Companion animal parasitology: a clinical perspective

Babesia bigemina and Theileria annulata infections in cattle: molecular detection, phylogenetic analysis, and assessment of risk factors

Babesia bigemina and Theileria annulata are tick-borne protozoans that cause piroplasmosis in cattle, resulting in huge damages to the livestock industry. The prevalence of these infections depends on various intrinsic and extrinsic risk factors. In Pakistan, there is no information regarding the molecular characterization of Babesia bigemina and the risk factors associated with piroplasmosis. This study aimed to molecularly characterize Babesia spp. and Theileria spp. infecting various cattle breeds in Khyber Pakhtunkhwa, Pakistan, and to shed light on risk factors associated with these infections. Altogether, 219 blood samples were collected from various symptomatic cattle breeds, including Holstein Friesian (65.3%; 143/219), Jersey (21.5%; 47/219) and Sahiwal (13.2%; 29/219). Isolated genomic DNA from these blood samples was used in PCR for the amplification of the 18S rRNA fragment of apicomplexan parasites. Obtained 18S rDNA sequences from cattle hosts showed 99.5% identity with B. bigemina, or 100% with T. annulata. Having an overall infection rate of 61.6% (135/219), the highest infection rate was recorded for T. annulata (43.8%; 95/219), followed by B. bigemina (18.3%; 40/219). Phylogenetic analysis of 18S rDNA sequences revealed that B. bigemina clustered with corresponding species reported from Bolivia, and South Africa, while T. annulata grouped with same species from Italy, India, and Turkey. Among the different risk factors, the breed, season, and tick infestation were found to have a significant (P < 0.05) association with the piroplasmid infections. The information obtained in this study can be employed for effective surveillance and control of babesiosis and theileriosis in Pakistan. In addition to confirming our previous molecular detection of T. annulata in cattle, this study provides the first molecular surveillance and phylogenetic position of B. bigemina and associated risk factors in the study region.

Prevalence of zoonotic (brugian) filariasis in Asia: A proportional meta-analysis

Lymphatic filariasis is a public health problem and targeted for global elimination. WHO recommends mass drug administration to interrupt transmission of the parasites involved. There are concerns that transmission interruption may be difficult in areas of zoonotic filarial infections. This study aimed to estimate the pooled prevalence of zoonotic brugian filariasis, and to compare the pooled prevalence of brugian filariasis in human and animal populations in the same area based on available studies. A comprehensive literature search was conducted in health-related electronic databases (PubMed, Ovid MEDLINE, Index Medicus, google scholar). A random-effect meta-analysis of the pooled overall prevalence of filariasis in animal populations was conducted. Sixteen studies from four different Asian countries were identified. Studies were conducted most frequently in Thailand (n = 7), followed by Malaysia (n = 5), India (n = 3), and Sri Lanka (n = 1). Regardless of animal group, the pooled overall prevalence of animal Brugia infections was 13% (95%CI: 7-21%, I2:98%, 16 studies). On stratification, the pooled overall prevalence in the animal population was 19% (95%CI: 1-50%, I2: 99%, 3 studies) in India, 8% (95%CI: 2-7%, I2: 97%, 5 studies) in Malaysia, and 13% (95%CI: 7-20%, I2: 94%, 7 studies) in Thailand. The prevalence in the animal population was 17% (95%CI: 13-21%, 1 study) in Sri Lanka. The pooled overall prevalence of Brugia malayi was 13% (95%CI: 7-21%, I2:98%, 12 studies), while for Brugia pahangi this was 12% (95%CI: 7-19%, I2:86%, 7 studies). Regardless of animal group, geographic area, or diagnostic test, the prevalence of B. malayi was consistently high. On stratification by animal category, the pooled overall prevalence was 10% (95%CI: 6-14%, I2:92%, 13 studies) in cats, 12% (95%CI: 2-28%, I2: 99%, 6 studies) in dogs, and 55% (95%CI: 47-63%, 1 study) in leaf-eating monkeys. The findings show the extent of zoonotic Brugiainfections in domestic cats and dogs, suggesting that these animals are potential reservoirs for human brugian filariasis in the study countries. To substantiate this with more accuracy, future well designed whole genomic sequencing of individual mf collected from humans and B. malayi infected animals in the same area are needed.

An unusual case of Brugia sp. infection in a dog from Alberta, Canada

Brugia is a vector-transmitted nematode that is commonly known for its zoonotic significance of causing lymphatic filariasis in Asia and Oceanic regions of the world. In addition to public health concerns, Brugia species have been known to infect domestic animals, including dogs and cats. However, information is scarce regarding genus Brugia in North America, and rare infections have been noted in domestic cats, humans, and other wild mammals. Herein, we document the first reported case of a Brugia species infection in a dog from North America and the first molecular characterization of the species in question. A three-year-old German Shepard from Alberta, Canada presented to a local veterinary clinic with a facial subcutaneous nodule that was surgically excised. Histopathology identified an enlarged buccal lymph node containing small foci of eosinophilic and granulomatous inflammation within the cortex and capsule. This inflammation was associated with adult filarioid nematodes localized within lymphatic vessels or adjacent connective tissue. Genomic DNA was extracted from formalin-fixed paraffin-embedded tissue, and PCR targeting the Hha1 repeat and the partial cytochrome oxidase c subunit 1 (cox1) of the mitochondrial DNA confirmed parasite identity as Brugia sp. While we can rule out B. beaveri being the causative agent, we cannot exclude B. lepori infection or a third uncharacterized Brugia species. Veterinarians and physicians should be made aware of North American Brugia infections and their possible health concerns.

Geographic Spatial Distribution Patterns of Dirofilaria immitis and Brugia pahangi Infection in Community Dogs in Chiang Mai, Thailand

Simple Summary

Filariasis is emerging as a public health concern for humans, dogs, cats, and other wildlife species, and is frequently found in southeast Asian countries. The present study confirmed the species of filarial nematodes in free-roaming dogs from temple communities. Two species were found: Dirofilaria immitis infection and, for the first time, Brugia pahangi. The occurrence of the two species was comparable. Geographic spatial distribution revealed the abundance of D. immitis and B. pahangi in the central areas at altitudes less than 400 m. However, at higher altitudes between 400 and 800 m, we found a significantly higher number of B. pahangi infections than D. immitis infections. In conclusion, D. immitis and B. pahangi were the most common filarial infections found in community dogs in Northern Thailand. Dogs might be an important reservoir for B. pahangi in that region. The population dynamics of the mosquito vector of B. pahangi across altitudinal gradients merits further study.

