Epidemiology Of Parasites Research Articles

Epidemiology of bovine hemoprotozoa parasites in cattle and water buffalo in Vietnam.

A PCR-based survey of hemoprotozoa parasites detected Babesia bigemina, Theileria orientalis and Trypanosoma theileri among cattle and water buffalo in Vietnam, and a new Babesia sp. closely related to Babesia ovata was detected in cattle only. In addition, Theileria annulata and Trypanosoma evansi were not detected in both cattle and water buffalo. Phylogenetic analysis detected T. orientalis MPSP genotypes 3, 5, 7 and N3 in cattle and 5, 7, N1 and N2 in water buffalo. Additionally, water buffalo-derived T. theileri CATL sequences clustered together with a previously reported cattle-derived sequence from Vietnam. This is the first report of a new Babesia sp. in cattle, and T. orientalis MPSP genotype 7 and T. theileri in water buffalo in Vietnam.

Knowledge gaps in the epidemiology of Toxocara: the enigma remains.

Toxocara species infect a wide range of companion, domestic and wild animals as definitive and paratenic hosts, via multiple routes of transmission, producing long-lived tissue-inhabiting larvae and resistant eggs that can survive in the external environment. Therefore Toxocara and the disease it causes in humans, toxocariasis, represents an ideal aetiological agent for the development of the one health approach. However, despite increasing awareness of the public health significance of toxocariasis, gaps in our understanding of certain key aspects of the parasite's biology and epidemiology remain. These gaps hinder our ability to integrate research effort within the veterinary, medical and environmental disciplines. This review will highlight key deficits in our understanding of nine dimensions of Toxocara epidemiology and discuss a potential scenario to develop a more integrated, one health approach to improve our understanding of the prevention and control of this complex and cryptic zoonosis.

Exploring the Gastrointestinal "Nemabiome": Deep Amplicon Sequencing to Quantify the Species Composition of Parasitic Nematode Communities.

Parasitic helminth infections have a considerable impact on global human health as well as animal welfare and production. Although co-infection with multiple parasite species within a host is common, there is a dearth of tools with which to study the composition of these complex parasite communities. Helminth species vary in their pathogenicity, epidemiology and drug sensitivity and the interactions that occur between co-infecting species and their hosts are poorly understood. We describe the first application of deep amplicon sequencing to study parasitic nematode communities as well as introduce the concept of the gastro-intestinal “nemabiome”. The approach is analogous to 16S rDNA deep sequencing used to explore microbial communities, but utilizes the nematode ITS-2 rDNA locus instead. Gastro-intestinal parasites of cattle were used to develop the concept, as this host has many well-defined gastro-intestinal nematode species that commonly occur as complex co-infections. Further, the availability of pure mono-parasite populations from experimentally infected cattle allowed us to prepare mock parasite communities to determine, and correct for, species representation biases in the sequence data. We demonstrate that, once these biases have been corrected, accurate relative quantitation of gastro-intestinal parasitic nematode communities in cattle fecal samples can be achieved. We have validated the accuracy of the method applied to field-samples by comparing the results of detailed morphological examination of L3 larvae populations with those of the sequencing assay. The results illustrate the insights that can be gained into the species composition of parasite communities, using grazing cattle in the mid-west USA as an example. However, both the technical approach and the concept of the ‘nemabiome’ have a wide range of potential applications in human and veterinary medicine. These include investigations of host-parasite and parasite-parasite interactions during co-infection, parasite epidemiology, parasite ecology and the response of parasite populations to both drug treatments and control programs.

Absence of population genetic structure in Heterakis gallinarum of chicken from Sichuan, inferred from mitochondrial cytochrome c oxidase subunit I gene

Population genetics information provides a foundation for understanding the transmission and epidemiology of parasite and, therefore, may be used to assist in the control of parasitosis. However, limited available sequence information in Heterakis gallinarum has greatly impeded the study in this area. In this study, we first investigated the genetic variability and genetic structure of H. gallinarum. The 1325 bp fragments of the mitochondrial COX1 gene were amplified in 56 isolates of H. gallinarum from seven different geographical regions in Sichuan province, China. The 56 sequences were classified into 22 haplotypes (H1–H22). The values of haplotype diversity (0.712) and nucleotide diversity (0.00158) in Sichuan population indicate a rapid expansion occurred from a relatively small, short-term effective population in the past. The haplotype network formed a distribution around H1 in a star-like topology, and the haplotypes did not cluster according to their geographical location. Similar conclusions could be made from MP phylogenetic tree. The Fst value (Fst<0.16965) and AMOVA analysis revealed that no significant genetic differentiation was observed among the seven different geographical populations. Neutrality tests (Tajima's D and Fu’s Fs) and mismatch analysis indicated that H. gallinarum experienced a population expansion in the past. Our results indicated that H. gallinarum experienced a rapid population expansion in the past, and there was a low genetic diversity and an absence of population structure across the population.

Where's the risk? Landscape epidemiology of gastrointestinal parasitism in Alberta beef cattle.

BackgroundGastrointenstinal nematodes (GIN) present a serious challenge to the health and productivity of grazing stock around the globe. However, the epidemiology of GIN transmission remains poorly understood in northern climates. Combining use of serological diagnostics, GIS mapping technology, and geospatial statistics, we evaluated ecological covariates of spatial and temporal variability in GIN transmission among bovine calves pastured in Alberta, Canada.MethodsSera were collected from 1000 beef calves across Alberta, Canada over three consecutive years (2008–2010) and analyzed for presence of anti-GIN antibodies using the SVANOVIR Ostertagia osteragi-Ab ELISA kit. Using a GIS and Bayesian multivariate spatial statistics, we evaluated the degree to which variation in specific environmental covariates (e.g. moisture, humidity, temperature) was associated with variation in spatial and temporal heterogeneity in exposure to GIN (Nematodirus and other trichostrongyles, primarily Ostertagia and Cooperia).ResultsVariation in growing degree days above a base temperature of 5 °C, humidity, air temperature, and accumulated precipitation were found to be significant predictors of broad–scale spatial and temporal variation in serum antibody concentrations. Risk model projections identified that while transmission in cattle from southeastern and northwestern Alberta was relatively low in all years, rate of GIN transmission was generally higher in the central region of Alberta.ConclusionsThe spatial variability in risk is attributed to higher average humidity, precipitation and moderate temperatures in the central region of Alberta in comparison with the hot, dry southeastern corner of the province and the cool, dry northwestern corner. Although more targeted sampling is needed to improve model accuracy, our projections represent an important step towards tying treatment recommendations to actual risk of infection.

Dynamics of epidemiological intelligence for exploitation in effective worm management in sheep - A Rajasthan experience

Being of ubiquitous nature and omnipresence of the gastrointestinal (GI) parasites, their management presents a difficult challenge following wide-spread emergence of anthelmintic resistance. Anthelmintics have a definite role to play in worm management but their frequency of use should be minimised to the extent possible and the available resources of anthelmintics could be used judiciously by exploiting the knowledge of parasite epidemiology. The present communication discusses different aspects of worm biology and their interaction with environment, host and managemental practices. The bioclimatographs suggested existence of suitable conditions for translation of exogenous stages of Haemonchus contortus from late May to late September in semi-arid region and from mid June to late August / September in arid region. Based on real-time observations, different strategies were developed and tested for efficient management of GI nematodes in sheep flocks of Rajasthan. The agro-climatic conditions and lambing pattern do not favour the development of strongyle larvae during December-June, resulting in absence of typical peri-parturient rise in faecal egg counts (FECs). However, the epidemiology of strongyle worms showed the possibility of hypobiosis. An initial rising trend in FECs in June could be probably due to resumption of development of hypobiotic worms within the host, giving peak of infection in July and providing the source of pasture contamination during monsoon. The decline in FECs in the following months may be due to spontaneous occurrence of “self-cure” phenomenon. The GI parasite populations in small ruminants are highly aggregated and over-dispersed, with around 80% of the worms found in only 20-30% of the host. Thus, requirement for treatment is a reflection of the genetic basis of host variation in either innate or acquired resistance to parasites or resilience. The over-dispersion phenomenon was used in the form of targeted selective treatment and for breeding for resistance / resilience to parasites ultimately with the aim to increase the size of refugia, maintain anthelmintic efficacy and cost-effective worm management.

