First Molecular Characterization of Cryptosporidium and Giardia from Pigs in Bangladesh

Cryptosporidium and Giardia are significant causes of gastrointestinal diseases in humans and animals worldwide, especially in pigs. This study investigated the molecular occurrence, genetic diversity, and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis in domestic pigs in the Chattogram Hill Tracts (CHT), Bangladesh.

A total of 408 fecal samples were collected from Rangamati, Khagrachari, and Bandarban districts and examined using nested PCR, targeting the SSU rRNA gene for Cryptosporidium and the β-giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi) genes for G. duodenalis. Nucleotide sequencing and phylogenetic analysis were conducted for molecular characterization.

The prevalence of Cryptosporidium was 3.43%, and G. duodenalis was 23.52%. The prevalence varied by several factors, although the variations were not significant for Cryptosporidium. Age, anthelmintic administration, and diarrheal status of the pigs had a significant influence on the occurrence of Giardia. Among the 14 Cryptosporidium and 96 Giardia isolates, two Cryptosporidium species (C. suis and C. scrofarum) and three G. duodenalis assemblages (A, B, and E) were found, among which assemblage A (56.25%) was the most prevalent. Additionally, 13 novel genotypic variations were identified at the bg, gdh, and tpi genes of G. duodenalis.

Pigs in the CHT region harbor Cryptosporidium and Giardia with notable genotypic diversity and zoonotic potential. Addressing this issue requires further research within a One Health framework, focusing on integrated surveillance and the development of evidence-based policies for pig farming to reduce transmission and safeguard animal and public health.