Seroprevalence and risk factors of bovine herpesvirus 1 infection in cattle herds in the state of Paraná, Brazil

Epidemiological data describing bovine herpesvirus 1 (BoHV-1) infection in Brazilian cattle herds are scarce. A cross-sectional study was conducted in the state of Paraná between December 2001 and July 2002 with the objective of estimating the apparent prevalence of BoHV-1-seropositive herds and animals and identifying the potential risk factors for infection in farms with breeding animals in the state of Paraná in Southern Brazil. The state was divided into seven regions based on the livestock production dynamics of the different areas. Sampling was performed in two stages. Initially, herds were randomly selected, followed by a random selection of animals within the selected herds. Blood samples were collected from 14803 females, aged ≥24 months, from 2018 BoHV-1 non-vaccinated herds. Serum samples were tested for antibodies against BoHV-1 using an indirect enzyme-linked immunosorbent assay (ELISA). The apparent prevalence of seropositivity in the herds and animals in Paraná was 71.3% (95% CI: 69.3-73.3) and 59.0% (95% CI: 56.2-61.8), respectively. Multiple logistic regression analysis revealed that risk factors associated with the presence of the infection were as follows: beef herds [OR = 1.58 (1.12-2.23)], natural service [OR = 1.48 (1.02-2.14)], purchase of animals [OR = 1.90 (1.52-2.37)], pasture rental [OR = 2.24 (1.51-3.33)], existence of calving pens [OR = 1.56 (1.20-2.03)] and records of abortion in the last 12 months [OR = 1.45 (1.08-1.95)]. These results indicate that BoHV-1 infection is widespread in the state of Paraná.

Identification of Mycobacterium avium genotypes with distinctive traits by combination of IS1245-based restriction fragment length polymorphism and restriction analysis of hsp65

One-hundred eight Mycobacterium avium isolates from pigs, humans, birds, and bovines were typed by the IS1245-based restriction fragment length polymorphism (RFLP) method and PCR-restriction enzyme analysis (PRA) of hsp65. Nine clusters of isolates showing more than 80% similarity in their RFLP profiles were detected. The largest cluster (cluster B) included 32 of 79 pig isolates (40.5%), 3 of 25 human isolates (12%), and 1 of 2 bovine isolates, comprising 33% of all isolates. The second largest cluster (cluster A) included 18 pig isolates (22.8%) and 6 human isolates (24%). Six smaller clusters included six pig isolates (clusters C and D), four and two human isolates (clusters E and F, respectively), two pig isolates (cluster I), and two pig isolates plus one bovine isolate and the avian purified protein derivative strain (cluster H). Cluster G represented the "bird-type" profile and included the bird isolate in this series, one pig isolate, plus reference strain R13. PRA revealed four allelic variants. Seventy-seven isolates were identified as M. avium PRA variant I, 24 were identified as M. avium PRA variant II, 6 were identified as M. avium PRA variant III, and 1 was identified as M. avium PRA variant IV. Except for three isolates from cluster B, each of the RFLP clusters was associated with a single PRA pattern. Isolates with unique (nonclustered) RFLP profiles were distributed between PRA variants I and II, and there was one unique isolate of PRA variant IV. These observations are consistent with divergent evolution within M. avium, resulting in the emergence of distinct lineages with particular competence to infect animals and humans.

Prevalence of Toxoplasma gondii antibodies in sera of domestic cats from Guarulhos and São Paulo, Brazil

Antibodies to Toxoplasma gondii were determined in serum samples of 502 domestic cats from Brazil by the modified agglutination test (MAT), using formalin-fixed whole tachyzoites and mercaptoethanol. Antibodies (MAT > or = 1:20) were found in 132 (26.3%) of 502 cats. With respect to origin, antibodies were found in 26.7% of 430 stray cats from São Paulo, 10% of 40 stray cats from Guarulhos, and 40.6% of 32 cats from a cat breeder in São Paulo. Antibody titers were: 1:20 in 10 cats, 1:25 in 40 cats, 1:50 in 73 cats, and > or = 1:500 in 9 cats. Exposure rates of T. gondii in cats from São Paulo, Brazil are similar to that in domestic cats in North America.

Seroprevalence of Toxoplasma gondii in captive neotropical felids from Brazil

Seroprevalence of Toxoplasma gondii was determined in 865 captive neotropical felids from 20 states from Brazil, sampled from September 1995 to April 1997. Sera were tested by the modified agglutination test (MAT) using formalin-fixed whole tachyzoites and mercaptoethanol. Antibodies (MAT> or =1:20) to T. gondii were found in 472 of 865 (54.6%) cats: in 45 of 99 (45.9%) jaguarundis (Herpailurus yagouaroundi), in 97 of 168 (57.7%) ocelots (Leopardus pardalis), in 68 of 131 (51.9%) oncillas (L. tigrinus), in 35 of 63 (55.5%) margays (L. wiedii), in 1 of 8 (12.5%) Pampas-cat (Oncifelis colocolo), in 9 of 12 (75.0%) Geoffroys-cat (O. geoffroyi), in 134 of 212 (63.2%) jaguars (Panthera onca), and in 83 of 172 (48.2%) pumas (Puma concolor). Antibody titers were: 1:20 in 27 felids, 1:25 in 142 felids, 1:40 in 6 felids, 1:50 in 292 felids, and > or =1:500 in 5 felids. The high seroprevalence of T. gondii antibodies found in the present study suggested a widespread exposure of neotropical cats to T. gondii in zoos in Brazil. The results warrant an investigation on the mode of exposure and oocyst shedding by neotropical cats.

Toxoplasma gondii antibodies in exotic wild felids from Brazilian zoos

Serum samples from 37 captive exotic felids in 12 zoos from six Brazilian states were assayed for antibodies to Toxoplasma gondii by the modified agglutination test using formalin-fixed whole tachyzoites. Titers greater than or equal to 1:20 were considered positive. Antibodies to T. gondii were found in 24 of 37 (64.9%) felids, including one European lynx (Lynx lynx), two jungle cats (Felis chaus), two servals (Leptailurus serval), two tigers (Panthera tigris), three leopards (Panthera pardus), and 14 of 27 lions (Panthera leo). This is the first serologic analysis for T. gondii infection in exotic wild felids from Brazilian zoos.

Identification of two novel Mycobacterium avium allelic variants in pig and human isolates from Brazil by PCR-restriction enzyme analysis

Mycobacterium avium complex (MAC) is composed of environmental mycobacteria found widely in soil, water, and aerosols that can cause disease in animals and humans, especially disseminated infections in AIDS patients. MAC consists of two closely related species, M. avium and M. intracellulare, and may also include other, less-defined groups. The precise differentiation of MAC species is a fundamental step in epidemiological studies and for the evaluation of possible reservoirs for MAC infection in humans and animals. In this study, which included 111 pig and 26 clinical MAC isolates, two novel allelic M. avium PCR-restriction enzyme analysis (PRA) variants were identified, differing from the M. avium PRA prototype in the HaeIII digestion pattern. Mutations in HaeIII sites were confirmed by DNA sequencing. Identification of these isolates as M. avium was confirmed by PCR with DT1-DT6 and IS1245 primers, nucleic acid hybridization with the AccuProbe system, 16S ribosomal DNA sequencing, and biochemical tests. The characterization of M. avium PRA variants can be useful in the elucidation of factors involved in mycobacterial virulence and routes of infection and also has diagnostic significance, since they can be misidentified as M. simiae II and M. kansasii I if the PRA method is used in the clinical laboratory for identification of mycobacteria.