Human infections by Hymenolepis diminuta in Europe: a case report and literature review

We performed a review of published and gray literature of human Hymenolepis diminuta cases across Europe up to July 2022. Of all detectable publications and records, we further analyzed only those that contained demographic, clinical or epidemiological data regarding the infected subjects. Additionally, one case of hymenolepiasis in a 16-mo-old boy living in the urban part of Belgrade was included in the analysis. Published studies were based in 13/50 European countries and identified 104 laboratory-confirmed cases in total. Almost one-half (49%) of all cases originated from Mediterranean countries. Among symptomatic children, the infection most often manifested with diarrhea, abdominal pain, allergic reaction and behavioral changes. The diagnosis was made by the detection and identification of H. diminuta eggs or parts of strobila in stool samples, although cases of misdiagnosis were also reported. The parasite clearance was established with praziquantel or niclosamide, while the administration of albendazole or mebendazole led to unfavorable results. Future multicentric prospective studies focused on infection screening and the gathering of detailed sociodemographic and clinical data could provide an updated insight into the true distribution and characteristics of H. diminuta infection across Europe.

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

BACKGROUND

Eucoleus aerophilus (syn. Capillaria aerophila) is a nematode with a worldwide geographical distribution. It causes a disease called lung capillariosis by affecting the respiratory tract of wild and domestic animals, and has also occasionally been described in humans. Despite steady increases in knowledge of the morphology of this neglected parasite, many aspects are still poorly understood. Epidemiological data regarding, for example, geographic distribution, range of hosts, clinical relevance and the actual zoonotic potential of this nematode are scarce and incomplete.

METHODS

This article is a systematic review based on the screening of three databases (PubMed, Web of Science and Science Direct) to identify eligible studies published from 1973 to the end of 2022.

RESULTS

From a total of 606 studies describing the occurrence of E. aerophilus, 141 articles from 38 countries worldwide were included in this meta-analysis, all of which presented results obtained mainly with flotation and necropsy. Due to the occurrence of E. aerophilus in many different species and different matrices (lungs and faeces), we decided to conduct the meta-analysis separately for each species with a given matrix. This systematic review confirmed the status of the Red fox as the main reservoir and main transmitter of E. aerophilus (average prevalence of 43% in faeces and 49% in lungs) and provided evidence of a higher prevalence of E. aerophilus in wild animals in comparison to domestic animals, such as dogs (3% in faeces) and cats (2% in faeces and 8% in lungs). Previous studies have investigated many host-related factors (age, sex, environmental/living conditions) in relation to the prevalence of E. aerophilus, but they show wide variations and no simple relationship has been demonstrates. Furthermore, mixed infections with other pulmonary nematodes, such as Crenosoma vulpis and/or Angiostrongylus vasorum, are reported very frequently, which greatly complicates the diagnosis.

CONCLUSIONS

This systematic review focused on identifying data gaps and promoting future research directions in this area. To the best of our knowledge, this is the first systematic review that evaluates and summarizes existing knowledge on the occurrence and prevalence of E. aerophilus in wild and domestic animals originating from different geographical locations worldwide.

Zoonotic intestinal helminthes diagnosed in a 6-year period (2015-2020) in privately owned dogs of sub-urban and urban areas of Italy

Intestinal helminthes of dogs have a relevant role for health and welfare of canine populations and many of them are zoonotic. Thus, a constant surveillance is pivotal to safeguard companion dogs and human health. Data from faecal examinations of pet dogs obtained in the last six years during the routine activity of the laboratory of Parasitology and Parasitic diseases of the University Teaching Veterinary Hospital of the University of Teramo, Italy, are here reported. From 2015 to 2020 a total of 1083 individual faecal samples from privately owned dogs were examined using conventional copro-microscopic techniques. Endoparasite elements were found in 278 (25.7%) dogs, and among them, eggs of intestinal zoonotic helminthes were detected in 184 (17%) samples. The most common zoonotic parasites were Toxocara canis and hookworms (8.9% positivity rate for both). Most dogs (88%) were positive for a single zoonotic parasite while 12% of the positive animals harbored two or more zoonotic helminthes. A statistical analysis showed a significant association between dogs with less than one year of age and positivity to at least one intestinal zoonotic helminth, and that infections by T. canis are significantly more prevalent in dogs under one year of age. Despite being well known in canine clinical practice, these results indicate that zoonotic helminthes are still frequent in owned dogs. Thus, increased awareness of veterinary practitioners and pet owners is necessary to implement current diagnostic and control strategies to minimize the risk of zoonotic transmission of intestinal helminthes.

Efficacy of milbemycin oxime/afoxolaner chewable tablets (NEXGARD SPECTRA®) against Capillaria aerophila and Capillaria boehmi in naturally infected dogs

BACKGROUND

Capillaria aerophila and Capillaria boehmi parasitize the respiratory system of wild and domestic carnivores. Capillaria aerophila inhabits the trachea and bronchi of dogs and cats, while C. boehmi affects the nasal cavities and sinuses of dogs. In dogs the infection may be subclinical or characterized by varying respiratory distress.

