A review of parasitic zoonoses in a changing Southeast Asia

Parasitic zoonoses are common and widely distributed in the Southeast Asian region. However, the interactions between parasites, hosts and vectors are influenced by environmental, socio-cultural and livestock production changes that impact on the distribution, prevalence and severity of disease. In this review we provide an update on new knowledge in the context of ongoing changes for the food-borne pig associated zoonoses Taenia solium and Trichinella spp., the food-borne trematodes Opisthorchis viverrini and Clonorchis sinensis, the water-borne trematodes Schistosoma spp., the vector-borne zoonotic protozoa Plasmodium knowlesi and Leishmania spp. and the soil-borne zoonotic hookworm Ancylostoma ceylanicum. These various changes need to be considered when assessing or developing regional control programs or devising new research initiatives in a changing SE Asia.     

Establishment of serological herd profiles for zoonoses and production diseases in pigs by “meat juice multi-serology”

The most important pork-borne zoonotic diseases in humans such as Salmonelloses and Yersinioses cause only latent infections in pigs. Thus, the infection of pigs does not result in apparent or palpable alterations in the pig carcasses. This is the major reason, why the traditional meat inspection with adspection, palpation and incision is not able to control the food safety risks of today. The objective of this paper is to evaluate a set of serological tests, which provides a classification of pig herds into “zoonoses risk categories” as demanded by EU law and into “herd health risk categories” by using meat juice as diagnostic specimen for ELISA tests. Serological data that were obtained by testing meat juice samples from various pig herds were analyzed as proof of the “meat juice multi-serology” concept. For that, at least 60 meat juice samples from 49 pig herds each were taken between September 2010 and March 2011 and tested for antibodies against zoonotic pathogens (Salmonella spp., Trichinella spp., Yersinia enterocolitica and Toxoplasma gondii) and against pathogens causing production diseases (Mycoplasma hyopneumoniae, influenza A virus subtype H1N1, influenza A virus subtype H3N2 and PRRSV). Apparent and true animal prevalence, herd prevalence values and intra-herd seroprevalence values as well as the predictive values for the herd and the animal prevalence values were calculated for each pathogen and each of the 49 randomly selected herds. The herd seroprevalence values (one seropositive sample per herd determined a “positive herd”) for Y. enterocolitica, Salmonella spp., T. gondii, M. hyopneumoniae and PRRSV were higher than 80%, respectively, for the influenza A viruses between 60% and 14% and for Trichinella spp. 0%. Although all herds were located in the same area in the Northwest of Germany within a radius of 250 km, the intra-herd seroprevalence values for all tested pathogens, except for Trichinella spp., varied remarkably from herd to herd. In the case of Y. enterocolitica and T. gondii the intra-herd seroprevalence values varied even from zero to 100%. This shows that a serological risk categorization of pig herds regarding zoonoses and production diseases is meaningful if used for risk-based decisions in the framework of the new meat inspection concept and as part of the herd health management system. Thus, the development of a cost-efficient, time- and labour-saving test system for simultaneously detecting various antibodies should be the next step for an extensive implementation of the meat juice multi-serology concept.     

Zoonotic intestinal parasites and vector-borne pathogens in Italian shelter and kennel dogs

This study investigated the presence of zoonotic parasites and vector-borne pathogens in dogs housed in kennels and shelters from four sites of Italy. A total of 150 adoptable dogs was examined with different microscopic, serological and molecular methods.Overall 129 dogs (86%) were positive for one or more parasites and/or pathogens transmitted by ectoparasites. Forty-eight (32%) were positive for one infection, while 81 (54%) for more than one pathogen. The most common zoonotic helminths recorded were hookworms, roundworms and Capillaria aerophila, followed by mosquito-borne Dirofilaria spp. and Dipylidium caninum. One hundred and thirteen (77.9%), 6 (4.1%) and 2 (1.4%) dogs were positive for Rickettsia spp., Leishmania infantum and Anaplasma spp., respectively.The results show that dogs living in rescue facilities from the studied areas may be infected by many zoonotic internal parasites and vector-borne pathogens, and that control measures should be implemented.     

