Serological evidence of single and mixed infections of Rift Valley fever virus,Brucella spp. and Coxiella burnetii in dromedary camels in Kenya

Camels are increasingly becoming the livestock of choice for pastoralists reeling from effects of climate change in semi-arid and arid parts of Kenya. As the population of camels rises, better understanding of their role in the epidemiology of zoonotic diseases in Kenya is a public health priority. Rift Valley fever (RVF), brucellosis and Q fever are three of the top priority diseases in the country but the involvement of camels in the transmission dynamics of these diseases is poorly understood. We analyzed 120 camel serum samples from northern Kenya to establish seropositivity rates of the three pathogens and to characterize the infecting Brucella species using molecular assays. We found seropositivity of 24.2% (95% confidence interval [CI]: 16.5–31.8%) for Brucella, 20.8% (95% CI: 13.6–28.1%) and 14.2% (95% CI: 7.9–20.4%) for Coxiella burnetii and Rift valley fever virus respectively. We found 27.5% (95% CI: 19.5–35.5%) of the animals were seropositive for at least one pathogen and 13.3% (95% CI: 7.2–19.4%) were seropositive for at least two pathogens. B. melitensis was the only Brucella spp. detected. The high sero-positivity rates are indicative of the endemicity of these pathogens among camel populations and the possible role the species has in the epidemiology of zoonotic diseases. Considering the strong association between human infection and contact with livestock for most zoonotic infections in Kenya, there is immediate need to conduct further research to determine the role of camels in transmission of these zoonoses to other livestock species and humans. This information will be useful for designing more effective surveillance systems and intervention measures.     

Current knowledge of vector-borne zoonotic pathogens in Zambia: A clarion call to scaling-up “One Health” research in the wake of emerging and re-emerging infectious diseases

BackgroundAlthough vector-borne zoonotic diseases are a major public health threat globally, they are usually neglected, especially among resource-constrained countries, including those in sub-Saharan Africa. This scoping review examined the current knowledge and identified research gaps of vector-borne zoonotic pathogens in Zambia.Methods and findingsMajor scientific databases (Web of Science, PubMed, Scopus, Google Scholar, CABI, Scientific Information Database (SID)) were searched for articles describing vector-borne (mosquitoes, ticks, fleas and tsetse flies) zoonotic pathogens in Zambia. Several mosquito-borne arboviruses have been reported including Yellow fever, Ntaya, Mayaro, Dengue, Zika, West Nile, Chikungunya, Sindbis, and Rift Valley fever viruses. Flea-borne zoonotic pathogens reported include Yersinia pestis and Rickettsia felis. Trypanosoma sp. was the only tsetse fly-borne pathogen identified. Further, tick-borne zoonotic pathogens reported included Crimean-Congo Haemorrhagic fever virus, Rickettsia sp., Anaplasma sp., Ehrlichia sp., Borrelia sp., and Coxiella burnetii.ConclusionsThis study revealed the presence of many vector-borne zoonotic pathogens circulating in vectors and animals in Zambia. Though reports of human clinical cases were limited, several serological studies provided considerable evidence of zoonotic transmission of vector-borne pathogens in humans. However, the disease burden in humans attributable to vector-borne zoonotic infections could not be ascertained from the available reports and this precludes the formulation of national policies that could help in the control and mitigation of the impact of these diseases in Zambia. Therefore, there is an urgent need to scale-up “One Health” research in emerging and re-emerging infectious diseases to enable the country to prepare for future epidemics, including pandemics.     