Abstract

Filariasis is emerging as a public health concern in tropical and subtropical areas. Filariasis is an endemic problem commonly found in southeast Asian countries. Using the PCR-restriction fragment length polymorphism (PCR-RFLP) of the ITS1 region with Vsp I, the overall prevalence rates of Dirofilaria immitis (12.2% (41/337); 95% confidence interval: 9.1–16.1%) and Brugia pahangi (8.3% (28/337); 95% confidence interval: 5.8–11.8%) were determined based on 337 free-roaming community dogs from 20 districts in Northern Thailand. Microfilaremia was found in only 6.2% of dogs (21/337). Co-infection with D. immitis and B. pahangi was observed in two dogs. Of the 215 blood samples examined using a Canine Heartworm Ag Kit, only 3.72% (eight dogs) were D. immitis antigen positive. Among these eight, six dogs had occult D. immitis infections. In terms of geographic distribution, we found the abundance of D. immitis and B. pahangi in the central areas at altitudes less than 400 m to be 12.1% and 10.3%, respectively. In contrast, at higher altitudes between 400 and 800 m, a significantly higher number of B. pahangi compared with D. immitis infected individuals were observed at 14.29% and 4.1%, respectively. In conclusion, D. immitis and B. pahangi were the most common filarial infections found in community dogs in Northern Thailand. Dogs might be an important reservoir of B. pahangi in that region. Increasing awareness and concern and including proper deworming programs for community dogs should be endorsed to reduce the transmission risk. Additionally, the population dynamics of the mosquito vector of B. pahangi across altitudinal gradients deserved further investigation.

A Multi-Sectoral Approach Improves Early Child Development in a Disadvantaged Community in Peru: Role of Community Gardens, Nutrition Workshops and Enhanced Caregiver-Child Interaction: Project "Wawa Illari"

Background: Multi-dimensional monitoring evaluation and learning strategies are needed to address the complex set of factors that affect early child development in marginalized populations, but few studies have explored their effectiveness.

Objective: To compare improvement of health and development of children 0–3 years between intervention communities (IC) and control communities (CC) from peripheral settlements of Lima. Sequential interventions included: (1) home and community gardens, (2) conscious nutrition, and (3) parenting workshops following the International Child Development Program (ICDP).

Methods: Interventions were delivered by community health promoters (CHPs) using a “step-by-step” learning system. Both IC and CC were monitored before the interventions began, at 8 and 12 months (n = 113 IC and 127 CC children). Data were collected on household characteristics, diet, food security, health indicators (history of diarrhea and respiratory infections, hemoglobin, intestinal parasites, anthropometry), caregiver-child interactions and stress, and achievement of Pan-American Health Organization age-specific developmental milestones. Stepwise multiple logistic regressions were used to determine if the interventions affected food insecurity, as well as motor, social/cognitive and language delays.

Results: At baseline, 2.6% were categorized as “suspected developmental delay” and 14.2% were on “alert for development delay.” Food insecurity, diarrhea and respiratory infections were lowered following the interventions. Through the “step-by-step” approach, caregivers in IC gained skills in gardening, conscious nutrition and parenting that reduced the risk of food insecurity [Adjusted Risk Ratio = 0.20 (95% CI: 0.08–0.51)] and language delay [0.39 (0.19–0.82)] but not motor or social/cognitive delay. Use of a multiple micronutrient supplement decreased the risk of motor delay [0.12 (0.03–0.56)], but more pets were associated with higher risk of motor [3.24 (1.47–7.14)] and social/cognitive delay [2.72 (1.33–5.55)], and of food insecurity [1.73 (1.13–2.66)].

Conclusion: The combined interventions delivered by CHPs helped to mitigate the impact of adversity on food insecurity and language delay. Additional improvements may have been detected if the interventions had continued for a longer time. Our results indicate that control of infections and pets may be needed to achieve measurable results for motor and social/cognitive development. Continuous monitoring facilitated adjusting implementation strategies and achieving positive developmental outcomes.

Occurrence and genotypes of Cryptosporidium spp., Giardia duodenalis, and Blastocystis sp. in household, shelter, breeding, and pet market dogs in Guangzhou, southern China

Cryptosporidium spp., Giardia duodenalis, and Blastocystis sp. are common intestinal protozoans that infect humans and animals worldwide. A survey that assessed the prevalence, molecular characteristics, and zoonotic potential of these pathogens was conducted on a variety of dogs in Guangzhou, southern China. A total of 651 canine stool samples from household (n = 199), shelter (n = 149), breeding (n = 237), and pet market dogs (n = 66) were collected from eight districts in Guangzhou. Cryptosporidium spp., Giardia duodenalis, and Blastocystis sp. were detected by PCR amplification of the SSU rRNA gene. Giardia duodenalis-positive specimens were further assigned into assemblages using the glutamate dehydrogenase gene. Cryptosporidium spp., G. duodenalis, and Blastocystis sp. were found in 21 (3.2%), 20 (3.1%), and 35 (5.4%) samples, respectively. The overall prevalence of shelter dogs (40.28%, 60/149) was significantly higher than that of household (3.0%, 6/199), breeding (2.1%, 5/237), and pet market dogs (7.5%, 5/66) (χ² = 154.72, df = 3, P < 0.001). Deworming in the past 12 months had a strong protective effect on the risk of contracting parasite infections (P < 0.001). No significant differences were detected between age or sex groups (P > 0.05). Dog-specific C. canis (n = 19) and zoonotic C. parvum (n = 2) were the only two Cryptosporidium species. Sequence analysis revealed the presence of three G. duodenalis assemblages: dog-specific assemblages D (n = 14) and C (n = 5), and cat-specific F (n = 1). Zoonotic Blastocystis ST3 (n = 28) was the dominant subtype, followed by ST1 (n = 6) and ST10 (n = 1). To our knowledge, this is the first large-scale investigation on the occurrence and molecular characteristics of Blastocystis sp. in dogs in China. Our results indicated that the dogs seemed to play a negligible role as reservoirs for Cryptosporidium spp. and G. duodenalis transmission to humans, but they are potential novel suitable hosts of Blastocystis sp. A strict sentinel surveillance system of dogs should be established to minimise the zoonotic risk of spreading blastocystosis among humans and dogs.

Seroprevalence of Canine Ehrlichiosis and Microscopic Screening for Canine Babesiosis in Dogs in Harare, Zimbabwe, 2016-2017

A cross-sectional study was done to determine ehrlichiosis seroprevalence and babesiosis prevalence in dogs that were presented to selected veterinary clinics in Harare. Sera from randomly selected dogs were tested for antibodies to Ehrlichia spp. using an enzyme-linked immunosorbent assay while microscopy of peripheral blood smears was used to confirm babesiosis. Overall, 75.2% (88/117, 95% CI: 66.2–82.5) of sera samples tested were positive to Ehrlichia spp. antibodies while the prevalence of canine babesiosis was 47.9% (56/117, 95% CI: 38.6–57.3). Age, breed, and sex were found not to be associated with the two disease conditions (p > 0.05). Most of the dogs with babesiosis (82.1%, 46/56) were also positive to Ehrlichia spp. antibodies. Hypoalbuminaemia (53.8%, 63/117), anaemia (53.0%, 62/117) and thrombocytopaenia (40.2%, 47/117) were the most common laboratory findings. Thrombocytopaenia and hypoalbuminaemia was more pronounced in dogs with babesiosis only while anaemia was more marked in dogs with babesiosis and positive to Ehrlichia spp. antibodies.

