Prevalence of intestinal parasites in street dogs (Canis lupus familiaris) with highlights on zoonosis in Lalitpur, Nepal

BACKGROUND

The presence of intestinal parasites influences the growth and well-being of canids. Additionally, infected dogs and their faeces with considerably higher eggs/oocysts released per gram (epg/opg) of zoonotic parasites contribute to parasitic spillover to humans, domestic animals and sympatric wildlife.

OBJECTIVES

The current study aimed to reveal the prevalence of intestinal parasites (protozoa and helminths) and to list the zoonotically significant parasites in free-roaming street dogs in Lalitpur Metropolitan City, Nepal.

METHODS

Fresh faecal samples (n = 332) were collected from feral dogs of varying ages and sexes and transported to the research laboratory. The copro microscopic examination was carried out via direct wet mount, formalin ethyl acetate sedimentation, saturated salt flotation, acid-fast staining and sporulation techniques.

RESULTS

Coproscopy revealed an overall 95.7% (318/332) prevalence rate with 23 diverse species of intestinal parasites (10 protozoa and 13 helminths). Among them, 5 protozoa and 11 helminths possessed zoonotic potential, and their overall prevalence was 92.5%. Helminth's overall prevalence was double that of the protozoa (87.7% vs. 43%). Polyparasitism was dominant over mono parasitism (79.5% vs. 16.3%), and co-infection of up to seven species of parasites at a time was recorded.

CONCLUSIONS

Urban street dogs harboured a higher prevalence of intestinal parasites that varied with age and sex. Since most of the reported parasites are zoonotic, dog density and parasitic richness indicate a greater spillover risk to humans and domestic animals. Furthermore, this study also provides appropriate 'baseline' data for assessing effective control measures against parasitic infestations among street dogs and controlling their transmission to humans.

Prevalence of Zoonotic Gastrointestinal Helminth Parasite among Dogs in Suryabinayak, Nepal

Dogs are popular pets around the world and have always had a very close relationship with humans. Zoonotic gastrointestinal helminth parasites are a great threat to both stray and pet dogs. This study was carried out to determine the prevalence of zoonotic gastrointestinal helminths in dogs. 400 samples were collected, including 200 from pet dogs and 200 from stray dogs. The samples from pet dogs were collected from the ground immediately after voiding with the help of the owner, whereas stray dogs were caught by using a dog catcher, and the samples were collected directly from the rectum by using a gloved index finger. All collected samples were examined under a microscope using sedimentation and flotation techniques. The overall prevalence of infection was found to be 59.50%, with a significantly higher prevalence in stray dogs (70%) than that in pet dogs (49%). Ancylostoma spp., Toxocara spp., Trichuris spp., Capillaria spp., Dipylidium caninum, and Taenia/Echinococcus spp. were six different species found in the current study. The study showed the highest prevalence of Ancylostoma spp. (49.16%) and the least prevalence of Capillaria spp. (0.84%). In the age-wise study, puppies had a significantly high infection rate (86.96%). Similarly, we recorded a significantly higher prevalence of intestinal helminths among nondewormed pet dogs (78.65%) than among dewormed pet dogs (25.23%). This study highlights the severe environmental contamination shed by dogs, causing a higher risk of zoonotic transmission. It indicates the urgent need to manage these parasites in dogs and educate the public on how to care for their pets and the parasites they shed.

First Molecular Identification of Ancylostoma Species in Dogs in a Rural Tea Estate Community in Sri Lanka and the Detection of Other Zoonotic Gastro-intestinal Parasites

PURPOSE

Ancylostoma spp. causing canine hookworm infections are distributed worldwide with a high prevalence in the South Asian region. Here, we report the first molecular identification of the canine hookworm infecting the dogs in Sri Lanka.

METHOD

Fresh faecal samples were collected from free-roaming dogs in tea estate communities in Talawakelle, processed and microscopically analysed for gastro-intestinal parasites. The common dog hookworm Ancylostoma sp. was further investigated using molecular diagnostic tools including PCR, sequencing, and phylogenetic analyses.

RESULTS

Of the individual dogs sampled, 97.0% (97/100) were positive for GI parasites, identifying 14 species, all of which were zoonotic. Entamoeba sp. (58.0% (58/100)) was the most prevalent infection and Ancylostoma sp. (45.0% (45/100)) was the most prevalent helminth infection. Overall, helminth prevalence was higher in female dogs (92.5% (37/40)) than male dogs (73.3% (44/60)), potentially due to immune suppression during pregnancy and lactation. The prevalence and burden of Toxocara canis was higher in puppies (≤ 1 year) (68.8%(11/16); Chi-square test; χ² = 20.912, p < 0.001 and FEC = 5.91; Mann-Whitney U test; p < 0.001), possibly due to vertical trans-mammary or trans-placental transmission of infective larvae. This study also presents the first record of Hymenolepis sp. from dogs in Sri Lanka. Ancylostoma sp. was molecularly confirmed as A. caninum.