Candidatus Bartonella merieuxii,a Potential New Zoonotic Bartonella Species in Canids from Iraq

Bartonellae are emerging vector-borne pathogens infecting erythrocytes and endothelial cells of various domestic and wild mammals. Blood samples were collected from domestic and wild canids in Iraq under the United States Army zoonotic disease surveillance program. Serology was performed using an indirect immunofluorescent antibody test for B. henselae, B. clarridgeiae, B. vinsonii subsp. berkhoffii and B. bovis. Overall seroprevalence was 47.4% in dogs (n = 97), 40.4% in jackals (n = 57) and 12.8% in red foxes (n = 39). Bartonella species DNA was amplified from whole blood and representative strains were sequenced. DNA of a new Bartonella species similar to but distinct from B. bovis, was amplified from 37.1% of the dogs and 12.3% of the jackals. B. vinsonii subsp. berkhoffii was also amplified from one jackal and no Bartonella DNA was amplified from foxes. Adjusting for age, the odds of dogs being Bartonella PCR positive were 11.94 times higher than for wild canids (95% CI: 4.55–31.35), suggesting their role as reservoir for this new Bartonella species. This study reports on the prevalence of Bartonella species in domestic and wild canids of Iraq and provides the first detection of Bartonella in jackals. We propose Candidatus Bartonella merieuxii for this new Bartonella species. Most of the Bartonella species identified in sick dogs are also pathogenic for humans. Therefore, seroprevalence in Iraqi dog owners and bacteremia in Iraqi people with unexplained fever or culture negative endocarditis requires further investigation as well as in United States military personnel who were stationed in Iraq. Finally, it will also be essential to test any dog brought back from Iraq to the USA for presence of Bartonella bacteremia to prevent any accidental introduction of a new Bartonella species to the New World.     

Bartonella spp. in Fruit Bats and Blood-Feeding Ectoparasites in Madagascar

We captured, ectoparasite-combed, and blood-sampled cave-roosting Madagascan fruit bats (Eidolon dupreanum) and tree-roosting Madagascan flying foxes (Pteropus rufus) in four single-species roosts within a sympatric geographic foraging range for these species in central Madagascar. We describe infection with novel Bartonella spp. in sampled Eidolon dupreanum and associated bat flies (Cyclopodia dubia), which nest close to or within major known Bartonella lineages; simultaneously, we report the absence of Bartonella spp. in Thaumapsylla sp. fleas collected from these same bats. This represents the first documented finding of Bartonella infection in these species of bat and bat fly, as well as a new geographic record for Thaumapsylla sp. We further relate the absence of both Bartonella spp. and ectoparasites in sympatrically sampled Pteropus rufus, thus suggestive of a potential role for bat flies in Bartonella spp. transmission. These findings shed light on transmission ecology of bat-borne Bartonella spp., recently demonstrated as a potentially zoonotic pathogen.     

Parasites and pathogens in wild populations of water voles (Arvicola amphibius) in the UK

The water vole (Arvicola amphibius) is Britain’s most endangered mammal, having gained protection under Schedule 5 of the Wildlife and Countryside Act in 2008. We present an overview of a range of naturally occurring pathogens and parasites in this rare species, which might negatively impact population persistence for small or declining populations. Wild water voles were live-captured in 2004 and 2006 from sites throughout the UK and were screened for a range of pathogens. These included: Puumala virus, Campylobacter spp., Escherichia coli, Salmonella enterica, Leptospira spp., Bartonella spp., Toxoplasma gondii, Giardia spp., Cryptosporidium spp., Babesia microti and Trypanosoma spp. E. coli was the most prevalent with 46/74 (62.2%; 95% CI, 51–73) individuals infected. One vole was co-infected with seven different pathogens whilst 20% of individuals were pathogen-free.     

