Introduction of the ectoparasite Rhipicephalus pulchellus (Ixodida: Ixodidae) into Connecticut with a human traveler from Tanzania, and a review of its importation records into the United States.

Globalization, increased frequency of travel, and a rise in legal and illegal animal trades can introduce exotic ticks into the United States. We herein report the importation of a male Rhipicephalus pulchellus (Gerstäcker) on a human traveler returning to Connecticut from Tanzania, Africa, and review historical importation records of this species into the United States. This common tick is broadly distributed throughout East Africa, from Eritrea to Tanzania, has a wide host range on domestic animals and wildlife, and has been most frequently introduced into the United States on tick-infested wild animal hosts and animal trophies, but documentation of importation on humans has been rare. Archival records at the United States Department of Agriculture's National Veterinary Services Laboratories show R. pulchellus has been introduced into the United States at least 40 times over the last 62 yr. Rhipicephalus pulchellus has been linked to Rickettsia conorii, the agent of boutonneuse fever in humans, Crimean-Congo hemorrhagic fever orthonairovirus, and Nairobi sheep disease orthonairovirus. Given the potential for this exotic tick to introduce animal or human pathogens, proper surveillance, interception, identification, and reporting of these ticks are vital in protecting human and animal health.

Sleeping with the enemy: case reports of Ornithonyssus bursa (Berlese, 1888) (Mesostigmata: Macronyssidae) causing human dermatitis in Brazil.

Ornithonyssus bursa, known as the "tropical fowl mite," is a hematophagous mite of domestic and wild birds, which occasionally bites humans. Accidental bites on humans occur mainly when abandoned bird nests are close to homes or when people are handling parasitized birds. In the present study, we describe five case reports of bites on humans and new records of localities for this species. Based on the material examined, we provide morphological and molecular characterizations for this species herein.

Sleeping with the enemy: case reports of Ornithonyssus bursa (Berlese, 1888) (Mesostigmata: Macronyssidae) causing human dermatitis in Brazil

Ornithonyssus bursa, known as the “tropical fowl mite,” is a hematophagous mite of domestic and wild birds, which occasionally bites humans. Accidental bites on humans occur mainly when abandoned bird nests are close to homes or when people are handling parasitized birds. In the present study, we describe five case reports of bites on humans and new records of localities for this species. Based on the material examined, we provide morphological and molecular characterizations for this species herein.

Detection of Dermacentor andersoni (Acari: Ixodidae) in Brazil on a Human Traveler Returning from the United States.

Only one previous record of an exotic tick on a Brazilian traveler has been reported. Here, we report the detection of Dermacentor andersoni (Stiles) in Brazil while attached to a human traveler returning from the United States. This report is the fifth record of D. andersoni as an exotic tick, and the second record of an exotic tick on a South American traveler.

An instance of parasitism on a human by a nymph of the kangaroo soft tick, Ornithodoros gurneyi Warburton, 1926 (Acari: Argasidae) in South Australia.

The kangaroo soft tick, Ornithodoros gurneyi Warburton, 1926, is a poorly studied argasid of the more arid regions of Australia. Anecdotal accounts have stated that this tick species will bite humans, and yet bites have not been described. Herein we report on an instance of parasitism by a nymph of O. gurneyi on a human, and we provide a summary of confirmed instances of parasitism on humans by this tick based on museum specimens.

Human Parasitism by Amblyomma parkeri Ticks Infected with Candidatus Rickettsia paranaensis, Brazil.

Spotted fever is the main rickettsial disease in Brazil. We report 12 cases of human parasitism by Amblyomma parkeri in the Atlantic rainforest, an area of Brazil to which spotted fever is endemic. Nine of the ticks were infected with Candidatus Rickettsia paranaensis.

