Investigating the role of environmental microorganisms , biological and chemical agents in the control of fascioliasis: A review article
Investigating the role of environmental microorganisms , biological and chemical agents in the control of fascioliasis: A review article
Shirin Khodabakhsh Arbat,1,*Arezo Karimi,2
1. Department of Parasitology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran 2. Department of Biotechnology, Shahrekord University, Shahrekord, Iran
Introduction: Fascioliasis, an important parasitic disease caused by liver fluke species of the genus Fasciola, significantly impacts both human and animal health. This disease causes considerable economic losses in the livestock industry and poses a threat to public health. The life cycle of Fasciola species is complex and involves both definitive and intermediate hosts. Adult flukes reside in the bile ducts of definitive hosts, primarily ruminants and occasionally humans. Eggs are shed in feces and develop in freshwater environments. Miracidia hatch from the eggs and infect suitable snail intermediate hosts, typically of the family Lymnaeidae. Within the snail, the parasite undergoes asexual reproduction, eventually producing cercariae that encyst on aquatic vegetation as metacercariae. Infection occurs when definitive hosts ingest these metacercariae. Over the past decade, extensive research has been conducted on controlling this parasite using environmental and chemical methods.
Methods: For this review article, a comprehensive literature search was performed across several electronic databases, including PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar. The search focused on identifying studies published between 2010 and 2024, with an emphasis on research investigating the role of environmental microorganisms, biological agents, and chemical interventions in the control of fascioliasis. Key search terms such as "Fasciola," "biological control," "environmental microorganisms," "chemical agents," and "parasite management" were used to ensure broad coverage of relevant literature. Special attention was given to studies that explored the interactions between parasites and environmental factors, with a particular focus on biological control methods.
Results: Actinomycetes are recognized as significant natural bacteria due to their wide range of biological activities. These activities include parasitism and the production of bioactive compounds such as toxins, antibiotics, and enzymes. They can synergistically affect parasites by either directly inhibiting their growth or enhancing the activity of microbial antagonists, thereby contributing to the suppression of the parasite population. A study demonstrated that Streptomyces griseolus, isolated from Egyptian soil, exhibits strong biocontrol effects against Fasciola gigantica eggs. These findings suggest that S. griseolus has high potential for use as a biological control agent against this helminth. Research indicates that probiotics such as Lactobacillus casei, enhances the innate immune system in various animal species when administered orally or intraperitoneally. This enhancement leads to improved acquired immunity.These findings suggest that the use of beneficial microorganisms could be a promising strategy for the biological control of fascioliasis. Also, in a study, it was shown that Fasciola hepatica infection in school-aged children from Peru leads to significant changes in the composition of the gut microbiota. Specifically, the study found that bacterial genera such as Lactobacillus, Bacteroides, Clostridium, and Bifidobacterium were significantly less prevalent in children infected with F. hepatica compared to those who were not infected.Researchers conducted a study to examine the activity of serine proteases in F.hepatica miracidia and the results revealed that serine protease activity in miracidia was effectively inhibited by both chemical inhibitors (such as phenylmethylsulfonyl fluoride and pepstatin) and herbal inhibitors (like soybean Bowman-Birk inhibitor). These findings suggest that the use of protease inhibitors, particularly herbal ones, may be a promising approach for controlling the life cycle of F.hepatica.
Conclusion: This review demonstrates that significant progress has been made over the past decade in using environmental microorganisms and chemical agents to control Fasciola species. The research highlights the potential of various biological control methods, including the use of Actinomycetes like Streptomyces griseolus, probiotics such as Lactobacillus casei, and the manipulation of gut microbiota. These approaches show promise in enhancing host immunity and directly inhibiting parasite growth. Additionally, the study of serine proteases in F. hepatica miracidia has opened new avenues for intervention, with both chemical and herbal inhibitors showing efficacy in disrupting the parasite's life cycle. These findings suggest that a multi-faceted approach, combining biological control methods with targeted chemical interventions, may offer the most effective strategy for managing fascioliasis. However, while these advancements are encouraging, further research is crucial to address existing challenges and develop sustainable, long-term solutions.