Dirofilaria hongkongensis - A first report of potential zoonotic dirofilariosis infection in dogs from Tamil Nadu

Dirofilariosisis, is a mosquito borne anthropo-zoonotic disease caused by the filarial nematodes of the genus Dirofilaria. The current paper reports a species of Dirofilaria, which has not been recorded in Tamil Nadu, in addition to differentiating it from the existing species of Dirofilaria spp. through morphological and molecular techniques. Micrometry of the microfilaria detected by Knott's technique as well as in Giemsa stained blood smears revealed that the length was on an average 280 μm to 310 μm whereas the width was 5 to 8 μm. The microfilariae were unsheathed with blunt heads and tapering tails. For molecular confirmation, the blood sample was subjected to genomic DNA isolation. PCR amplification using specific primers for D. hongkongensis was carried out using thermal cycler with the isolated genomic DNA as template. Molecular analyses revealed the band size of about 230 bp which confirmed the presence of D. hongkongensis. Phylogenetic analysis was done using UPGMA and MLM method. Dirofilaria is recognized as a zoonotic entity throughout the world, and dirofilariasis should be considered an emerging zoonosis in southern India. The control of ubiquitous mosquito population is essential to prevent the transmission of microfilaria from animals to arthropods and from arthropods to humans.

Molecular Analysis of Canine Filaria and Its Wolbachia Endosymbionts in Domestic Dogs Collected from Two Animal University Hospitals in Bangkok Metropolitan Region, Thailand

Canine filariasis is caused by several nematode species, such as Dirofilaria immitis, Dirofilaria repens, Brugia pahangi, Brugia malayi, and Acanthocheilonema reconditum. Zoonotic filariasis is one of the world's neglected tropical diseases. Since 2000, the World Health Organization (WHO) has promoted a global filarial eradication program to eliminate filariasis by 2020. Apart from vector control strategies, the infection control of reservoir hosts is necessary for more effective filariasis control. In addition, many studies have reported that Wolbachia is necessary for the development, reproduction, and survival of the filarial nematode. Consequently, the use of antibiotics to kill Wolbachia in nematodes has now become an alternative strategy to control filariasis. Previously, a case of subconjunctival dirofilariasis caused by Dirofilaria spp. has been reported in a woman who resides in the center of Bangkok, Thailand. Therefore, our study aimed to principally demonstrate the presence of filarial nematodes and Wolbachia bacteria in blood collected from domestic dogs from the Bangkok Metropolitan Region, Thailand. A total of 57 blood samples from dogs with suspected dirofilariasis who had visited veterinary clinics in Bangkok were collected. The investigations for the presence of microfilaria were carried out by using both microscopic and molecular examinations. PCR was used as the molecular detection method for the filarial nematodes based on the COI and ITS1 regions. The demonstration of Wolbachia was performed using PCR to amplify the FtsZ gene. All positive samples by PCR were then cloned and sequenced. The results showed that the filarial nematodes were detected in 16 samples (28.07%) using microscopic examinations. The molecular detection of filarial species using COI-PCR revealed that 50 samples (87.72%) were positive; these consisted of 33 (57.89%), 13 (22.81%), and 4 (7.02%) samples for D. immitis, B. pahangi, and B. malayi, respectively. While the ITS1-PCR showed that 41 samples (71.93%) were positive-30 samples (52.63%) were identified as containing D. immitis and 11 samples (19.30%) were identified to have B. pahangi, whereas B. malayi was not detected. Forty-seven samples (82.45%) were positive for Wolbachia DNA and the phylogenetic tree of all positive Wolbachia was classified into the supergroup C clade. This study has established fundamental data on filariasis associated with Wolbachia infection in domestic dogs in the Bangkok Metropolitan Region. An extensive survey of dog blood samples would provide valuable epidemiologic data on potential zoonotic filariasis in Thailand. In addition, this information could be used for the future development of more effective prevention and control strategies for canine filariasis in Thailand.

A preliminary survey of filarial parasites in dogs and cats in Sri Lanka

Human brugian filariasis has re-emerged in Sri Lanka after a quiescent period of four decades. This study investigated the prevalence of canine and feline filarial parasites in three localities with human sub-periodic brugian filariasis, in order to determine their potential reservoir status. All reachable dogs and cats, both stray and domestic, within a 350m radius of an index case of brugian filariasis in three locations (Madampe, Wattala and Weliweriya) were screened for microfilariae using Giemsa stained thick blood smears. A representative sample of canine and feline blood samples positive for Brugia spp. microfilariae by microscopy, from each of the three locations, were further analyzed by PCR with specific primers for internal transcribed spacer region 2 (ITS2) of the ribosomal DNA. A total of 250 dogs and 134 cats were screened. The overall microfilaraemia rates were high among both dogs (68.8%) and cats (47.8%). The prevalence of microfilaraemia was significantly higher among dogs than cats (p<0.05). Two filarial species were identified based on morphology of microfilariae: Dirofilaria (Nochtiella) repens (dogs, 54.4% and cats, 34.3%) and Brugia spp. (dogs, 51.6% and cats, 30.6%). PCR analysis of canine (n = 53) and feline (n = 24) samples elicited bands in the region of 615bp, which confirmed Brugia malayi infection. Co-infection with D.(N.) repens was detected by PCR with an additional band at 484bp, in 36 canine and 17 feline samples. Overall microfilaraemia rates of dogs (81.8%) and cats (75%) in Madampe (rural) were significantly higher than in urbanized Wattala (dogs, 62.4% and cats, 26.0%) (p<0.05). High rates of zoonotic filarial infections strongly implicate dogs and cats as potential reservoirs for human dirofilariasis and brugian filariasis in Sri Lanka.

Prevalence of antibodies against Toxoplasma gondii in pets and their owners in Shandong province, Eastern China

Background

Pet ownership in China has been steadily increasing over recent years. However, the risk of pet-associated zoonotic infection with the protozoan parasite Toxoplasma gondii remains poorly defined.

Methods

In a cross-sectional survey, we have determined the seroprevalence of T. gondii infection in pet dogs and cats, and pet owners. Serum samples were collected from 360 pets and 460 corresponding pet owners between March 2016 to June 2017, from Shandong province, eastern China. Sera from the animals were tested for anti-T. gondii antibodies using an indirect haemagglutination assay (IHA) and from the pet owners using an enzyme-linked immunosorbent assay (ELISA).

Results

Antibodies against T. gondii were detected in 67 of 360 (18.61%) pets. Seroprevalence of T. gondii in pet cats and dogs was 21.67% and 15.56%, respectively. IgG and IgM antibodies were detected in 79 (17.17%) and 4 (0.87%) of pet owners, respectively; with a total of 83 of 460 (18.04%) pet owners testing seropositive for T. gondii. Our seroprevalence data also suggest that cat owners in general and female pet owners in particular could face a higher risk of acquiring T. gondii infection.

