Dataset Information

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.

ABSTRACT: 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.

SUBMITTER: Delai RR

PROVIDER: S-EPMC8634035 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundToxocara canis and Toxocara cati are globally distributed roundworms and causative agents of human toxocariasis, via ingestion of Toxocara eggs. Control of Toxocara infections is constrained by a lack of sensitive methods for screening of animal faeces and environmental samples potentially contaminated by Toxocara eggs. In this work, a pre-analytical method for efficient extraction of DNA from Toxocara eggs in environmental samples was set up using our previously validated T. canis- and T. cati-specific quantitative real-time polymerase chain reaction (qPCR). For this purpose, the influence of different methods for egg lysis, DNA extraction and purification for removal of PCR inhibitors were assessed on environmental samples.MethodsTo select the best egg disruption method, six protocols were compared on pure T. canis egg suspensions, including enzymatic lysis and thermal or mechanical disruption. Based on the selected best method, an analytical workflow was set up to compare two DNA extraction methods (FastDNA™ SPIN Kit for Soil versus DNeasy® PowerMax® Soil Kit) with an optional dilution and/or clean-up (Agencourt® AMPure®) step. This workflow was evaluated on 10-g soil and 10-g sand samples spiked with egg suspensions of T. canis (tenfold dilutions of 104 eggs in triplicate). The capacity of the different methods, used alone or in combination, to increase the ratio of positive tests was assessed. The resulting optimal workflow for processing spiked soil samples was then tested on environmental soil samples and compared with the conventional flotation-centrifugation and microscopic examination of Toxocara eggs.ResultsThe most effective DNA extraction method for Toxocara eggs in soil samples consisted in the combination of mechanical lysis of eggs using beads, followed by DNA extraction with the DNeasy® PowerMax® Soil Kit, and completed with an additional DNA clean-up step with AMPure® beads and a sample DNA dilution (1:10). This workflow exhibited a limit of detection of 4 and 46 T. canis eggs in 10-g sand and 10-g soil samples, respectively.ConclusionsThe pre-analytical flow process developed here combined with qPCR represents an improved, potentially automatable, and cost-effective method for the surveillance of Toxocara contamination in the environment.

Project description:BackgroundToxocariasis is a worldwide helminthic zoonosis caused by infection with the larvae of the ascarid worms that comprise the Toxocara spp. Children are particularly prone to infection because they are exposed to the eggs in sandboxes and playgrounds contaminated with dog and cat feces. Certain behaviors, such as a geophagy habit, poor personal hygiene, a lack of parental supervision, close contact with young dogs, and ingestion of raw meat, as well as gender, age, and socioeconomic status, affect the prevalence of the disease. However, previous studies of the risk factors for toxocariasis have generally produced inconsistent results. An epidemiological cross-sectional study was conducted to evaluate the seroprevalence of IgG anti-Toxocara spp. antibodies and associated factors in schoolchildren from a region in the southeast of Brazil.Methodology/principal findingsA total of 252 schoolchildren aged 1 to 12 years (120 males and 132 females) were assessed. An enzyme-linked immunosorbent assay based on Toxocara canis larval excretory-secretory antigens was used to determine outcomes. A questionnaire was used to collect information on children, family, and home characteristics. Clinical and laboratory data completed the dataset investigated in this study. Seroprevalence was 15.5% (95%CI 11.5-19.8). Geophagy (aPR 2.38 [95%CI 1.36-4.18], p-value 0.029) and the habit of hand washing before meals (aPR 0.04 [95%CI 0.01-0.11], p-value ? 0.001) were factors associated with increased and decreased seroprevalence, respectively. The income factor and its related variables lost statistical significance after adjustment with a multiple Poisson regression model.Conclusions/significanceThe current study confirms that toxocariasis is a public health problem in the evaluated area; modifiable factors such as soil contact and personal hygiene appear to have a greater influence on the acquisition of infection than sociodemographic attributes, thus representing direct targets for disease prevention and control.

Project description:BACKGROUND:This report describes L. infantum infection seroprevalence in dogs in Spain through data obtained from peer-reviewed literature and a cross-sectional serological survey assessing epidemiological and habitat variables as risk factors for infection. The study also provides preliminary sand fly species distribution data and indicates factors affecting their distribution and density. METHODS:Three different studies were conducted in Spain: (i) a peer-reviewed literature seroprevalence survey (1985-2019); (ii) a cross-sectional serological survey (2011-2016); and (iii) a preliminary entomological survey (2013-2014). In the cross-sectional serological survey, 1739 dogs from 74 different locations including 25 Spanish provinces were tested for L. infantum by indirect immunofluorescence antibody test (IFAT) (antibody titre???1:100). Seroprevalence of L. infantum infection was analysed by province and bioclimatic zone. Statistics were used to analyse relationships between several dog- and environment-related variables and L. infantum seroprevalence. In parallel, during 2013-2014, sand flies were collected across the Iberian Peninsula and the Balearic Islands using CDC light traps to examine relationships between habitat-related factors and sand fly species densities (number of sand flies per trap per hour). RESULTS:The literature review revealed that the provinces showing the highest seroprevalence were Balearic Islands (57.1%), Ourense (35.6%), Málaga (34.6%) and Cáceres (34.2%), and those showing the lowest seroprevalence were Vizcaya (0%), Cantabria (2.0%) and Álava (3.3%). In our survey, anti-Leishmania IgG antibodies were detected in 176 of the 1739 dogs rendering a seroprevalence of 10.12%. Percentage seroprevalence distributions significantly varied among bioclimatic belts. Seropositivity for L. infantum was related to size (large breed dogs versus small) and were significantly higher in younger dogs (??1 years-old). In the entomological survey, 676 sand flies of five species were captured: 562 (83.13%) Phlebotomus perniciosus; 64 (9.47%) Sergentomyia minuta; 38 (5.62%) P. ariasi: 6 (0.89%) P. sergenti; and 6 (0.89%) P. papatasi. Phlebotomus perniciosus showed a greater density in the thermo-Mediterranean than in the meso-Mediterranean zone. Densities of S. minuta and P. ariasi were significantly higher in rural habitats. CONCLUSIONS:This updated seroprevalence map of L. infantum infection in dogs in Spain defines non-endemic, hypoendemic, endemic and hyperendemic areas, and confirms P. perniciosus as the most abundant sand fly vector in Spain.

Dataset Information

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.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets