Unveiling the Enduring Challenge of Toxocariasis on Reunion Island: A 2021 Serological Snapshot
Table of Contents
Introduction: A Persistent Parasitic Concern
Reunion Island, a French overseas territory nestled in the Indian Ocean, presents a unique epidemiological landscape. Characterized by a young population and a notable level of socio-economic precariousness, this tropical island, spanning 2512 km², faces ongoing health challenges. Among these, toxocariasis, a parasitic infection caused by the roundworm Toxocara canis (commonly found in dogs), has been a long-standing concern.
A pivotal study conducted between 1987 and 1989 revealed a striking 93% seroprevalence of T. canis in the Reunion Island population, a figure confirmed by Western Blot analysis. This early research, which examined 387 samples collected for cysticercosis surveillance, also identified a significant correlation between infection and factors such as age and limited access to safe drinking water. the high seroprevalence reported then made it challenging for local physicians to differentiate clinical presentations,and crucially,data on T. canis seroprevalence has not been updated since.
Adding to this complex picture, Reunion Island grapples with a significant population of stray dogs, largely comprising abandoned pets.Estimates from 2018 placed this number at around 42,000.In response to the burden of zoonotic diseases,including toxocariasis,health authorities have implemented various measures in recent decades. These initiatives have focused on reducing the stray dog population and improving sanitary conditions across the island.
Given the ancient high seroprevalence and the ongoing efforts to mitigate zoonotic risks, understanding the current serological status of toxocariasis is paramount. This study aims to shed light on the characteristics of individuals suspected of toxocariasis who underwent T. canis serology at the local university hospital in 2021, providing a much-needed update on this persistent public health issue.
The Island Context: Environment and Demographics
Reunion Island’s tropical climate and its geographical location, approximately 700 km east of Madagascar, contribute to its unique ecological and epidemiological profile. The island’s relatively young population, coupled with a notable degree of precariousness, creates a demographic context that can influence the prevalence and impact of infectious diseases.
Stray Dog Population: A Key Reservoir
The significant number of stray dogs on Reunion Island, estimated at 42,000 in 2018, represents a critical factor in the transmission cycle of T. canis.These animals, frequently enough abandoned pets, serve as a primary reservoir for the parasite. The presence of a large, mobile population of infected dogs increases the likelihood of environmental contamination with Toxocara eggs, which are shed in their feces. These eggs are highly resilient in the environment and can remain infective for extended periods,posing a continuous risk of exposure to humans,especially through contaminated soil,water,or food.
Public health Interventions: addressing Zoonotic threats
Recognizing the threat posed by zoonotic diseases, Reunion Island has seen the implementation of various public health measures over the past few decades. These interventions have primarily targeted the reduction of the stray dog population through initiatives such as animal control programs, sterilization campaigns, and public awareness initiatives aimed at responsible pet ownership. Concurrently,efforts to improve general sanitary conditions,including access to clean water and proper waste management,are crucial in breaking the transmission routes of parasites like T. canis. The effectiveness of these ongoing efforts in potentially altering the seroprevalence of toxocariasis is a key area of interest.
Study Objective: Illuminating current Seroprevalence
The primary objective of this study was to provide an updated understanding of T. canis seroprevalence on Reunion Island by examining the characteristics of patients who were suspected of having toxocariasis and underwent serological testing at the local university hospital in 2021. By analyzing the demographic and clinical profiles of these individuals, we aim to:
* Assess the current serological status: Determine the proportion of individuals presenting with suspected toxocari