Rickettsial agents in Egyptian ticks collected from domestic animals

To assess the presence of rickettsial pathogens in ticks from Egypt, we collected ticks from domestic and peridomestic animals between June 2002 and July 2003. DNA extracts from 1019 ticks were tested, using PCR and sequencing, for Anaplasma spp., Bartonella spp., Coxiella burnetii, Ehrlichia spp., and Rickettsia spp. Ticks included: 29 Argas persicus, 10 Hyalomma anatolicum anatolicum, 55 Hyalomma anatolicum excavatum, 174 Hyalomma dromedarii, 2 Hyalomma impeltatum, 3 Hyalomma marginatum rufipes, 55 unidentified nymphal Hyalomma, 625 Rhipicephalus (Boophilus) annulatus, 49 Rhipicephalus sanguineus, and 17 Rhipicephalus turanicus. Ticks were collected predominantly (>80%) from buffalo, cattle, and camels, with smaller numbers from chicken and rabbit sheds, sheep, foxes, a domestic dog, a hedgehog, and a black rat. We detected Anaplasma marginale, Coxiella burnetii, Rickettsia aeschlimannii, and four novel genotypes similar to: “Anaplasma platys,” Ehrlichia canis, Ehrlichia spp. reported from Asian ticks, and a Rickettsiales endosymbiont of Ixodes ricinus.     

The Recent Evolution of a Maternally-Inherited Endosymbiont of Ticks Led to the Emergence of the Q Fever Pathogen,Coxiella burnetii

Q fever is a highly infectious disease with a worldwide distribution. Its causative agent, the intracellular bacterium Coxiella burnetii, infects a variety of vertebrate species, including humans. Its evolutionary origin remains almost entirely unknown and uncertainty persists regarding the identity and lifestyle of its ancestors. A few tick species were recently found to harbor maternally-inherited Coxiella-like organisms engaged in symbiotic interactions, but their relationships to the Q fever pathogen remain unclear. Here, we extensively sampled ticks, identifying new and atypical Coxiella strains from 40 of 58 examined species, and used this data to infer the evolutionary processes leading to the emergence of C. burnetii. Phylogenetic analyses of multi-locus typing and whole-genome sequencing data revealed that Coxiella-like organisms represent an ancient and monophyletic group allied to ticks. Remarkably, all known C. burnetii strains originate within this group and are the descendants of a Coxiella-like progenitor hosted by ticks. Using both colony-reared and field-collected gravid females, we further establish the presence of highly efficient maternal transmission of these Coxiella-like organisms in four examined tick species, a pattern coherent with an endosymbiotic lifestyle. Our laboratory culture assays also showed that these Coxiella-like organisms were not amenable to culture in the vertebrate cell environment, suggesting different metabolic requirements compared to C. burnetii. Altogether, this corpus of data demonstrates that C. burnetii recently evolved from an inherited symbiont of ticks which succeeded in infecting vertebrate cells, likely by the acquisition of novel virulence factors.     

Molecular evidence for a novel <Emphasis Type="Italic">Coxiella</Emphasis> from <Emphasis Type="Italic">Argas monolakensis</Emphasis> (Acari: Argasidae) from Mono Lake,California, USA

Argasid ticks are vectors of viral and bacterial agents of humans and animals. Recent reports indicate that some ornithophilic argasids harbored rickettsial agents. A Nearctic tick, Argas monolakensis Schwan, Corwin, Brown is ornithophilic and has not previously been examined for rickettsial agents. Thirty adult A. monolakensis were tested by PCR for DNA from Rickettsia or Coxiella. Amplicons from a Coxiella sp. that were divergent from Coxiella burnetii were detected in 16/30 A. monolakensis. These molecular isolates were similar but not identical to C. burnetii, the Coxiella spp. of other ticks, and “Coxiella cheraxi” a pathogen of crayfish. The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.     

Tick-Borne Zoonotic Bacteria in Wild and Domestic Small Mammals in Northern Spain

The prevalence and diversity of tick-borne zoonotic bacteria (Borrelia spp., Anaplasma phagocytophilum, Coxiella burnetii, and spotted fever group rickettsiae) infecting 253 small mammals captured in the Basque Country (Spain) were assessed using PCR and reverse line blot hybridization. Trapping sites were selected around sheep farms (study 1, 2000 to 2002) and recreational parks (study 2, 2003 to 2005). The majority of the studied mammals (162) were wood mice (Apodemus sylvaticus), but six other different species were also analyzed: yellow-necked mice (Apodemus flavicollis), shrews (Crocidura russula and Sorex coronatus), bank voles (Clethrionomys glareolus), domestic mice (Mus domesticus), and moles (Talpa europaea). The results showed an infection rate ranging from 10.7% to 68.8%, depending on the small mammal species. One C. russula shrew and one A. sylvaticus mouse gave positive reactions for A. phagocytophilum, and C. burnetii was detected in two domestic mice and one A. sylvaticus mouse in a farm. The DNA of Borrelia spp. was detected in 67 animals (26.5%), most of them presenting positive hybridization with the probe for Borrelia sp. strain R57, the new Borrelia species previously detected in small mammals in our region. Furthermore, a second PCR and reverse line blot hybridization specific for B. burgdorferi sensu lato revealed the presence of Borrelia afzelii in 6.3% of C. glareolus voles and 14.3% of S. coronatus shrews. All small mammals were negative for spotted fever group rickettsiae. These results highlight the relevance of small mammals as reservoirs of some zoonotic bacteria.     

Diversity of Bartonella and Rickettsia spp. in Bats and Their Blood-Feeding Ectoparasites from South Africa and Swaziland

In addition to several emerging viruses, bats have been reported to host multiple bacteria but their zoonotic threats remain poorly understood, especially in Africa where the diversity of bats is important. Here, we investigated the presence and diversity of Bartonella and Rickettsia spp. in bats and their ectoparasites (Diptera and Siphonaptera) collected across South Africa and Swaziland. We collected 384 blood samples and 14 ectoparasites across 29 different bat species and found positive samples in four insectivorous and two frugivorous bat species, as well as their Nycteribiidae flies. Phylogenetic analyses revealed diverse Bartonella genotypes and one main group of Rickettsia, distinct from those previously reported in bats and their ectoparasites, and for some closely related to human pathogens. Our results suggest a differential pattern of host specificity depending on bat species. Bartonella spp. identified in bat flies and blood were identical supporting that bat flies may serve as vectors. Our results represent the first report of bat-borne Bartonella and Rickettsia spp. in these countries and highlight the potential role of bats as reservoirs of human bacterial pathogens.     

Rickettsial pathogens in the tropical rat mite Ornithonyssus bacoti (Acari: Macronyssidae) from Egyptian rats (Rattus spp.)

We collected and tested 616 tropical rat mites (Ornithonyssus bacoti (Hirst)) from rats (Rattus norvegicus (Berkenhout) and R. rattus (Linnaeus)) throughout 14 governorates in Egypt and tested DNA extracts from pools of these mites for Bartonella spp., Coxiella burnetii, and Rickettsia spp. by PCR amplification and sequencing. Three different mite-associated bacterial agents, including one Bartonella and two Rickettsia spp., were detected in eight pools of mites. Further research could demonstrate the vector potential of mites and pathogenicity of these agents to humans or animals. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.     

Zoonotic Enterobacterial Pathogens Detected in Wild Chimpanzees

Infectious diseases including those acquired through direct or indirect contact with people and livestock threaten the survival of wild great apes. Few studies have reported enterobacterial pathogens in chimpanzees. We used multiplex PCR to screen faeces of chimpanzees sharing a landscape with villagers and livestock in Bulindi, Uganda for Salmonella spp., enterohemorrhagic Escherichia coli (E. coli) and Shigella spp./enteroinvasive E. coli. All three potentially zoonotic pathogens were detected. Individual prevalence ranged between 7 and 20%, with most infections observed in mature male chimpanzees. These preliminary findings suggest detailed investigation of enterobacterial infections in people, primates and livestock in this ecosystem is warranted.     

