Leishmania (Viannia) shawi sp. n., a parasite of monkeys, sloths and procyonids in Amazonian Brazil

Leishmania (Viannia) shawi sp. n., is described from the monkeys Cebus apella and Chiropotes satanus, the sloths Choloepus didactylus and Bradypus tridactylus, the procyonid Nasua nasua, and the phlebotomine sandfly Lutzomyia whitmani, all from primary forest in the State of Pará, north Brazil. L. (V.) shawi is variably distinguished from all other known species within the subgenus Viannia by a combination of biological, biochemical and serological characters, as revealed by studies on morphology, isoenzyme profiles, kDNA buoyant densities and monoclonal antibodies.

Vertebrate hosts and vectors of Trypanosoma rangeli in the Amazon Basin of Brazil

A total of 46 Trypanosoma rangeli stocks were isolated from naturally infected mammals and triatomine vectors. Twenty-two stocks were from the common opossum (Didelphis marsupialis), one from the brown "4-eyed" opossum (Metachirus nudicaudatus), one from the anteater (Tamandua tetradactyla), one from the coati (Nasua nasua), seven from Rhodnius pictipes and 14 from Rhodnius robustus. Two stocks were also isolated from recently fed sandflies (Lutzomyia sp., Shannoni group). The stocks were identified as T. rangeli on the basis of natural or experimental salivary gland infections in Rhodnius, inoculative (anterior station) transmission to mice, morphological parameters in parasitemic mice and comparisons of isozyme profiles with a known stock of T. rangeli isolated from man. Three other trypanosome stocks from D. marsupialis, T. tetradactyla and the three-toed sloth (Bradypus tridactylus) were morphologically similar to T. rangeli in culture but had quite different isozyme profiles and were not identified. It is concluded that T. rangeli is widely distributed in Amazonas, Pará and Rondonia States of Brazil, and probably extends into other regions where R. pictipes and R. robustus are known to occur. R. pictipes is light-attracted into houses and occasionally transmits Chagas' disease to man. It is likely that T. rangeli is also occasionally transmitted to man in the Amazon basin.

Ecologic correlates of Toxoplasma gondii exposure in free-ranging neotropical mammals

A serologic survey for Toxoplasma gondii in 18 free-ranging forest mammal species (n = 456) in French Guiana was undertaken with a direct agglutination test. Serum antibody prevalence varied from 0-71%. The relationships between ecologic features of the species and seroprevalence were investigated. Terrestrial mammals were significantly more exposed to T. gondii than other mammals. This result is concordant with oral exposure to T. gondii related to ground dwelling behavior and/or carnivory.

Leishmania (Viannia) naiffi sp. n., a parasite of the armadillo, Dasypus novemcinctus (L.) in Amazonian Brazil

A new leishmanial parasite, Leishmania (Viannia) naiffi sp. n., is described from the nine-banded armadillo, Dasypus novemcinctus (Edentata: Dasypodidae), from Para State, north Brazil. The parasite grows luxuriantly in Diffco blood-agar medium (B47), but poorly in the skin of intradermally inoculated hamsters. A comparison of isoenzyme profiles by starch gel electrophoresis separates the parasite from L. (V) braziliensis and L. (V.) guyanensis by the enzymes ASAT, ALAT, PGM, GPI, G6PD, PEP, MPI and GD, and from Leishmania (Leishmania) chagasi, L. (L.) amazonensis and L. (L.) deanei by ASAT, ALAT, PGM, GPI, MPI, G6PD, MDH, PEP and ACON. Finally, L. (V.) naiffi is serologically differentiated from L. (V.) braziliensis, L. (V.) guyanensis and L. (V.) panamensis on monoclonal antibodies specific for these parasites.

The prevalence of Trypanosoma cruzi infection in armadillos collected at a site near New Orleans, Louisiana

A study was made of the prevalence of Trypanosoma cruzi infection in armadillos at a site near New Orleans, Louisiana, where the flagellate was known to occur. Blood cultures, microscopic examination of blood, and direct agglutination tests on sera were employed in 80 armadillos. T. cruzi was isolated in culture from 23 of 80 animals; identity of the parasite was confirmed in mice inoculated with each of the isolates. Only 2 animals were positive by direct examination of blood. Serologic evidence of infection was obtained for the 23 animals that were positive by culture, and for at least 7 of those animals with negative or contaminated cultures. These results suggest that the armadillo is a reservoir of this zoonosis.

