Dog and Cat Contact as Risk Factor for Human Toxocariasis: Systematic Review and Meta-Analysis

Abstract

Toxocariasis, a neglected parasitic zoonosis with worldwide distribution, has been reportedly associated to different risk factors in several epidemiological and meta-analysis studies. However, dog and cat contact (environmental and animal exposure) as isolated associated risk factor for children and adults remains to be fully established. Accordingly, the present meta-analysis has aimed to directly assess dog and cat contact for toxocariasis seropositivity in under-18 and adult persons, using a survey strategy of PubMed/Medline, Embase, Scopus and Scielo Databases, from January 2009 to December 2021. A meta-analysis model of random effects was applied to estimate odds ratio (OR) with 95% Confidence Interval (CI). The statistical heterogeneity was evaluated by the Cochran Q-Test and I2 values. A total of 41 transversal studies (n = 20.515 individuals) from different geographic regions (classified by the World Health Organization) were included herein. In overall, 1,882/13,496 (13.95%; 95% IC = 13.4–14.5) youngers and 513/7.019 (7.3%; 95% CI = 6.7–7.9) adults in contact with dogs or cats were serologically reagent for anti-Toxocara antibodies. Association of dog and cat contact was observed only in youngers, with both dogs (OR = 1.53; p < 0.0001) and cats (OR = 1.64; p = 0.0001). In addition, association of dog and contact and serology was statistically significant in populations of Americas (OR = 1.37; 95% CI = 1.1–1.7), Middle East (OR = 2.9; 95% CI = 1.6–5.1) and West Pacific (OR = 1.6; 95% IC = 1.3–1.9). In conclusion, contact with dogs and cats, particularly by younger individuals and in regions such as Americas, Middle East, and West Pacific, should be always a public health concern for toxocariasis. Moreover, dogs and cats should be periodically dewormed, washed and hair cleaned prior to contact with youngers. Finally, robust statistical results herein may serve as basis for future strategies and preventive measures for safer dog and cat contact.

Seroprevalence of human toxocariasis in Latin America and the Caribbean: a systematic review and meta-analysis

“…Our findings showed that the seroprevalence was higher in patients who had a dog in the household. This is consistent with the results of a systematic review in the Americas, Middle East, and Western Pacific Region, which found a statistically significant association between seropositivity for Toxocara and contact with pets, although only in younger people with both dogs and cats ( 132 ). Toxocariasis has a fecal–oral route of transmission where domestic dogs accounted for 39% of the total egg production, followed by feral cats, domestic cats, and foxes ( 4 ).…”

Who Let the Dogs Out? Unmasking the Neglected: A Semi-Systematic Review on the Enduring Impact of Toxocariasis, a Prevalent Zoonotic Infection

“…However, this way of transmission may be underestimated since transmission of Toxocara to humans via food consumption has not been the subject of extensive research [53] and should be further carefully evaluated. Moreover, despite the small number of embryonated eggs that can be found on the host hair of well-cared animals, human contact with contaminated hair of dogs or cats may represent a further way for transmission [60][61][62][63].…”

One health approach to toxocariasis in quilombola communities of southern Brazil

“…Additionally, dogs and cats were mostly unleashed, free-roaming, and not dewormed in the studied quilombola communities. As contact with dogs and cats has already been considered another associated risk factor for toxocariasis, mainly in younger people [ 11 , 56 ], companion animal deworming should be always recommended to reduce Toxocara spp. egg shedding into the environment and posterior transmission via soil ingestion to the exposed population [ 57 ].…”