Molecular Detection of Taenia taeniaeformis in Wild Rats and Its Definitive Hosts from Pulau Pinang, Malaysia
Abstract
Taenia taeniaeformis is a zoonotic tapeworm affecting cats and dogs as definitive hosts, rodents as intermediate hosts, and occasionally humans as accidental hosts. Infected animals may suffer from weight loss, vomiting, malnutrition, and intestinal obstruction, while their presence in urban settings raises public health concerns. This study aims to determine the occurrence and identification of T. taeniaeformis in wild rats, domestic cats, and dogs in several selected locations in Pulau Pinang, Malaysia. From October 2022 to March 2023, 146 wild rats were trapped on both the mainland and the island of Pulau Pinang, and faecal samples from cats and dogs were collected from public spaces, veterinary clinics, and shelters. A total of 162 faecal samples (107 cats, 55 dogs) were examined using Sheather’s sugar flotation method. Only one cat (0.9%) tested positive for cyclophyllidean eggs, while none were detected in dogs. For molecular confirmation, 44 randomly selected samples (30 cats, 14 dogs) were examined, which yielded 20 (10 cats, 10 dogs) clear PCR bands, which were subjected to sequencing. Additionally, one cat faecal sample from Cat Beach Sanctuary that was examined positive for cyclophyllidean eggs was also sequenced. However, the resulting sequence did not match T. taeniaeformis sequences in the NCBI database. Based on morphological characterization, all the recovered larvae showed features consistent with T. taeniaeformis. Thus, three randomly selected larval isolates obtained from rats underwent molecular analysis. It was found that one sample (OR790451) yielded a clear PCR band, which showed high similarity with registered T. taeniaeformis sequences. Phylogenetic analysis of 12S rDNA revealed that this isolate clustered closely with a Chinese isolate from the leopard cat (Prionailurus bengalensis, ON055368), confirming its identity. The findings highlight wild rats as important reservoirs and emphasize the need for continued surveillance in companion animals.