RESUMO
Tick-borne disease burdens are increasing globally, impacting mostly rural and vulnerable communities. Among the most important emerging tick-borne pathogens are the Rickettsia species within the spotted fever group (SFGR) because of their genetic diversity and high lethality rate. Colombia is highly affected by SFGR despite not being reportable diseases; thus, research and clinical management are neglected. Although some departments have demonstrated high seroprevalence rates, in others, such as Boyacá Department, seroprevalence is unknown. Rickettsioses have not been described in Boyacá since 1943, and conversations with local physicians raised suspicions of recent undiagnosed disease compatible with rickettsiosis in some rural areas of the department, warranting epidemiological investigation. Using biobanked human and canine samples from a previous 2021 vector-borne disease study in Miraflores municipality, Boyacá, we had an opportunity to unearth SFGR's exposure in the region. Samples were evaluated using IgG indirect fluorescent assays against SFGR and complemented by survey questionnaires evaluating associated factors. Findings yielded first-time SFGR serological evidence in Boyacá with a 26.5% seroprevalence among dogs and a 20.4% among humans. Human and dog seroprevalences were positively associated, suggesting the presence of domestic transmission. Owning a greater number of domestic animals (prevalence ratio adjusted for all measured factors [aPR], 1.52) and living near crop fields (aPR, 7.77) were associated with an increased likelihood of household seropositivity. Our findings are consistent with the literature in Colombia, uncovering a suspected region where the disease is endemic. Future studies are warranted to continue defining high-risk areas to determine public health intervention plans.
Assuntos
Anticorpos Antibacterianos , Doenças do Cão , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Cães , Animais , Estudos Soroepidemiológicos , Humanos , Colômbia/epidemiologia , Estudos Transversais , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Masculino , Feminino , Adulto , Anticorpos Antibacterianos/sangue , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Pessoa de Meia-Idade , Rickettsia/imunologia , Adolescente , Adulto Jovem , Idoso , Criança , Imunoglobulina G/sangueRESUMO
Introduction: Rickettsioses are zoonotic diseases transmitted by arthropods acting as vectors and reservoirs. Disease symptoms are nonspecific and, therefore, their clinical diagnosis is difficult. Indirect immunofluorescence (IFA) is the gold standard assay for diagnosis. The interest for conducting studies on these pathologies has resurfaced in Colombia since 2001; besides, previous studies have evidenced cases of rickettsiosis in the north of the department of Caldas. Objective: To establish the frequency of antibodies and seroconversion against Rickettsia spp. In patients consulting health institutions in Caldas, Colombia, from 2016 to 2019. Materials and methods: We conducted a quantitative, observational, and descriptive study on a non-probabilistic sample of 175 patients with symptoms compatible with rickettsiosis who consulted in different municipalities of Caldas, Colombia; IFA was performed to detect antibodies in the acute and convalescent phases against Rickettsia rickettsii, Rickettsia typhi, and Rickettsia felis. Results: The average age of the patients was 31 years. The municipalities with the highest proportion of seropositive cases were Belalcázar, Chinchiná, Filadelfia, La Dorada, La Merced, and Manizales; 66% of patients owned pets and 12% reported arthropod bites. The most frequent signs and symptoms were headache (69.7%), arthromyalgia (60%), and fever (58.2%). IgG seroprevalence was 60% for R. rickettsii, 47.9% for R. typhi, and, and 24% for R. felis. Eight patients presented seroconversion. Conclusion: We found evidence of the circulation of Rickettsia species from the spotted fever group and the typhus group associated with human cases in Caldas.