METHODS

The present study evaluated the efficacy of an oral formulation containing milbemycin oxime and afoxolaner (NEXGARD SPECTRA^®) in dogs naturally infected with C. aerophila and/or C. boehmi from three enzootic areas of Italy. Dogs were enrolled pending fecal examination and molecular confirmation of respiratory capillarioses. Dogs were allocated in two groups: Group 1 (G1, 25 dogs), treated with a negative control product with no anthelmintic activity (afoxolaner, NEXGARD^®), and Group 2 (G2, 26 dogs), treated with NEXGARD SPECTRA^®. At the day of treatment administration (Day 0), all dogs were clinically examined. Dogs were again subjected to clinical and fecal examinations at Days 28 (± 4) and 56 (± 2). The primary criterion for treatment efficacy was the reduction of fecal Capillaria egg counts in G2 compared with G1. The regression of/recovery from baseline clinical signs was considered as a further efficacy criterion.

RESULTS

Percentage reduction of fecal Capillaria egg counts in the NEXGARD SPECTRA^® group compared to the control group was > 97% on Day 28 and 100% on Day 56, respectively (p < 0.05 for both time points). Twelve of the 13 dogs in the NEXGARD SPECTRA^® group with respiratory signs prior to treatment were free of clinical signs at the end of the study. Conversely, the six control group dogs with respiratory signs prior to treatment remained symptomatic.

CONCLUSIONS

Results of the present study showed that NEXGARD SPECTRA® was safe and highly efficacious in the reduction of C. aerophila and C. boehmi eggs after one treatment with a complete reduction of the egg output after the second administration associated with a recovery from respiratory signs.

Occurrence of canine and feline extra-intestinal nematodes in key endemic regions of Italy

Extra-intestinal nematodes of companion animals are of growing concern in veterinary medicine for their pathogenic potential and the current expansion throughout Europe. The present study has evaluated the occurrence of major canine and feline extra-intestinal nematodes in regions of Italy having epidemiological relevance. Associations of various recorded parameters related to the examined animals have been statistically evaluated, along with a comparative analysis with the most recent epidemiological data. Overall, 1055 dogs and 1000 cats were tested. Among extra-intestinal nematodes Angiostrongylus vasorum was the most common in dogs followed by Capillaria aerophila and Dirofilaria spp.; Aelurostrongylus abstrusus was the most recorded parasite in cats, followed by C. aerophila and Troglostrongylus brevior. The statistical analysis revealed that outdoor access is associated with A. vasorum, A. abstrusus and T. brevior infections, that were also more prevalent in animals with cardio-respiratory signs. Moreover, cats aged less than 12 months had more chances to be infected by lungworms. The data herein presented confirm the occurrence and the possible risk of expansion of different extra-intestinal parasitoses of dogs and cats in Italy, underlining the importance of a constant epidemiologic vigilance and of appropriate control methods.

Angiostrongylus vasorum infection in dogs from a cardiopulmonary dirofilariosis endemic area of Northwestern Italy: a case study and a retrospective data analysis

Background

In Italy, Angiostrongylus vasorum, an emergent parasite, is being diagnosed in dogs from areas considered free of infection so far. As clinical signs are multiple and common to other diseases, its diagnosis can be challenging. In particular, in areas where angiostrongylosis and dirofilariosis overlap, a misleading diagnosis of cardiopulmonary dirofilariosis might occur even on the basis of possible misleading outcomes from diagnostic kits.

Case presentation

Two Cavalier King Charles spaniel dogs from an Italian breeding in the Northwest were referred to a private veterinary hospital with respiratory signs. A cardiopulmonary dirofilariosis was diagnosed and the dogs treated with ivermectin, but one of them died. At necropsy, pulmonary oedema, enlargement of tracheo-bronchial lymphnodes and of cardiac right side were detected. Within the right ventricle lumen, adults of A. vasorum were found. All dogs from the same kennel were subjected to faecal examination by FLOTAC and Baermann’s techniques to detect A. vasorum first stage larvae; blood analysis by Knott’s for Dirofilaria immitis microfilariae, and antigenic tests for both A. vasorum (Angio Detect™) and D.immitis (DiroCHEK® Heartworm, Witness®Dirofilaria). The surviving dog with respiratory signs resulted positive for A. vasorum both at serum antigens and larval detection. Its Witness® test was low positive similarly to other four dogs from the same kennel, but false positive results due to cross reactions with A. vasorum were also considered. No dogs were found infected by A. vasorum.

Eventually, the investigation was deepened by browsing the pathological database of Veterinary Pathology Laboratories at Veterinary School of Milan University through 1998–2016, where 11 cases of angiostrongylosis were described. Two out of 11 dogs had a mixed infection with Crenosoma vulpis.

Conclusion

The study demonstrates the need for accurate surveys to acquire proper epidemiological data on A. vasorum infection in Northwestern Italy and for appropriate diagnostic methods. Veterinary clinicians should be warned about the occurrence of this canine parasite and the connected risk of a misleading diagnosis, particularly in areas endemic for cardiopulmonary dirofilariosis.