Risk Factors Associated with the Presence of Parasitic Diseases in Cultured Tench (Tinca tinca L.) from the Tormes River (NW Spain)

The present study aims to assess the epidemiology of fish parasites in culturedfish populations. This study was carried out during a three year period (20052007) at a tench (Tinca tinca L.) fish farm located in the Northwestern region of Spain. 114 fish as well as 14 physicochemical and microbiological water parameters were analyzed in order to determine the main impact of both the host and the environmental parameters on the presence and the abundance of parasites in their host (host-parasite relation).Four different parasites, namely Ichthyophthirius multifiliis, Tripartiella sp., Myxobolus sp. and Gyrodactylus sp., were isolated, being the ciliates, with up to 100% of prevalence, the most abundant, with only 5.56% and 2.63% of the fish infected by the myxozoan and the monogenean, respectively. With the exception of the high alkalinity registered at the fish farm (pH > 9.0), the rest of the values fell within the recommended water quality parameters for cyprinids. The statistical and epidemiological analysis revealed that size, somatic condition and sex (intrinsic parameters) in addition to several environmental factors, linked to seasonality and poor water quality, have significant effect on the host-parasite relationship, increasing the likelihood of the parasite presence (p<0.050). We conclude that, in temperate climates, the development, reproduction and transmission of the parasites are triggered under the most stable conditions of the ecosystem (hydrological, physicochemical and biological) i.e. the warmer periods of the year, when the cyprinid populations display a more active and gregarious behavior. The results of the present study will also help understanding both the epidemiology and the parasitology of fresh water cultured-fish, and, what is more important, will help designing management strategies and procedures for preventing parasitic

The role of wild canids and felids in spreading parasites to dogs and cats in Europe: Part I: Protozoa and tick-borne agents

Over the last few decades, the world has witnessed radical changes in climate, landscape, and ecosystems. These events, together with other factors such as increasing illegal wildlife trade and changing human behaviour towards wildlife, are resulting into thinning boundaries between wild canids and felids and their domestic counterparts. As a consequence, the epidemiology of diseases caused by a number of infectious agents is undergoing profound readjustements, as pathogens adapt to new hosts and environments. Therefore, there is a risk for diseases of wildlife to spread to domestic carnivores and vice versa, and for zoonotic agents to emerge or re-emerge in human populations. Hence, the identification of the hazards arising from the co-habitation of these species is critical in order to plan and develop adequate control strategies against these pathogens. In the first of this two-part article, we review the role that wild canids and felids may play in the transmission of protozoa and arthropod-borne agents to dogs and cats in Europe, and provide an account of how current and future progress in our understanding of the ecology and epidemiology of parasites, as well as of host-parasite interactions, can assist efforts aimed at controlling parasite transmission.

Epidemiological survey of Angiostrongylus vasorum in dogs and slugs around a new endemic focus in Scotland

The nematode parasite Angiostrongylus vasorum is an increasingly important cause of respiratory and other diseases in dogs. Geographical spread from previously limited endemic foci has occurred rapidly. This paper investigates...

Slaughterhouse survey of cystic echinococcosis in cattle and sheep from the Republic of Moldova.