Introducción. Las rickettsiosis son enfermedades zoonóticas transmitidas por artrópodos que cumplen el papel de vectores y reservorios, y cuyos síntomas son inespecíficos, por lo que su diagnóstico clínico es difícil. La inmunofluorescencia indirecta (IFI) es el método de referencia para el diagnóstico. En Colombia, ha resurgido el interés por su estudio por los casos de rickettsiosis detectados en el norte del departamento de Caldas a partir del 2001. Objetivo. Establecer la frecuencia de anticuerpos y la seroconversión contra Rickettsia spp. en pacientes atendidos en instituciones de salud del departamento de Caldas, Colombia, entre 2016 y 2019. Materiales y métodos. Se hizo un estudio de diseño cuantitativo, observacional y descriptivo, con una muestra no probabilística de 175 pacientes atendidos en diferentes municipios de Caldas, a quienes se les realizó IFI para la detección de anticuerpos en fase aguda y convaleciente contra Rickettsia rickettsii, R. typhi y R. felis. Resultados. El promedio de edad de los pacientes fue de 31 años. Los municipios con mayor proporción de seropositivos fueron Belalcázar, Chinchiná, Filadelfia, La Dorada, La Merced y Manizales. El 66 % tenía mascotas y el 12 % reportó picaduras por artrópodos. Los signos y síntomas más frecuentes fueron cefalea (69,7 %), artromialgia (60 %), y fiebre (58,2 %). La seroprevalencia por IgG fue de 60 % para R. rickettsii, 47,9 % para R. typhi y 24 % para R. felis. Ocho pacientes presentaron seroconversión. Conclusión. Se encontró evidencia de la circulación de rickettsias del grupo de las fiebres manchadas y del grupo del tifus asociada con casos humanos en el departamento de Caldas.
Assuntos
Infecções por Rickettsia , Rickettsia , Adulto , Anticorpos Antibacterianos , Colômbia/epidemiologia , Humanos , Rickettsia/imunologia , Infecções por Rickettsia/epidemiologia , Soroconversão , Estudos SoroepidemiológicosRESUMO
BACKGROUND: Rickettsia bacteria are responsible for diseases in humans and animals around the world, however few details are available regarding its ecology and circulation among wild animals and human populations at high transmission risk in Brazil. The aim of this study was to investigate the occurrence of ticks and Rickettsia spp. in wild boars, corresponding hunting dogs and hunters. METHODS: Serum samples and ticks were collected from 80 free-range wild boars, 170 hunting dogs and 34 hunters from southern and central-western Brazil, from the Atlantic Forest and Cerrado biomes, respectively, between 2016 and 2018. Serum samples were tested by indirect immunofluorescent-antibody assay (IFA) to detect IgG antibodies against Rickettsia rickettsii, Rickettsia parkeri, Rickettsia bellii, Rickettsia rhipicephali and Rickettsia amblyommatis. Tick species were identified by morphological taxonomic keys, as previously described. A total of 164 ticks including A. sculptum, A. brasiliense and A. aureolatum were tested in PCR assays for Spotted Fever Group (SFG) Rickettsia spp. RESULTS: A total of 58/80 (72.5%) wild boars, 24/170 (14.1%) hunting dogs and 5/34 (14.7%) hunters were positive (titers ≥ 64) to at least one Rickettsia species. A total of 669/1,584 (42.2%) ticks from wild boars were identified as Amblyomma sculptum, 910/1,584 (57.4%) as Amblyomma brasiliense, 4/1,584(0.24%) larvae of Amblyomma spp. and 1/1,584 (0.06%) nymph as Amblyolmma dubitatum. All 9 ticks found on hunting dogs were identified as Amblyomma aureolatum and all 22 ticks on hunters as A. sculptum. No tested tick was positive by standard PCR to SFG Rickettsia spp. CONCLUSIONS: The present study was the concomitant report of wild boar, hunting dog and hunter exposure to SFG rickettsiae agents, performed in two different Brazilian biomes. Wild boar hunting may increase the risk of human exposure and consequently tick-borne disease Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.