Food-borne parasitic infections — A review

A review of food-borne parasitic infections is presented. Parasitic infections in conventional slaughtered animals and seafood (fish and shellfish) constituting a public health hazard are discussed. To the former category belong cysticercosis, echinococcosis and trichinellosis, and to the latter category belong various trematole, cestode and nematode infections. Examples of trematode infections are heterophyidiasis, transmitted to man by marine fish and Paragonimus spp. parasites, transmitted by crustaceans. Cestode infections include diphyllobothriasis transmitted by freshwater fish and fish from brackish waters. Special attention is drawn to the condition known as sparganosis. Of the nematode infections the eosinophilic granulomatous enteritis is mentioned. It is due to infections with members of the genera Anisakis, Phocanema and Contracaecum and is transmitted to man by either marine fish of crustaceans. Two other nematode infections Angiostrongylus cantonensis and Capillaria philippinensis can also be transmitted to man by marine fish.Apart from a possible direct effect of these parasites, chemical alterations in seafood resulting from the presence of parasites may also be deleterious to the consumer.Special attention is drawn to a newly developed serological detection method, the enzyme-linked immunosorbent assay, enabling not only detection of infection at the slaughter-house, but also in large herds at the farm.Strategies to control parasitic infections both in conventional slaughtered animals and in seafood are discussed.     

Sporadic endemicity of zoonotic Paragonimus in raccoon dogs and Japanese badgers from Miyazaki Prefecture,Japan

Paragonimiasis is a zoonotic trematode infection caused by Paragonimus spp. To determine the recent status of Paragonimus infections in wild animals, this study investigated Paragonimus spp. in 39 raccoon dogs and 54 Japanese badgers from March 2019 to January 2021 in Miyazaki Prefecture, and examined metacercariae in freshwater crabs. Triploid P. westermani was found in one raccoon dog (2.6%), and metacercariae were recovered from Eriocheir japonica captured near the infected animal collected. One Japanese badger (1.9%) harbored P. skrjabini miyazakii; this prevalence was lower than the approximately 30% that was reported in the 1970s. Results indicated that zoonotic Paragonimus was sporadically prevalent in wild animals. Further investigation in various animals is awaited to elucidate current wildlife reservoirs for those Paragonimus.     

The socioeconomic burden of parasitic zoonoses: global trends

Diseases resulting from zoonotic transmission of parasites are common. Humans become infected through food, water, soil and close contact with animals. Most parasitic zoonoses are neglected diseases despite causing a considerable global burden of ill health in humans and having a substantial financial burden on livestock industries. This review aims to bring together the current data available on global burden estimates of parasitic zoonoses and indicate any changes in the trends of these diseases. There is a clear need of such information as interventions to control zoonoses are often in their animal hosts. The costs of such interventions together with animal health issues will drive the cost effectiveness of intervention strategies. What is apparent is that collectively, parasitic zoonoses probably have a similar human disease burden to any one of the big three human infectious diseases: malaria, tuberculosis or HIV in addition to animal health burden. Although the global burden for most parasitic zoonoses is not yet known, the major contributors to the global burden of parasitic zoonoses are toxoplasmosis, food borne trematode infections, cysticercosis, echinococcosis, leishmaniosis and zoonotic schistosomosis. In addition, diarrhoea resulting from zoonotic protozoa may have a significant impact.     