The Echinococcus granulosus tapeworm is responsible for cystic echinococcosis (CE), a zoonotic disease with worldwide distribution. The life cycle of the parasite is mainly domestic and takes place between dogs and livestock species. A slaughterhouse survey was conducted in 2012 in the Republic of Moldova in order to estimate the prevalence of CE. A total of 1525 cattle, 5580 sheep and 12,700 pigs were surveyed. No CE infection was observed in pigs, while prevalence was estimated at 59.3% in cattle and 61.9% in sheep. Infection was significantly higher in animals raised in private households than in those from collective farms. The frequency of infection increased with age in both species. In cattle and in sheep, infection of both the liver and lungs was the most common, while infection in the lungs only was much less frequent. Farm type appears to be an important factor in CE infection in Moldova, due to the extensive farming and the home-slaughtering undertaken in the majority private sector, despite a high prevalence of CE also recorded in the public sector. The low fertility of cysts in cattle (1.1%) compared to sheep (47.6%) confirmed the maintenance of E. granulosus sensu stricto in a dog-sheep life cycle which excludes cattle. Further studies are needed to obtain a complete overview of the parasite's epidemiology in its intermediate and definitive hosts, in order to implement control and preventive measures, with specific attention given to farms in the private sector.

The distinctive features of Indian malaria parasites

Malaria and factors driving malaria are heterogeneous in India, unlike in other countries, and the epidemiology of malaria therefore is considered 'highly complex'. This complexity is primarily attributed to several unique features of the malaria parasites, mosquito vectors, malaria-susceptible populations, and ecoclimatic variables in India. Recent research on the genetic epidemiology of Indian malaria parasites has been successful in partly unraveling the mysteries underlying these complexities.

Epidemiology of ovine gastrointestinal parasites under different worm management strategies at an organized farm in arid Rajasthan

During the period from 2001 to 2014, a total of 24754 faecal samples were evaluated to assess the epidemiological profile of gastrointestinal (GI) parasites and performance of sheep under three different worm management strategies (conventional, modified and targeted selective) at the Sheep Breeding Farm, Fatehpur in arid Rajasthan. The climatic observations showed existence of suitable period for translation of exogenous stages of Haemonchus contortus and Trichstrongylus spp from mid-June to early October and from late October to early March, respectively. The overall incidence of strongyle worms (dominated by H. contortus) ranged from 51.1 (modified treatment) to 66.5% (conventional treatment) (P<0.001) and varied among months in all the three strategies. The incidence of other GI parasites viz., Trichuris spp, Strongyloides papillosus and Moneizia spp was very low while, incidence of Eimeria spp was moderate (27.7%). The monthly intensity of strongyle infection varied significantly (P<0.001) in all the treatment strategies and a peak was observed in October, August and August-September in conventional, modified and targeted selective treatment schemes, respectively. The mean herbage larval count varied significantly (P<0.001) from 32.7±22.1 (March) to 858.2±291.7 L3/kg dry matter of herbage (September). It was found that use of minimum anthelmintic intervention through modified or targeted selective treatment approach in farm flocks had no adverse effect on flock productivity and performance. It was concluded that conventional approach was not based on parasite epidemiology and there is no merit in adopting the conventional strategy in preference to the modified or targeted selective treatment strategy. The latter two strategies were more rewarding and provided better opportunities for gainful interaction between epidemiology, weather and management of flocks, reduced anthelmintic drench frequency, better rotational use of anthelmintic types, reduced selection pressure in parasite population and unwanted expenditure incurred on anthelmintics.

Epidemiology of gastrointestinal nematodosis in goats maintained at farm and field conditions in chhattisgarh plain

Studies were conducted to understand nematode parasite epidemiology in goats maintained under field and farm condition at Durg situated in the agroclimatic zone of Chhattisgarh Plain by monitoring monthly faecal egg counts and genera of parasites present for a period of one year. While increased egg counts in goats were observed during July to September in goats of both field and farm conditions, the egg counts were significantly (P<0.05) higher in field goats with dominance of haematophagous nematode Haemonchus spp.