Assuntos
Anticorpos Antibacterianos/sangue , Doenças do Cão/sangue , Cães/sangue , Infecções por Rickettsia/sangue , Infecções por Rickettsia/veterinária , Rickettsia/imunologia , Doenças dos Suínos/sangue , Carrapatos/imunologia , Animais , Animais Selvagens/sangue , Animais Selvagens/microbiologia , Brasil , Doenças do Cão/microbiologia , Cães/microbiologia , Feminino , Humanos , Masculino , Rickettsia/classificação , Rickettsia/isolamento & purificação , Infecções por Rickettsia/microbiologia , Sus scrofa/sangue , Sus scrofa/microbiologia , Suínos , Doenças dos Suínos/microbiologia , Carrapatos/classificação , Carrapatos/microbiologiaRESUMO
Rickettsia and Leptospira spp. are under-recognized causes of acute febrile disease worldwide. Rickettsia species are often placed into the spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR). We explored the antibody prevalence among humans for these two groups of rickettsiae in four regions of Peru (Lima, Cusco, Puerto Maldonado, and Tumbes) and for Leptospira spp. in Puerto Maldonado and Tumbes. We also assessed risk factors for seropositivity and collected serum samples and ectoparasites from peri-domestic animals from households in sites with high human seroprevalence. In total, we tested 2,165 human sera for antibodies (IgG) against SFGR and TGR by ELISA and for antibodies against Leptospira by a microscopic agglutination test. Overall, human antibody prevalence across the four sites was 10.6% for SFGR (ranging from 6.2% to 14.0%, highest in Tumbes) and 3.3% for TGR (ranging from 2.6% to 6.4%, highest in Puerto Maldonado). Factors associated with seroreactivity against SFGR were male gender, older age, contact with backyard birds, and working in agriculture or with livestock. However, exposure to any kind of animal within the household decreased the odds ratio by half. Age was the only variable associated with higher TGR seroprevalence. The prevalence of Leptospira was 11.3% in Puerto Maldonado and 5.8% in Tumbes, with a borderline association with keeping animals in the household. We tested animal sera for Leptospira and conducted polymerase chain reaction (PCR) to detect Rickettsia species among ectoparasites collected from domestic animals in 63 households of seropositive participants and controls. We did not find any association between animal infection and human serostatus.
Assuntos
Leptospirose/epidemiologia , Infecções por Rickettsia/epidemiologia , Adolescente , Adulto , Animais , Animais Domésticos , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Estudos Transversais , Demografia , Ecossistema , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Ectoparasitoses/veterinária , Feminino , Humanos , Lactente , Recém-Nascido , Leptospira/imunologia , Leptospirose/microbiologia , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Animais de Estimação , Rickettsia/imunologia , Infecções por Rickettsia/microbiologia , Fatores de Risco , Estudos Soroepidemiológicos , Adulto Jovem , ZoonosesRESUMO
Abstract Occurrence of infection or exposure to Ehrlichia canis, Hepatozoon canis and Rickettsia spp. was detected in feral cats living in two fragments from Atlantic rainforest, in Natal, RN, Brazil, and in dogs living around the parks. While serum samples were collected from 155 animals (53 cats living in the parks; 29 dogs living in human homes around the parks; and 73 dogs living at an animal control center - ACC), spleen samples were collected from 20 dogs that were euthanized at ACC. Serum samples were analyzed to Rickettsia spp. and E. canis antibodies using the indirect immunofluorescence assay. Seventeen of the 102 dogs (17%) had E. canis antibodies and 13% (20/155) of all dogs and cats (i.e. 3% (3/102) of the dogs and 32% (17/53) of the cats) were seropositive for Rickettsia spp. antigens. The animals were therefore been exposed to R. amblyommatis or by a very closely related genotype. Among the 20 dog spleen samples analyzed, eight were PCR positive for E. canis and two for H. canis (GenBank accession number MG772657 and MG772658, respectively). In none of the spleen samples were obtained amplicons for Babesia spp. through PCR. This study provided the first evidence that Rickettsia of the spotted fever group is circulating among dogs and cats in Natal.
