title: High number of asymptomatic dogs as leptospiral carriers in an endemic area indicates a serious public health concern.
abstract: Asymptomatic dogs can be potential hosts of leptospirosis. However, the extension of this phenomenon in endemic areas has not yet been clearly defined. This study is aimed at evaluating the role of asymptomatic dogs as carriers of Leptospira in an endemic area of Brazil. A total of 131 male dogs without apparent leptospirosis symptoms were included in the study based on clinical and hematologic exams. Serum and urine samples were collected for microscopic agglutination tests (MAT) and polymerase chain reactions (PCR) targeted the LipL32 gene, respectively. Forty-two dogs (32·1%) presented seroreactivity (titres ⩾100). The serogroup Icterohaemorrhagiae was predominant, representing 92·7% of the seropositive samples. Overall, leptospiral DNA was detected on 26 urine samples (19·8%). PCR positivity was more common (28·6%) on seropositive dogs than on seronegative (15·7%) ones. Nevertheless, MAT was not correlated to PCR (P > 0·05). Age was not associated with seroreactivity, but dogs older than 5 years of age had 4·07 more chances (odds ratio) of being carriers (PCR positive) than younger ones. Although the fact of knowing that asymptomatic dogs can act as leptospiral carriers is not new, the extension of this fact is impressive in an endemic region, and its role and impact on public health cannot be neglected.
authors.affiliation: Laboratory of Veterinary Bacteriology,Biomedical Institute of the Fluminense Federal University located at Rua Professor Hernani Mello,101 Niterói,Rio de Janeiro,Brazil.
authors.forename: R
authors.initials: R
authors.lastname: Sant'anna
authors.affiliation: Laboratory of Veterinary Bacteriology,Biomedical Institute of the Fluminense Federal University located at Rua Professor Hernani Mello,101 Niterói,Rio de Janeiro,Brazil.
authors.forename: A S
authors.initials: AS
authors.lastname: Vieira
authors.affiliation: Laboratory of Veterinary Bacteriology,Biomedical Institute of the Fluminense Federal University located at Rua Professor Hernani Mello,101 Niterói,Rio de Janeiro,Brazil.
authors.forename: J
authors.initials: J
authors.lastname: Grapiglia
authors.affiliation: Laboratory of Veterinary Bacteriology,Biomedical Institute of the Fluminense Federal University located at Rua Professor Hernani Mello,101 Niterói,Rio de Janeiro,Brazil.
authors.forename: W
authors.initials: W
authors.lastname: Lilenbaum
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D058345:Asymptomatic Infections / Q000453:epidemiology*; D001425:Bacterial Outer Membrane Proteins / Q000032:analysis; D001938:Brazil / Q000453:epidemiology; D004283:Dog Diseases / Q000453:epidemiology* / Q000382:microbiology; D004285:Dogs; D007919:Leptospira / Q000235:genetics / Q000502:physiology*; D007922:Leptospirosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D008074:Lipoproteins / Q000032:analysis; D008297:Male; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D011634:Public Health; D017422:Sequence Analysis, DNA / Q000662:veterinary; D016036:Seroepidemiologic Studies
chemical_list: D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; C406589:LipL32 protein, Leptospira; D008074:Lipoproteins
keywords: 
                 Leptospira
              ; Carriers; dog