Echinococcus infections in Colombian animals

The results of a survey involving more than 4,000 Colombian mammals, carried out to detect Echinococcus infections, are presented. Adult worms were found in 5 of 121 carnivores: E. oligarthrus in 1 of 11 ocelots, 2 of 9 jaguarundi cats and single puma; and E. vogeli in 1 of 15 domestic dogs. Although bush dogs were present, none could be examined. Polycystic larvae were found in 96 of 325 pacas (29.5%) and in 6 of 1,168 (0.5%) spiny rats, Proechimys spp. None of the 118 agouti showed hydatids but an infected heart was provided by hunters. The paca's infection rate increased with age but was not related to sex or geographic region. In 73 of 96 pacas the infection was due to E. vogeli, and the cysts were located in the liver. In 3 it was due to E. oligarthrus and the hydatids were extrahepatic, mainly attached to muscles. In the remaining 20, the species involved could not be determined. The parasites in two of the spiny rats, and in the agouti heart were E. oligarthrus. Although most of the infected animals were collected in the eastern plains, other records and verbal information indicate that, at least in Colombia where man has not exterminated pacas, agoutis, wild canids and felids, one still can find enzootic neotropical Echinococcus infection. The cycle of E. vogeli involves the bush dog and paca as hosts, and that of E. oligarthrus, the paca, agouti, spiny rat, and several species of wild felids.

Hosts of sandfly vectors of Leishmania braziliensis guyanensis in the central Amazon of Brazil

The blood meals of 2,569 phlebotomine sandflies from areas endemic for cutaneous leishmaniasis in the central Amazon of Brazil were tested by the microcapillary precipitin method to determine their vertebrate hosts. The two-toed sloth, Choloepus didactylus, was the predominant host of two incriminated vectors of Leishmania braziliensis guyanensis in the region, Lutzomyia umbratilis and Lu. anduzei (64.0% and 63.6%, respectively). The Lu. "shannoni" group, a complex of several species in which females are indistinguishable, also fed predominantly on sloths (73.0%). Species comprising the Lu. "shannoni" group have not been implicated as vectors of leishmaniasis; however, their feeding patterns in the study area illustrate their potential involvement in the transmission of the parasites to two-toed sloths, which are the principal reservoir hosts of L. braziliensis in Panama. Rodents, and particularly porcupines, were the second most frequently fed-on mammal by Lu. umbratilis (11.6%) and the Lu. "shannoni" group (8.5%).

Clinical disorders observed in anteaters (Myrmecophagidae, Edentata) in captivity

The major health problems found in 103 captive lesser anteaters (Tamandua tetradactyla) and giant anteaters (Myrmecophaga tridactyla), family Myrmecophagidae, are presented and correlated with management. The most common of 200 recorded clinical disorders involved the digestive system (26%), nutritional deficiency (20%), injury (15.5%), respiratory system (10%), skin (7%) and circulatory system (4.5%), but 13% of the cases were inconclusive. Parasites were identified in 48.5% of faecal samples, mainly the eggs of nematodes (40%), of which the commonest were Trichuris spp (28%) and Strongyloides spp (11%); protozoa (16%), of which the commonest were Eimeria spp (10%), Entamoeba spp (5%) and Giardia spp (1%); and cestodes (8%) and acanthocephalids (1%). Bacteria cultured from the various materials included Salmonella enteritidis, S. cholerasuis, Escherichia coli, Enterobacter aerogenes, Streptococcus spp and Staphylococcus spp. The ectoparasites found were Amblyomma spp and Otodectis spp (Arthropoda, Acaridae).

The tree-buttress biotope: a pathobiocenose of Leishmania braziliensis

A total of 52,033 sandflies, comprising 33 species, was collected in tree buttresses in Panama. Of the 18,025 females collected, 1,592 (8.8%) engorged phlebotomines of 18 species contained sufficient blood for identification of their vertebrate hosts by the microcapillary precipitin method. Lutzomyia ylephiletor and Lu. trapidoi, vectors of Leishmania braziliensis, had fed predominantly on sloths (47.0% and 65.1%, respectively). Lutzomyia shannoni, a common non-anthropophilic sandfly in tree buttresses also fed most frequently on sloths (28.0%) and probably also contributes to the Leishmania transmission cycle among the edentates. Two-toed sloths (Choloepus hoffmanni), the principal reservoir of L. braziliensis in Panama, cohabit the same arboreal bioptope with these sandfly species. Leishmania braziliensis was isolated in culture from 14 of 68 (20.6%) C. hoffmanni captured in the study sites during the period of this investigation. The data illustrate that the butrresses of large trees in Panama represent potential pathobiocenose bioptopes of L. braziliensis. Other sandfly species tested for host-feeding sources included: Lu. trinidadensis, which fed preferentially on reptiles; Lu. triramula, Lu. ovallesi, and Lu. camposi fed most frequently on armadillos. The hosts of 11 additional sandfly species were identified; however, the numbers recorded were too small to discern distinct feeding patterns among the phlebotomines.