Global phylogeography of the avian malaria pathogen Plasmodium relictum based on MSP1 allelic diversity

Knowing the genetic variation that occurs in pathogen populations and how it is distributed across geographical areas is essential to understand parasite epidemiology, local patterns of virulence, and evolution of host‐resistance. In addition, it is important to identify populations of pathogens that are evolutionarily independent and thus ‘free’ to adapt to hosts and environments. Here, we investigated genetic variation in the globally distributed, highly invasive avian malaria parasite Plasmodium relictum, which has several distinctive mitochondrial haplotyps (cyt b lineages, SGS1, GRW11 and GRW4). The phylogeography of P. relictum was accessed using the highly variable nuclear gene merozoite surface protein 1 (MSP1), a gene linked to the invasion biology of the parasite. We show that the lineage GRW4 is evolutionarily independent of GRW11 and SGS1 whereas GRW11 and SGS1 share MSP1 alleles and thus suggesting the presence of two distinct species (GRW4 versus SGS1 and GRW11). Further, there were significant differences in the global distribution of MSP1 alleles with differences between GRW4 alleles in the New and the Old World. For SGS1, a lineage formerly believed to have both tropical and temperate transmission, there were clear differences in MSP1 alleles transmitted in tropical Africa compared to the temperate regions of Europe and Asia. Further, we highlight the occurrence of multiple MSP1 alleles in GRW4 isolates from the Hawaiian Islands, where the parasite has contributed to declines and extinctions of endemic forest birds since it was introduced. This study stresses the importance of multiple independent loci for understanding patterns of transmission and evolutionary independence across avian malaria parasites.

Phylogeny of seven Bulinus species originating from endemic areas in three African countries, in relation to the human blood fluke Schistosoma haematobium.

BackgroundSnails species belonging to the genus Bulinus (Planorbidae) serve as intermediate host for flukes belonging to the genus Schistosoma (Digenea, Platyhelminthes). Despite its importance in the transmission of these parasites, the evolutionary history of this genus is still obscure. In the present study, we used the partial mitochondrial cytochrome oxidase subunit I (cox1) gene, and the nuclear ribosomal ITS, 18S and 28S genes to investigate the haplotype diversity and phylogeny of seven Bulinus species originating from three endemic countries in Africa (Cameroon, Senegal and Egypt).ResultsThe cox1 region showed much more variation than the ribosomal markers within Bulinus sequences. High levels of genetic diversity were detected at all loci in the seven studied species, with clear segregation between individuals and appearance of different haplotypes, even within same species from the same locality. Sequences clustered into two lineages; (A) groups Bulinus truncatus, B. tropicus, B. globosus and B. umbilicatus; while (B) groups B. forskalii, B. senegalensis and B. camerunensis. Interesting patterns emerge regarding schistosome susceptibility: Bulinus species with lower genetic diversity are predicted to have higher infection prevalence than those with greater diversity in host susceptibility.ConclusionThe results reported in this study are very important since a detailed understanding of the population genetic structure of Bulinus is essential to understand the epidemiology of many schistosome parasites.

Influence of annual rainfall on epidemiology of gastrointestinal parasites in sheep flocks of Rajasthan

The translation of exogenous stages of gastrointestinal (GI) parasites varies according to climatic variables like temperature, rainfall and humidity. The present paper describes the influence of quantum of annual rainfall on the prevalence and intensity of GI parasites in field flocks of sheep in Rajasthan. The period of 9 years (2004–13) was divided in 3 categories as years with above normal, normal and below normal annual total rainfall (TRF). Faecal samples (59,398) were subjected to qualitative and quantitative evaluation and data on monthly incidence and intensity were analyzed according to categories of years. The effect of annual TRF was significant on incidence of strongyle worms for all the months except during June in semi-arid and April in arid region. During August to December (favourable season), it was higher in the years with below normal TRF in semi-arid and in the years with normal annual TRF in arid region. The incidence of Trichuris spp, Strongyloides papillosus, Fasciola gigantica and Schistosoma indicum was very low. Incidence of S. papillosus was higher in the years of normal annual TRF in semi-arid region only. The incidence of Amphistomes remained lowest in the years of normal annual TRF. Higher annual TRF resulted in lower monthly incidence of Moneizia infection. The intensity of strongyle infection for all the months was significantly lower in years with above normal annual TRF in semi-arid region however similar influence was noticed only for July and August in arid region. It was inferred that moderate flexibility in single drench schedule according to magnitude of annual rainfall effectively managed the GI nematodes in field flocks of Rajasthan. However, a different strategy is required to formulate for management of flukes depending on quantum of rainfall, availability of water reservoirs and water resources for flocks.