Conclusions

Significant levels of anti-T. gondii antibodies were detected in the pets and their owners in Shandong province, eastern China, indicating a potential zoonotic risk. Prophylactic measures should be implemented to reduce the risk of pet owner’s exposure to T. gondii infection.

Gastrointestinal Parasites in Shelter Dogs: Occurrence, Pathology, Treatment and Risk to Shelter Workers

Dogs entering shelters can carry gastrointestinal parasites that may pose serious risks to other animals, shelter staff and visitors. Shelters provide an environment that could facilitate the spread of parasitic infections between animals. Nematodes and protozoa that transmit through ingestion or skin penetration are major enteric parasites of concern in shelter settings. Ancylostoma spp., Uncinaria stenocephala, Toxocara canis, Toxascaris leonina, Trichuris vulpis and Dipylidium caninum are the major helminths while Giardia, Cryptosporidium, Isospora spp. and Sarcocystis spp. are the most prevalent protozoan parasites in shelter dogs. The prevalence of gastrointestinal parasites in shelter dogs is typically higher than in owned dogs. A range of cost-effective drugs is available for prevention and control of helminths in shelters, notably fenbendazole, pyrantel, oxantel, and praziquantel. Parasiticide options for protozoan parasites are often cost-prohibitive or limited by a lack of veterinary registration for use in dogs. Environmental control measures reliant upon hygiene and facility management are therefore a mainstay for control and prevention of protozoan parasites in shelters. This philosophy should also extend to helminth control, as integrated parasite control strategies can allow anthelmintics to be used more sparingly and judiciously. The purpose of this article is to comprehensively review the current knowledge on the prevalence of gastrointestinal parasites most commonly found in dogs in shelters, canvass recommended treatment programs in shelter dogs, and to explore the likelihood that parasiticide resistance might emerge in a shelter environment.

Urban Dog Parks as Sources of Canine Parasites: Contamination Rates and Pet Owner Behaviours in Lisbon, Portugal

Dog parks represent a recent trend in western countries, enabling owners to spend quality time with their pets in a controlled environment. Despite their growing popularity, few studies have been performed to date on these parks to investigate dog intestinal parasitic infections and soil contamination. The present study examined 369 faecal and 18 soil samples collected from 3 dog parks in Greater Lisbon, Portugal. Additionally, 102 interviews were performed with dog owners to assess dog-walking behaviours and parasite risk. In total, 33% of the faecal dog samples were infected with at least one parasitic agent: hookworms (16.5%), Cryptosporidium spp. (11.9%), Giardia spp. (11.4%), Toxascaris leonina (1.1%), Cystoisospora spp. (1.1%), Toxocara spp. (0.5%), and Sarcocystis sp. (0.3%). The soil of all the parks was contaminated with hookworm eggs. This is the first study performed in a European urban area to assess canine faecal contamination and parasitic agents in dog parks. Our results highlight the potential of these parks as a source of transmission for canine parasites, including some with zoonotic potential. Public awareness and effective preventive measures should be promoted to minimise the health-risk impact to both animals and humans, under the scope of environmental and public health.

Morphology of cat vomeronasal organ non-sensory epithelium during postnatal development

The vomeronasal organ has an important role in mammal's social and sexual behaviours. In addition, it mediates defensive behavior through detection of protein pheromone homologues. In this work, a detailed morphological description of the postnatal development of the non-sensory epithelium (NSE) lining the vomeronasal duct (VND) of the female cat is provided using various histological techniques. The study focused on newborn, 2 weeks, 4 weeks, and 8 weeks of postnatal ages using four animals for each age. We report here for the first time that three types of NSE line the rostral segment of the VND; nonkeratinized stratified squamous epithelium, stratified cuboidal epithelium, and ciliated pseudo stratified columnar ciliated epithelium with goblet cells and that the VND undergoes 90° a change in its its axis from the vertical position caudally to the horizontal position rostral. The NSE which lines the lateral side of the VND middle segment is consists of cliated pseudostratified columnar epithelium without goblet cells. In addition to basal cells, the NSE contains ciliated and three types of nonciliated columnar epithelial cells (dark, light, and unstained). Mitotic figures were observed only in the basal cells layer during the first 2 weeks of postnatal development. Intraepithelial invading inflammatory cells were uncommon. Scanning electron microscopy revealed unevenly distributed long cilia intermingled with microvillar processes and intervening short microvillar processes. These projecting cilia and microvilli revealed a gradual increase in their height during development toward maturity.

Prevalence and Risk Factors Associated with Faecal Shedding of Cryptosporidium Oocysts in Dogs in the Federal Capital Territory, Abuja, Nigeria

Cryptosporidium is one of the causes of diarrhoeal illness in man and animals worldwide. The aim of the study was to determine the prevalence and risk factors associated with faecal shedding of Cryptosporidium oocysts in dogs in FCT Abuja, Nigeria. A total of 276 dog faecal samples were examined using Modified Acid Fast (MAF) technique and Enzyme Linked Immunosorbent Assay (ELISA). Fifteen (5.4%) and 51 (18.5%) out of the 276 dog faecal samples examined were positive for Cryptosporidium oocysts and coproantigens, respectively. There was a fair agreement (0.371) between the two tests used in this study. The prevalence of Cryptosporidium infection was highest in 4 dogs (21.0%) between 3 and 9 months of age. Ten diarrhoeic dogs (30.3%) and 31 dogs from rural settlements were more infected (22.46%) with Cryptosporidium oocysts. There was statistical association between prevalence of Cryptosporidium and confinement of dogs (OR = 0.41; 95% CI on OR: 0.21 < OR < 0.80). However, there was no statistical association (P > 0.05) between prevalence of Cryptosporidium and age, diarrhoeic status of the dogs, sex, breed, and location. A total of 62.7% respondents did not have prior knowledge about dogs harbouring organisms that can infect humans. The finding of this research is of public health significance.

Seroprevalence and risk factors of Toxocara infection among children in Shandong and Jilin provinces, China

This cross-sectional study was aimed to investigate the Toxocara serology in children in Shandong and Jilin provinces, China using an enzyme-linked immunosorbent assay (ELISA). The overall Toxocara seroprevalence among the study population (n=1458) was 19.3%, sick children (26.4%) had significantly higher seroprevalence than clinically healthy children (14.4%) (P<0.05), and the highest Toxocara seroprevalence was found in children suffering from chronic cough (40.6%), followed by recurrent abdominal pain (40.0%), recurrent headache (38.1%), slight fever (36.2%), and recurrent vomiting (31.6%). Place of residence, education level, type of school, keeping dogs at home, contact with dogs and cats and exposure with soil were found to be associated with Toxocara infection. Our findings show that children infection with Toxocara is common in Shandong and Jilin provinces, eastern and northeastern China, indicating an immediate need for implementing strategies and measures to prevent and control Toxocara infection in children in China.

