Infection of SARS-CoV-2 in domestic dogs associated with owner viral load.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive pet owners are reported to be a risk factor for infection of their pets; however, the influence of the viral load and associated risks has not been fully established. This study aimed to assess potential association of viral load in owners with the presence of SARS-CoV-2 infection in their dogs. Of 20 SARS-CoV-2-positive pet owners from 13 families in Curitiba, Brazil, 5 of 22 (22.7%) dogs were positive for SARS-CoV-2. Viral presence was detected in oropharyngeal samples for 2 of 5 (40.0%) dogs at 8 and 9 days after the first positive sample. Detection of SARS-CoV-2 in these dogs was associated with higher viral loads in the owners and close owner contact. All 5 RT-qPCR-positive dogs had antibodies to at least one viral protein tested in the serological assay. Molecular detection of SARS-CoV-2 in dogs was statistically associated with clinical signs in owners such as cold, cough, or diarrhea (P = 0.039), number of positive persons in the household (P = 0.002), and higher viral load (P = 0.039). Such findings serve as a warning for risks of human to dog infection, mainly due to sharing beds and other close interactions without protection. In conclusion, people with coronavirus disease 2019 (COVID-19), particularly in households with multiple residents and high viral load, should take the same preventive measures when interacting with their dogs during self-isolation as they do with people.

Seropositivity of Anti-Toxoplasma gondii Antibodies in Owners and Their Dogs Living on Island and Mainland Seashore Areas of Southern Brazil.

Although toxoplasmosis has been considered among the most neglected zoonoses worldwide, no study has focused on the frequency and associated risk factors of owners and their dogs living on an island and mainland seashore areas. Accordingly, anti-Toxoplasma gondii IgG antibodies were screened by indirect fluorescent antibody test (IFAT) in owners and dogs from three oceanic islands and two nearby mainland harbor areas, with associated risk factors for toxoplasmosis assessed by univariable and multivariable logistic regression models. Overall, anti-T. gondii seropositivity was observed in 59/328 (18.0%) owners and 66/283 (23.3%) dogs, with no statistical difference between owners (p = 0.360) and dogs (p = 0.655) from islands and mainland areas. Consumption of local water springs (p = 0.016; OR = 2.11) was an associated risk factor for T. gondii seropositivity, and owners with the habit of spring water intake were twice more likely seropositive (p = 0.014; OR = 2.14). Presence of anti-T. gondii antibodies in dogs was associated with seropositive owners (p = 0.008; OR = 2.81), household consumption of beef meat (p = 0.042; OR = 1.7) and chicken (p = 0.026; OR = 2.9). Despite being lower than the worldwide prevalence, toxoplasmosis seropositivity in owners and their dogs in southern Brazil was influenced by the positive owner, water source, and meat consumption, and not by inhabiting islands or seashore mainland areas, presence of dogs, cats, or both. In addition, drinking water quality should always be considered a critical risk factor for toxoplasmosis on islands.

Hemotropic mycoplasmas (hemoplasmas) in wild boars, hunting dogs, and hunters from two Brazilian regions.

Haemotropic mycoplasmas (haemoplasmas) are small pleomorphic bacteria infecting erythrocytes of several mammalian species, including human beings. No study to date has focused on the risk of bacteria exposure in hunting activities, particularly in natural environments of highly tick-infested areas. Accordingly, the present study aimed to assess haemoplasma occurrence in the complex encompassing wild boars, hunting dogs and hunters of Brazil. A total of 38/65 (58.5%) wild boars and 94/159 (59.1%) dogs were positive by qPCR for at least one haemoplasma. All 25 hunters were negative. Dogs with high hunting frequency were 2.4 more likely to be infected. Sequencing revealed a probable novel haemoplasma species in wild boars. Although exposure to haemoplasma species was present, the study herein found no evidence of cross-species transmission.

One Health approach on human seroprevalence of anti-Toxocara antibodies, Toxocara spp. eggs in dogs and sand samples between seashore mainland and island areas of southern Brazil.

