Rhipicephalus Sanguineus Research Articles

Comparative analysis of tick burden, diversity, and distribution in intensively managed wildlife estates with and without prescribed burning

The connection between ticks and zoonotic diseases in Zambia remains unclear due to limited data on tick distribution in private game reserves. This study examines tick control in three ex-situ game reserves across different agro-ecological regions, Lanagani game ranch in the Chibombo district, Chaminuka game ranch in the Lusaka district, and Choma game ranch in the Choma district. The current study evaluated the burden and diversity of ticks across three different management systems concerning the use of fire as a tick control and management tool. A descriptive cross-sectional study collected 267 ticks from 36 transects across three game ranches in Central, Lusaka, and Southern provinces. These ticks were morphologically identified using the existing taxonomic keys and Olympus DF Plapo 1×4 SN5G 08128 stereomicroscope at the University of Zambia, School of Veterinary Medicine, parasitology laboratory. The Analysis of Variance (ANOVA) was used to compare means between categories and correlation coefficient to determine the strength of the relationship. The collected species included 11 Rhipicephalus species, n=6, (Rhipicephalus appendiculatus, Rhipicephalus evertsi, Rhipicephalus microplus, Rhipicephalus decoloratus, Rhipicephalus sanguineus, Rhipicephalus pulcherus, Rhipicephalus zambeziensis); Amblyomma species n=2, (Amblyomma variagatum, Amblyomma poposum), and Hyalomma species n=2 (Hyalomma Rufipes and Hyalomma truncatum). The most common species were R. evertsi (19.4 %), Amblyomma variagatum 14%, Hyalomma truncatum 11%. Significantly higher (p < 0.05) species diversity and burden were observed in the no-burn management system, whilst no significant differences (p > 0.05) were observed between late and early burning systems. These findings have unveiled, for the first time in Zambia, that employing fire as a management tool substantially reduces both tick diversity and burden in enclosed ex-situ conservancy areas. Regular prescribed burning, regardless of the burning regime, was found to remarkably reduce tick populations in game ranches, particularly in the early burning management system. These findings hold promising implications for ecological public health. Considering this, fire as a management tool effectively reduces tick diversity and burden in closed ex-situ conservancy areas. These findings have far-reaching policy implications when it comes to tick control systems that a government may wish to implement.

Multiple species of canine Rhipicephalus complex detected in Canada

Multiple species of brown dog ticks have been described in the United States and the Caribbean: Rhipicephalus sanguineus sensu stricto (s.s.), also referred to as temperate lineage; R. linnaei (=tropical lineage); and R. rutilus (=southeastern Europe lineage) However, Rhipicephalus spp. are rarely recovered from dogs in Canada. To identify canine Rhipicephalus spp. in Canada and determine the influence of travel history on infestation, ticks morphologically identified as brown dog ticks (n = 93) collected from dogs (n = 13) in British Columbia, Ontario, and Québec, Canada were submitted with information regarding each dog's geographic location and travel history. Nucleic acid was extracted from available individual ticks (n = 86) and PCR was used to amplify sequences of a 12S rRNA mitochondrial gene fragment. Sequences were compared to published reference sequences of known species and a phylogenetic tree constructed. Twenty-three ticks (26.7%) consistent with R. linnaei were identified on seven dogs, including dogs from British Columbia and Ontario, with a median infestation intensity of 2 ticks/dog (mean = 3.3 ticks/dog). Sixty-one ticks (70.9%) consistent with R. sanguineus s.s. were found on two dogs from Québec and Ontario (median = 30.5 ticks/dog; mean = 30.5 ticks/dog). One dog from Ontario was infested with R. rutilus (n = 2) (2.3%). Species could not be determined for ticks from three dogs from Ontario and Québec. Most infested dogs (10/13; 76.9%) had a recent (< 1 month) international travel history. These data confirm that multiple species of canine Rhipicephalus are occasionally found in Canada and suggest introduction following travel is likely responsible for these infestations. Further analysis will allow for greater understanding of the range and diversity of canine Rhipicephalus spp. in North America and may reveal risk factors for infestation.

First report of spotted fever group Rickettsia aeschlimannii in Hyalomma turanicum, Haemaphysalis bispinosa, and Haemaphysalis montgomeryi infesting domestic animals: updates on the epidemiology of tick-borne Rickettsia aeschlimannii.

Tick-borne Rickettsia spp. have long been known as causative agents for zoonotic diseases. We have previously characterized Rickettsia spp. in different ticks infesting a broad range of hosts in Pakistan; however, knowledge regarding Rickettsia aeschlimannii in Haemaphysalis and Hyalomma ticks is missing. This study aimed to obtain a better understanding about R. aeschlimannii in Pakistan and update the knowledge about its worldwide epidemiology. Among 369 examined domestic animals, 247 (66%) were infested by 872 ticks. Collected ticks were morphologically delineated into three genera, namely, Rhipicephalus, Hyalomma, and Haemaphysalis. Adult females were the most prevalent (number ₌ 376, 43.1%), followed by nymphs (303, 34.74%) and males (193, 22.13%). Overall, genomic DNA samples of 223 tick were isolated and screened for Rickettsia spp. by the amplification of rickettsial gltA, ompA, and ompB partial genes using conventional PCR. Rickettsial DNA was detected in 8 of 223 (3.58%) ticks including nymphs (5 of 122, 4.0%) and adult females (3 of 86, 3.48%). The rickettsial gltA, ompA, and ompB sequences were detected in Hyalomma turanicum (2 nymphs and 1 adult female), Haemaphysalis bispinosa (1 nymph and 1 adult female), and Haemaphysalis montgomeryi (2 nymphs and 1 adult female). These rickettsial sequences showed 99.71-100% identity with R. aeschlimannii and phylogenetically clustered with the same species. None of the tested Rhipicephalus microplus, Hyalomma isaaci, Hyalomma scupense, Rhipicephalus turanicus, Hyalomma anatolicum, Rhipicephalus haemaphysaloides, Rhipicephalus sanguineus, Haemaphysalis cornupunctata, and Haemaphysalis sulcata ticks were found positive for rickettsial DNA. Comprehensive surveillance studies should be adopted to update the knowledge regarding tick-borne zoonotic Rickettsia species, evaluate their risks to humans and livestock, and investigate the unexamined cases of illness after tick bite among livestock holders in the country.

Do combinations of fipronil, eugenol and carvacrol have synergistic effects against Rhipicephalus sanguineus?

The tick Rhipicephalus sanguineus is one of the main ectoparasites that affects dogs, causing direct and indirect damage to parasitized animals. Currently, infestation control is mainly carried out by using synthetic acaricidal drugs. However, a decrease in efficacy and an increase in resistance to the main therapeutic protocols against tick infestations have been increasingly reported and confirmed, a factor that has driven research into the potential acaricide activity of natural compounds, including in association with synthetic molecules. The aim of this work was to evaluate whether the combinations of fipronil (FIP) and eugenol (EUG), FIP and carvacrol (CAR), and EUG and CAR would have synergistic effects against immature and unfed adult stages of R. sanguineus through in vitro bioassays. Bioassays were carried out using the larval packet test (FAO 2004) adapted for nymphs and adults. The synergistic activity was explored by combining each solution, based on the estimated LC50, in a 1:1 ratio (FIP: EUG, FIP: CAR and EUG: CAR). CompuSyn software was used to evaluate the various pairwise combinations of FIP, EUG and CAR, checking if there was synergism or antagonism between them. FIP and EUG and FIP and CAR showed combination index (CIn) values above 1.45, indicating antagonism. The synergistic activity between EUG and CAR was verified against all unfed phases of R. sanguineus, since the CIn was below 0.70, a value that indicates synergism. The combination of fipronil with either eugenol or carvacrol presented antagonistic effects against R. sanguineus larvae. On the other hand, carvacrol and eugenol had excellent pharmacological synergism against all tick stages with mortality values in the range of 80 to 100%, including the adult stage, which is less susceptible than immature stages.

Molecular Evidence of Ehrlichia canis (Rickettsiales: Anaplasmataceae) in Ticks (Ixodida: Ixodidae) Associated with Dogs (Carnivora: Canidae) from Nuevo Leon, Mexico.