Canine filarial infections in a human Brugia malayi endemic area of India

A very high prevalence of microfilaremia of 42.68 per cent out of 164 canine blood samples examined was observed in Cherthala (of Alappuzha district of Kerala state), a known human Brugia malayi endemic area of south India. The species of canine microfilariae were identified as Dirofilaria repens, Brugia malayi, and Acanthocheilonema reconditum. D. repens was the most commonly detected species followed by B. pahangi. D. immitis was not detected in any of the samples examined. Based on molecular techniques, microfilariae with histochemical staining pattern of "local staining at anal pore and diffuse staining at central body" was identified as D. repens in addition to those showing acid phosphatase activity only at the anal pore. Even though B. malayi like acid phosphatase activity was observed in few dogs examined, they were identified as genetically closer to B. pahangi. Hence, the possibility of dogs acting as reservoirs of human B. malayi in this area was ruled out.

Occurrence and molecular characterization of Cryptosporidium in dogs in Henan Province, China

Background

Cryptosporidiosis in dogs has been reported worldwide, involving both asymptomatic and diarrheic dogs. Large-scale surveys of Cryptosporidium infection in dogs have been performed in some countries using differents diagnostic methods. But, few data are available on the infection rate and molecular characteristics of Cryptosporidium spp. in dogs in China.

Result

In this study, 770 fecal samples from 66 locations in Henan Province were examined. The average Cryptosporidium infection rate was 3.8%, with dogs in kennels having the highest rate of 7.0% (χ² = 14.82, P < 0.01). The infection rate was 8.0% in dogs younger than 90 days, which was significantly higher than that in the other age groups (1.1–3.8%;χ² = 18.82, P < 0.01). No association was noted between the infection rate and the sex of the dogs. Twenty-nine Cryptosporidium-positive samples were amplified at the small subunit rRNA (SSU rRNA), 70-kDa heat shock protein (HSP70), and actin loci using PCR. Sequence analysis of these amplicons identified only Cryptosporidium canis, which showed 100% identity with the published sequences of the SSU rRNA, HSP70, and actin genes.

Conclusions

Our results confirm that C. canis is popular in the dog population in China, considering the large number of dogs in China and the close contact between dogs and humans, the role of C. canis in the transmission of human cryptosporidiosis warrants attention.

Serological survey of Ehrlichia species in dogs, horses and humans: zoonotic scenery in a rural settlement from southern Brazil

The aims of this study were to determine the seroprevalence of Ehrlichia spp. and risk factors for exposure in a restricted population of dogs, horses, and humans highly exposed to tick bites in a Brazilian rural settlement using a commercial ELISA rapid test and two indirect immunofluorescent assays (IFA) with E. canis and E. chaffeensis crude antigens. Serum samples from 132 dogs, 16 horses and 100 humans were used. Fifty-six out of 132 (42.4%) dogs were seropositive for E. canis. Dogs > one year were more likely to be seropositive for E. canis than dogs ≤ one year (p = 0.0051). Ten/16 (62.5%) and 8/16 (50%) horses were seropositive by the commercial ELISA and IFA, respectively. Five out of 100 (5%) humans were seropositive for E. canis and E. chaffeensis. Rhipicephalus sanguineus (n = 291, 97.98%) on dogs and Amblyomma cajennense (n = 25, 96.15%) on horses were the most common ticks found. In conclusion, anti-Ehrlichia spp. antibodies were found in horses; however, the lack of a molecular characterization precludes any conclusion regarding the agent involved. Additionally, the higher seroprevalence of E. canis in dogs and the evidence of anti-Ehrlichia spp. antibodies in humans suggest that human cases of ehrlichiosis in Brazil might be caused by E. canis, or other closely related species.

Dogs, cats, parasites, and humans in Brazil: opening the black box

Dogs and cats in Brazil serve as primary hosts for a considerable number of parasites, which may affect their health and wellbeing. These may include endoparasites (e.g., protozoa, cestodes, trematodes, and nematodes) and ectoparasites (i.e., fleas, lice, mites, and ticks). While some dog and cat parasites are highly host-specific (e.g., Aelurostrongylus abstrusus and Felicola subrostratus for cats, and Angiostrongylus vasorum and Trichodectes canis for dogs), others may easily switch to other hosts, including humans. In fact, several dog and cat parasites (e.g., Toxoplasma gondii, Dipylidium caninum, Ancylostoma caninum, Strongyloides stercoralis, and Toxocara canis) are important not only from a veterinary perspective but also from a medical standpoint. In addition, some of them (e.g., Lynxacarus radovskyi on cats and Rangelia vitalii in dogs) are little known to most veterinary practitioners working in Brazil. This article is a compendium on dog and cat parasites in Brazil and a call for a One Health approach towards a better management of some of these parasites, which may potentially affect humans. Practical aspects related to the diagnosis, treatment, and control of parasitic diseases of dogs and cats in Brazil are discussed.

Use of a commercial enzyme-linked immunosorbent assay for rapid detection of Giardia duodenalis in dog stools in the environment

Giardia duodenalis is considered a potentially zoonotic protozoan. Some animal species, including infected dogs, may play an important role in the spread of Giardia cysts through environmental contamination with their feces. In the present study, a commercial enzyme-linked immunosorbent assay (ELISA) was used to examine 143 samples of dog feces collected in urban areas as an indicator of the risk of field contamination. Using a Bayesian statistical approach, the ELISA showed a sensitivity of 88.9% and a specificity of 95.8% with positive and negative predictive values of 89.6% and 95.4%, respectively. The test affords the advantage of rapid processing of fecal samples without a complex technical structure and extensive costly labor. Moreover, the present results show that the assay provides public health veterinarians with a practical tool that can be used in screening programs, as a valid alternative or as an adjunct to other tests, in order to assess the biological risk of exposure to G. duodenalis cysts from dogs in human settlements. However, the test may not be completely accurate for human health risk evaluation, as it does not discriminate between zoonotic and non-zoonotic isolates.

