Temporal and spatial patterns of Trichuris trichiura eggs: a potential threat to human health in Pakistan

Abstract

Summary This study investigates the presence of Trichuris trichiura eggs in soil samples collected from urban areas in Lahore, Pakistan. A total of 3600 soil samples were collected over two years from Lahore’s urban regions. The detection of helminth eggs in these samples was performed using sodium hypochlorite (NaOCl) as a diagnostic technique. The study reveals an overall prevalence rate of T. trichiura at 0.97 % (35 out of 3600) in the contaminated soil samples from Lahore’s slum areas. When analyzing the data by geographical areas, the study found the highest prevalence of T. trichiura in Allama Iqbal Town (1.83 %, 11 out of 600), followed by Samanabad (1.16 %, 7 out of 600), Wapda Town (1.00 %, 6 out of 600), Gulberg (1.00 %, 6 out of 600), and Cantt (0.50 %, 3 out of 600). Conversely, Valencia Town had the lowest prevalence rate at 0.33 % (2 out of 600). However, these variations in prevalence rates were not statistically significant (p = 0.117). Prevalence rates of T. trichiura’s eggs varied significantly across different sampling seasons (p>0.001). In autumn, a total of 900 soil samples were collected, with 19 samples (2.11 %) testing positive for T. trichiura. This rate was notably higher compared to the prevalence rates observed in winter, spring, and summer, which were 0.66 %, 0.22 %, and 0.88 %, respectively. Regarding the sampling months, the study observed a significantly higher prevalence during September (3.33 %, 10 out of 300), followed by October (2.33 %, 7 out of 300), and August (1.33 %, 4 out of 300). Prevalence rates gradually decreased in other months, ranging from 1 % to 0.33 % (3 to 1 out of 300), with no parasite detection in March (0 %, 0 out of 300) (p < 0.001). This research underscores soil contamination due to fecal waste and highlights public unawareness of parasite biology, driven by open defecation practices.