The Absence of Zoonotic Agents in Invasive Bullfrogs (Lithobates catesbeianus) in Belgium and The Netherlands

Exotic invasive bullfrogs (Lithobates catesbeianus) are considered to exert a considerable negative impact on native amphibian communities. This can be due to competition and predation, but they are also a notorious source of the infectious diseases chytridiomycosis and ranavirosis, affecting amphibian populations globally. Little is known regarding their carriage of other microbial agents that might be transferred to humans or other animals. In this study we determined the occurrence of the amphibian pathogens Ranavirus and Batrachochytrium dendrobatidis and of the zoonotic agents Coxiella burnetii, Neospora caninum, Leptospira sp., Toxoplasma gondii, Mycoplasma sp., Campylobacter sp., Salmonella sp. and extended-spectrum beta-lactamase producing Escherichia coli in 164 bullfrogs from three populations in Belgium and The Netherlands. Although B. dendrobatidis was present at a high prevalence of 63%, mean infection loads were low with an average of 10.9 genomic equivalents (SD 35.5), confirming the role of bullfrogs as B. dendrobatidis carriers, but questioning their role as primary reservoirs for B. dendrobatidis transmission to native amphibian communities. All tested samples were negative for the other infectious agents examined. These results suggest a limited role of bullfrogs as carrier of these pathogens.     

Bartonella spp. Bacteremia in Blood Donors from Campinas,Brazil

Bartonella species are blood-borne, re-emerging organisms, capable of causing prolonged infection with diverse disease manifestations, from asymptomatic bacteremia to chronic debilitating disease and death. This pathogen can survive for over a month in stored blood. However, its prevalence among blood donors is unknown, and screening of blood supplies for this pathogen is not routinely performed. We investigated Bartonella spp. prevalence in 500 blood donors from Campinas, Brazil, based on a cross-sectional design. Blood samples were inoculated into an enrichment liquid growth medium and sub-inoculated onto blood agar. Liquid culture samples and Gram-negative isolates were tested using a genus specific ITS PCR with amplicons sequenced for species identification. Bartonella henselae and Bartonella quintana antibodies were assayed by indirect immunofluorescence. B. henselae was isolated from six donors (1.2%). Sixteen donors (3.2%) were Bartonella-PCR positive after culture in liquid or on solid media, with 15 donors infected with B. henselae and one donor infected with Bartonella clarridgeiae. Antibodies against B. henselae or B. quintana were found in 16% and 32% of 500 blood donors, respectively. Serology was not associated with infection, with only three of 16 Bartonella-infected subjects seropositive for B. henselae or B. quintana. Bartonella DNA was present in the bloodstream of approximately one out of 30 donors from a major blood bank in South America. Negative serology does not rule out Bartonella spp. infection in healthy subjects. Using a combination of liquid and solid cultures, PCR, and DNA sequencing, this study documents for the first time that Bartonella spp. bacteremia occurs in asymptomatic blood donors. Our findings support further evaluation of Bartonella spp. transmission which can occur through blood transfusions.     

Prevalence and Phylogenetic Analysis of <Emphasis Type="Italic">Bartonella</Emphasis> Species of Wild Carnivores and Their Fleas in Northwestern Mexico

The host–parasite–vector relationship of Bartonella spp. system in wild carnivores and their fleas from northwestern Mexico was investigated. Sixty-six carnivores belonging to eight species were sampled, and 285 fleas belonging to three species were collected during spring (April–May) and fall (October–November) seasons. We detected Bartonella species in 7 carnivores (10.6%) and 27 fleas (9.5%) through either blood culture or PCR. Of the 27 Bartonella-positive fleas, twenty-two were Pulex simulans, three were Pulex irritans and one was Echidnophaga gallinacea. The gltA gene and ITS region sequences alignment revealed six and eight genetic variants of Bartonella spp., respectively. These variants were clustered into Bartonella rochalimae, Bartonella vinsonii subsp. berkhoffii and another genotype, which likely represents a novel species of Bartonella spp. Although experimental infection studies are required to prove the vector role of P. simulans, our results suggest that this flea may play an important role in the Bartonella transmission. The results indicated possible host-specific relationships between Bartonella genotypes and the families of the carnivores, but further studies are needed to verify this finding. The presence of zoonotic species of Bartonella spp. in wild carnivores raises the issue of their potential risk for humans in fragmented ecosystems.     