Leishmania braziliensis in the Panamanian two-toed sloth, Choloepus hoffmanni

A total of 498 two-toed sloths, Choloepus hoffmanni, collected in central Panama was examined for Leishmania braziliensis over a 10-year period. Isolations of the parasite from 96 (19.3%) of the animals were confirmed by culture and inoculation of golden hamsters. Improved culture techniques developed toward the end of the study assisted in determining a greater prevalence of the disease. Infectins were completely cryptic in all animals, and the parasite was isolated from skin, blood, liver, spleen, bone marrow and lung tissues. Sloths maintained under seminatural conditions remained infected up to 23 months, the longest period of survival. This edentate, considered the principal reservoir host of L. braziliensis in Panama, showed infection rates from 0-59.4% in various communities, which appeared to correlate with the parasite prevalence in the indigenous human populations.

Pneumocystis carinii infections in zoo animals

Pneumocystis carinii was found to be present in the lungs of twenty-three zoo animals in the Netherlands. The following species were represented: red kangaroo, common tree shrew, Senegal-Galago, Demidoff's-Galago, brown howler monkey, woolly monkey, long-haired spider monkey, white-eared marmoset, chimpanzee, three-toed sloth, palm squirrel, red panda, fennec fox, tree hyrax and large-toothed hyrax.

Ticks associated with armadillo (Euphractus sexcinctus) and anteater (Myrmecophaga tridactyla) of Emas National Park, State of Goias, Brazil

This study was conducted in October 1998 and November 1999 in the Emas National Park (131,868 ha), a savanna-type cerrado region situated in the far south of Goias State, Brazil, near the geographic center of South America (15 degrees -23 degrees S; 45 degrees -55 degrees W). Animals were captured with the aid of nets and anesthetized (15 mg/kg ketamine + 1 mg/kg xylasine) in order to collect ticks for identification and to establish laboratory colonies. They included giant anteaters (Myrmecophaga tridactyla) (n = 4) and yellow armadillos (Euphractus sexcinctus) (n = 6). Free-living ticks (larvae, nymphs, and adults) were collected from the field by using a 1 x 2-m flannel cloth. Free-living ticks were identified as Amblyomma sp., A. cajennense, and A. triste. Adult ticks collected from anteaters were identified as Amblyomma cajennense and A. nodosum and from armadillos as A. pseudoconcolor and A. nodosum. The relevance of these host-tick relationships to possible mechanisms underlying emergence of tick-borne pathogens of importance to public health is discussed.

Tapeworms of the Chaco Boreal, Paraguay, with two new species

Mathevotaenia paraguayae sp. n. is described from Euphractus sexcinctus. It differs from M. didelphidis (Rud.) in having a transverse cirrus pouch anterior to the vagina. Monoecocestus mackiewiczi sp. n. was found in Phyllotis sp. It differs from M. parcitesticulatus Rego in having a much smaller scolex, a poral ovary, and a cirrus pouch 360 to 440 micrometers long. Other species reported are Taenia macrocystis, Taenia omissa, Spirometra mansonoides, Spirometra gracilis, Spirometra longicollis, Diphyllobothrium trinitatis, Atriotaenia parva, and Mathevotaenia tetragonocephala.

Isolation of Leishmania species from wild mammals in French Guiana

Between 1981 and 1987, 486 wild mammals collected from 13 sites in French Guiana were examined for Leishmania. Eleven of 31 two-toed sloths, Choloepus didactylus, were infected, 4 of the isolates being identified as L. braziliensis guyanensis. This species was also found in 2 Didelphis marsupialis and 2 Proechimys sp. L. mexicana amazonensis was isolated from 3 Proechimys sp., 2 of which were P. cuvieri. The role of these mammals in the life cycles of the 2 anthropotropic species of Leishmania encountered in French Guiana is discussed.

The isolation of Leishmania braziliensis from sloths in Costa Rica

Eight out of 47 Bradypus griseus and 14 out of 18 Choloepus hoffmanni yielded positive cultures for flagellates from blood, skin, liver or spleen. In some cases, more than one species of flagellate was isolated from one animal or site. Although amastigotes were obtained in tissue cultures from several isolates containing different types of promastigotes, only four of these strains (two from each species of host) were infective for hamsters and considered as Leishmania braziliensis. Infection with one of the strains was possible only after it has been passed through tissue culture.

