Behavioral, Physiological, Demographic and Ecological Impacts of Hematophagous and Endoparasitic Insects on an Arctic Ungulate.

Animals that deliver a toxic secretion through a wound or to the body surface without a wound are considered venomous and toxungenous, respectively. Hematophagous insects, such as mosquitoes (Aedes spp.), meet the criteria for venomous, and some endoparasitic insects, such as warble flies (Hypoderma tarandi), satisfy the definition for toxungenous. The impacts of these insects on their hosts are wide ranging. In the Arctic, their primary host is the most abundant ungulate, the caribou (Rangifer tarandus). The most conspicuous impacts of these insects on caribou are behavioral. Caribou increase their movements during peak insect harassment, evading and running away from these parasites. These behavioral responses scale up to physiological effects as caribou move to less productive habitats to reduce harassment which increases energetic costs due to locomotion, reduces nutrient intake due to less time spent foraging, and can lead to poorer physiological condition. Reduced physiological condition can lead to lower reproductive output and even higher mortality rates, with the potential to ultimately affect caribou demographics. Caribou affect all trophic levels in the Arctic and the processes that connect them, thus altering caribou demographics could impact the ecology of the region. Broadening the definitions of venomous and toxungenous animals to include hematophagous and endoparasitic insects should not only generate productive collaborations among toxinologists and parasitologists, but will also lead to a deeper understanding of the ecology of toxic secretions and their widespread influence.

A world review of reported myiases caused by flower flies (Diptera: Syrphidae), including the first case of human myiasis from Palpada scutellaris (Fabricius, 1805).

Rat-tailed larvae of the syrphid species Palpada scutellaris (Fabricius, 1805) are documented causing an enteric human myiasis in Costa Rica. This is the first time that the genus Palpada is recorded as a human myiasis agent. We report a 68-year-old woman with intestinal pain and bloody diarrhea with several live Palpada larvae present in the stool. Using molecular techniques (DNA barcodes) and both electronic and optical microscopy to study the external morphology, the preimaginal stages of the fly were unambiguously identified. An identification key to all syrphid genera actually known as agents of human and animal myiases is provided for larvae, puparia, and adults. Moreover, a critical world review of more than 100 references of Syrphidae as myiasis agents is also given, with emphasis on the species with rat-tailed larvae.

Human ophthalmomyiasis caused by Oestrus ovis-first report from Croatia and review on cases from Mediterranean countries.

Oestrus ovis is the most common cause of human ophthalmomyiasis. So far, majority of ophthalmomyiasis cases have been reported from Mediterranean countries, but not from Croatia. In current study, we present first two cases of human ophthalmomyiasis in Croatia, caused by O. ovis larvae. Reviewing a PubMed database, additional 259 cases of human ophthalmomyiasis in countries of Mediterranean basin have been reported. A total of 260 (99.62%) cases had external, while 1 (0.38%) had internal form of ocular myiasis. In all cases, O. ovis larvae were identified as the causative agent. O. ovis infestation is usually reported in shepherds and farmers although there is a high prevalence of infection in urban areas as well. Various climatic factors influence O. ovis larvipositional activity. Air temperature is the most important factor affecting O. ovis larviposition, while humidity, wind speed, and time of the day play only a moderate role. Most common symptoms of ophthalmomyiasis are irritation and redness, and in more than half of cases infestation is multiple. Ophthalmomyiasis interna is eye-compromising condition. Since there is reduced awareness among patients and medical professionals, the real number of ophthalmomyiasis cases is probably significantly higher than published. Global warming predisposes future increase of O. ovis prevalence in humans, which emphasizes the need for mandatory reporting and surveillance of disease.

Histological and Immunohistochemical Study of Wounds in Sheep Skin in Maggot Therapy by Using Protophormia terraenovae (Diptera: Calliphoridae) Larvae.

A study was performed to evaluate the implication of Protophormia terraenovae larvae as a surgical therapy for wounded skin. Three groups of sheep (n = 25) were considered based on larval doses. Groups 1 and 2 were artificially infested with low and high concentrations of L1 stage P. terraenovae, respectively, and group 0 served as a control. Skin biopsies were taken at 4 and 14 d postinfestation (D.P.If). A histopathological study was carried out to evaluate the lesions with a score, numbers of eosinophils and mast cells, and an immunohistochemical analysis of CD3, CD79α, and CD68 as T lymphocytes, B lymphosytes, and macrophages, respectively. The results indicated that higher larval doses led to faster regeneration by 14 D.P.If. Furthermore, the higher larval doses showed a high number of the CD68 marker and eosinophils and a low number of CD3 and CD79α markers and mast cells. In addition, the number of mast cells, T lymphocytes, and macrophage markers increased when the lesion progressed; however, a low number of immunolabeled CD79α cells and eosinophils were observed. The results indicate a possible positive effect of larvae in the healing of certain wounds.