Background: Ehrlichia canis is transmitted by ticks causing Canine monocytic ehrlichiosis, which is considered one of the most critical tickborne pathogens. Materials and Methods: This study aimed to identify by PCR technique E. canis in ticks associated with dogs from urban and rural homes in Nuevo Leon, Mexico. The study was conducted at 13 localities in eight municipalities from 2012 to 2021. Results: A total of 1873 ticks of three species were captured: Amblyomma tenellum, Dermacentor variabilis, and Rhipicephalus sanguineus s.l. The overall infection rate of E. canis in ticks was 59.12% (149/252). Of the 15 sequences, three haplotypes were identified. Conclusion: The urban transmission cycle of canine ehrlichiosis is demonstrated, where the potential vector is the tick R. sanguineus s.l.

New records of Rhipicephalus linnaei infected by Rickettsia massiliae from Central Mexico.

On the American continent, Rhipicephalus sanguineus s.l. comprises two species: Rhipicephalus linnaei and R. sanguineus s.s. Each species has been identified as a potential vector of at least one of five species of pathogenic bacteria of the genus Rickettsia. In particular, Rickettsia massiliae is one of three species with the greatest importance in public health at the continental level. In Mexico, this species is reported exclusively in the Nearctic states of Baja California and Chihuahua. For this reason, the aim of this work was to provide new records of R. massiliae for the centre of the country derived from active acarological surveillance. During the period of February-October 2019, 29 dogs from six municipalities in the state of Morelos were sampled. Hosts were visually inspected, and ticks were recovered and identified morphologically and molecularly by amplification of the 16S rDNA gene. Subsequently, five genes from members of the genus Rickettsia were amplified and sequenced. A total of 229 (117♀, 98♂ and 14 N) ticks identified as R. linnaei were recovered, two of which were positive for R. massiliae strains related to those recovered from Argentina and the United States. This work provides the second record of R. massiliae infecting R. linnaei in Mexico and the Americas, increasing the geographic distribution of this Rickettsia species in the Neotropical region, and providing information on the possible role of R.linnaei as a potential vector of this microorganism.

Efficacy of D-Limonene Nanoemulsion Against Rhipicephalus annulatus and Rhipicephalus sanguineus Ticks.

Ticks infestation has a negative impact against human and animal health through blood sucking, transmission of blood-borne diseases and also caused economic losses. In the present study the adulticidal, ovicidal and larvicidal activity of D-limonene nanoemulsion (DLN) were evaluated against two tick species; Rhipicephalus annulatus and Rhipicephalus sanguineus. Nanoemulsion form of D-limonene was prepared, and its characteristics were evaluated using a UV spectrophotometer and zeta droplet size measurement. Acetylcholinesterase activity was determined. The results revealed significant adulticidal effect with low LC50 and LC90 for D-limonene pure form (DL) against both adult tick spp. (R. annulatus and R. sanguineus) ((0.958 and 1.559%) and (2.26 and 3.51%), respectively). DLN LC50 and LC90 values were ((1.277 and 2.396) and (3.97 and 7.28), respectively) against R. annulatus and R. sanguineus, respectively. DL and DLN showed significant ovicidal effect against R. sanguineus at high concentrations (10 and 5%). In larval packet test, LC50 and LC90 values of DL were ((1.53 and 2.22%) and (6.81 and 12.07%), respectively) against R. annulatus and R. sanguineus, respectively, while LC50 and LC90 values of DLN were ((6.48 and 11.26%) and (7.82 and 13.59%), respectively) against R. annulatus and R. sanguineus, respectively. Significant acetylcholinesterase inhibition percentage was detected for both ticks spp. which treated by DL and DLN. Pure DL is more effective than DLN form against R. annulatus and R. sanguineus.

Exploring the Larvicidal and Repellent Potential of Taurus Cedar (Cedrus libani) Tar against the Brown Dog Tick (Rhipicephalus sanguineus sensu lato).

This study investigated the potential acaricidal and repellent effects of tar obtained from the Lebanon cedar (Cedrus libani A. Rich.) against the brown dog tick species Rhipicephalus sanguineus sensu lato Latreille (Acari: Ixodidae). The goal was to find an alternative, safe, and effective way to eliminate ticks. Tar is traditionally extracted from cedar trees in the Antalya region of Türkiye. The composition of the tar is primarily characterized by a diverse mixture of terpenes, with β-himachalene (29.16%), α-atlantone (28.7%), ar-turmerone (8.82%), longifolene-(V4) (6.66%), α-himachalene (5.28%), and β-turmerone (5.12%) emerging as the predominant constituents. The toxic effects of tar on tick larvae were studied through larval immersion tests (LIT), and its repellent activity was evaluated using a new larval repellent activity test (LRAT). The results revealed significant acaricidal effects, with mortality rates of 77.7% and 82.2% for the Konyaalti and Kepez strains of the brown dog tick, respectively, in response to a 1% concentration of tar. LC50 and LC90 values were determined as 0.47% and 1.52% for the Kepez strain and 0.58% and 1.63% for the Konyaalti strain, respectively. When comparing the repellent effect of tar to the widely used synthetic repellent DEET, repellency rates of up to 100% were observed. As a result, this study establishes, for the first time, the larvicidal and repellent effects of C. libani tar on ticks.