Monoclonal antibodies specific for members of the genus Endotrypanum

Twenty-six monoclonal antibodies were produced against membrane-enriched preparations of Endotrypanum schaudinni or Endotrypanum sp. promastigotes. Fifteen of these monoclonal antibodies (E1-E15) reacted only with the standard strain of E. schaudinni, M6159. Monoclonal antibodies E16-E26 were considered Endotrypanum specific; no cross reactivity was detected with any other genus of the family Trypanosomatidae (Leishmania, Trypanosoma, Leptomonas, Herpetomonas or Crithidia) by dot-blot radioimmune assay. By indirect immunofluorescence assay, the antigens recognized by Endotrypanum specific monoclonal antibodies appear to be associated with the surface of the parasite. Based on Western blot analysis, 4 antigenic molecules ranging in molecular weight from 24 kD to 160 kD were identified by monoclonal antibodies specific for the strain of E. schaudinni, M6159. Monoclonal antibodies specific for the genus Endotrypanum identified an antigen of molecular weight 48 kD as well as a diffuse component migrating with an apparent molecular weight of 64-200 kD.

New host and distribution record of Amblyomma javanense (Acari: Ixodidae) in Thailand

Amblyomma javanense (Supino) was collected from a Malayan pangolin (Manis javanica Desmarest) and a wild boar (Sus scrofa L.) from Tak province on the western boundary of Thailand along the Myanmar (Burma) border. To date, this tick species has not been recorded from this area and from a wild boar.

Leishmaniasis in Brazil: XVII. Enzymic characterization of a Leishmania from the armadillo, Dasypus novemcinctus (Edentata), from Pará State

A comparison of enzyme profiles, by starch-gel electrophoresis, has distinguished a Leishmania of armadillos (Dasypus novemcinctus), from Pará State, north Brazil, from Leishmania braziliensis braziliensis, L. braziliensis guyanensis, L. mexicana amazonensis, L. donovani sensu lato (from Bahia, Brazil), and L. hertigi deanei. The parasite was separated from L. b. braziliensis and L. b. guyanensis by 8 of the 14 enzymes used (ASAT, ALAT, PGM, GPI, G6PD, PEP, MPI and GD), although differences in the mobility of some of the enzymes were small. At least 9 of the enzymes separated the organism from L. m. amazonensis, L. donovani s.l., and L. h. deanei.

Epidemiology of a natural focus of Leishmania braziliensis in the Pacific lowlands of Colombia. III. Natural infections in wild mammals

A natural infection of Leishmania braziliensis panamensis in the edentate, Choloepus hoffmanni is recorded from the Pacific Coast of Columbia.

Dilated cardiomyopathy and amebic gastritis in a giant anteater (Myrmecophaga tridactyla)

An approximately 11-mo-old female giant anteater (Myrmecophaga tridactyla) exhibited anorexia, lethargy, hypothermia, depression, and minimal response to external stimuli. Radiography and ultrasonography revealed an enlarged heart, with free gas and fluid in the abdomen. Abdominocentesis produced a clear brown fluid with an acute to subacute septic suppurative exudate. Cardiac ultrasonography revealed a dilated, thin-walled left ventricle with a comparatively low fractional shortening. Despite intensive supportive care, the anteater died. Postmortem findings included gastric ulceration with perforation near the pylorus. Entameba spp. and Acanthamoeba spp. were both identified in large numbers at the site of the gastric ulceration and perforation.

Microscopic features of tick-bite lesions in anteaters and armadillos: Emas National Park and the Pantanal region of Brazil

The naturally occurring wildlife host associations between ticks and tick-borne pathogens found in the neotropics are poorly described. Understanding tick-bite lesions is important as these are the site of host reaction to and pathogen delivery by ticks. As part of a comprehensive study concerning established and emerging tick-host relationships. the present work describes some aspects of tick-bite lesions in anteaters and armadillos captured at the Emas National Park and the Pantanal region of Brazil. Biopsies were of skin were taken and examine. Tick feeding sites of all animals displayed an eosinophilic homogeneous mass, the cement cone, and, occasionally, a feeding cavity underneath the tick attachment site. At these locations the epidermis was usually thickened due to keratinocyte hyperplasia. The main dermal changes included tissue infiltration with a varying number of inflammatory cells, edema, hemorrhage. and vascular dilatation. Cellular infiltration of the dermis was predominantly composed of mononuclear cells, neutrophils. and eosinophils. Mast cells were also seen in both non-parasitized and parasitized skin but were found in higher numbers at perivascular sites and in parasitized skin. Basophils were not seen at tick attachment sites of anteaters or armadillos.

On a new nematode Leipernema leiperi n.g., n.sp. (Strongyloididae), parasitic in the pangolin Manis pentadactyla from Hyderabad, India

Leipernema leiperi n.g., n.sp. is described from the pangolin Manis pentadactyla in India. Both parasitic free-living generations have been examined. Features which differentiate the parasite from Strongyloides and Parastrongyloides are described.