Resumo A ocorrência de infecção ou exposição para Ehrlichia canis, Hepatozoon canis e Rickettsia spp. foi determinada em gatos ferais que viviam em dois fragmentos da Mata Atlântica, localizados em Natal, RN, Brasil e em cães que viviam em torno dos parques e em outras regiões da cidade. Enquanto amostras de soro foram coletadas de 155 animais (53 gatos que viviam nos parques, 29 cães com domicilio em torno dos parques e 73 cães do Centro de Controle de Animais -CCA), fragmentos de baço foram coletados de 20 cães eutanasiados no CCA. A detecção de anticorpos nas amostras de soros coletadas contra Rickettsia spp. e E. canis foi realizada pela Reação de Imunofluorescência Indireta. Dezessete dos 102 cães (17%) apresentaram anticorpos anti E. canis e 13% (20/155) de todos os cães e gatos (ou seja, 3% (3/102) dos cães e 32% (17/53) dos gatos) foram soropositivos para antígenos de Rickettsia spp. Os animais foram considerados expostos à R. amblyommatis ou a um genótipo muito relacionado. Entre as 20 amostras de baço de cães analisadas, oito foram positivas para E. canis e duas para Hepatozoon canis (números de acesso ao Genbank MG772657 e MG772658, respectivamente). Nenhuma das amostras de baço produziram amplicons de Babesia spp. na PCR. Observou-se, pela primeira vez, a circulação de Rickettsia do grupo da febre maculosa em cães e gatos em Natal, RN.
Assuntos
Animais , Gatos , Cães , Infecções por Rickettsia/veterinária , Doenças do Gato/epidemiologia , Ehrlichiose/veterinária , Coccidiose/veterinária , Doenças do Cão/epidemiologia , Rickettsia/imunologia , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/epidemiologia , Brasil/epidemiologia , Doenças do Gato/diagnóstico , Doenças do Gato/microbiologia , Doenças do Gato/parasitologia , Florestas , Eucoccidiida/imunologia , Ehrlichiose/diagnóstico , Ehrlichiose/epidemiologia , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Técnica Indireta de Fluorescência para Anticorpo , Ehrlichia canis/imunologia , Doenças do Cão/diagnóstico , Doenças do Cão/microbiologia , Doenças do Cão/parasitologiaRESUMO
Occurrence of infection or exposure to Ehrlichia canis, Hepatozoon canis and Rickettsia spp. was detected in feral cats living in two fragments from Atlantic rainforest, in Natal, RN, Brazil, and in dogs living around the parks. While serum samples were collected from 155 animals (53 cats living in the parks; 29 dogs living in human homes around the parks; and 73 dogs living at an animal control center - ACC), spleen samples were collected from 20 dogs that were euthanized at ACC. Serum samples were analyzed to Rickettsia spp. and E. canis antibodies using the indirect immunofluorescence assay. Seventeen of the 102 dogs (17%) had E. canis antibodies and 13% (20/155) of all dogs and cats (i.e. 3% (3/102) of the dogs and 32% (17/53) of the cats) were seropositive for Rickettsia spp. antigens. The animals were therefore been exposed to R. amblyommatis or by a very closely related genotype. Among the 20 dog spleen samples analyzed, eight were PCR positive for E. canis and two for H. canis (GenBank accession number MG772657 and MG772658, respectively). In none of the spleen samples were obtained amplicons for Babesia spp. through PCR. This study provided the first evidence that Rickettsia of the spotted fever group is circulating among dogs and cats in Natal.
