Molecular Diagnosis and Prevalence of Trypanosoma vivax (Trypanosomatida: Trypanosomatidae) in Buffaloes and Ectoparasites in the Brazilian Amazon Region.

Trypanosoma vivax Ziemann is a parasite that affects both wild and domestic ungulates and is transmitted mechanically via tabanids and other blood-sucking insects in the Americas. A total of 621 blood samples from water buffaloes (Bubalus bubalis (Linnaeus) (Artiodactyla: Bovidae), and 184 ectoparasite samples (Amblyomma cajennense (Fabricius) sensu stricto and Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae), and Haematopinus tuberculatus (Burmeister) (Phthiraptera: Haematopinidae)) were obtained from 60 farms in the State of Pará, Brazilian Amazon. Twelve buffalo blood samples (1.89%) and 11 ectoparasites (6%) were positive for T. vivax based on the cathepsin L-like gene. All sequences were 99% similar to T. vivax from northeastern Brazil (EU753788) in amplified PCR assays on each of the hosts tested.

Parasites of small Indian mongoose, Herpestes auropunctatus, on St. Kitts, West Indies.

Herpestes auropunctatus, the small Indian mongoose, is an invasive omnivore introduced to the Caribbean, including the island of St. Kitts over 150 years ago. It has played a role in changing native fauna and can carry zoonotic pathogens of public health importance. The aim of the current study was to estimate the prevalence of parasites harbored by mongooses. In total, 87 mongooses trapped from April to July 2015 were examined for parasites using (1) hair plucks (N = 79), ear swabs (N = 79), and general coat and skin examination (N = 87) for mites, ticks, lice, and fleas; (2) dissection of the trachea, bronchi, and lungs for lungworms and flukes (N = 76); (3) a double centrifugation fecal flotation method for parasites of the gastrointestinal tract (N = 75); and (4) PCR of heart homogenates for Toxoplasma gondii (N = 60). The only ectoparasite seen was Ctenocephalides felis (79.3%; 69/87), with most mongooses having > 10 fleas (based on a subjective assessment) but insufficient numbers to result in signs of pruritus or anemia. On fecal flotation, coccidial oocysts were found with a prevalence of 69.3% (52/75). Neither T. gondii, lungworm, nor fluke infections were detected with the methods used. The high number of C. felis-infested mongooses and the infestation level of the individual mongooses suggest that they could serve as a reservoir for these potential vectors of pathogens. No evidence was found to support that mongooses are a component of T. gondii cycles on St. Kitts, although this finding needs to be confirmed with a larger sample size from other geographic locations.

Mechanical transfer of Theileria orientalis: possible roles of biting arthropods, colostrum and husbandry practices in disease transmission.

BACKGROUND: The intracellular protozoal parasite Theileria orientalis has rapidly spread across South-eastern Australia, substantially impacting local cattle industries since 2006. Haemaphysalis longicornis appears to be a biological vector in the endemic regions. Mechanical transfer of blood by biting arthropods, in colostrum or iatrogenic transmission though husbandry procedures is another possible mode of transmission. This study assesses the risk of these mechanical modes of transmission. METHODS: Blood was collected from a T. orientalis Ikeda positive Angus steer, and was inoculated into the jugular vein of 9 calves in 3 treatment groups, each with 3 animals. Calves in Group 1 received 10 ml of cryopreserved blood, while those in Groups 2 and 3 received 1 ml (fresh blood) and 0.1 ml (cryopreserved), respectively. An additional three animals remained as negative controls and the donor calf was also followed as a positive control. Blood was collected over 3 months, and analysed via qPCR for the presence of the parasite. Samples of the sucking louse Linognathus vituli were collected opportunistically from calves 5 months after inoculation and tested for T. orientalis. For the colostral transmission study, 30 samples of blood and colostrum were collected from cows at calving in an endemic herd. These samples along with blood from their calves were tested by qPCR for T. orientalis and for antibodies to the major piroplasm surface protein (MPSP). RESULTS: Eight of the nine inoculated calves became positive for T. orientalis. The prepatent period of these infections was inversely correlated with inoculation dose. All negative control calves remained negative and the positive control calf remained positive. Samples of L. vituli tested positive for T. orientalis Ikeda, while some samples of colostrum were also shown to be qPCR and anti-MPSP positive. All calves in the colostral study tested qPCR negative although one was antibody-positive. CONCLUSIONS: T. orientalis is capable of being mechanically transferred by intravenous inoculation with small volumes of blood and is detectable up to 5 months post-infection. Animals infected by this means may play a significant role in the transmission of the disease by acting as asymptomatic carriers. Other modes of blood transfer, including biting arthropods and colostral transfer are also possible modes of disease transmission.

