Occurrence of Eucoleus aerophilus in wild and domestic animals: a systematic review and meta-analysis

Prevalence and genetic diversity of the lung nematode Eucoleus aerophilus in red foxes (Vulpes vulpes) in Central Europe (Poland) assessed by PCR and flotation

Eucoleus aerophilus is the causative agent of respiratory capillariosis in wild and domestic carnivores and has sporadically affected humans. To date, this parasite has been detected in 38 countries, confirming its worldwide distribution. The aim of this study was to evaluate the prevalence of E. aerophilus in red fox populations from Central Europe and to describe the sequence variations in the partial cox1 gene of this parasite recovered from stool samples. An investigation was carried out using 342 samples of red foxes faeces investigated via seminested PCR and coproscopy. PCR results confirmed the presence of E. aerophilus DNA in 230 samples and E. boehmi DNA in 14 samples. Molecular analysis of the retrieved sequences revealed 22 haplotypes of E. aerophilus, EaPL1-EaPL22, and 4 haplotypes of E. boehmi, EbPL1-EbPL4. Coproscopic examination revealed that eggs of the Capillariidae family were most prevalent in all regions, with a mean prevalence of 73%. Furthermore, the following eggs were detected: Taeniidae (21.3%), Toxocara spp. (26.3%), Toxascaris leonina (5.3%), Trichuris vulpis (1.5%), trematodes (23.4%), hookworms (2.3%) and Mesocestoides spp. (1.8%). This study evaluated the prevalence of E. aerophilus in red fox populations in selected regions of Poland. To the best of our knowledge, this is the first molecular study on E. aerophilus in Poland.

Low intestinal parasite prevalence in Finnish pet dogs and cats

BACKGROUND

This study updates the knowledge of current canine and feline endoparasitic prevalence in Finland. The previous studies reported intestinal worm prevalence of 5.9% in dogs and 7.1% in cats. We also determined the anthelmintic regime and background data of dogs and cats concerning Toxocara spp.

INFECTION

Altogether 664 canine and 379 feline (including 46 shelter cats') fecal samples from over six-month-old animals were examined with quantitative Mini-FLOTAC method using zinc sulfate with a specific gravity of 1.35. Of these samples, 396 canine and 89 feline samples were analyzed using the Baermann method for nematode larvae. A fenbendazole efficacy study was conducted with 12 animals positive for Toxocara spp.

RESULTS

Endoparasites were found in the feces of 3.5% of dogs, 3.6% of pet cats, and 41.3% of shelter cats. The most common findings in dogs were strongylid (1.7%) and Toxocara canis (0.9%) eggs. Trematode (0.4%), Eucoleus spp. (0.3%), taeniid (0.2%), and Trichuris vulpis (0.2%) eggs, and Cystoisospora spp. oocysts (0.2%) were also detected. One dog (0.2%) was positive for Crenosoma vulpis based on the Baermann method. Toxocara cati (3.3%), taeniid (0.6%), and trematode (0.3%) eggs were found in pet cats' samples. The findings in shelter cat samples were T. cati (34.8%), Eucoleus spp. (13.0%), Cystoisospora spp. oocysts (10.9%), taeniids (8.7%), and Toxoplasma gondii/Hammondia hammondii oocysts (2.2%). Fenbendazole efficacy was adequate in all treated animals, except one cat. The background data revealed 31.2% of dogs being dewormed less than once a year or never. Under twelve-month-old dogs and dogs that were dewormed twice a year were most likely to be T. canis- infected. Shelter cats, male cats, mixed-breed cats, cats that were dewormed two to four times a year, and cats with a history of parasitic infections were most likely to be T. cati infected.

CONCLUSIONS

The prevalence of pet canine and feline intestinal parasites in Finland is low, particularly the Toxocara spp.

PREVALENCE

In free-roaming cats Eucoleus spp. is surprisingly prevalent. The parasite control strategies reported do not follow the ESCCAP guidelines. Typically, owners deworm their pets only once a year or less frequently.

Human parasitic infections of the class Adenophorea: global epidemiology, pathogenesis, prevention and control

BACKGROUND

Human parasitic infections caused by Adenophorean nematodes encompass a range of diseases, including dioctophymiasis, trichuriasis, capillariasis, trichinellosis, and myositis. These infection can result in adverse impacts on human health and cause societal and economic concerns in tropical and subtropical regions.

METHODS

This review conducted searches in PubMed, Embase and Google Scholar for relevant studies that published in established databases up to April 26, 2024. Studies that focused on the common morphology, life cycle, disease distribution, clinical manifestations, and prevention and control strategies for Adenophorean parasitic diseases in humans were included.