Dermatitis in humans caused by Ornithonyssus bursa (Berlese 1888) (Mesostigmata: Macronyssidae) and new records from Brazil / Dermatite em humanos causada por Ornithonyssus bursa (Berlese 1888) (Mesostigmata: Macronyssidae) e novos registros para o Brasil

Abstract Ornithonyssus bursa, known as the "tropical fowl mite", is a hematophagous mite of domestic and wild birds, occasionally biting humans. Infestation on humans occurs mainly when the abandoned nests are close to homes, or by manipulation of infested birds by humans. In Brazil, this species occurs in the south and southeast of the country. In the present study we are reporting bites on humans, new localities records, host associations, and molecular information of O. bursa.

Resumo Ornithonyssus bursa, conhecido como "ácaro tropical de galinha", é um ácaro hematófago de aves domésticas e silvestres, ocasionalmente picando humanos. A infestação em humanos ocorre principalmente quando os ninhos abandonados de aves estão próximos de casas, ou pela manipulação de humanos de aves infestadas. No Brasil, esta espécie ocorre na região sul e sudeste do país. No presente estudo, estamos relatando picadas em humanos, registros de novas localidades de ocorrência, novo hospedeiro e informações moleculares de O. bursa.

Occupational risk for personnel working in veterinary clinics through exposure to vectors of rickettsial pathogens.

Workers at veterinary clinics are exposed to zoonotic pathogens, which, though infrequently, can lead to serious consequences. The aim of the present study was to estimate the seroprevalence for rickettsial pathogens in veterinary clinic personnel in Ciudad Juárez, Chihuahua, Mexico. Voluntary participants included 106 veterinarians, 19 pet groomers, 36 veterinary assistants and 6 administrative workers who supplied blood samples taken by venipuncture. Detection of Rickettsia rickettsii, Ehrlichia spp. and Anaplasma phagocytophilum was conducted by indirect immunofluorescence assay (IFA) and polymerase chain reaction (PCR) techniques. To determine risk factors for the seroprevalence, the study considered social, demographic and occupational variables as well as the clinical signs and symptoms of the participants. Logistic regression procedures were performed, and the odds ratio (OR) was calculated with confidence intervals corresponding to a probability of 95%. The results indicate that 54% of the participants had a positive seroreaction to at least one of the pathogens evaluated and 2% were positive to all. The coexposure was as follows: 3% to R. rickettsii and A. phagocytophilum, 9% to Ehrlichia spp. and A. phagocytophilum, and 2% to Ehrlichia spp. and R. rickettsii. It was established that grooming posed the highest risk for R. rickettsii exposure. The implementation of appropriate management practices for zoonotic diseases is recommended to avoid health problems that may be life threatening to personnel in veterinary clinics.

Dermatitis in humans caused by Ornithonyssus bursa

Ornithonyssus bursa, known as the "tropical fowl mite", is a hematophagous mite of domestic and wild birds, occasionally biting humans. Infestation on humans occurs mainly when the abandoned nests are close to homes, or by manipulation of infested birds by humans. In Brazil, this species occurs in the south and southeast of the country. In the present study we are reporting bites on humans, new localities records, host associations, and molecular information of O. bursa.

A morphological and phylogenetic analysis of Ornithodoros marinkellei (Acari: Argasidae), with additional notes on habitat and host usage.

Ornithodoros marinkellei was described from larvae collected on Pteronotus spp. bats in Colombia and Panama. More recently, this tick was reported in the Brazilian Amazon. Because some morphometric differences were observed between O. marinkellei larvae from Colombia and Brazil, it was proposed that further investigations were needed to assess whether the differences could be attributed to intra- or inter-specific polymorphism. Herein, we collected O. marinkellei specimens in the type locality of Colombia, in Brazil, and in a new locality in Nicaragua, expanding the distribution of the species to Nicaragua. Morphometric analysis of larvae and adults, corroborated by a principal component analysis (PCA), indicated that the Brazilian specimens were larger than specimens from Colombia and Nicaragua. Phylogenetic analysis inferred from the mitochondrial 16S rRNA gene showed ticks from Colombia and Nicaragua more genetically related than any of them with ticks from Brazil, although ticks from the three countries grouped in a clade sister to a major clade containing sequences of various Neotropical Ornithodoros species. We concluded that ticks identified as O. marinkellei from Colombia, Nicaragua, and Brazil represent the same taxon, and that the genetic and morphological differences between them are likely to have a geographical bias. We redescribed the nymph of O. marinkellei, which has a vestigial hypostome, probably incompatible with blood feeding. We also report human infestation by O. marinkellei adults. As all reports of O. marinkellei adults have been from hot caves (temperature > 35 °C), this abiotic condition could be a limiting factor for the occurrence of this tick species.