Phocid seals, seal lice and heartworms: a terrestrial host-parasite system conveyed to the marine environment.

Adaptation of pinnipeds to the marine habitat imposed parallel evolutions in their parasites. Ancestral pinnipeds must have harboured sucking lice, which were ancestors of the seal louse Echinophthirius horridus. The seal louse is one of the few insects that successfully adjusted to the marine environment. Adaptations such as keeping an air reservoir and the ability to hold on to and move on the host were necessary, as well as an adjustment of their life cycle to fit the diving habits of their host. E. horridus are confined to the Northern Hemisphere and have been reported from 9 species of northern phocids belonging to 4 genera, including land-locked seal species. The transmission from seal to seal is only possible when animals are hauled-out on land or ice. Lice are rarely found on healthy adult seals, but frequently on weak and young animals. The seal louse is suggested to play an important role as an intermediate host transmitting the heartworm Acanthocheilonema spirocauda among seals. However, the evidence is restricted to a single study where the first 3 larval stages of the heartworm were shown to develop in the louse. The fourth-stage larvae develop in the blood system of seals and eventually transform into the adult stage that matures in the heart. Since all other studies failed to confirm the presence of heartworm larvae in seal lice, other unknown intermediate hosts could be involved in the transmission of the heartworm. Transplacental transmission of microfilariae in seals has been suggested as an additional possibility, but is not likely to be important since the occurrence of heartworms in adult seals is very rare compared with juveniles. Furthermore, there are no findings of the first 3 larval stages in seals. This review shows that the heartworm infects nearly the same species of seals as the seal louse, except for the grey seal Halichoerus grypus, where the heartworm is absent. Prevalence and intensity of infection differ among regions in the Northern Hemisphere. As for seal lice, heartworms mainly infect immature seals, and after infection the prevalence seems to decrease with increasing age of the host.

Ectoparasitos de roedores da regiäo urbana de Belo Horizonte, MG: III. Indices pulicidianos, anoplurianos e acarianos em Rattus Norvegicus norvegicus / Ectoparasites in rodents of the urban region of Belo Horizonte, MG: III. Fleas, anoplura and acari indices in Rattus norvegicus norvegicus

Indices pulicidianos, anoplurianos e acarianos, globais e específicos foram determinados para os ectoparasitos de Rattus norvegicus norvegicus capturados em zona urbana de Belo Horizonte, Minas Gerais, Brasil, no período de junho de 1980 a setembro de 1982. Tendo-se em vista os valores limites ou críticos atribuídos aos índices pulicidianos, sobretudo ao índice "cheopis" e propostos por diversos autores como medida complementar de vigilância epidemiológica para peste bubônica, a comunidade de Belo Horizonte poderia ter estado exposta a esta infecçäo, uma vez que os índices globais anuais de 0,3 a 2,4 e a pulga prevalente foi Xenopsylla cheopis (99,2%), com os maiores índices coincidindo com o final da estaçäo seca-fria. Em duas ocasiöes, a comunidade poderia ter permanecido altamente exposta à infecçäo, já que os índices-limites tolerados foram suplantados: 8,8 (outubro 1980) e 6,2 (setembro 1982). Sugere-se que medidas profiláticas como anti-ratizaçäo e desinsetizaçäo sejam eficazmente aplicadas ao final da estaçäo seca-fria, ou anteriormente à chegada das chuvas, sendo sucedidas pela desratizaçäo. Informaçöes sobre índices anoplurianos e acarianos säo importantes para que se possa, no exclusivas de roedores

[Lice fauna (Anoplura) of small mammals from the Charskaya Hollow]. / K faune vshei (Anoplura) melkikh mlekopitaiushchikh Charskoi kotloviny.

5 species of lice, Hoplopleura acanthopus Burm., H. longula Neum., Hoplopleura sp., Polyplax hannswrangeli Eich., Polyplax sp., were recorded from 15 species of small mammals of the Charskaya hollow, Kalarsky region, Chita district. H. acanthopus is most abundant and occurs on almost all species of small mammals.