RESULTS

Adenophorean nematodes exhibit shared morphological characteristics with a four-layered cuticle; uninucleate epidermal cells; pseudocoelom with six or more coelomocytes; generally three caudal glands; five esophageal glands; two testes in males with median-ventral supplementary glands in a single row; tail in males rarely possessing caudal alae; amphids always postlabial; presence of cephalic sensory organs; absence of phasmids; and a secretory-excretory system consisting of a single ventral gland cell, usually with a non-cuticularized terminal duct. Humans play two important roles in the life cycle of the nematode class, Adenophorea: 1) as a definitive host infected by ingesting undercooked paratenic hosts, embryonated eggs, infective larvae in fish tissue and meat contaminated with encysted or non-encysted larvae, and 2) as an accidental host infected by ingesting parasitic eggs in undercooked meat. Many organs are targeted by the Adenophorean nematode in humans such as the intestines, lungs, liver, kidneys, lymphatic circulation and blood vessels, resulting in gastrointestinal problems, excessive immunological responses, cell disruption, and even death. Most of these infections have significant incidence rates in the developing countries of Africa, Asia and Latin America; however, some parasitic diseases have restricted dissemination in outbreaks. To prevent these diseases, interventions together with education, sanitation, hygiene and animal control measures have been introduced in order to reduce and control parasite populations.

CONCLUSIONS

The common morphology, life cycle, global epidemiology and pathology of human Adenophorean nematode-borne parasitic diseases were highlighted, as well as their prevention and control. The findings of this review will contribute to improvement of monitoring and predicting human-parasitic infections, understanding the relationship between animals, humans and parasites, and preventing and controlling parasitic diseases.

Efficacy of a topical formulation containing eprinomectin, esafoxolaner and praziquantel (NexGard® Combo) in the treatment of natural respiratory capillariosis of cats

Feline pulmonary capillariosis is a significant disorder due to its distribution and clinical impact. This study evaluated the safety and efficacy of two administrations 28 days apart of a topical solution containing esafoxolaner, eprinomectin and praziquantel (NexGard® Combo) in treating Eucoleus aerophilus (syn. Capillaria aerophila) infection in naturally infected cats. Cats were allocated to two groups: G1 cats (n = 23) received two treatments at study days (SDs) 0 and 28 (±2) and were evaluated for 6 weeks, and G2 cats (n = 17) served as a negative control for 6 weeks and were then treated twice on SDs 42 (±2) and 70 (±2), allowing for an additional 6-week assessment of efficacy. Each cat was subjected to McMaster coproscopy at SDs -7/0, 28 (±2) and 42 (±2) for both groups, 70 (±2) and 84 (±2) only for G2. Clinical examination and chest radiographic images were performed at SDs 0, 28 (±2) and 42 (±2) for G1 and G2, 70 (±2) and 84 (±2) only for G2. The comparison of EPG (eggs per gram of feces), clinical (CS), and radiographic scores (RS) at each time-point was used as a criterion. The efficacy based on the EPG reduction was 99.5% (G1) and 100% (G2) after two administrations of NexGard® Combo 2 weeks apart. At SD 0, no significant differences for CS and RS were recorded between G1 and G2, while a significant reduction (p < 0.05) was observed post-treatment for CS, RS, oculo-nasal discharge, auscultation noises, and cough. Two doses of NexGard® Combo 28 days apart stopped egg shedding and significantly improved clinical alterations in cats infected by E. aerophilus.

Bacterial contact induces polar plug disintegration to mediate whipworm egg hatching

The bacterial microbiota promotes the life cycle of the intestine-dwelling whipworm Trichuris by mediating hatching of parasite eggs ingested by the mammalian host. Despite the enormous disease burden associated with Trichuris colonization, the mechanisms underlying this transkingdom interaction have been obscure. Here, we used a multiscale microscopy approach to define the structural events associated with bacteria-mediated hatching of eggs for the murine model parasite Trichuris muris. Through the combination of scanning electron microscopy (SEM) and serial block face SEM (SBFSEM), we visualized the outer surface morphology of the shell and generated 3D structures of the egg and larva during the hatching process. These images revealed that exposure to hatching-inducing bacteria catalyzed asymmetric degradation of the polar plugs prior to exit by the larva. Unrelated bacteria induced similar loss of electron density and dissolution of the structural integrity of the plugs. Egg hatching was most efficient when high densities of bacteria were bound to the poles. Consistent with the ability of taxonomically distant bacteria to induce hatching, additional results suggest chitinase released from larva within the eggs degrade the plugs from the inside instead of enzymes produced by bacteria in the external environment. These findings define at ultrastructure resolution the evolutionary adaptation of a parasite for the microbe-rich environment of the mammalian gut.