Human parasitism by Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) in Mato Grosso do Sul, West-Central Brazil / Parasitismo humano por Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) no Mato Grosso do Sul, Centro-Oeste do Brasil

Human parasitism by the brown dog tick Rhipicephalus sanguineus sensu lato (s. l.), an important parasite in medical and veterinary sciences, is only rarely reported in the American continent. The present investigation reports a R. sanguineus s. l. male tick parasitizing a human in the city of Campo Grande, State of Mato Grosso do Sul, west-central Brazil. This observation is of public health relevance, since R. sanguineus s. l. ticks are known as vectors of spotted fever group rickettsiae to dogs and humans.(AU)

O parasitismo humano pelo carrapato marrom do cão, Rhipicephalus sanguineus sensu lato (s. l.), um importante parasita para a saúde pública e veterinária, é raramente relatado no continente americano. Este trabalho relata o registro de um macho de R. sanguineus s. l. parasitando um humano na cidade de Campo Grande, estado do Mato Grosso do Sul, no Centro-Oeste do Brasil. Essa observação é relevante para a saúde pública, uma vez que os carrapatos desse complexo são conhecidos como vetores de riquétsias do grupo da febre maculosa para cães e humanos.(AU)

Successful Feeding of Amblyomma coelebs (Acari: Ixodidae) Nymphs on Humans in Brazil: Skin Reactions to Parasitism.

Identifying the tick species that successfully feed on humans would increase knowledge of the epidemiology of several tick-borne diseases. These species salivate into the host, increasing the risk of pathogen transmission. However, there is a lack of data in the literature regarding the ticks that prefer to feed on humans. Herein, we describe the successful feeding of Amblyomma coelebs Neumann nymphs on two of the authors after accidental tick bites occurred during field surveys in two preserved areas of Mato Grosso do Sul, Brazil. One of the host-parasite interactions was closely monitored, and the tick development, gross host skin alterations, and related sensations are presented.

Occurrence of Ornithodoros brasiliensis Aragão (Acari: Argasidae) in São Francisco de Paula, RS, Southern Brazil

There have been no reports of the endemic Ornithodoros brasiliensis (Aragão) in Rio Grande do Sul, southern Brazil, since the 1950s. In January 2007, 21 O. brasiliensis ticks were collected in a rural area named "Cruzinha" in the municipality of São Francisco de Paula, RS, and another population was sampled later that year (October) in Vargem do Cedro, another rural area of São Francisco de Paula, following reports of human parasitism by ticks. The reappearance of this tick is a reason for concern in terms of public health.

Intestinal pathology in human metagonimiasis with ultrastructural observations of parasites

A human case of intestinal metagonimiasis that was incidentally found during the histological examination of a resected segment of jejunum was described. The small adults trematode of Metagonimus yokogawai were found free in jejunal lumen as well as impacted in intervillous spaces. Histologically intestinal lesions were massive lymphoplasmacytic and eosinophilic infiltration in stroma, erosion of neanby enterocytes, goblet cell depletion and occasional villous edema. Scanning electron microscopy revealed the worm of spatulate appearance with rake-shaped tegumental spines. By transmission electron microscopy, the syncytial integument with dense discoidal bodies, basement membrane muscle cells and subtegumental cells were observed. Characteristic junctional complex was demonstrated between subtegumental and parenchymal cells as well as between parenchymal cells.