Hidden in plain sight: Urban playgrounds as potential reservoirs of soil-transmitted helminths
DOI:
https://doi.org/10.63719/imrj.2026.01(SE).02Keywords:
Soil Transmitted Helminths (STH), urban playground, Polymerase Chain Reaction (PCR)Abstract
Neglected soil-transmitted helminthiases (STHs) remain an underrecognized public health concern in Malaysia, particularly in urban environments where exposure risks are often underestimated. This study assessed the prevalence and species diversity of helminth egg contamination in urban neighbourhood playgrounds in Shah Alam, Malaysia. A total of 84 soil samples and 15 faecal samples were collected and examined microscopically for helminth ova, followed by species-specific polymerase chain reaction (PCR) to identify parasites of public health significance. Helminth ova were detected in 50.0% (42/84) of soil samples, with contamination rates ranging from 47.0% to 60.0% across sampling sites. Faecal samples showed a higher positivity rate of 73.3% (11/15). Hookworms and unidentified helminth ova predominated in both sample types, with mixed infections more frequently observed in faecal samples. Among microscopy-positive soil samples, PCR detected Ascaris lumbricoides in one sample (2.4%) and Strongyloides stercoralis in one sample (2.4%), while most samples (95.2%) remained PCR-negative and were classified as unidentified species. In faecal samples, Ancylostoma duodenale was predominant (63.7%), followed by Trichuris trichiura (27.3%) and S. stercoralis (9.1%). Soil physicochemical analysis showed that most contaminated soils were acidic (85.7%, pH < 7.0) with low moisture content (61.9%, <10%), while loamy soils had the highest contamination rate (72.1%). These findings highlight urban playgrounds as potential reservoirs for STH transmission an emphasise the need for improved surveillance and targeted public health interventions in urban communities.
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