Spatiotemporal Analysis of Cryptosporidium Species/Genotypes and Relationships with Other Zoonotic Pathogens in Surface Water from Mixed-Use Watersheds

Nearly 690 raw surface water samples were collected during a 6-year period from multiple watersheds in the South Nation River basin, Ontario, Canada. Cryptosporidium oocysts in water samples were enumerated, sequenced, and genotyped by detailed phylogenetic analysis. The resulting species and genotypes were assigned to broad, known host and human infection risk classes. Wildlife/unknown, livestock, avian, and human host classes occurred in 21, 13, 3, and <1% of sampled surface waters, respectively. Cryptosporidium andersoni was the most commonly detected livestock species, while muskrat I and II genotypes were the most dominant wildlife genotypes. The presence of Giardia spp., Salmonella spp., Campylobacter spp., and Escherichia coli O157:H7 was evaluated in all water samples. The greatest significant odds ratios (odds of pathogen presence when host class is present/odds of pathogen presence when host class is absent) for Giardia spp., Campylobacter spp., and Salmonella spp. in water were associated, respectively, with livestock (odds ratio of 3.1), avian (4.3), and livestock (9.3) host classes. Classification and regression tree analyses (CART) were used to group generalized host and human infection risk classes on the basis of a broad range of environmental and land use variables while tracking cooccurrence of zoonotic pathogens in these groupings. The occurrence of livestock-associated Cryptosporidium was most strongly related to agricultural water pollution in the fall (conditions also associated with elevated odds ratios of other zoonotic pathogens occurring in water in relation to all sampling conditions), whereas wildlife/unknown sources of Cryptosporidium were geospatially associated with smaller watercourses where urban/rural development was relatively lower. Conditions that support wildlife may not necessarily increase overall human infection risks associated with Cryptosporidium since most Cryptosporidium genotypes classed as wildlife in this study (e.g., muskrat I and II genotype) do not pose significant infection risks to humans. Consequently, from a human health perspective, land use practices in agricultural watersheds that create opportunities for wildlife to flourish should not be rejected solely on the basis of their potential to increase relative proportions of wildlife fecal contamination in surface water. The present study suggests that mitigating livestock fecal pollution in surface water in this region would likely reduce human infection risks associated with Cryptosporidium and other zoonotic pathogens.     

Animal board invited review: Risks of zoonotic disease emergence at the interface of wildlife and livestock systems

The ongoing coronavirus disease 19s pandemic has yet again demonstrated the importance of the human-animal interface in the emergence of zoonotic diseases, and in particular the role of wildlife and livestock species as potential hosts and virus reservoirs. As most diseases emerge out of the human-animal interface, a better understanding of the specific drivers and mechanisms involved is crucial to prepare for future disease outbreaks. Interactions between wildlife and livestock systems contribute to the emergence of zoonotic diseases, especially in the face of globalization, habitat fragmentation and destruction and climate change. As several groups of viruses and bacteria are more likely to emerge, we focus on pathogenic viruses of the Bunyavirales, Coronaviridae, Flaviviridae, Orthomyxoviridae, and Paramyxoviridae, as well as bacterial species including Mycobacterium sp., Brucella sp., Bacillus anthracis and Coxiella burnetii. Noteworthy, it was difficult to predict the drivers of disease emergence in the past, even for well-known pathogens. Thus, an improved surveillance in hotspot areas and the availability of fast, effective, and adaptable control measures would definitely contribute to preparedness. We here propose strategies to mitigate the risk of emergence and/or re-emergence of prioritized pathogens to prevent future epidemics.     

