Mini Review - Journal of Parasitic Diseases: Diagnosis and Therapy (2025) Volume 10, Issue 2

Zoonotic Parasites: A Cross-Species Public Health Challenge

Elizabeth Opiyo^*

Drugs for Neglected Diseases initiative (DNDi), Switzerland

Corresponding Author:

Elizabeth Opiyo
Kenya Medical Research Institute (KEMRI), University of Nairobi. Kenya
E-mail:eopiyo@kemri.org

Received: 02-Apr-2024, Manuscript No. AAPDDT-25-166443; Editor assigned: 03-Apr-2024, AAPDDT-25-166443(PQ); Reviewed: 01-Apr-2024, QC No. AAPDDT-25-166443; Revised: 14-Apr-2024, Manuscript No. AAPDDT-25-166443 (R); Published: 22-Apr-2024, DOI:10.35841/2591-7846.10.2.220

Citation: Opiyo E. Zoonotic Parasites: A Cross-Species Public Health Challenge, J Parasit Dis Diagn Ther. 2025; 10(2):220

Introduction

Host-parasite interaction refers to the dynamic and often complex biological relationship between a host organism and a parasitic entity that lives on or inside it, usually at the host’s expense. This interaction is central to parasitology and has implications for disease progression, immune system modulation, and evolutionary biology. Understanding these interactions is critical for developing targeted strategies in the management, prevention, and treatment of parasitic infections [1, 2, 3, 4].

Nature of Host-Parasite Interaction Parasites have evolved various strategies to exploit their hosts, while hosts, in turn, have developed defense mechanisms to resist or tolerate infections. This co-evolution results in a spectrum of interactions, ranging from acute pathogenicity to chronic, asymptomatic infections. The interaction can be classified as: Obligate or facultative: Some parasites require a host to complete their life cycle (obligate), while others may survive independently (facultative). Endoparasitic or ectoparasitic: Endoparasites live inside the host (e.g., Plasmodium, Leishmania), while ectoparasites reside on the body surface (e.g., ticks, lice) [5, 6, 7].

Immune Responses in Hosts The host’s immune system is the first line of defense against parasitic invasion. Upon detection of the parasite, the immune response may include: Innate immunity: Macrophages, neutrophils, dendritic cells, and natural killer (NK) cells recognize and attack the invader using pattern recognition receptors (PRRs). Adaptive immunity: Involves activation of B and T lymphocytes, leading to the production of parasite-specific antibodies and cell-mediated responses. However, many parasites have evolved mechanisms to evade or suppress host immunity, such as antigenic variation (e.g., Trypanosoma brucei), immunosuppression (e.g., Toxoplasma gondii), and modulation of cytokine signaling pathways [8, 9, 10].

Co-evolution and Adaptation Host-parasite relationships often reflect a long history of coevolution. This arms race leads to a balance where highly virulent parasites may diminish over time to ensure host survival and continued transmission. Some parasites and hosts reach a state of equilibrium, resulting in chronic but non-lethal infections. Clinical and Epidemiological Implications Understanding host-parasite interactions is crucial for: Vaccine development: Identifying antigens involved in immune evasion can aid vaccine design. Drug targeting: Disrupting key pathways in parasite survival mechanisms. Epidemiology: Identifying host and environmental factors helps in controlling transmission.

Conclusion

Host-parasite interaction is a finely tuned biological process involving reciprocal adaptations. Advances in molecular biology, immunology, and genomics have greatly enhanced our understanding of these interactions, offering new opportunities for diagnostics, therapeutics, and preventive strategies. Continued research in this area is essential for addressing the global burden of parasitic diseases and for anticipating how emerging parasites may adapt in response to changes in hosts and environments.

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