Looks can deceive: Molecular identity of an intraerythrocytic apicomplexan parasite in Australian gliders

Two yellow-bellied gliders (Petaurus australis) had an intraerythrocytic parasite closely related to the cyst-forming coccidia (Apicomplexa: Sarcocystidae). The parasitaemia persisted for 3 months or more but was observed to clear within 3 years in captivity. The parasite appears not to significantly debilitate its infected host. Traditionally, using morphological identification, the intraerythrocytic parasite would have been classified within the Hepatozoon species typically found in red blood cells. However, molecular diagnostic techniques targeting the parasite's SSU rDNA and LSU rDNA demonstrated the unusual identity of this blood parasite and disputed its identity as a haemogregarine parasite of the genus Hepatozoon. The sequence was compared with available sequences from diverse mammalian and non-mammalian blood parasites (malaria, piroplasms, hemosporidia and sarcosporidia). The intraerythrocytic blood parasite was found to be most closely related to the cyst-forming coccidia including Besnoitia spp., Cystoisospora spp., Hammondia spp., Hyaloklossia lieberkuehni, Neospora caninum, Sarcocystis spp. and Toxoplasma gondii. The life cycle of this intraerythrocytic parasite remains unknown. The presented DNA identification demonstrates its suitability for an improved identification of blood parasites.     

Immunohistochemical identification of Toxoplasma gondii in tissues from Modified Agglutination Test positive sheep

Toxoplasma gondii is a zoonotic agent of great importance in veterinary and public health. The aim of this study was to identify T. gondii by IHC (immunohistochemistry) in different sheep tissues and to determine if an association exists between the results obtained by this method and those obtained by the Modified Agglutination Test (MAT). Tissue specimens of twenty-six sheep seroreactive for T. gondii were selected for histopathological evaluation. The presence of T. gondii was investigated in brain, liver and heart samples by IHC and a possible anti-T. gondii antibody cross reactions with other parasites. McNemar's, Chi-square and Fisher's Exact Tests were applied for the statistical analysis of the results. The analysed tissues showed at least one of the following histopathological changes: mild-to-moderate congestion, focal polymorphonuclear inflammatory infiltrate and multifocal or focal mononuclear inflammatory infiltrate. Sarcocystis spp. were identified in the histological sections from both the heart and diaphragm tissues of 88.5% (23/26) of the animals. A total of 46.2% (12/26) of the T. gondii seroreactive sheep was also positive for T. gondii by IHC in at least one organ (brain, liver or heart). The liver IHC-positivity for T. gondii was statistically equivalent to the global individual IHC-positivity, according to McNemar's test. In addition, IHC allowed the detection of T. gondii in infected animals regardless of the titration observed in the MAT. The statistical difference observed between the three organs when comparing the low titration group, suggested that the heart might be the most suitable organ to detect T. gondii infection by IHC. The IHC results in this study revealed that almost half of MAT positive animals could serve as potential sources of infection for humans because bradyzoites were identified in different tissues, regardless of the MAT titration.     

Amebae and ciliated protozoa as causal agents of waterborne zoonotic disease

The roles free-living amebae and the parasitic protozoa Entamoeba histolytica and Balantidium coli play as agents of waterborne zoonotic diseases are examined. The free-living soil and water amebae Naegleria fowleri, Acanthamoeba spp., and Balamuthia mandrillaris are recognized etiologic agents of mostly fatal amebic encephalitides in humans and other animals, with immunocompromised and immunocompetent hosts among the victims. Acanthamoeba spp. are also agents of amebic keratitis. Infection is through the respiratory tract, breaks in the skin, or by uptake of water into the nostrils, with spread to the central nervous system. E. histolytica and B. coli are parasitic protozoa that cause amebic dysentery and balantidiasis, respectively. Both intestinal infections are spread via a fecal-oral route, with cysts as the infective stage. Although the amebic encephalitides can be acquired by contact with water, they are not, strictly speaking, waterborne diseases and are not transmitted to humans from animals. Non-human primates and swine are reservoirs for E. histolytica and B. coli, and the diseases they cause are acquired from cysts, usually in sewage-contaminated water. Amebic dysentery and balantidiasis are examples of zoonotic waterborne infections, though human-to-human transmission can occur. The epidemiology of the diseases is examined, as are diagnostic procedures, anti-microbial interventions, and the influence of globalization, climate change, and technological advances on their spread.     

