The zoonotic potential of Giardia intestinalis assemblage E in rural settings.

Giardiasis is a globally re-emerging protozoan disease with veterinary and public health implications. The current study was carried out to investigate the zoonotic potential of livestock-specific assemblage E in rural settings. For this purpose, a total of 40 microscopically positive Giardia stool samples from children with gastrointestinal complaints with or without diarrhea were enrolled in the study as well as fecal samples from 46 diarrheic cattle (18 dairy cows and 28 calves). Animal samples were examined by sedimentation method to identify Giardia spp., and then, all Giardia positive samples from human and animals were processed for molecular detection of livestock-specific assemblage E through amplification of assemblage-specific triosephosphate isomerase (tpi) gene using nested polymerase chain reaction (PCR). The results of the study revealed high unexpected occurrence of assemblage E among human samples (62.5 %), whereas the distribution among patients with diarrhea and those without was 42.1 and 81 %, respectively. On the other hand, the prevalence of Giardia spp. among diarrheic dairy cattle was (8.7 %), while only calves yielded positive results (14.3 %) and all bovine Giardia spp. were genetically classified as Giardia intestinalis assemblage E. Moreover, DNA sequencing of randomly selected one positive human sample and another bovine one revealed 100 and 99 % identity with assemblage E tpi gene sequences available at GenBank after BLAST analysis. In conclusion, the current study highlights the wide dissemination of livestock-specific assemblage E among humans in rural areas, and thus, zoonotic transmission cycle should not be discounted during the control of giardiasis in such settings.

Novel detection of Helicobacter pylori in fish: A possible public health concern.

Helicobacter pylori is one of the most common human pathogens worldwide with serious clinical outcomes. Although, H. pylori is a major water-borne pathogen, its occurrence in fish is still unknown. This leads us to conduct the current study in order to clarify this point and to investigate the potential role of fish in the epidemiology of H. pylori. For this purpose, fecal samples were obtained from 315 fish from different species and were caught from various aquatic environments at different localities in Egypt. The obtained fecal samples were examined for the occurrence of H. pylori using monoclonal antibody based lateral flow immunoassay for antigen detection and after then the positive samples were confirmed by PCR. In addition, fecal samples from 18 fish handlers were also examined for the presence of H. pylori by lateral flow technique. The overall prevalence rates of H. pylori in the examined fish were 6.7% and 1.9% for LF and PCR, respectively, whereas 61.1% of fish handlers were positive. Only tilapia fish showed positive results by both techniques in rates 10.9% and 3.1%, respectively. Interestingly, H. pylori was detected in cultured and wild tilapia in various aquatic environments at different localities, whereas all other fish species were negative even those that were collected from the same water source where positive tilapia were caught. These results concluded that tilapia fish may be considered as a potential zoonotic reservoir for H. pylori and thus, H. pylori may become a new fish-borne pathogen. Further studies are needed to investigate the occurrence of H. pylori in other fish species.

Fish as a possible reservoir for zoonotic Giardia duodenalis assemblages.

Giardiasis is a re-emerging infectious disease of worldwide significance caused by Giardia duodenalis. This study investigated the occurrence of zoonotic G. duodenalis assemblages in fish to explore the possible role of fish in the epidemiology of human giardiasis. For this purpose, 92 fish (Tilapia nilotica and Mugil cephalus) collected from (fish farms and Nile River) at different governorates in Egypt were examined for the presence of G. duodenalis in their feces by using enzyme linked immunosorbent assay, then positive fecal samples were tested by duplex PCR for identification of triose phosphate isomerase (tpi) gene specific for zoonotic assemblages A and B. The overall prevalence of G. duodenalis in the examined fish was 3.3%, while the detection rates among the examined fish species were 2.9% and 4.2% for T. nilotica and M. cephalus, respectively. G. duodenalis was detected in the feces of both farmed and wild fish whereas all isolates were genotyped as assemblage A. In conclusion, the occurrence of zoonotic G. duodenalis assemblage A in the examined fish species at two different aquatic environments underlines the possibility of fish to be an additional reservoir for zoonotic G. duodenalis assemblages that contributes in the contamination of water with this pathogen and thus the role of fish in the epidemiology of human giardiasis cannot be ruled out.