH) in July to 14.77 FMH in August. The results indicated that the majority of the flies collected at the sampling points were nulliparous [685 (74.95%)] while others were parous [229 (25.05%)]. The biting activity of the flies showed a marked decrease in population in August compared to July which later increased in September. Infection rates varied from 2 (0.7%) in July to 7 (2.2%) in August while the infectivity rate during the study ranged from zero (July and September) to 3 (1.0%) in August. Conclusion: Despite the years of treatment of onchocerciasis in Owena community, there were still some infective flies capable of transmitting O. volvolus. This could be due to the low rate of therapeutic coverage as a result of non-compliance in the community for various reasons earlier stated.
Assuntos
Humanos , Animais , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Oncocercose/tratamento farmacológico , Oncocercose/transmissão , Simuliidae/parasitologia , Ivermectina/uso terapêutico , Mordeduras e Picadas de Insetos/tratamento farmacológico , Antiparasitários/uso terapêutico , Oncocercose/parasitologia , Rios , Mordeduras e Picadas de Insetos/parasitologia , Mordeduras e Picadas de Insetos/epidemiologia , Insetos Vetores/parasitologia , Nigéria/epidemiologiaRESUMO
BACKGROUND: Studies related to infectivity status of insect vectors are seen as necessities in understanding the epidemiology of vector-borne diseases and planning effective control measures. This study assessed the infectivity ofSimulium damnosum s.l. around Owena River as well as evaluated therapeutic coverage of Ivermectin distribution in the area. METHOD: Human landing sampling method was used to collect adult flies on human attractants from 07:00 to 18:00 for two consecutive days a month for three months (July 2016 - September 2016). Parity assessment was conducted to determine the age of fly populations. Parous flies were further dissected to detect the presence or absence ofOnchocerca larvae. Biting rates and transmission potentials were calculated using standard methods. A quantitative survey was carried out to determine the therapeutic coverage and compliance to ivermectin treatment for the control of Onchocerciasis in the study area using standard household coverage questionnaires. RESULTS: A total of 914 adult female flies were collected during the study period. The daily biting rate (DBR) varied from 146 fly per man day (FMD) in July to 162.5 FMD in August. The monthly biting rate (MBR) was lowest in September (2170 bites per man per month) but highest in August (3358.3 bites per man per month). MBD ranged from 13.23 fly per man hour (FMH) in July to 14.77 FMH in August. The results indicated that the majority of the flies collected at the sampling points were nulliparous [685 (74.95%)] while others were parous [229 (25.05%)]. The biting activity of the flies showed a marked decrease in population in August compared to July which later increased in September. Infection rates varied from 2 (0.7%) in July to 7 (2.2%) in August while the infectivity rate during the study ranged from zero (July and September) to 3 (1.0%) in August. CONCLUSION: Despite the years of treatment of onchocerciasis in Owena community, there were still some infective flies capable of transmitting O. volvolus. This could be due to the low rate of therapeutic coverage as a result of non-compliance in the community for various reasons earlier stated.
Assuntos
Antiparasitários/uso terapêutico , Mordeduras e Picadas de Insetos/tratamento farmacológico , Ivermectina/uso terapêutico , Oncocercose/tratamento farmacológico , Oncocercose/transmissão , Simuliidae/parasitologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Feminino , Humanos , Mordeduras e Picadas de Insetos/epidemiologia , Mordeduras e Picadas de Insetos/parasitologia , Insetos Vetores/parasitologia , Masculino , Pessoa de Meia-Idade , Nigéria/epidemiologia , Oncocercose/parasitologia , Rios , Adulto JovemRESUMO
Count data commonly arise in natural sciences but adequately modeling these data is challenging due to zero-inflation and over-dispersion. While multiple parametric modeling approaches have been proposed, unfortunately there is no consensus regarding how to choose the best model. In this article, we propose a ordinal regression model (MN) as a default model for count data given that this model is shown to fit well data that arise from several types of discrete distributions. We extend this model to allow for automatic model selection (MN-MS) and show that the MN-MS model generates superior inference when compared to using the full model or more traditional model selection approaches. The MN-MS model is used to determine how human biting rate of mosquitoes, known to be able to transmit malaria, are influenced by environmental factors in the Peruvian Amazon. The MN-MS model had one of the best fit and out-of-sample predictive skill amongst all models. While A. darlingi is strongly associated with highly anthropized landscapes, all the other mosquito species had higher mean biting rates in landscapes with a lower fraction of exposed soil and urban area, revealing a striking shift in species composition. We believe that the MN and MN-MS models are valuable additions to the modelling toolkit employed by environmental modelers and quantitative ecologists.
Assuntos
Anopheles/parasitologia , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Mordeduras e Picadas de Insetos/epidemiologia , Malária/epidemiologia , Modelos Estatísticos , Distribuição Animal , Animais , Humanos , Mordeduras e Picadas de Insetos/parasitologia , Malária/parasitologia , Malária/transmissão , Peru/epidemiologia , Distribuição de Poisson , Análise de RegressãoRESUMO
Abstract: Human, dog, and cat fleas, as well as bedbugs, feed by biting their victims, causing acute prurigo, which is aggravated in sensitized victims (papular urticaria). The lesions appear in the classic "breakfast, lunch, and dinner" pattern. There are two main explanations: the parasites "map" the skin area in search of the best places to bite, and their removal when victim scratches, and then reattach to the skin. Treatments aim to control pruritus, as well as hypersensitivity reactions when necessary. Prevention is based on environmental control measures. The "breakfast, lunch, and dinner" sign is a definitive marker for diagnosis and the parasite´s identification and control.
Assuntos
Humanos , Animais , Percevejos-de-Cama , Infestações por Pulgas/veterinária , Mordeduras e Picadas de Insetos/parasitologia , Prurido/etiologia , Fotografação , Gatos/parasitologia , Cães/parasitologia , Sifonápteros , Mordeduras e Picadas de Insetos/diagnóstico , Mordeduras e Picadas de Insetos/patologiaRESUMO
Sclerodermus sp. is an aculeate insect (Hymenoptera: Bethylidae), measuring 2-4 mm in length. It is a parasitoid and needs termites as hosts to complete its life cycle. It is found in a wide variety of woods and may accidentally sting humans who come near affected wooden objects. A 50-year-old woman presented two episodes of intense pruritic lesions. Clinical diagnosis of insect bite was doubtful since there were no pets at home, lesions had not started during summer and the patient denied rural activities. During a night episode of itching, the patient examined her bed and found 8 insects likely to be responsible for the bites. Scanning electron microscopy revealed typical features of a female of the genus (wingless and with multiple stingers at the lower end of the abdomen).