Assuntos
Doenças do Gato/epidemiologia , Coccidiose/veterinária , Doenças do Cão/epidemiologia , Ehrlichiose/veterinária , Infecções por Rickettsia/veterinária , Animais , Brasil/epidemiologia , Doenças do Gato/diagnóstico , Doenças do Gato/microbiologia , Doenças do Gato/parasitologia , Gatos , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Doenças do Cão/diagnóstico , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Ehrlichia canis/imunologia , Ehrlichiose/diagnóstico , Ehrlichiose/epidemiologia , Eucoccidiida/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Florestas , Rickettsia/imunologia , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/epidemiologiaRESUMO
Rocky Mountain spotted fever (RMSF) is a severe tick-borne rickettsial illness. In the south-western United States and Mexico, RMSF displays unique epidemiologic and ecologic characteristics, including Rhipicephalus sanguineus sensu lato (brown dog tick) as the primary vector. Expansion and spread of the disease from hyperendemic regions of Arizona or Mexico to new areas is a key public health concern. Dogs are thought to play an important role in the emergence and circulation of R. rickettsii in these regions and are often one of earliest indicators of RMSF presence. A canine serosurvey was conducted in 2015 among owned and stray dogs at rabies clinic and animal shelters in three southern Arizona counties where RMSF had not previously been identified. Of the 217 dogs sampled, 11 (5.1%) tested positive for spotted fever group rickettsia (SFGR) IgG antibodies, with seropositivity ranging from 2.9% to 12.2% across the three counties. Large dogs were significantly more likely than small dogs to have positive titres reactive with R. rickettsii; no additional statistically significant relationships were observed between seropositivity of canine age, sex, neuter or ownership status. In addition, 17 (7.8%) dogs had ticks attached at the time of sampling, and stray dogs were significantly more likely to have ticks present than owned dogs (p < 0.001). All 57 ticks collected were identified as Rh. sanguineus s.l., and four (7%) had DNA evidence of genera-wide Rickettsia species. The results of this project demonstrated canine seroprevalence levels lower than those previously reported from dogs in highly endemic areas, indicating a low risk of SFGR transmission to humans in the southern Arizona border region at this time. Continued surveillance is critical to identify SFGR emergence in new geographic regions and to inform prevention efforts for humans and dogs in those areas.
Assuntos
Anticorpos Antibacterianos/sangue , Doenças do Cão/epidemiologia , Rickettsia/imunologia , Febre Maculosa das Montanhas Rochosas/veterinária , Infestações por Carrapato/veterinária , Animais , Arizona/epidemiologia , Doenças do Cão/sangue , Doenças do Cão/prevenção & controle , Doenças do Cão/transmissão , Cães , Humanos , México/epidemiologia , Rickettsia/isolamento & purificação , Febre Maculosa das Montanhas Rochosas/epidemiologia , Febre Maculosa das Montanhas Rochosas/imunologia , Febre Maculosa das Montanhas Rochosas/transmissão , Estudos Soroepidemiológicos , Infestações por Carrapato/epidemiologiaRESUMO
Rickettsia parkeri strain Atlantic rainforest (SAR) is the etiological agent of a spotted fever group rickettsiosis in Brazil, where it is transmitted to humans by the tick Amblyomma ovale. A previous study demonstrated that R. parkeri SAR was successfully maintained in A. ovale ticks by transstadial and transovarial passages; however, because this agent induced lower reproduction rates in A. ovale, the participation of a vertebrate amplifier host, yet to be determined, was speculated. Since the rice rat Euryoryzomys russatus was demonstrated to be the most important host for immature stages of A. ovale in a focus of R. parkeri SAR transmission, the present study evaluated the competence of rice rats to act as amplifying host of R. parkeri SAR for A. ovale ticks. Rice rats were infested with R. parkeri SAR-infected A. ovale nymphs, and four days later with uninfected A. ovale larvae. Rickettsial transmission to rats was confirmed by seroconversion to R. parkeri antigens. Detached engorged larvae were allowed to molt to nymphs, in which rickettsial DNA was detected in up to 60% (mean: 20%) of the specimens. When part of these nymphs was allowed to feed on susceptible rice rats, rickettsial transmission was confirmed by seroconversion, indicating that there was successful horizontal transmission of R. parkeri SAR from infected nymphs to uninfected larvae in the previous acquisition infestations. Because we used naïve, susceptible rats, we infer that this horizontal transmission occurred via a systemic infection (rickettsemia) in the rat. Our results, coupled with previous epidemiological studies, suggest that under natural conditions rice rats could be acting as amplifying hosts of R. parkeri SAR to A. ovale ticks.