Prevalence of fleas and gastrointestinal parasites in free-roaming cats in central Mexico

The prevalence of fleas and gastrointestinal parasites in free-roaming and domestic cats in central Mexico was evaluated. Three hundred and fifty eight cats captured in the street or brought in by owners to the Animal Control Center Unit, a unit of State Government, from June 2010 to May 2011, were included in the study. All cats were examined for the presence of fleas and gastrointestinal worms. One-hundred and ninety (53%) cats were infested with at least one flea species. Single infestations were observed in 106 (30%) cats and mixed infestations in 84 (23%) cats. Four species of fleas were recovered: Ctenocephalides felis in 53% of the cats, C. canis in 18%, Echidnophaga gallinacea in 7% and Pulex irritans in 1%. One-hundred and sixty three (45%) cats were infected with one or more species of gastrointestinal parasites: 48 (13%) with nematodes, 145 (40%) with cestodes, and one animal presented Moniliformis moniliformis. Prevalences and mean intensity of infection were: Physaloptera praeputialis 7 and 18; T. cati 3 and 2; Ancylostoma tubaeforme 2.5 and 2; Toxascaris leonina 0.5 and 2; Dipylidium caninum 36 and 32; Taenia taeniformis 4 and 3 and Moniliformis moniliformis 0.3 and 106, respectively. There was significant association (P<0.01), between season and ectoparasites load, more fleas were obtained in the summer and autumn than in the winter and spring; however, no statistical difference was observed for endoparasites load (P>0.05). The correlation between the total number of ectoparasites and endoparasites was not significant (r = 0.089, P = 0.094).

Pet roundworms and hookworms: a continuing need for global worming

Ascarids and ancylostomatids are the most important parasites affecting dogs and cats worldwide, in terms of diffusion and risk for animal and human health. Different misconceptions have led the general public and pet owners to minimize the importance of these intestinal worms. A low grade of interest is also registered among veterinary professions, although there is a significant merit in keeping our guard up against these parasites. This article reviews current knowledge of ascarids and ancylostomatids, with a special focus on pathogenicity, epidemiology and control methods in veterinary and human medicine.

Canine vector-borne diseases in India: a review of the literature and identification of existing knowledge gaps

Despite the combination of favourable climate for parasites and vectors, and large populations of stray dogs, information concerning the epidemiology, diagnosis and management of canine vector-borne diseases in India is limited. However, with the country's expanding economy and adaptation to western culture, higher expectations and demands are being placed on veterinary surgeons for improved knowledge of diseases and control. This review aims to provide an overview of the current state of knowledge of these diseases in India and identify existing knowledge gaps in the literature which need to be addressed. The available literature on this subject, although limited, suggests that a number of canine vector-borne diseases such as filariasis, babesiosis and ehrlichiosis are endemic throughout India, as diagnosed mostly by morphological methods. Detailed investigations of the epidemiology and zoonotic potential of these pathogens has been neglected. Further study is essential to develop a better understanding of the diversity of canine vector-borne diseases in India, and their significance for veterinary and public health.

Cryptosporidium and cryptosporidiosis

Cryptosporidium is one of the most common enteric protozoan parasites of vertebrates with a wide host range that includes humans and domestic animals. It is a significant cause of diarrhoeal disease and an ubiquitous contaminant of water which serves as an excellent vehicle for transmission. A better understanding of the development and life cycle of Cryptosporidium, and new insights into its phylogenetic relationships, have illustrated the need to re-evaluate many aspects of the biology of Cryptosporidium. This has been reinforced by information obtained from the recent successful Cryptosporidium genome sequencing project, which has emphasised the uniqueness of this organism in terms of its parasite life style and evolutionary biology. This chapter provides an up to date review of the biology, biochemistry and host parasite relationships of Cryptosporidium.

The prevalence and intensity of gastrointestinal parasites of dogs in Ile-Ife, Nigeria

A study of gastrointestinal parasites in 269 faecal samples from dogs (Canis familiaris) collected from Ile-Ife, Nigeria between January and December 2004, revealed seven helminth species:Toxocara canis33.8%,Ancylostomasp. 34.6%,Toxascaris leonina3.3%,Trichuris vulpis3.7%,Dipylidium caninum4.1%,Uncinaria stenocephala0.7% andTaeniasp. 1.1%. The faecal egg intensities, determined as mean eggs per gram of faeces ( ± SEM) were:T. canis393.8 ± 83.4,Ancylostomasp. 101.5 ± 32.8,T. leonina14.3 ± 7.9,T. vulpis3.4 ± 1.5,D. caninum2.2 ± 0.8,U. stenocephala0.2 ± 0.2. The prevalence of intestinal parasites was significantly higher (P < 0.05) in dogs of age 0–6 months than in older age groups. There was no significance difference in overall prevalence of intestinal helminth parasites between male (58.3%) and female (50.0%) dogs (P>0.05). The prevalence of helminth parasites was significantly higher (P < 0.05) in free-ranging than in kennelled dogs. The prevalence of helminth parasites was also significantly higher (P < 0.05) in African shepherds than in Alsatians and other exotic breeds. Each helminth parasite had similar prevalences and intensities among both genders (P>0.05) except inT. vulpis. The overall prevalence of intestinal parasites may continue to rise due to lack of functional veterinary clinics for dog care in Ile-Ife. Therefore, there is the need to establish a veterinary facility in Ile-Ife.

Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners

Background

Dogs are the most common pet animals worldwide. They may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. In Nigeria, epidemiological knowledge on these parasites is limited.

Methods

In a community-based study, we examined 396 dogs in urban and rural areas of Ilorin (Kwara State, Central Nigeria) for ectoparasites and intestinal helminths. In addition, a questionnaire regarding knowledge and practices was applied to pet owners.

Results

Nine ectoparasite species belonging to four taxa and six intestinal helminth species were identified: fleas (Ctenocephalides canis, Pulex irritans, Tunga penetrans), mites (Demodex canis, Otodectes sp., Sarcoptes scabiei var. canis), ticks (Rhipicephalus sanguineus, Ixodes sp.), and lice (Trichodectes canis); and Toxocara canis, Ancylostoma sp., Trichuris vulpis, Dipylidium caninum, Taenidae and Strongyloides sp. Overall prevalence of ectoparasites was 60.4% and of intestinal helminths 68.4%. The occurrence of C. canis, R. sanguineus, T. canis, Ancylostoma sp. and T. vulpis was most common (prevalence 14.4% to 41.7%). Prevalence patterns in helminths were age-dependent, with T. canis showing a decreasing prevalence with age of host, and a reverse trend in other parasite species. Knowledge regarding zoonoses was very limited and the diseases not considered a major health problem. Treatment with antiparasitic drugs was more frequent in urban areas.

Conclusion

Parasites of importance for human health were highly prevalent in Nigerian dogs. Interventions should include health education provided to dog owners and the establishment of a program focusing on zoonotic diseases.

Canine vector-borne diseases in Brazil

Canine vector-borne diseases (CVBDs) are highly prevalent in Brazil and represent a challenge to veterinarians and public health workers, since some diseases are of great zoonotic potential. Dogs are affected by many protozoa (e.g., Babesia vogeli, Leishmania infantum, and Trypanosoma cruzi), bacteria (e.g., Anaplasma platys and Ehrlichia canis), and helminths (e.g., Dirofilaria immitis and Dipylidium caninum) that are transmitted by a diverse range of arthropod vectors, including ticks, fleas, lice, triatomines, mosquitoes, tabanids, and phlebotomine sand flies. This article focuses on several aspects (etiology, transmission, distribution, prevalence, risk factors, diagnosis, control, prevention, and public health significance) of CVBDs in Brazil and discusses research gaps to be addressed in future studies.