An epidemiological survey of bovine Babesia and Theileria parasites in cattle, buffaloes, and sheep in Egypt

Cattle, buffaloes, and sheep are the main sources of meat and milk in Egypt, but their productivity is thought to be greatly reduced by hemoprotozoan parasitic diseases. In this study, we analyzed the infection rates of Babesia bovis, Babesia bigemina, Theileria annulata, and Theileria orientalis, using parasite-specific PCR assays in blood–DNA samples sourced from cattle (n=439), buffaloes (n=50), and sheep (n=105) reared in Menoufia, Behera, Giza, and Sohag provinces of Egypt. In cattle, the positive rates of B. bovis, B. bigemina, T. annulata, and T. orientalis were 3.18%, 7.97%, 9.56%, and 0.68%, respectively. On the other hand, B. bovis and T. orientalis were the only parasites detected in buffaloes and each of these parasites was only found in two individual DNA samples (both 2%), while one (0.95%) and two (1.90%) of the sheep samples were positive for B. bovis and B. bigemina, respectively. Sequence analysis showed that the B. bovis Rhoptry Associated Protein-1 and the B. bigemina Apical Membrane Antigen-1 genes were highly conserved among the samples, with 99.3–100% and 95.3–100% sequence identity values, respectively. In contrast, the Egyptian T. annulata merozoite surface antigen-1 gene sequences were relatively diverse (87.8–100% identity values), dispersing themselves across several clades in the phylogenetic tree containing sequences from other countries. Additionally, the T. orientalis Major Piroplasm Surface Protein (MPSP) gene sequences were classified as types 1 and 2. This is the first report of T. orientalis in Egypt, and of type 2 MPSP in buffaloes. Detection of MPSP type 2, which is considered a relatively virulent genotype, suggests that T. orientalis infection may have veterinary and economic significance in Egypt. In conclusion, the present study, which analyzed multiple species of Babesia and Theileria parasites in different livestock animals, may shed an additional light on the epidemiology of hemoprotozoan parasites in Egypt.

The parasitic phase of Ostertagia ostertagi: quantification of the main life history traits through systematic review and meta-analysis

Predictive models of parasite life cycles increase our understanding of how parasite epidemiology is influenced by global changes and can be used to support decisions for more targeted worm control. Estimates of parasite population dynamics are needed to parameterize such models. The aim of this study was to quantify the main life history traits of Ostertagia ostertagi, economically the most important nematode of cattle in temperate regions. The main parameters determining parasite density during the parasitic phase of O. ostertagi are (i) the larval establishment rate, (ii) hypobiosis rate, (iii) adult mortality and (iv) female fecundity (number of eggs laid per day per female). A systematic review was performed covering studies from 1962 to 2007, in which helminth-naïve calves were artificially infected with O. ostertagi. The database was further extended with results of unpublished trials conducted at the Laboratory for Parasitology of Ghent University, Belgium. Overall inverse variance weighted estimates were computed for each of the traits through random effects models. An average establishment rate (±S.E.) of 0.269±0.022 was calculated based on data of 27 studies (46 experiments). The establishment rate declined when infection dose increased and was lower in younger animals. An average proportion of larvae entering hypobiosis (±S.E.) of 0.041 (±0.009) was calculated based on 27 studies (54 experiments). The proportion of ingested larvae that went into hypobiosis was higher in animals that received concomitant infections with nematode species other than O. ostertagi (mixed infections). An average daily adult mortality (±S.E.) of 0.028 (±0.002) was computed based on data from 28 studies (70 experiments). Adult mortality was positively correlated with infection dose. A daily fecundity (±S.E.) of 284 (±45) eggs per female was found based on nine studies (10 experiments). The average female sex ratio of O. ostertagi based on individual animal data (n=75) from six different studies was estimated to be 0.55. We believe that this systematic review is the first to summarise the available data on the main life history traits of the parasitic phase of O. ostertagi. In conclusion, this meta-analysis provides novel estimates for the parameterization of life cycle-based transmission models, explicitly reports measures of variance around these estimates, gives evidence for density dependence of larval establishment and adult mortality, shows that host age affects larval establishment and, to our knowledge, provides the first evidence for O. ostertagi of a female-biased sex ratio.

