First report of Amblyomma sculptum (Amblyomma cajennense complex) in a Brazilian state classified as a silent area for human rickettsiosis.

Background and Aim: Studies on ticks of public health concern in equine husbandry are scarce in the Northeastern region of Brazil. This study aimed to investigate the presence of ticks on horses in the State of Alagoas, which is classified as a silent area for human rickettsiosis. Materials and Methods: Ticks infesting horses were collected using anatomical tweezers or a commercial hook and kept in ethanol-labeled tubes for taxonomic identification. Results: A total of 2,238 ticks were found. Ticks were identified as 2,215 (98.89%, 95% CI: 98.41-99.28) Dermacentor nitens, 19 (0.98%, 95% CI: 0.05-1.38) Amblyomma sculptum, and 4 (0.18%; 95% CI: 0.007-0.46) Rhipicephalus microplus. Conclusion: This is the first study to report A. sculptum and D. nitens in the State of Alagoas. The presence of A. sculptum should draw the attention of public health managers once Alagoas State is considered a silent area for rickettsial diseases, which means the absence of local surveillance programs for these pathogens.

First description of clonal lineage type II (genotype #1) of Toxoplasma gondii in abortion outbreak in goats.

The purpose of this study was to perform genotypic characterization and to evaluate the virulence of Toxoplasma gondii obtained from aborted fetuses in an abortion outbreak in goats from northeastern Brazil. Brain samples from 32 fetuses were submitted to mouse bioassay for T. gondii isolation. Two isolates were obtained and subjected to genotypic characterization. Isolate virulence was evaluated using murine model in different doses (from 105 to 101 tachyzoites/mL). In genotyping, both isolates were classified as clonal lineage type II (genotype #1 ToxoDB) and showed to be virulent for mice. This is the first description of genotype #1 in cases of goat abortion, showing the circulation of virulent T. gondii isolate producing reproductive disorders in pregnant goat.

Caprine toxoplasmosis in Southern Brazil: a comparative seroepidemiological study between the indirect immunofluorescence assay, the enzyme-linked immunosorbent assay, and the modified agglutination test.

This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and compared these results with the enzyme-linked immunosorbent assay (ELISA) and the modified agglutination test (MAT). In addition, possible risk factors associated with infection due to Toxoplasma gondii were determined. The serum samples evaluated were from 1,058 goats derived from 94 goat herds within the state of Paraná, Southern Brazil. Seropositivity by IFA was 30.0%, 33.3% by ELISA, and 25.3% by MAT. The risk factors associated with infection by T. gondii in goats were pasture rental, female goats, the presence of cats, and pastures shared with several goat herds. Using IFA as a standard, ELISA and MAT showed substantial concordance (kappa = 0.74 and 0.61), with sensitivities of 87 and 66.2% and specificities of 89.7 and 92.2%, respectively. These results demonstrate that caprine toxoplasmosis is endemic within the state of Paraná, Southern Brazil. In addition, the results from the three assays were relevant, without any significant differences as demonstrated due to the substantial concordance based on the kappa index.

Toxoplasma gondii in backyard pigs: seroepidemiology and mouse bioassay.

The aim of this study was to evaluate the occurrence of Toxoplasma gondii in backyard pigs destined for human consumption in Pernambuco state, Brazil. Blood and tissue samples (liver, heart, brain, lung and diaphragm) were collected from 224 pigs from legal slaughterhouses and tested for T. gondii infection. Antibodies to T. gondii were found in the sera of 37.9% (85/224) by using the immunofluorescence antibody test (cut-off - 1:64). Tissue samples from seropositive pigs were bioassayed in mice. Tissue samples from seropositive pigs and from mice of the bioassay were submitted to histopathology, immunohistochemistry, polymerase chain reaction (PCR) and sequencing; 14.1% of pig tissue samples and 27.7% of bioassayed mouse samples were positive for T. gondii DNA, but all pig and mouse tissues were negative in histopathology analysis and immunochemistry. By using a risk assessment questionnaire, there was significant difference (p<0.001) in seroprevalence of 21.2% (reproducer) and 3.1% (finishing pig). These data serve as indicative of the sanitary conditions and risk of T. gondii infection for backyard pigs. Preventive measures must be implemented by health services to avoid toxoplasmosis human cases due to ingestion of pig meat.

Cryptosporidium spp. and Giardia spp. in feces and water and the associated exposure factors on dairy farms.

