Trichuris spp. in Animals, with Specific Reference to Neo-Tropical Rodents

Effect of Soil Temperature on Canine Soil-Transmitted Nematodes in Kandy District with the First Record of Hookworm, Ancylostoma tubaeforme from Sri Lanka

PURPOSE

Soil-transmitted nematodes (STNs) are widespread in tropical and subtropical regions, particularly where the communities are socio-economically challenged. We investigated the effect of soil temperature on the prevalence and intensity of STN infection in free-roaming dogs.

METHODS

Fresh faecal samples collected from free-roaming dogs in Digana and Pussellawa town areas in the Kandy District, Sri Lanka, were microscopically analysed for canine STNs. Soil temperature was measured at each sampling site. Highly prevalent canine hookworm Ancylostoma, was further studied using PCR and sequencing, followed by phylogenetic analysis.

RESULTS

The soil temperature ranged between 28 and 31 °C (mean = 29.79 °C) and 18-21 °C (mean = 19.52 °C) in Digana and Pussellawa, respectively, showing a significant difference in the two sites (Students t-test t = 1.68, p < 0.0001). Of the total 44 dogs sampled, 41 (93.2%) were positive for STNs. During microscopic analysis, five nematodes: Ancylostoma spp., Capillaria sp., Strongyloides sp., Toxocara canis, and Trichuris sp., were identified. Ancylostoma species (93.2%) were the most prevalent, followed by Strongyloides sp. (22.7%) and Toxocara canis (15.9%). Infection prevalence of Strongyloides sp. was higher in Digana (40.9%) compared to that in Pussellawa (4.5%; Chi-square test, χ2 = 8.28, p = 0.004) and also the infection intensity from Digana (EPG = 8.02 ± 20.2) compared to that from Pussellawa (0.45 ± 2.1; Mann Whitney U test, p = 0.006). Amplicons (ITS1-5.8S-ITS2) of the expected size for A. caninum, and A. tubaeforme were produced. An A. caninum sequence reported here (OQ101719) illustrated the highest similarity of 99.2% to one of the local sequences (MZ707153) upon pairwise comparison.

CONCLUSION

Digana, with a higher soil temperature than Pussellawa, had a significantly higher prevalence and infection intensity, particularly Strongyloides sp. This study also signifies the first molecular identification of hookworm species A. tubaeforme in Sri Lanka.

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

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.

Prevalences and Characteristics of Trichuris Spp. Infection in Sheep in Pastoral Areas of the Tianshan, Xinjiang, China

Introduction

Nematodes of the Trichuris genus are commonly reported parasites that can cause trichuriasis in many animals, which leads to inflammation, intestinal bleeding and reductions of productivity in livestock. Knowledge of the prevalence of Trichuris infestation in the Tianshan ovine population and of the nematode species parasitising the population is not exhaustive, and this study aimed to expand the knowledge.

Material and Methods

A total of 1,216 sheep slaughtered in five pasture areas in the Tianshan Mountains of Xinjiang were investigated and a phylogenetic analysis based on the mitochondrial cox1 gene was performed to clarify the genetic relationships of the various Trichuris species.

Results

Sheep totalling 1,047 were infected with Trichuris spp. establishing the rate at 86.1%. Using a morphological protocol, six documented and one undefined species were identified, namely T. gazellae, T. lani, T. ovina, T. longispiculus, T. concolor, T. discolor and Trichuris sp. Among them, T. gazellae and T. lani were the dominant species, accounting for 34.5% and 31.0% of Trichuris spp., respectively. Phylogenetic analysis divided the detected species of Trichuris spp. into two genetic clades (clade I and clade II). The six documented species that can infect sheep and the undefined species were clustered into clade I, with inter- and intra-species genetic diversity apparent.

Conclusion

This survey described in detail the morphological characteristics of six known and one undefined species of Trichuris, which not only enriched the taxonomic information on record regarding Trichuris spp., but also provided valuable epidemiological data for the prevention and control of trichuriasis in sheep.