Toxocariasis, caused by Toxocara spp. nematodes, is among the top 5 neglected parasitic diseases worldwide; however, no comprehensive study to date has serologically compared infections in people and their dogs and environmentally contaminated soil or sand of mainland and island locations. Accordingly, this study aimed to assess the seroprevalence of anti-Toxocara antibodies in traditional human seashore populations, the presence of eggs in dogs' feces and hair, and the presence of eggs in environmental samples from islands compared to the adjacent mainland of southern Brazil. Overall, 212/328 (64.6%) people were positive for Toxocara spp. antibodies, including 125/190 (65.8%) island and 87/138 (63.0%) mainland residents. For dog samples, 12/115 (10.43%) were positive for the presence of Toxocara spp. eggs, all from dogs living in islands, and 22/104 (21.15%) dog hair samples contained eggs of Toxocara spp. Environmental contamination with Toxocara spp. eggs was observed in 50/130 (38.46%) samples from all sampled sites. No significant association was found between risk factors (age, sex, educational level, monthly income, owning dogs or cats, ingestion of treated water, and consumption of raw or uncooked meat) and Toxocara spp. seropositivity. The present study is the first concurrent report on people, their dogs, and environmental contamination of Toxocara spp. The high prevalence we observed in the seashore populations of both in island and mainland areas may be caused by exposure to contaminated sand and climatic factors favoring frequent exposure to Toxocara spp. In conclusion, seashore lifestyle and living conditions of both island and mainland areas may have predisposed higher contact with infected pets and contaminated soil, favoring the high prevalence of toxocariasis.

Serosurvey of anti-Leishmania (Leishmania) infantum antibodies in hunting dogs and hunters in Brazil.

BACKGROUND AND AIM: Although wild boar hunting activities and the hunting dog trade in the Atlantic Forest and Cerrado biomes of Brazil overlap both with endemic and with non-endemic areas for visceral leishmaniasis, no study to date has focused on Leishmania spp. exposure among hunting dogs and hunters. The aim of the present study was to assess the presence of Leishmania spp. antibodies in hunting dogs and hunters in different anthropized areas of two Brazilian biomes. MATERIALS AND METHODS: Blood samples were collected from 170 hunting dogs and 46 hunters between October 2016 and May 2018. The presence of antibodies against Leishmania spp. in hunting dogs was screened through a dual-path platform immunochromatographic test (DPP rapid test; Bio-Manguinhos/Fundação Oswaldo Cruz, Rio de Janeiro, Brazil) and in hunters through an rK39-based rapid immunochromatographic test. Both tests were used in accordance with Brazilian Ministry of Health recommendations. RESULTS: Overall, although antibodies were detected through the immunochromatographic test in 3/170 (0.02%) of these female asymptomatic hunting dogs, all living in anthropized areas of the Atlantic Forest biome in South Brazil, no sample was confirmed through the enzyme-linked immunosorbent assay. All the hunters were non-reactive in the rapid immunochromatographic test. CONCLUSION: Our study on three suspicious hunting dogs has suggested that Leishmania (Leishmania) infantum may circulate both in endemic and non-endemic areas in Brazil. In addition, a high rate of hunting dog replacement due to death and trade may have led to less chance of infection and transmission between animals and between animals and humans, which would corroborate the outcomes reported here. Further studies should be conducted to fully establish whether hunting dogs and hunters may be used as sentinels in other areas endemic for Leishmania spp.

From the Approach to the Concept: One Health in Latin America-Experiences and Perspectives in Brazil, Chile, and Colombia.

Professionals throughout the world have been working to assess the interdisciplinary interaction and interdependence between health and wellbeing in a constantly changing environment. The One Health concept was developed to encourage sustainable collaborative partnerships and to promote optimal health for people, animals, plants, the environment, and the whole planet. The dissemination of scientific discoveries and policies, by working directly with diverse communities, has been one of the main goals for Global One Health. The One Health concept has also been referred or related to as "One Medicine, One Medicine-One Health, One World-One Health, EcoHealth," and Planetary Health," depending on each fundamental view and approach. In Latin America, despite the concept still being discussed among health professionals and educators, several One Health initiatives have been used daily for more than decades. One Health action has been applied especially in rural and underserved urban areas where low socioeconomic status, lack of health professionals, and scarcity of medical resources may require professionals to work together. Local communities from diverse social and economic statuses, including indigenous populations have been working with institutions and social organizations for many years, accomplishing results through grassroots movements. These "bottom-up" socio-community approaches have also been tools for the prevention and control of diseases, such practice has preceded the One Health concepts in Latin American countries. It is strongly believed that collaborative, multidisciplinary, political, and economic initiatives with prosocial focus may become investments toward obtaining significant results in the face of global, economic and health challenges; working for a healthier world with inclusivity, equity, and equality. In this study, it is briefly presented how the One Health approach has been initiated and developed in Latin America, highlighting the events and actions taken in Brazil, Chile, and Colombia.