Meat Juice Serology and Improved Food Chain Information as Control Tools for Pork‐Related Public Health Hazards

The seroprevalence of Salmonella spp., pathogenic Yersinia spp., Toxoplasma gondii and Trichinella spp. was studied in 1353 finishing pigs from 259 farms that were allocated according to farm types: large fattening farms (≥1000 pig places), small fattening farms (< 1000 pig places) and farrow‐to‐finish farms. The antibodies were analysed with commercial ELISA kits in meat juice samples that were collected at Finnish slaughterhouses. Salmonella antibodies were rare (3% of pigs, 14% of farms) when the cut‐off optical density (OD) value 0.2 was used. Antibodies to pathogenic Yersinia spp. and T. gondii were detected in 57% of pigs and 85% of farms (OD ≥0.3) and in 3% of pigs and 9% of farms (OD ≥0.15), respectively. No antibodies to Trichinella spp. were detected (OD ≥0.3). The European Food Safety Authority (EFSA) considers Salmonella spp., Yersinia enterocolitica, T. gondii and Trichinella spp. as the most relevant biological hazards in the context of meat inspection of pigs. The seroprevalence of these important zoonotic pathogens was low in Finland, except that of Yersinia. The seroprevalence of Toxoplasma was significantly higher in pigs originating from small‐scale fattening farms (P < 0.05). Strong positive correlation was observed at the animal level between Salmonella and Yersinia seropositivity and between Salmonella and Toxoplasma seropositivity (P < 0.05). We suggest that these results reflect the level and importance of biosecurity measures applied on the farms. Meat juice serology at slaughter is a useful tool for targeting measures to control these pathogens. The information obtained from analyses should be used as part of the food chain information (FCI).     

Serological status of mares in parturition and the levels of antibodies (IgG) against protozoan family Sarcocystidae from their pre colostral foals

Protozoa from the family Sarcocystidae are agents of reproductive and neurological disorders in horses. The transmission of these protozoa may occur via horizontal or vertical means, and the frequency and potential of the later is not fully elucidated in horses. Thus, the aim of study was to correlation levels of antibodies in mares with pre colostral foals seropositive and assess the level and distribuition of antibodies against Neospora spp., Sarcocystis neurona and Toxoplasma gondii, in mares and pre colostral foals at the parturition. The blood samples were collected from mares immediately after parturition and from newborns before the ingestion of colostrum, and sera were analyzed for the presence of IgG by ELISA. It was found that 21.5%, 33.7% and 27.6% of mares were seropositive for Neospora spp., S. neurona and T. gondii, respectively; foals had antibodies at a rate of 8.3%, 6.6% and 6.6% for Neospora spp., S. neurona and T. gondii, respectively. Additionally, paired samples from mares and pre-colostral foals revealed an overall negative correlation between the serum reactivity against these three parasites and suggested that seronegative mares, or those with low to intermediate antibody levels, have a higher risk of giving birth to seropositive foals.     

Prevalence of zoonotic parasites in feral cats of Central Virginia,USA

Felis catus, the domestic cat, is the definitive host for parasites that may result in adverse health outcomes in humans. Prevalence data of zoonotic parasites in feral cats, which are free‐roaming domestic cats that are born and live in the wild, are limited. The objective of this study was to assess seroprevalence of Toxoplasma gondii antibodies and copro‐prevalence of potentially zoonotic parasites in feral cats and to evaluate risk factors for seropositivity and faecal excretion of parasites. In this cross‐sectional survey, 275 feral cats at Trap‐Neuter‐Release clinics in Central Virginia were tested for parasites via faecal flotation, direct immunofluorescence assay (faeces) and modified agglutination testing (serum). Toxoplasma gondii seroprevalence was 22.35% (95% CI: 17.47–27.86). Faecal prevalence of T. gondii‐like oocysts was 1.04% (95% CI: 0.13–3.71), Toxocara cati 58.85% (95% CI: 51.54–65.89), Ancylostoma spp. 18.75% (95% CI: 13.49–25.00), Giardia duodenalis 5.73% (95% CI: 2.89–10.02) and Cryptosporidium spp. 3.33% (95% CI: 1.37–7.24). Female cats were more likely than males to excrete faecal Ancylostoma spp. eggs (OR 2.88; 95% CI 1.34–6.17). Adults were more likely than immature cats to be seropositive (OR 2.10; 95% CI: 1.11–3.97) and to excrete faecal Ancylostoma spp. eggs (OR 2.57; 95% CI: 1.10–5.99). However, immature cats were more likely than adults to excrete T. cati eggs (OR 6.79; 95% CI: 3.31–13.90) and to excrete one or more potentially zoonotic species (OR 4.67; 95% CI: 2.28–9.55) in faeces. Results of this study have implications for human and animal health and highlight the importance of collaboration between public health, medical and veterinary communities in preventive efforts.     