A longitudinal study on the occurrence of Cryptosporidium and Giardia in dogs during their first year of life

Background

The primary aim of this study was to obtain more knowledge about the occurrence of Cryptosporidium and Giardia in young dogs in Norway.

The occurrence of these parasites was investigated in a longitudinal study by repeated faecal sampling of dogs between 1 and 12 months of age (litter samples and individual samples). The dogs were privately owned and from four large breeds. Individual faecal samples were collected from 290 dogs from 57 litters when the dogs were approximately 3, 4, 6, and 12 months old. In addition, pooled samples were collected from 43 of the litters, and from 42 of the mother bitches, when the puppies were approximately 1 and/or 2 months old.

Methods

The samples were purified by sucrose gradient flotation concentration and examined by immunofluorescent staining.

Results

128 (44.1%) of the young dogs had one or more Cryptosporidium positive samples, whilst 60 (20.7%) dogs had one or more Giardia positive samples. The prevalence of the parasites varied with age. For Cryptosporidium, the individual prevalence was between 5.1% and 22.5%, with the highest level in dogs < 6 months old, and declining with age. For Giardia, the individual prevalence was between 6.0% and 11.4%, with the highest level in dogs > 6 months old, but the differences between age groups were not statistically significant. Significant differences in prevalences were found in relation to geographic location of the dogs. Both parasites occurred at low prevalences in Northern Norway.

Conclusion

Both Cryptosporidium and Giardia are common in Norwegian dogs, with Cryptosporidium more prevalent than Giardia. Prevalences of the parasites were found to be influenced by age, geographical location, and infection status before weaning.

Prevalence ofCampylobacterand four endoparasites in dog populations associated with Hearing Dogs

OBJECTIVES

This study established the prevalence of four gastrointestinal parasites (Isopora species, Giardia species, Uncinaria stenocephala, Toxocara canis) and one bacterial infection (Campylobacter jejuni/coli) in dogs associated with the charity Hearing Dogs for Deaf People.

METHODS

Dogs' faeces were routinely sampled from dogs according to whether they were in Socialising, Kennelling or Visiting the Hearing Dogs site. A further group consisted of dogs with diarrhoea.

RESULTS

Prevalence rates for dogs in Socialising (n=326), Kennelling (n=117), Visiting (n=106) and Diarrhoea (n=59) groups, respectively, were as follows: Campylobacter- 26, 21, 15 and 31 per cent; Coccidia - 3, 0, 0 and 2 per cent; Giardia- 13, 3, 2 and 10 per cent; hookworm - 1, 1, 4 and 5 per cent; and Toxocara- 4, 2, 3 and 2 per cent. There were significant differences in the levels of Giardia and hookworm found between the four different groups of dogs. No significant gender differences were found, and dogs that were positive for Campylobacter in the Visiting group were significantly younger.

CLINICAL SIGNIFICANCE

This study provides current information on the infection rates in specific dog populations in the UK. This is relevant to the veterinary health of dogs and the possible risk of zoonotic infection to humans.

Epidemiological Study of Non-systemic Parasitism in Dogs in Southeast Mediterranean Spain Assessed by Coprological and Post-mortem Examination

The prevalence and risk factors of non-systemic canine ecto- and endoparasitism and anthelminthic use in Murcia located at the centre of the Spanish Mediterranean coastal arch, was investigated by coprology and necropsy in up to 275 pet, city shelter and stray dogs in 2001-2004. Faecal parasite stages were detected in 25% of dogs. Species frequency was 6-10% for Toxocara canis, Ancylostomatidae spp., Toxascaris leonina and Isospora canis, and 0.4-1% for Trichuris vulpis, Giardia lamblia, and Dipylidium caninum. Logistic regression indicated that the risk of intestinal parasitism was highest for dogs <or=1 year old, in the middle to low weight range and kept at the city shelter. Although risk factors varied according to the species, T. canis was most common in <1 year old and Ancylostomatidae spp. was more prevalent in older dogs. This suggests that the dominant species was Uncinaria spp. and not the more zoonotically important Ancylostoma spp. This was further supported by necropsy findings; however, the degree of agreement between post-mortem and coprological examination for intestinal parasites was generally poor. Necropsy revealed 10%G. lamblia, 12%Taenia spp. 38%D. caninum infections. Fleas, ticks and lice were also found in 38%, 6% and 2% of necropsied stray dogs. These results demonstrate the need for an urgent parasite control programme at the city dog shelter and the need to improve the owner's education on zoonotic risks, the proper use of anthelminthics, and other parasite control practices.

ZOONOSES CAUSADAS POR PARASITAS INTESTINAIS DE CÃES E O PROBLEMA DO DIAGNÓSTICO

RESUMO Os últimos 20 anos foram marcados por um intenso progresso tecnológico e por importantes alterações culturais e sociais com reflexos tanto em saúde humana como animal. Entretanto, infelizmente, as zoonoses causadas por parasitas intestinais de cães não deixaram de ser um problema permanente de saúde pública nos países em desenvolvimento, e uma preocupação crescente nos países desenvolvidos. A eficácia e segurança dos novos produtos disponíveis para a prevenção e controle não impediram que enfermidades parasitárias emergissem como um sério problema em animais de companhia. Nesta revisão, foram consideradas as principais espécies de parasitas intestinais de cães, responsáveis por zoonoses, e os aspectos relativos ao diagnóstico coproparasitológico com o objetivo de contribuir para um maior comprometimento dos médicos veterinários no importante papel de agentes promotores de saúde pública e de difusores do conhecimento.

The veterinary and public health significance of hookworm in dogs and cats in Australia and the status of A. ceylanicum

There is no current information regarding the prevalence of hookworm in Australian dogs and cats and based on the results of studies conducted over 20 years ago, where high prevalences of helminths were recorded, the prophylactic administration of broad spectrum anthelmintics has been advocated. During this study, faecal samples were collected from dogs (n=1391) and cats (n=1027) across Australia. Samples were examined by microscopy and information regarding the demographics of each animal, and the management practices they experienced were recorded. A highly sensitive and species-specific PCR-RFLP technique was utilized to differentiate the various hookworm species which can infect dogs and cats directly from eggs in faeces. The prevalence of hookworm in dogs and cats was found to be 6.9% and 1.4%, respectively. Ancylostoma ceylanicum was detected for the first time in Australia in 10.9% of the dogs found positive for hookworm. Significantly, A. ceylanicum is capable of causing a patent infection in humans. After adjusting for other factors with multiple logistic regression, dogs from refuges, dogs originating from a tropical climatic zone, dogs aged 1 year or less, and those dogs which had not received anthelmintics were significantly more likely to be parasitized. Only univariate analysis was conducted for the cats as there were too few samples positive for hookworm. Cats were more likely to be infected with hookworm if they were from refuges, originated from a tropical climatic zone, and had not received treatment with anthelmintics. The results of this study demonstrates the importance of having current information regarding the prevalence of parasites of dogs and cats and the risk factors associated with infection, as well as the need to reassess the veterinary and public health concerns regarding hookworm infection and its control, which are currently based on out-dated information.