Review of the interactions between G6PD deficiency and primaquine therapy for malaria control and elimination

Primaquine is an essential drug for malaria control and elimination by being the only drug active against the liver-reservoir of Plasmodium vivax infections and also the only drug against the mature sexual stages of Plasmodium falciparum which are responsible for onward transmission to mosquitoes. Nevertheless, uncertainty associated with this drug’s safety results in under-use due to difficulties with diagnosing glucose-6-phosphate dehydrogenase deficiency (G6PDd) in point-of-care settings. This common genetic disorder makes patients susceptible to potentially severe, and occasionally even fatal, primaquine-induced haemolysis. Policy shifts towards malaria elimination in recent years have led to a surge of clinical trials and reviews of historical data to promote safe primaquine use. This talk will examine evidence of the drug’s use and outcomes in geographic regions with distinct epidemiological characteristics. For each setting, the parasite epidemiology, the population’s G6PDd characteristics, and the current primaquine policies will be discussed. The quality and completeness of the parasitological, G6PDd and clinical evidence-bases that inform primaquine policy is examined; the importance of context-specific evaluations of primaquine use is emphasized.

Molecular assessment of Hepatozoon (Apicomplexa: Adeleorina) infections in wild canids and rodents from north Africa, with implications for transmission dynamics across taxonomic groups.

Parasites play a major role in ecosystems, and understanding of host-parasite interactions is important for predicting parasite transmission dynamics and epidemiology. However, there is still a lack of knowledge about the distribution, diversity, and impact of parasites in wildlife, especially from remote areas. Hepatozoon is a genus of apicomplexan parasites that is transmitted by ingestion of infected arthropod vectors. However, alternative modes of transmission have been identified such as trophic transmission. Using the 18S rRNA gene as a marker, we provide an assessment of Hepatozoon prevalence in six wild canid and two rodent species collected between 2003 and 2012 from remote areas in North Africa. By combining this with other predator-prey systems in a phylogenetic framework, we investigate Hepatozoon transmission dynamics in distinct host taxa. Prevalence was high overall among host species (African jerboa Jaculus jaculus [17/47, 36%], greater Egyptian jerboa Jaculus orientalis [5/7, 71%], side-striped jackal Canis adustus [1/2, 50%], golden jackal Canis aureus [6/32, 18%], pale fox Vulpes pallida [14/28, 50%], Rüppell's fox Vulpes rueppellii [6/11, 55%], red fox Vulpes vulpes [8/16, 50%], and fennec fox Vulpes zerda [7/11, 42%]). Phylogenetic analysis showed further evidence of occasional transmission of Hepatozoon lineages from prey to canid predators, which seems to occur less frequently than in other predator-prey systems such as between snakes and lizards. Due to the complex nature of the Hepatozoon lifecycle (heteroxenous and vector-borne), future studies on these wild host species need to clarify the dynamics of alternative modes of Hepatozoon transmission and identify reservoir and definitive hosts in natural populations. We also detected putative Babesia spp. (Apicomplexa: Piroplasmida) infections in two canid species from this region, V. pallida (1/28) and V. zerda (1/11).