Food‐borne parasitic infections ‐ old stories and new facts

Summary

A review is presented of food‐borne parasitic infections. Parasitic infections with public health hazards both from conventional slaughter animals and from seafood (fish and shellfis) are discussed.

The former category includes cysticercosis, echinococcosis, and trichinosis, the latter category covers various trematode, cestode, nematode, and possibly also protozoan infections. Examples of trematode infections are heterophyidiasis, transmitted to man by marine fish, and Paragonimus spp parasites, transmitted by crustaceans. Cestode infections include diphyllobothriasis transmitted by both fresh waterfish and fish from brackish waters. Special attention is drawn to the condition known as sparganosis. Of the nematode infections, the eosinophilic granulomatous enteritis due to the genera A nisakis, Phocanema, and Contracaecum, transmitted to man by either marine fish or crustaceans, is mentioned. Two other nematode infections. Angiostrongylus cantonensis and Capillaria philippinensis, can also be transmitted to man by marine fish.

Free living amoebae (a.o. Naegleria) may be transmitted to man via shellfish as vehicles.

Apart from a possible direct effect of these parasites, chemical alterations in seafood resulting from the presence of parasites may also be deleterious to the consumer.

Special attention is drawn to a newly developed serological detection method, the enzyme‐linked immunosorbent assay, which makes detection of infection possible not only at the slaughterhouse but also at the farm or in large herds.

Strategies to control parasitic infections both in conventional slaughter animals and in seafood are discussed.     

Food-borne parasitic infections - old stories and new facts

Summary A review is presented of food-borne parasitic infections. Parasitic infections with public health hazards both from conventional slaughter animals and from seafood (fish and shellfis) are discussed. The former category includes cysticercosis, echinococcosis, and trichinosis, the latter category covers various trematode, cestode, nematode, and possibly also protozoan infections. Examples of trematode infections are heterophyidiasis, transmitted to man by marine fish, and Paragonimus spp parasites, transmitted by crustaceans. Cestode infections include diphyllobothriasis transmitted by both fresh waterfish and fish from brackish waters. Special attention is drawn to the condition known as sparganosis. Of the nematode infections, the eosinophilic granulomatous enteritis due to the genera A nisakis, Phocanema, and Contracaecum, transmitted to man by either marine fish or crustaceans, is mentioned. Two other nematode infections. Angiostrongylus cantonensis and Capillaria philippinensis, can also be transmitted to man by marine fish. Free living amoebae (a.o. Naegleria) may be transmitted to man via shellfish as vehicles. Apart from a possible direct effect of these parasites, chemical alterations in seafood resulting from the presence of parasites may also be deleterious to the consumer. Special attention is drawn to a newly developed serological detection method, the enzyme-linked immunosorbent assay, which makes detection of infection possible not only at the slaughterhouse but also at the farm or in large herds. Strategies to control parasitic infections both in conventional slaughter animals and in seafood are discussed.     

