One Health Approach in Serosurvey of Toxoplasma gondii in Former Black Slave (Quilombola) Communities in Southern Brazil and Among Their Dogs

Abstract

Brazilian quilombos are rural semi-isolated remnant communities of former black slaves and their descendants who traditionally maintained themselves through archaic subsistence livestock and agriculture practices and historically lacked specific public health policies. Although such individuals and their dogs may be exposed to zoonotic pathogens such as Toxoplasma gondii, no study to date has assessed these human-animal populations together. Populations in four different Brazilian quilombos in southern Brazil were evaluated. Overall, 93/208 people (44.7%) and 63/100 dogs (63.0%) were seropositive for IgG anti-T. gondii antibodies by indirect immunofluorescent antibody test (IFAT), 4/208 (1.9%) human samples seropositive for IgM anti-T. gondii antibodies, with a human-dog seropositivity ratio for IgG of 0.71. Quilombola individuals ingesting game meat were 2.43-fold more likely (95% CI: 1.05–5.9) to be seropositive. No risk factors were associated with seropositivity among dogs, thus suggesting that their exposure to T. gondii was random. Surprisingly, our research group had previously found an inverted human-dog ratio for T. gondii seropositivity of 2.54 in the urban area of a nearby major city. Because consumption of raw/undercooked game meat by quilombola individuals may have contributed to higher exposure, higher overall seroprevalence among dogs may have also indicated interaction with wildlife. Although these dogs may hunt wildlife without their owners’ awareness, the higher dog seropositivity may also be related to feeding from discarded food in the community or backyard livestock animals and drinking surface water contaminated with oocysts. Thus, wildlife cannot be singled out as the reason, and future studies should consider sampling water, soil, wildlife, and livestock tissues, to fully establish the source of infection in dogs herein.

One health approach to toxocariasis in quilombola communities of southern Brazil

“…In Brazil, serosurveys and a review study [ 62 ] have indicated no association between consumption of raw meat and toxocariasis [ 13 , 53 , 63 ]. As previously shown for quilombola communities, although having low consumption of raw and undercooked meat, the logistic regression showed that those individuals who said they consumed raw or undercooked game meat were 2.4-fold more likely ( P = 0.042, 95% CI = 1.1–5.9) to be seropositive for Toxoplasma gondii [ 64 ].…”

One Health approach for Brucella canis: Serological and molecular detection in animal-hoarding individuals and their dogs

“…Furthermore, despite the absence of seropositivity in individuals with AHD and the comparatively low seroprevalence in dogs in the present study, B. PLOS NEGLECTED TROPICAL DISEASES canis outbreaks should be considered in such human populations due to the high burden and recurrent character of B. canis circulation in high-density dog populations and the constant introduction of susceptible animals. These findings in dogs highlight human vulnerability as a risk factor for brucellosis, as has been observed for other zoonotic diseases in homeless, indigenous, and quilombola communities [45][46][47][48]. In addition, negative results for individuals with AHD may indicate that B. canis has the lowest zoonotic potential in the genus Brucella [12,17].…”

Serosurvey of Coxiella burnetii in Descendants of Former Black Slaves (Quilombola Communities) of Southern Brazil

“…A total of 83/153 (54.2%) cases were reported in slaughterhouse workers in Medellín, Colombia [ 27 ], 13/54 (24.1%) in veterinary professionals and students in Quito, Ecuador [ 28 ], and 1/99 (1.0%) in the healthy population of Buenos Aires, Argentina [ 29 ]. The study of vulnerable populations has brought a different perspective on how zoonotic diseases affect populations, alerting them to new associated risk factors and demanding a One Health approach to human, animal, and environmental health [ 30 ]. In the Brazilian Amazon, an indigenous population was investigated, which resulted in no (0/73) seropositive individuals [ 31 ].…”