Impact of helminth infections on clinical and epidemiological features of microbial infections, and vaccine responses in ruminants: a systematic review.

Impact of helminth infections on clinical and epidemiological features of microbial infections, and vaccine responses in ruminants: a systematic review. Abstract Helminth infections are ubiquitous in animal populations, and their interactions with concurrent or subsequent microbial infections can alter clinical and epidemiological features of infectious diseases and outcomes of vaccines. We used the PRISMA 2009 guidelines to conduct a systematic review of helminth-microbial-pathogen interactions and their impact on epidemiology and clinical outcomes of microbial infections in ruminants. Of the 1,375 probable studies identified through Google Scholar and PubMed databases, 20 studies met our inclusion criteria and were qualitatively analysed. Fourteen studies were on domestic ruminants, while six were on African buffaloes. Individual helminths investigated were Fasciola hepatica (six studies) Haemonchus contortus (three studies), Ostertagia ostertagi (one study) and Dicrocoelium dendriticum (one study), while the rest looked at gastrointestinal nematodes in general. Thirteen studies evaluated interactions between helminths and bovine tuberculosis (BTB), trypanosomes and theileria pathogens while four focused on responses to vaccination against rabies, bovine respiratory pathogens and Bacillus of Calmette-Guérin. Helminths interacted with Trypanosoma spp, Mycobacterium bovis, Theileria parva synergistically to aggravate clinical anaemia as measured by PCV and mortality. Furthermore, concurrent helminth infections were reported to lower the sensitivity of BTB diagnostic tests, but they did not appear to affect antibody responses to vaccines. We envision that helminths may interact with microbial pathogens in a number of ways, but primarily through immune pathways to modify clinical and epidemiological features of infections in ruminants. The implications of these interactions include missed diagnosis, underestimation of disease burden and increased severity of disease outcomes. Formats available You can view the full content in the following formats: Indexing Terms Descriptors - animal parasitic nematodes - bacterial diseases - BCG vaccine - clinical aspects - concurrent infections - disease prevention - East Coast fever - epidemiology - fascioliasis - health protection - helminthoses - helminths - immune response - immunization - liver flukes - mortality - mycobacterial diseases - ostertagiosis - protozoal infections - systematic reviews - theileriosis - trematode infections - trypanosomiasis - tuberculosis - vaccination - vaccines - parasites - infections - parasitoses - immune sensitization Identifiers - animal-parasitic nematodes - nematode parasites of animals - nematodes of animals - bacterial infections - bacterioses - bacterium - clinical picture - fluke infections - parasitic worms - immunity reactions - immunological reactions - death rate - mycobacterial infections - protozoal diseases - trypanosomosis - parasitosis - parasitic diseases - parasitic infestations Organism Descriptors Broader Terms - Bubalus - Bovidae - ruminants - Artiodactyla - mammals - vertebrates - Chordata - animals - eukaryotes - Dicrocoelium - Dicrocoeliidae - Digenea (Trematoda) - Trematoda - Platyhelminthes - invertebrates - Fasciola - Fasciolidae - Haemonchus - Haemonchidae - Rhabditida - Chromadoria - Chromadorea - Nematoda - Mycobacterium - Mycobacteriaceae - Corynebacterineae - Actinomycetales - Actinobacteridae - Actinobacteria - Bacteria - prokaryotes - Ostertagia - Theileria - Theileriidae - Piroplasmorida - Apicomplexa - Protozoa - Trypanosomatidae - Kinetoplastida - Sarcomastigophora Information & Authors Information Published In 2024 Copyright Open Access This preprint is distributed under the terms of the Creative Commons CC0 Public Domain Dedication waiver (https://creativecommons.org/publicdomain/zero/1.0/), which permits unrestricted use, distribution, and reproduction in any medium, without asking permission. History Issue publication date: 2024 Submitted: 10 January 2024 Published online: 10 January 2024 Language English Authors Metrics & Citations Metrics SCITE_ Citations Export citation Select the format you want to export the citations of this publication. EXPORT CITATIONSExport Citation View Options View options Login Options Check if you access through your login credentials or your institution to get full access on this article.