Social Sciences in One Health: Insights From Multiple Worlds Perspectives on the Dam Rupture in Brumadinho-Brazil.

Concepts that integrate human, animal, and ecosystem health - such as One Health (OH) - have been highlighted in recent years and mobilized in transdisciplinary approaches. However, there is a lack of input from the social sciences in OH discussions. This is a gap to overcome, including in Latin America. Therefore, this paper incorporates recent studies from economics and anthropology to the debate, contributing to the opening of transdisciplinary dialogues for the elaboration of OH theory and practice. As a starting point, we explore the recent case of a tailings dam breach, making considerations about how and why this event was experienced in different ways by the affected Indigenous and non-Indigenous worlds. From economics, we show how different theories perceive and impact these different worlds, presenting some existing alternatives to the hegemonic thinking of domination and exploitation. From anthropology, we present the perspectivism concept, deriving from the field of relational ontologies, suggesting there are significant and inevitable disagreements-equivocations-among different worlds. Thus, we discuss how the social sciences can help address challenging factors that need to be considered in health approaches that intend to deal with complex global problems. In conclusion, OH should incorporate social science discussions, considering relating practice to the multiple realities in which a particular problem or conflict is inserted. Overcoming the barriers that hinder transdisciplinary dialogue is fundamental and urgent for an effective approach to the multiple and distinct interconnections among humans, animals and environments.

High SARS-CoV-2 seroprevalence in persons experiencing homelessness and shelter workers from a day-shelter in São Paulo, Brazil.

Brazil presents one of the highest COVID-19 death tolls in the world. The initial SARS-CoV-2 epicenter was São Paulo city. As of 2019, the homeless population of São Paulo city was estimated at 24,344 individuals, the largest national homeless population. The present study aimed to concomitantly assess the molecular and serological prevalence and associated risk factors of SARS-CoV-2 infection in a homeless population and related shelter workers from a day-shelter. Serum samples, nasopharyngeal and oropharyngeal swabs of persons who are homeless and shelter workers collected from August 25th to 27th, 2020 were tested for the presence of anti-SARS-CoV-2 IgM and IgG antibodies by ELISA and SARS-CoV-2 RNA by RT-qPCR, respectively. All swab samples tested negative by RT-qPCR. Seropositivity of IgM and IgG was 5/203 (2.5%) and 111/203 (54.7%) in persons who are homeless, and 5/87 (5.7%) and 41/87 (47.1%) in shelter workers, respectively, with no statistical differences between groups. The high seroprevalence found herein indicates early environmental and urban spreading of SARS-CoV-2, associated with sociodemographic and economic vulnerability.

Investigation of canine visceral leishmaniasis in a non-endemic area in Brazil and the comparison of serological and molecular diagnostic tests.

INTRODUCTION: Visceral leishmaniasis (VL) is an important zoonosis in Brazil. Previous identification of parasitized dogs can also help prevent the disease in humans, even in non-endemic areas of the country. The Brazilian Ministry of Health recommends diagnosis in dogs using a DPP® (rapid test) as a screening test and an immunoenzymatic assay (ELISA) as a confirmatory test (DPP®+ELISA), and culling infected dogs as a legal control measure. However, the accuracy of these serological tests has been questioned. METHODS: VL in dogs was investigated in a non-endemic area of the São Paulo state for three consecutive years, and the performances of different diagnostic tests were compared. RESULTS: A total of 331 dog samples were collected in 2015, 373 in 2016, and 347 in 2017. The seroprevalence by DPP®+ELISA was 3.3, 3.2, and 0.3%, respectively, and by indirect immunofluorescence assay (IFA), it was 3.0, 5.6, and 5.5%, respectively. ELISA confirmed 18.4% of DPP® positive samples. The concordance between the IFA and DPP® was 83.9%. The concordance between IFA and DPP®+ELISA was 92.9%. A molecular diagnostic test (PCR) was performed in 63.2% of the seropositive samples, all of which were negative. CONCLUSIONS: In non-endemic areas, diagnostic tests in dogs should be carefully evaluated to avoid false results.