Systemic manifestations of Cuterebra infection in dogs and cats: 42 cases (2000-2014).

OBJECTIVE To document clinical signs in cats and dogs with Cuterebra infection, determine the outcome of infected animals, and determine whether Yorkshire Terriers were more commonly affected than other breeds of dogs. DESIGN Retrospective case series. ANIMALS 22 cats and 20 dogs with Cuterebra infection. PROCEDURES Medical records of dogs and cats with Cuterebra infection were reviewed for signalment, history, clinical and laboratory findings, treatment, duration of hospitalization, and outcome. RESULTS Most (16/20 [80%]) of the dogs weighed ≤ 4.5 kg (10 lb), and Yorkshire Terriers were overrepresented (8/20 [40%]), compared with dogs of other breeds. Ten (50%) dogs and 3 (14%) cats had systemic inflammatory response syndrome at the time of initial evaluation, and 8 (40%) dogs but none of the cats had disseminated intravascular coagulation. The overall mortality rate was 17% (7/42), but was higher for dogs (6/20 [30%]) than cats (1/22 [4.5%]). All 6 dogs that died weighed ≤ 4.5 kg and had systemic inflammatory response syndrome, disseminated intravascular coagulation, or both. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that Cuterebra infection can cause severe systemic illness in small-breed dogs. Yorkshire Terriers were more commonly affected than were dogs of other breeds and, subjectively at least, appeared to be more likely to develop severe systemic illness.

Pleural Myiasis Associated With Pleural Angiosarcoma.

Myiasis refers to a parasitic infestation of vertebrate mammals by dipterous larvae (maggots) of higher flies. Infections in humans typically occur in tropical and subtropical regions, regions with limited medical access, and areas with poor hygiene and living conditions. Infestations in humans have been described in subcutaneous, nasal, ocular, oropharyngeal, and orotracheal cases; however, reports of pulmonary myiasis in humans in the United States and other developed countries are extremely rare. We describe a patient with recently diagnosed primary pleural angiosarcoma who presented to our clinic for the management of a thoracostomy tube and was diagnosed with pleural myiasis.

Rara miasis maxilar por Cochliomyia hominivorax. Reporte de caso, actualidad y entomología / A rare maxillary myiasis due to Cochliomyia hominivorax. A case report, update and entomology

La miasis maxilar es un raro padecimiento tropical y endémico de varias zonas del mundo, propio de algunos mamíferos, y el hombre no es la excepción. A continuación presentamos el primer reporte de miasis de este tipo en Ecuador, caracterizamos una masiva invasión larvaria y analizamos casos similares reportados en la literatura médica (AU)

Maxillary myiasis is a rare tropical disease, it is endemic in several areas around the world, and common of some mammals, although humans are not excluded. The first case of maxillary myiasis in Ecuador is presented, as well as a description of the massive larval invasion. Similar cases reported in the medical literature are also reviewed (AU)

Myiasis in Travelers.

BACKGROUND: Cutaneous myiasis is a well-established diagnosis in returning travelers from tropical countries. The most common form of myiasis seen in this population is localized furuncular myiasis caused by Dermatobia hominis and Cordylobia anthropophaga. There are limited data on the disease course and outcome in travelers to tropical countries. METHODS: A retrospective observational study of patients who presented with myiasis was conducted between 1999 and July 2014 in the post-travel clinics in Israel. Data regarding exposure history, travel duration, clinical presentation, treatment, and parasitological identification were collected and analyzed. RESULTS: Among 6,867 ill returning Israeli travelers, 1,419 (21%) had a dermatologic complaint, 90 (6.3%) of them were diagnosed with myiasis. Myiasis was acquired in Latin America by 72 (80%) patients, mainly (54%) in the Madidi National Park, Amazonas Basin, Bolivia; 18 cases (20%) were acquired in Africa. In 76% of cases, manual extraction was sufficient to remove the larva; 24% required surgical intervention. Despite the fact that most patients did not receive antibiotic treatment, only one developed secondary infection, upon partial removal of the larva. CONCLUSIONS: This is the largest myiasis case series in ill returning travelers. Myiasis is not a rare dermatologic complaint with most Israeli cases imported from Latin America and specifically the Madidi National Park in Bolivia. Treatment is based on full extraction of the larva after which no antibiotic treatment is needed. Myiasis is a preventable disease and travelers should be informed of the different preventive measures according to their travel destination.

Furuncular myiasis in 2 American travelers returning from Senegal.