The devil is in the details—Host disease and co‐infections are associated with zoonotic pathogen carriage in Norway rats (Rattus norvegicus)

Traditionally, zoonotic pathogen ecology studies in wildlife have focused on the interplay among hosts, their demographic characteristics and their pathogens. But pathogen ecology is also influenced by factors that traverse the hierarchical scale of biological organization, ranging from within‐host factors at the molecular, cellular and organ levels, all the way to the host population within a larger environment. The influence of host disease and co‐infections on zoonotic pathogen carriage in hosts is important because these factors may be key to a more holistic understanding of pathogen ecology in wildlife hosts, which are a major source of emerging infectious diseases in humans. Using wild Norway rats (Rattus norvegicus) as a model species, the purpose of this study was to investigate how host disease and co‐infections impact the carriage of zoonotic pathogens. Following a systematic trap and removal study, we tested the rats for the presence of two potentially zoonotic bacterial pathogens (Bartonella tribocorum and Leptospira interrogans) and assessed them for host disease not attributable to these bacteria (i.e., nematode parasites, and macroscopic and microscopic lesions). We fitted multilevel multivariable logistic regression models with pathogen status as the outcome, lesions and parasites as predictor variables and city block as a random effect. Rats had significantly increased odds of being infected with B. tribocorum if they had a concurrent nematode infection in one or more organ systems. Rats with bite wounds, any macroscopic lesion, cardiomyopathy or tracheitis had significantly increased odds of being infected with L. interrogans. These results suggest that host disease may have an important role in the ecology and epidemiology of rat‐associated zoonotic pathogens. Our multiscale approach to assessing complex intrahost factors in relation to zoonotic pathogen carriage may be applicable to future studies in rats and other wildlife hosts.     

Enteric parasites of free-roaming,owned, and rural cats in prairie regions of Canada

The objective of this study was to determine prevalence, intensity, and zoonotic potential of gastrointestinal parasites in free-roaming and pet cats in urban areas of Saskatchewan (SK) and a rural region in southwestern Alberta (AB). Fecal samples were analyzed using a modified double centrifugation sucrose flotation to detect helminth eggs and coccidian oocysts, and an immunofluorescence assay to detect Giardia and Cryptosporidium. Endoparasite prevalence was higher in samples from rural AB cats (41% of 27) and free-roaming SK cats (32% of 161) than client-owned SK cats (6% of 31). Parasites identified using morphological and molecular techniques included Toxocara cati, Toxascaris leonina, Baylisascaris-type eggs, Eucoleus aerophilus, Taenia taeniaeformis, Isospora spp., Cryptosporidium spp., and zoonotic genotype A of Giardia duodenalis. This study demonstrates significant differences in endoparasite prevalence in feline populations, and the value of molecular techniques in fecal-based surveys to identify and determine parasite zoonotic potential.     

Investigation of Zoonotic Infections Among Auckland Zoo Staff: 1991–2010

Investigation was undertaken to assess the occurrence of zoonotic infection among staff at Auckland Zoological Park, New Zealand, in 1991, 2002 and 2010. Serial cross‐sectional health surveys in 1991, 2002 and 2010 comprising a health questionnaire, and serological, immunological and microbiological analysis for a range of potential zoonotic infections were performed. Laboratory results for zoo animals were also reviewed for 2004–2010 to assess the occurrence of potential zoonotic infections. Veterinary clinic, animal handler, grounds, maintenance and administrative staff participated in the surveys, with 49, 42 and 46 participants in the 1991, 2002 and 2010 surveys, respectively (29% of total zoo staff in 2010). A small number of staff reported work‐related infections, including erysipelas (1), giardiasis (1) and campylobacteriosis (1). The seroprevalence of antibodies to hepatitis A virus and Toxoplasma gondii closely reflected those in the Auckland community. No carriage of hepatitis B virus (HBV) was detected, and most of those with anti‐HBV antibodies had been vaccinated. Few staff had serological evidence of past leptospiral infection. Three veterinary clinic staff had raised Chlamydophila psittaci antibodies, all <1 : 160 indicating past exposure. Two staff (in 1991) had asymptomatic carriage of Giardia lamblia and one person (in 2010) had a dermatophyte infection. After 1991, positive tests indicating exposure to Mycobacterium tuberculosis were <10%, comparable to the general New Zealand population. Zoo animals had infections with potential zoonotic agents, including G. lamblia, Salmonella spp., Campylobacter spp. and T. gondii, although the occurrence was low. Zoonotic agents pose an occupational risk to zoo workers. While there was evidence of some zoonotic transmission at Auckland Zoo, this was uncommon and risks appear to be adequately managed under current policies and procedures. Nevertheless, ongoing assessment of risk factors is needed as environmental, human and animal disease and management factors change. Policies and procedures should be reviewed periodically in conjunction with disease monitoring results for both animals and staff to minimise zoonotic transmission.     