Investigation of canine visceral leishmaniasis in a non-endemic area in Brazil and the comparison of serological and molecular diagnostic tests

Abstract INTRODUCTION: Visceral leishmaniasis (VL) is an important zoonosis in Brazil. Previous identification of parasitized dogs can also help prevent the disease in humans, even in non-endemic areas of the country. The Brazilian Ministry of Health recommends diagnosis in dogs using a DPP® (rapid test) as a screening test and an immunoenzymatic assay (ELISA) as a confirmatory test (DPP®+ELISA), and culling infected dogs as a legal control measure. However, the accuracy of these serological tests has been questioned. METHODS: VL in dogs was investigated in a non-endemic area of the São Paulo state for three consecutive years, and the performances of different diagnostic tests were compared. RESULTS: A total of 331 dog samples were collected in 2015, 373 in 2016, and 347 in 2017. The seroprevalence by DPP®+ELISA was 3.3, 3.2, and 0.3%, respectively, and by indirect immunofluorescence assay (IFA), it was 3.0, 5.6, and 5.5%, respectively. ELISA confirmed 18.4% of DPP® positive samples. The concordance between the IFA and DPP® was 83.9%. The concordance between IFA and DPP®+ELISA was 92.9%. A molecular diagnostic test (PCR) was performed in 63.2% of the seropositive samples, all of which were negative. CONCLUSIONS: In non-endemic areas, diagnostic tests in dogs should be carefully evaluated to avoid false results.

Seroprevalence and incidence of Toxoplasma gondii and Neospora caninum infection in naturally exposed domestic dogs from a rural area of São Paulo state, Brazil.

Dogs are hosts of the protozoans Toxoplasma gondii, which causes an important public health disease, and Neospora caninum. Studies that have evaluated toxoplasmosis and neosporosis for prolonged periods in dog populations are rare. We analyzed infection by both parasites in a domestic dog population over three consecutive years in São Paulo state, Brazil. In the 1st, 2nd and 3rd years of collection, 181, 193 and 172 domiciles were visited, and blood samples of 331, 371 and 348 dogs were collected for antibody serology, respectively. The seroprevalence of T. gondii in each year was 27.2%, 22.5% and 43.9%, respectively, and that of N. caninum was 7.8%, 4.8% and 6.8%, respectively. The incidence rates for T. gondii in the 2nd and 3rd collections were 13.2% and 30.0%, and those for N. caninum were 3.3% and 4.4%, respectively. Positive and negative serological conversions for both agents occurred at high frequencies during the study period. This study reveals the canine population's serological profile and demonstrates the constant exposure of dogs to the investigated pathogens, indicating the need for prevention and control measures in the region.

Demografia Médica no Brasil - 2020

A publicação Demografia Médica no Brasil 2020, com resultado da colaboração entre o Conselho Federal de Medicina (CFM) e a Universidade de São Paulo (USP), é uma produção científica que atualiza os conhecimentos acumulados na última década e traz novas informações detalhadas sobre a população de médicos e seu exercício profissional. Em 2020, o Brasil passou a contar com mais de 500 mil médicos. Esse marco vem acompanhado da persistência de desigualdades na distribuição dos profissionais, do aumento desenfreado de cursos e vagas de graduação e da ociosidade de vagas de Residência Médica. Da mesma forma, o crescimento dessa população ocorre com a exposição dos médicos ao aumento do número de vínculos e de jornadas de trabalho. Portanto, o número de médicos no país cresceu, nos últimos anos, na mesma proporção em que se impuseram novos desafios para a profissão médica e o funcionamento do sistema de saúde no país. Assim, a Demografia Médica 2020 do CFM se impõe no debate qualificado, baseado em dados e evidências, com a oferta de subsídios para a atuação das entidades e governantes comprometidos com a valorização da Medicina e as melhorias das condições de saúde da população.

Seroprevalence and incidence of Toxoplasma gondii and Neospora caninum infection in naturally exposed domestic dogs from a rural area of São Paulo state, Brazil / Soroprevalência e incidência de infecção por Toxoplasma gondii e Neospora caninum em cães domésticos naturalmente expostos em uma área rural no estado de São Paulo, Brasil

Abstract Dogs are hosts of the protozoans Toxoplasma gondii, which causes an important public health disease, and Neospora caninum. Studies that have evaluated toxoplasmosis and neosporosis for prolonged periods in dog populations are rare. We analyzed infection by both parasites in a domestic dog population over three consecutive years in São Paulo state, Brazil. In the 1st, 2nd and 3rd years of collection, 181, 193 and 172 domiciles were visited, and blood samples of 331, 371 and 348 dogs were collected for antibody serology, respectively. The seroprevalence of T. gondii in each year was 27.2%, 22.5% and 43.9%, respectively, and that of N. caninum was 7.8%, 4.8% and 6.8%, respectively. The incidence rates for T. gondii in the 2nd and 3rd collections were 13.2% and 30.0%, and those for N. caninum were 3.3% and 4.4%, respectively. Positive and negative serological conversions for both agents occurred at high frequencies during the study period. This study reveals the canine population's serological profile and demonstrates the constant exposure of dogs to the investigated pathogens, indicating the need for prevention and control measures in the region.