CONCLUSION

The local variant of A. caninum was phylogenetically unique and showed 99.2% similarity to that from India. The high prevalence of zoonotic GI parasites with public health significance highlights the importance of improving community well-being, veterinary care for dogs, and public awareness on zoonoses.

Prevalence of Intestinal Helminth Infections of Stray Dogs of Public Health Significance in Lagos Metropolis, Nigeria

Globally, stray dogs have been a major source of zoonoses such as cutaneous larval migrans, visceral larval migrans and hydatidosis. These dogs are recognized as being a major public health problem where their population is unchecked. This study was conducted to determine the prevalence of intestinal helminth parasites of stray dogs in Lagos metropolis. Stools of 96 stray dogs were examined microscopically for ova of these parasites using centrifugation flotation method. Four species of intestinal helminths were identified. The overall prevalence of helminths infection was 61.4%, with Ancylostoma caninum having a prevalence of 62.5%, Toxocara canis 20.8%, Dipylidium caninum 18.7% and Strongyloides stercoralis 2.0%. T. canis had the highest worm burden of 1,250 egg per gram (EPG) while S. stercoralis had the least (100 EPG). The areas with the most helminth infections were Yaba (n=12, X̄=1.58, SD=0.793), Agege (n=11, X̄=1.73, SD=0.786) and Ikotun (n=11, X̄=1.45, SD=0.820). S. stercoralis was only found in samples obtained from Mushin and Ikorodu. Most of the stool samples obtained from this study had mixed infections, 83.3% were infected with three helminth species, 8.3% were infected with four helminth species and none had double infection. Mushin had the most mixed infections (n=4, X̄=1.900, SD=1.101) while Obalende had the least (n=1, X̄=1.000, SD=0.000). Most of the intestinal helminth parasites identified in this study are zoonotic and thus pose a public health problem. Environmental factors seem to influence the health condition of these dogs, thus concerted efforts should be made to reduce the growing population of stray dogs on the street of Lagos.

Gastrointestinal helminths in dog feces surrounding suburban areas of Lower Dir district, Pakistan: A public health threat

Data on environmental contamination of the parasites of zoonotic importance is scarce in Pakistan. Soil contamination with feces of dogs hide infective stages of the parasite represents a health-risk to humans. This study was aimed to assess the eggs of gastrointestinal parasites of stray dogs and household dogs in lower Dir district, Pakistan with special consideration to those that can be spread to humans. One hundred and fifty two stool specimens from (stray dogs=90 and household dogs=62) were collected. The helminth eggs were processed by direct smear method and centrifugation techniques and identified by microscopic examination. Of the total examined dogs 26.8% (n=41 /152) were found to be infected with one or more intestinal parasites. The intestinal helminths detected were Dipylidium caninum (n =18, 11.8%), followed by Toxocara canis (n =16, 10.5%), Taenia spp., (n=10, 6.57%) Ancylostoma caninum (n=6, 3.94), Toxascaris spp., Capillaria spp., and Trichuris vulpis (n=2, 1.31% each) in order of their prevalence. Pattern of infection revealed that 27 (65.8%) dogs have single, 13(31.7%) double and 1(2.43%) triple infection. The stray dogs were highly infected 34.4% (n=31) than house hold dogs 16.1% (n=10). The prevalence of infection with intestinal parasites was significantly different among these two groups (p = 0.0097). This study highlight a severe environmental contamination by frequent parasitic stages infectious to humans. There is a higher risk of zoonotic transmission from dogs which indicate an immediate need for the controlling of these parasites and educating the public to take wise action relating to the parasites and pets.

Zoonotic intestinal parasites of carnivores: A systematic review in Iran

AIM

Parasitic infections, especially of the zoonotic-parasitic type, are the most important health, economic, and social problems in developing countries, including Iran. The aim of this study was to review systematically the available data on gastrointestinal parasites of carnivores in Iran and their ability to infect humans.

MATERIALS AND METHODS

Studies reporting intestinal parasites of carnivores were systematically collected from nine electronic English and Persian databases and Proceedings of Iranian parasitology and veterinary congresses published between 1997 and 2015. A total of 26 studies issued from 1997 to 2015 met the eligibility criteria.

RESULTS

The pooled proportion of intestinal parasites of carnivores was estimated as 80.4% (95% confidence interval=70.2-88.8%). The overall prevalence of gastrointestinal parasites in dogs, cats, foxes, and jackals were 57.89%, 90.62%, 89.17%, and 97.32%, respectively. Dipylidium caninum (20.45%), Toxocara spp. (18.81%), Taenia hydatigena (15.28%), Mesocestoides lineatus (11.83%), Echinococcus granulosus (10%), and Toxascaris leonina (8.69%) were the most frequently observed parasites.

CONCLUSION

High prevalence rates of zoonotic intestinal parasites of carnivores particularly Echinococcus spp. and Toxocara spp. increase the risk of acquiring zoonotic infections such as cystic hydatid, alveolar cysts, and visceral or ocular larva migrants in Iranian people. Therefore, it is essential for public health centers to develop more effective control strategies to decrease infections rates in carnivores' populations.