Population genetics of Toxoplasma gondii: new perspectives from parasite genotypes in wildlife

Toxoplasma gondii, a zoonotic protozoal parasite, is well-known for its global distribution and its ability to infect virtually all warm-blooded vertebrates. Nonetheless, attempts to describe the population structure of T. gondii have been primarily limited to samples isolated from humans and domesticated animals. More recent studies, however, have made efforts to characterize T. gondii isolates from a wider range of host species and geographic locales. These findings have dramatically changed our perception of the extent of genetic diversity in T. gondii and the relative roles of sexual recombination and clonal propagation in the parasite's lifecycle. In particular, identification of novel, disease-causing T. gondii strains in wildlife has raised concerns from both a conservation and public health perspective as to whether distinct domestic and sylvatic parasite gene pools exist. If so, overlap of these cycles may represent regions of high probability of disease emergence. Here, we attempt to answer these key questions by reviewing recent studies of T. gondii infections in wildlife, highlighting those which have advanced our understanding of the genetic diversity and population biology of this important zoonotic pathogen.     

Observations on the occurence and specificity of anti-bodies produced by infected hosts against the acetyl-cholinesterase present in some common gastrointestinal nematode parasites

Sera from hosts infected with a variety of nematodes were examined for the presence of antibodies against nematode acetylcholinesterase (AChE). Antibodies were detected in the serum from hosts infected with Oesophagostomum spp., Ostertagia spp. and Trichostrongylus spp., but not in serum from hosts infected with Cooperia pectinata or Haemonchus spp., Toxocara spp. or Trichuris vulpis. In those infections in which anti-AChE antibodies were found, some individual animals failed to produce detectable antibodies. The enzyme appeared to possess antigenic specificity at the genus but not the species level.     

Serological evidence of Anaplasma spp., Borrelia burgdorferi and Ehrlichia canis in dogs from the Republic of Korea by rapid diagnostic test kits

BackgroundEmergent and re-emergent canine tick-borne infections are attracting increasing attention worldwide. The rise in pet ownership and the close relationship between dogs and their owners are the most concerning factors because dogs may act as competent reservoirs for human tick-transmitted infectious agents.ObjectivesThis study contributes to the epidemiological surveillance of canine tick-transmitted infections with zoonotic risk in the Republic of Korea (ROK) by investigating the seroprevalence of the pathogens, Anaplasma spp., Borrelia burgdorferi, and Ehrlichia canis.MethodsFour hundred and thirty whole blood samples from domestic dogs were collected in seven metropolitan cities and nine provinces in the ROK and tested using SensPERT Ab test kits (VetAll Laboratories®) to detect seroreactive animals.ResultsThe seroprevalence rates identified were 9.8% (42/430) for Anaplasma spp., 2.8% (12/430) for B. burgdorferi, and 1.4% (6/430) for E. canis. The risk factors evaluated in this study that could be associated with the development of a humoral immune response, such as sex, age, and history of tick exposure, were similar. There was only one exception for dogs seroreactive to Anaplasma spp., where the risk factor “tick exposure” was statistically significant (p = 0.047).ConclusionsThis serological survey exhibited the widespread presence of Anaplasma spp., B. burgdorferi, and E. canis throughout the ROK. Hence, dogs may play a key role as the sentinel animals of multiple zoonotic infectious agents in the country.