Resumo Os cães são hospedeiros dos protozoários Toxoplasma gondii, que causam uma importante doença para a saúde pública, e Neospora caninum. Estudos que avaliam a toxoplasmose e a neosporose por períodos prolongados em populações caninas são raros. Foi analisada a infecção por esses dois parasitas em uma população de cães domésticos e domiciliados por três anos consecutivos, no Estado de São Paulo, Brasil. Nos 1º, 2º e 3º anos de coletas, 181, 193 e 172 domicílios foram visitados, nos quais foram coletadas amostras de sangue de 331, 371 e 348 cães para sorologia, respectivamente. A soroprevalência de T. gondii em cada ano foi de 27,2%, 22,5% e 43,9%, respectivamente; e a de N. caninum foi de 7,8%, 4,8% e 6,8%, respectivamente. As taxas de incidência para T. gondii, nas 2ª e 3ª coletas, foram de 13,2% e 30,0%, respectivamente; e para N. caninum, 3,3% e 4,4%, respectivamente. As conversões sorológicas positivas e negativas para ambos os agentes ocorreram em alta frequência durante o período analisado. Este estudo revela o perfil sorológico da população canina e demonstra sua constante exposição aos patógenos investigados, o que requer medidas de prevenção e controle na região.

Socioeconomic vulnerability associated to Toxoplasma gondii exposure in southern Brazil.

Human toxoplasmosis, a protozoonosis caused by Toxoplasma gondii, has been described as a worldwide foodborne disease with important public health impact. Despite infection has reportedly varied due to differences in alimentary, cultural and hygienic habits and geographic region, social vulnerability influence on toxoplasmosis distribution remains to be fully established. Accordingly, the present study has aimed to assess T. gondii seroprevalence and factors associated to social vulnerability for infection in households of Ivaiporã, southern Brazil, with 33.6% population making half minimum wage or less, ranked 1,055th in population (31,816 habitants), 1,406th in per capita income (U$ 211.80 per month) and 1,021st in HDI (0.764) out of 5,570 Brazilian cities. Serum samples and epidemiological questionnaires were obtained from citizen volunteers with official City Secretary of Health assistance in 2015 and 2016. In overall, serosurvey has revealed 526/715 (73.57%) positive samples for anti-T. gondii antibodies by Indirect Fluorescent Antibody Test. Logistic regression has shown a significant increase associated to adults (p = 0.021) and elderly (p = 0.014) people, illiterates (p = 0.025), unemployment (p <0.001) and lack of household water tank (p = 0.039). On the other hand, sex (male or female), living area (urban or rural), yard hygiene, meat ingestion, sand or land contact, owning pets (dog, cat or both) were not significant variables of positivity for anti-T. gondii antibodies in the surveyed population. Although no significant spatial cluster was found, high intensity areas of seropositive individuals were located in the Kernel map where the suburban neighborhoods are located. In conclusion, socioeconomic vulnerability determinants may be associated to Toxoplasma gondii exposure. The increased risk due to illiteracy, adult or elderly age, unemployment and lack of household water tank were confirmed by multivariate analysis and the influence of low family income for seropositivity by the spatial analysis.

Survey of spatial distribution of vector-borne disease in neighborhood dogs in southern Brazil.

Neighborhood dogs may act as reservoirs and disseminators of vector-borne diseases in urban areas. Accordingly, the aim of this study was to ascertain the health status and the vector-borne pathogens infecting dogs living in public areas with high levels of human movement in the city of Curitiba, southern Brazil. Blood samples from 21 neighborhood dogs that were found in nine of 22 bus stations and two public parks were subjected to a complete blood cell (CBC) count, serum biochemical profiling, a commercial rapid ELISA test and a commercial real-time PCR panel of vector-borne diseases. The CBC count and serum biochemical profiling were within the normal range for dogs and only 1/21 (4.7%) of the dogs was seroreactive for Borrelia burgdorferi sensu stricto. The commercial real-time PCR panel showed that 7/21 (33.3%) of the dogs had Mycoplasma haemocanis infection, 9/21 (42.8%) had 'Candidatus Mycoplasma haematoparvum' and 4/21 (19.0%) had both. No statistical association between infected by the agents found here and abnormalities in physical examinations, laboratory tests or ectoparasite presence was found (p > 0.05). In conclusion, neighborhood dogs showed low prevalence of vector-borne diseases and satisfactory wellbeing, and dogs can be used as sentinels for disease exposure.