Furuncular myiasis caused by Cordylobia anthropophaga larvae is commonly seen in Africa but rarely is diagnosed in travelers returning from the sub-Saharan region. We report 2 cases of furuncular myiasis due to Cordylobia species in adolescent American travelers returning from Senegal.

Myiasis (fly disease) and insectal disease generally are causing mental illness.

Mental illness by which psychosis is meant here is known to be caused mainly by imbalances of certain neurotransmitters in the brain. But, what is causing these imbalances? There has been a recent flurry of interest focusing on the possibility of parasitical disease. The appropriateness of this is based on the fact that organisms of the animal kingdom produce the same neurotransmitters. In fact stinging insects release them in their venoms. The proposal here is that insect larval parasites acting on the human brain and body may release such neurotransmitters and cause imbalances and altered mental states and is supported by the occurrence of previously unexplained physical symptoms such as; diarrhoea, constipation, spasms, anaemia, bloating, insomnia, headache, migraine, weight loss, low blood pressure, low grade fever, amnesia and signs of allergy which may accompany mental illness. Some of these symptoms have been previously attributed to the medications prescribed to alleviate the psychotic symptoms but, many are also parasitical signs. It is proposed that the minute larvae may make sudden movements and may be highly motile and may move from pressure, hence evading the phlebotomist's needle. There is also the testimony of those with delusional parasitosis and related addictions, I propose the regularity with which humans are bitten, stung and have their foods infected with insects at all stages as a demonstration of how insectal disease may have the potential for common infection and disease; mental and physical.

Cutaneous superficial myiasis: report of a rare nosocomial parasitic disease caused by Sarcophaga spp. (diptera, sarcophagidae).

Flies of the genus Sarcophaga are known to cause myiasis in necrotic wounds and in anatomical cavities where fluids have collected. We present here the first case of external cutaneous myiasis by Sarcophaga larvae in the absence of skin ulcerations or necrosis. The host in this case was a geriatric patient with limited motor and neurological capacity who lives in a nursing home. Of particular importance is that Sarcophaga is capable of causing myiasis even in the absence of cutaneous infections or significant stasis of fluids or secretions and that the larvae can cause damage in otherwise healthy tissue.

Human ophthalmomyiasis interna caused by Hypoderma tarandi, Northern Canada.

Human myiasis caused by bot flies of nonhuman animals is rare but may be increasing. The treatment of choice is laser photocoagulation or vitrectomy with larva removal and intraocular steroids. Ophthalmomyiasis caused by Hypoderma spp. should be recognized as a potentially reversible cause of vision loss.

Miíases humanas / Human myiasis

Condição mórbida causada por ectoparasitos - larvas de vetores dípteros. Podem ser classificados, de acordo com a natureza do agente etiológico, em específicas, semi-específicas e acidentes ou, ainda, em miíase cutânea ou cavitária. O diagnóstico é estabelecido em bases clínicas. O tratamento consiste na remoção mecânica de cada uma das larvas ou no oclusão do óstio de entrada da lesão, a fim de sufocar o parasito. O artigo objetiva a revisão de aspectos relevantes, correlacionados com a parasitose

Scanning electron microscopy of Dermatobia hominis reveals cutaneous anchoring features.

We report the case of a 45-year-old Caucasian woman suffering from cutaneous myiasis. With the use of scanning electron microscopy, we placed special focus on the mechanisms by which Dermatobia hominis can fasten securely within the human skin.

Some physiological responses associated with reduced wool growth during blowfly strike in Merino sheep.

OBJECTIVE: To examine the effect on wool growth of physiological changes associated with experimental flystrike in superfine Merino wethers. DESIGN: An animal house study comparing experimentally fly struck sheep with non-infected control groups that were pair fed or fed ad libitum. PROCEDURE: Sheep in the blow fly larval challenge group were each artificially infected with 500 first instar larvae per day for 8 days. Infections were terminated with insecticide on day 10. For all sheep, live weight change, feed intake and body temperature were monitored and blood collected for analysis of haematology, cortisol, serum haptoglobin, serum amyloid A and the pro-inflammatory cytokines, TNFa, IL-1 b, IL-6 and IL-8. Wool growth and staple strength were examined 4 months after infection. RESULTS: Experimental fly strike included moderate fever, depressed feed intake, and elevated cortisol, IL-6, serum amyloid A and haptoglobin. Staple strength was significantly decreased in struck sheep and did not differ between wool from sites adjacent to and remote from strike lesions. CONCLUSIONS: The results suggest that depression in feed intake alone is not sufficient to account for the decline in staple strength seen during fly strike. Cortisol, IL-6 and metabolic consequences of the acute phase response are likely to be major contributors to the systemic effects of blowfly strike on wool.