First identification of Trypanosoma vivax among camels (Camelus dromedarius) in Yazd,central Iran,jointly with Trypanosoma evansi

Trypanosomes are protozoan parasites of class Kinetoplastida. Trypanosoma vivax is one of the organisms that can cause Nagana and Trypanosoma evansi can cause Surra. In Africa, Trypanosoma vivax is mainly transmitted by Glossina spp. (tsetse fly) but it can be transmitted mechanically by other blood-feeding dipters. Trypanosoma evansi is transmitted mechanically and non-dependent to tsetse fly. In this research, T. vivax and T. evansi among camels (Camelus dromedarius) in Yazd, Iran were identified by microscopy and molecular examinations but the sensitivity of microscopy was lower than molecular examinations. Trypanosoma vivax and T. evansi were observed in 4 out of 134 blood film samples (2.98%). The prevalence of Trypanosoma spp. among 134 male camels (C. dromedarius) based on molecular examinations was 30.6% (22.76–38.44% with 95% confidence interval), 25 out of 134 (18.65%) had co-infection of T. evansi and T. vivax, and 16 out of 134 (11.94%) had an infection of T. vivax alone. We provided the first confirmation of infection with T. vivax among camels in Iran, and also in Asia, which has important implications on our knowledge of the occurrence and possible spread of this pathogen at the global level. Investigations in other species such as cattle and sheep are strongly recommended.     

Focus: Zoonotic Disease: New Series of Imidazoles Showed Promising Growth Inhibitory and Curative Potential Against Trypanosoma Infection

The Trypanosoma spp. cause animal and human trypanosomiasis characterized with appreciable health and economic burden mostly in developing nations. There is currently no effective therapy for this parasitic disease, due to poor drug efficacy, drug resistance, and unwanted toxicity, etc. Therefore, new anti-Trypanosoma agents are urgently needed. This study explored new series of imidazoles for anti-Trypanosoma properties in vitro and in vivo. The imidazoles showed moderate to strong and specific action against growth of T. congolense. For example, the efficacy of the imidazole compounds to restrict Trypanosoma growth in vitro was ≥ 12-fold specific towards T. congolense relative to the mammalian cells. Additionally, the in vivo study revealed that the imidazoles exhibited promising anti-Trypanosoma efficacy corroborating the in vitro anti-parasite capacity. In particular, three imidazole compounds (C1, C6, and C8) not only cleared the systemic parasite burden but cured infected rats after no death was recorded. On the other hand, the remaining five imidazole compounds (C2, C3, C4, C5, and C7) drastically reduced the systemic parasite load while extending survival time of the infected rats by 14 days as compared with control. Untreated control died 3 days post-infection, while the rats treated with diminazene aceturate were cured comparable to the results obtained for C1, C6, and C8. In conclusion, this is the first study demonstrating the potential of these new series of imidazoles to clear the systemic parasite burden in infected rats. Furthermore, a high selectivity index of imidazoles towards T. congolense in vitro and the oral LD₅₀ in rats support anti-parasite specific action. Together, findings support the anti-parasitic prospects of the new series of imidazole derivatives.     

Focus: Zoonotic Disease: Zoonotic Ocular Onchocercosis by Onchocerca lupi

The parasitic filarioid Onchocerca lupi causes ocular disease characterized by conjunctivitis and nodular lesions. This nematode was first described in 1967 in a wolf from Georgia, and since then cases of infection from dogs and cats with ocular onchocercosis and sporadically from humans also with subcutaneous and cervical lesions caused by O. lupi have been reported from the Middle East, Europe, and North America. Due to its zoonotic potential, this parasitic infection has gained attention in the past 20 years. Phylogenetic studies have highlighted the recent divergence of O. lupi from other Onchocerca spp. and the importance of domestication in the evolutionary history of this worm. Moreover, the finding of an O. lupi genotype associated with subclinical and mild infection in the Iberian Peninsula, raises important questions about the pathogenicity of this presently enigmatic parasite.