Serosurvey for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum in neighborhood dogs in Curitiba-Paraná, Brazil.

Neighborhood dogs may act as reservoirs for several zoonotic protozoan infections, particularly in urban areas, thus constituting a potential public health threat. Accordingly, the aim of the present study was to evaluate the exposure of neighborhood dogs to four protozoan pathogens in public areas with high levels of human movement in Curitiba, southern Brazil. Blood samples from 26 neighborhood dogs were screened by means of the indirect immunofluorescent antibody test (IFAT) for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum, and a questionnaire was answered by the respective keeper. A total of 8/26 dogs (30.7%) seroreactive to T. gondii, 3/26 (11.5%) to N. caninum and 2/26 (7.7%) to both were identified. All the samples were seronegative for T. cruzi and Leishmania spp. Pathogen seroreactivity was not associated with the daily human movements or other epidemiological variables investigated (p > 0.05). In conclusion, the low seroprevalence for T. gondii and N. caninum indicated low environmental and food risk for animal infection and the seronegativity for Leishmania spp. and T. cruzi may reflect the absence of these pathogens in urban areas of Curitiba. Moreover, neighborhood dogs may be used as environmental sentinels for the presence of protozoan pathogens and their vectors.

Serosurvey for Leishmania spp, Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum in neighborhood dogs in Curitiba-Paraná, Brazil / Inquérito sorológico para Leishmania spp, Toxoplasma gondii, Trypanosoma cruzi e Neospora caninum em cães comunitários em Curitiba-Paraná, Brasil

Abstract Neighborhood dogs may act as reservoirs for several zoonotic protozoan infections, particularly in urban areas, thus constituting a potential public health threat. Accordingly, the aim of the present study was to evaluate the exposure of neighborhood dogs to four protozoan pathogens in public areas with high levels of human movement in Curitiba, southern Brazil. Blood samples from 26 neighborhood dogs were screened by means of the indirect immunofluorescent antibody test (IFAT) for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum, and a questionnaire was answered by the respective keeper. A total of 8/26 dogs (30.7%) seroreactive to T. gondii, 3/26 (11.5%) to N. caninum and 2/26 (7.7%) to both were identified. All the samples were seronegative for T. cruzi and Leishmania spp. Pathogen seroreactivity was not associated with the daily human movements or other epidemiological variables investigated (p > 0.05). In conclusion, the low seroprevalence for T. gondii and N. caninum indicated low environmental and food risk for animal infection and the seronegativity for Leishmania spp. and T. cruzi may reflect the absence of these pathogens in urban areas of Curitiba. Moreover, neighborhood dogs may be used as environmental sentinels for the presence of protozoan pathogens and their vectors.

Resumo Cães comunitários podem atuar como reservatórios para algumas zoonoses causadas por protozoários, principalmente em áreas urbanas, constituindo potencial ameaça à saúde pública. Portanto, o objetivo do presente estudo foi avaliar a exposição de cães comunitários a quatro protozoários em áreas públicas com alta circulação de pessoas, em Curitiba, Sul do Brasil. Amostras de sangue de 26 cães comunitários foram testadas pela reação de imunofluorescência indireta (RIFI) para Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi e Neospora caninum, e um questionário foi respondido pelo respectivo mantenedor. Um total de 8/26 (30,7%) foram sororreagentes para T. gondii, 3/26 (11,5%) para N. caninum e 2/26 (7,7%) para ambos. Todas as amostras foram soronegativas para T. cruzi e Leishmania spp. Não houve associação entre sororreatividade para os patógenos pesquisados e o tráfego diário de pessoas e outras variáveis epidemiológicas analisadas (p > 0.05). Conclui-se a baixa soroprevalência para T. gondii e T. cruzi indica baixo risco ambiental e alimentar para a infecção dos animais, e a soronegatividade para Leishmania spp. e T. cruzi pode refletir a ausência desses patógenos em áreas urbanas de Curitiba. Além disso, os cães comunitários podem atuar como sentinelas ambientais quanto à presença de protozoários e seus vetores.