An epidemiological study of gastrointestinal parasites of dogs from Southern Greater Buenos Aires (Argentina): age, gender, breed, mixed infections, and seasonal and spatial patterns

A total of 2193 fecal samples from owned dogs were collected during the 2003-2004 period in Southern Greater Buenos Aires, and were evaluated for the presence of intestinal parasites by a flotation-centrifugation method. The overall prevalence was 52.4%, and the 11 species found were: Ancylostoma caninum (13%), Isospora ohioensis complex (12%), Toxocara canis (11%), Trichuris vulpis (10%), Sarcocystis sp. (10%), Giardia duodenalis (9%), Isospora canis (3%), Hammondia-Neospora complex (3%), Dipilydium caninum (18 cases), Cryptosporidium sp. (5 cases), and Toxascaris leonina (1 case). There was no significant difference in the overall prevalence between genders (female = 50.4%, male = 54.6%), and breeds (pure = 52.3%, mixed = 53%), but prevalence in puppies (<1 year) was higher than in adult dogs (62.7% versus 40.8%, respectively). Only the prevalence of A. caninum differed between genders, with higher values for males. The prevalences of six of the parasite species showed a decreasing trend with increasing host age, and an inverse pattern was found for two other species. The prevalences of three protozoa were significantly higher in pure-breed dogs, and those of two nematodes were significantly higher in mixed-breed dogs. The prevalences of T. canis, A. caninum, and T. vulpis were spatially heterogeneous with a clear Southwest-Northeast gradient. Only prevalences of Sarcocystis sp. and G. duodenalis showed seasonal variation. The frequency distribution of the number of species per fecal sample did not differ from a random distribution. Results obtained throughout the world were discussed.

Comparison between natural infection by Cryptosporidium sp., Giardia sp. in dogs in two living situations in the West Zone of the municipality of Rio de Janeiro

In order to compare natural infection by Cyptosporidium sp. and Giardia sp. in clinically healthy dogs living in two situations (animal shelter and household pets), we conducted 166 faecal exams using the technique of centrifugation-flotation in a sugar-saturated solution. Of the faecal samples, 94 came from shelter dogs and 72 from house pets. Eighty-two (49.4%) contained parasite eggs, cysts or oocysts. Of these, four (2.41%) contained Cryptosporidium sp. oocysts and 52 (31.33%) contained Giardia sp. cysts. There was no statistically significant difference between the origin of the dogs and Cryptosporidium sp. infection. Infection by Cryptosporidium sp. was not associated with the living conditions and sex. With respect to Giardia sp., we observed a statistically significant difference (p < 0.001) between the shelter dogs (45%) and the household pets 12.3%. There was no association of infection by Giardia sp. with age or sex.

A review of the biology and epidemiology of cryptosporidiosis in humans and animals

The epidemiology of cryptosporidiosis, an infection caused by several genotypically and phenotypically diverse Cryptosporidium species, has been dynamically changing over the past decade from that of a rare, largely asymptomatic infection to an acute enteric disease of animals and humans. In this review, the current understanding of factors (biology and epidemiology) contributing to the emergence of cryptosporidiosis in animals, including parasite biology, genetic diversity, environmental spread, livestock production trends, presence of the parasite in livestock and companion animals, and potential risk of transmission from animals to humans is highlighted. Potential control measures and the role of veterinary and medical professionals in the prevention of cryptosporidiosis are also discussed.

Discrimination of all genotypes of Giardia duodenalis at the glutamate dehydrogenase locus using PCR-RFLP

A PCR-RFLP genotyping tool was developed and used to characterise morphologically identical isolates of Giardia duodenalis from a variety of host species. Primers were designed to amplify a 432bp region of the glutamate dehydrogenase gene (gdh) from genetic Assemblages AI, AII, BIII, BIV, C, D and E of G. duodenalis. DNA extracted from cultured Giardia trophozoites, Giardia cysts purified from faeces and directly from whole faeces was amplified and sequenced at the gdh and 18SrDNA loci. The gdh sequences were identical with published gdh sequences for each assemblage with a few exceptions. However, in some cases genotyping results obtained using gdh differed from 18SrDNA genotyping results. From gdh sequence information a PCR-RFLP profile was identified for each of the genetic assemblages. PCR-RFLP is a reproducible, reliable and sensitive method for genotyping Giardia. Eight human, 12 cat, 9 dog and 16 cattle faecal isolates were genotyped using PCR-RFLP. This method allows G. duodenalis isolates from human-beings, their companion animals and livestock to be genotyped directly from faeces, leading to valuable information about Giardia genotypes in population without the need for in vitro/in vivo amplification.

Prevalence of dogs with intestinal parasites in Tochigi, Japan in 1979, 1991 and 2002

A total of 772 canine fecal specimens were collected in Tochigi in 1979, 1991 and 2001. The frequency of dogs that were kept indoor in 2002 (72.8%) was significantly higher than that for 1979 (21.2%, P < 0.001) and 1991 (40.6%, P < 0.01). The frequency of parasitized dogs in 2002 (18.8%) was significantly lower than that for 1979 (41.9%, P < 0.01). The findings of this study confirm the declining trend in Japan in the prevalence of helminth parasites in dogs, particularly Ancylostoma caninum and Trichuris vulpis. The reduction in the frequency of dogs with helminths may be mainly a result of the improvement in the environment and the routine use of filaricides.

Cat or dog ownership and seroprevalence of ehrlichiosis, Q fever, and cat-scratch disease

Concerns have been raised about the role of domestic cats or dogs in the acquisition of zoonoses, in particular in pregnant women or immune-suppressed persons. We report that cat or dog ownership is not associated with an increased seroprevalence of antibodies to Anaplasma phagozytophilum, Coxiella burnetii, and Bartonella henselae in symptom-free persons in Styria, Austria.

Development of antiparasitic drugs in the 21st century

Prospects for discovering new antiparasitic drugs for veterinary medicine in the coming century will be determined by economic, social and scientific factors. Consolidation in the pharmaceutical industry in general, and the animal health industry in particular, changes the business conditions in which drug discovery for veterinary medicine occurs. Social pressures on traditional animal agriculture and companion animal ownership have shifted the interest of animal companies primarily to pet medicine. Antiparasitic drug discovery is more than ever targeted to the most lucrative market segments, but the excellence of available drugs, and the apparent lack of resistance in important parasites, reduces industrial motivation to invest in parasitology. Veterinary parasitologists in academia will still have the chance to interact with their industrial counterparts in the traditional ways of supporting drug discovery and development. Nonetheless, there are many new opportunities to expand the research horizons of veterinary parasitology to strengthen the case for retaining a significant presence in the animal health industry.