The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of Cryptosporidium was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of Giardia and Cryptosporidium was higher in calves than in adults. Among the samples of cattle feces, Cryptosporidium parvum was identified in 41 (64%), C. ryanae in eight (12.5%), C. bovis in four (6.3%), C. andersoni in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). Giardia duodenalis and C. parvum were identified in three water samples. The gp60 gene analysis of C. parvum isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. C. parvum and G. duodenalis were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment.

First isolation and RFLP genotyping of Toxoplasma gondii from crab-eating fox (Cerdocyon thous-Linnaeus, 1766).

Wild animals may play an important role in the transmission and maintenance of Toxoplasma gondii in the environment. The purpose of the present study was to isolate and genotype T. gondii from a free-ranging crab-eating fox (Cerdocyon thous-Linnaeus, 1766). A crab-eating fox in critical health condition was attended in a veterinary hospital in Recife, Pernambuco State, Brazil. The animal died despite emergency treatment. The brain was collected aseptically and destined for mouse bioassay. One isolate of T. gondii was obtained, and Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCR-RFLP) was used to assess genetic variability at 11 markers (SAG1, SAG2, altSAG2, SAG3, BTUB, GRA6, c228, c292, L358, PK1 and APICO). A murine model was used to assess the virulence of the isolate. Using the PCR-RFLP, genotype ToxoDB #13 was identified, which is considered an atypical strain. The isolate was classified as avirulent in the murine model. This is the first study to report T. gondii infection in the crab-eating fox.

Comparison of indirect fluorescent antibody test and the modified agglutination test for the detection of Toxoplasma gondii antibodies in stray dogs from Southern Brazil.

The aim of the present study was to determine the prevalence of antibodies to Toxoplasma gondii by two serological techniques in sera of 364 stray dogs from Brazil by immunofluorescence antibody test (IFAT, cut off point 1:16) and to the modified agglutination test (MAT, cut-off points 1:25 and 1:50). A total of 175/364 (48.07%) sera were positive by IFAT, and 108/364 (29.67%) and 85/364 (23.35%) were positive by MAT with cutoff points 1:25 and 1:50, respectively were positive by MAT. Cohen's Kappa Coefficient between IFAT and MAT was 0.81 (excellent) and 0.66 (substantial) with cutoff points 1:25 and 1:50, respectively. Using IFAT as gold standard, MAT sensitivity and specificity were 78% and 99% for 1:25 and 61% and 99% for 1:50, respectively. The results document of the usefulness of MAT for serological diagnosis because it does not require species-specific conjugate.

Application of different techniques to detect Toxoplasma gondii in slaughtered sheep for human consumption.

The aim of this study was to investigate occurrence of Toxoplasma gondii in sheep slaughtered in the state of Alagoas, Brazil, by means of different diagnosis techniques. Serum samples and tissues from 100 slaughtered sheep were used. To detect antibodies, the indirect immunofluorescence antibody test (IFAT) was used, and tissues from seropositive animals (cut-off ≥1:64) were submitted to Polymerase Chain Reaction (PCR) and immunohistochemistry (IHC). To assess the concordance between the direct techniques, the kappa test was used. In the IFAT, it was observed that 14% (14/100) of the ovine samples were serum-positive. In the PCR, 21.43% (3/14) of the animals were positive and in IHC, it was observed that 7.14% (1/14) were positively stained for T. gondii in cerebral tissue. Histopathologically, the predominant finding was the presence of mononuclear cell infiltrate in the heart and a perivascular cuff in the cerebrum and cerebellum. The concordance between the direct diagnosis techniques was moderate (k=0.44). Thus, it is important to use different direct techniques in diagnosing toxoplasmosis in naturally infected sheep.

First report of genotype #65 of Toxoplasma gondii in pigs.

The aim of the present study was to isolate and genotype Toxoplasma gondii from pigs slaughtered for human consumption in northeastern Brazil. Indirect immunofluorescence antibody test (IFAT) was used to screen positive pigs. Tissues samples of animals with antibody titers ≥64 were submitted to bioassay in mice. One isolate of T. gondii was obtained, and the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique, using 11 markers (SAG1, SAG2, altSAG2, SAG3, BTUB, GRA6, c228, c292, L358, PK1, and APICO), was applied to evaluate the genetic variability. DNA from reference strains was used as a positive control. By means of genetic analysis, genotype ToxoDB #65 was identified, which is considered an atypical strain. This is the first record of genotype #65 in pigs. Thus, further studies in this region are necessary to determine the genetic variability of T. gondii in pigs and possible impact on public health.