Assuntos
Ixodidae/microbiologia , Infecções por Rickettsia/sangue , Infecções por Rickettsia/epidemiologia , Rickettsia/isolamento & purificação , Sigmodontinae/microbiologia , Sigmodontinae/parasitologia , Infestações por Carrapato/epidemiologia , Animais , Anticorpos Antibacterianos/sangue , Brasil/epidemiologia , DNA Bacteriano/genética , Transmissão de Doença Infecciosa , Larva/microbiologia , Ninfa/microbiologia , Ratos/parasitologia , Rickettsia/genética , Rickettsia/imunologia , Infecções por Rickettsia/imunologia , Infecções por Rickettsia/transmissão , Infestações por Carrapato/parasitologiaRESUMO
Spotted fevers are tick-borne diseases associated with various Rickettsia species. Rickettsia parkeri sensu stricto (s.s.) is the agent of an emerging eschar-associated rickettsiosis in humans from the USA and South American Pampa. Considering that R. parkeri s.s. is restricted to Americas and the potential role of dogs in the epidemiology of the disease, it is thus reasonable to hypothesize that wild canids could be involved in the enzootic cycle of this rickettsiosis. The aim of this work was to investigate the potential role of the wild canids from Pampa, Cerdocyon thous (crab-eating fox) and Lycalopex gymnocercus (Pampas fox), in the ecology of R. parkeri s.s. For that, 32 live-trapped free-ranging wild canids were sampled. Ticks were observed in 30 of the 32 foxes. Of the 292 ticks collected, 22 (7.5%) were positive by PCR for the presence of R. parkeri s.s. DNA. Also, 20 (62%) wild canids showed antibodies against R. parkeri. The results suggest that wild canids are involved in the enzootic cycle of R. parkeri s.s. in the Pampa biome and could be responsible for pathogen (and its vectors) dispersal.
Assuntos
Vetores Aracnídeos/microbiologia , Raposas/microbiologia , Infecções por Rickettsia/microbiologia , Rickettsia/isolamento & purificação , Doenças Transmitidas por Carrapatos/microbiologia , Carrapatos/microbiologia , Animais , Animais Selvagens , Brasil/epidemiologia , Reservatórios de Doenças/microbiologia , Ecossistema , Feminino , Raposas/imunologia , Humanos , Masculino , Reação em Cadeia da Polimerase , Rickettsia/genética , Rickettsia/imunologia , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/transmissão , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/transmissão , ZoonosesRESUMO
To determine the prevalence of antibodies to Rickettsia and Ehrlichia, related to recent and past contact, in the border towns of the departments Loreto, Madre de Dios, Tumbes and Tacna, during the years 2010 and 2011, surveys for serological evaluation were carried out using the indirect immunofluorescence assay (IIF), in order to detect immunoglobulins G (IgG) and Total immunoglobulins (IgA + IgM + IgG) in 1634 persons. A recent contact prevalence was found for Ehrlichia of 3.7% (CI 95%: 3.0-4.4) and for Rickettsia of 10.6% (CI 95%: 9.1-12.1), and past contact for Ehrlichia of 19.0% (CI 95%: 17.1-21.0) and for Rickettsia of 23.3% (CI 95%: 21.2-25.3). It is concluded that there is a higher prevalence for past contact or infection in the population studied, both for Rickettsia and Ehrlichia, which would indicate an endemic behavior to both infectious agents in the geographic areas mentioned.
Para determinar la prevalencia de anticuerpos a Rickettsia y Ehrlichia, relacionada a contacto reciente y pasado, en localidades fronterizas de los departamentos Loreto, Madre de Dios, Tumbes y Tacna, durante los años 2010 y 2011, se llevaron a cabo encuestas para evaluación serológica empleando el ensayo de inmunofluorescencia indirecta (IFI), a fin de detectar inmunoglobulinas G (IgG) e inmunoglobulinas totales (IgA+IgM+IgG) en 1634 personas. Se encontró una prevalencia de contacto reciente para Ehrlichia de 3,7% (IC95%: 3,0-4,4) y para Rickettsia de 10,6% (IC95%: 9,1-12,1), y de contacto pasado para Ehrlichia de 19,0% (IC95%: 17,1-21,0) y para Rickettsia de 23,3% (IC95: 21,2-25,3). Se concluye, que existe una mayor prevalencia para contacto o infección pasada en la población estudiada, tanto para Rickettsia como para Ehrlichia, lo cual nos estaría indicando un comportamiento endémico de ambos agentes infecciosos en las áreas geográficas mencionadas.