DEMODICOSIS WITH TICKS INFESTATION AND BABESIOSIS IN A MIXED DOG

Demodicosis is a skin disease that often affects dogs caused by Demodex sp. Babesiosis is a parasitic disease in the erythrocytes that attacks dogs caused by Babesia sp. This paper discusses cases of demodicosis with ticks infestation and babesiosis in a dog. A 6-year-old Shih tzu and local mixed-breed male dog named Dede has skin problems such as hair loss and itching. During clinical examination, the dog had a rancid odor, slow skin turgor, alopecia, erythema, crusting, hyperpigmentation and hemorrhage, accompanied by pruritus and infestation of Rhipicephalus sanguineus ticks. The mucous membranes of the eyes and mouth appear pale. On examination of skin scrapings, Demodex sp. were found. Complete blood count showed that dog had normochromic normocytic anemia, leukocytosis, lymphocytosis, granulocytosis, erythrocytopenia and thrombocytopenia. On examination of the blood smear, protozoa Babesia sp were found. The dog was diagnosed with demodicosis and babesiosis. Treatment is carried out by administering ivermectin, diphenhydramine HCl, clindamycin, caviplex, fish oil, and shampoo containing miconazole nitrate, lime sulfur, salicylic acid, benzoyl peroxide, and triclosan, and spraying the dog's place with deltamethrin. Evaluation on the 7th, 14th and 21st day the dog's condition showed an improvement.

Pet transportation or tourism: risk of moving zoonotic pathogens

Pet transportation has become relevant. However, since adequate sanitary measures are not taken, pets can be carriers of pathogens, such as ticks which at the same time may turn into zoonotic agent vectors. Ticks are frequent ectoparasites in warm areas. However, they may be dispersed in temperate regions such as Mexico City (CDMX) and become responsible for other vector-borne diseases relevant to Veterinary Medicine and/or public health. It shows that moving animals from one place to another, including tourism with pets, can cause dispersion and proliferation of pathogens if the adequate sanitary measures are not taken. Therefore, this article is of great importance from a biological, ecological, public and veterinary health, since it shows the role of humans in the spread of pathogens particularly of Rhipicephalus sanguineus, its introduction to a site otherwise naturally free of them, and the adaptation mechanisms they may display to infect other hosts with the potential to transmit other emerging pathogens.

Effect of Tagetes minuta essential oil on the central nervous system of unfed Rhipicephalus sanguineus sensu lato 'tropical lineage' ticks.

Rhipicephalus sanguineus sensu lato 'tropical lineage' (Acari: Ixodidae) is considered a sanitary concern due to its role as a disease vector. Tick strains resistant to synthetic acaricides have caused difficulties in their control, besides synthetic acaricides are harmful to the environment and to the health of non-target animals. The research of plants with acaricidal and repellent properties has proved to be an efficient alternative in tick control. The genus Tagetes spp. excels for its use as traditional pest control in households and plantations and also for its potential as an acaricide against R. sanguineus under laboratory conditions. The first aim of the present study was to evaluate the effect of different doses of Tagetes minuta essential oil (TMEO) on the central nervous system (synganglion) in unfed R. sanguineus adults. The histological analysis of synganglion exposed to the different concentrations of TMEO and amitraz 12.5% (50% of the recommended dose in the package insert) showed a significant effect with signs of cell damage including volume increase, loss of shape, and vacuolization, in addition to chromatin alterations such as condensation, margination, and fragmentation. TMEO were analyzed by gas chromatography coupled with mass spectrometry showing the presence of 21 compounds that according to their chemical structure are classified as terpenoids. Among them (Z)-β-ocimene, ocimene, (Z)-tagetone, and verbenone were found in major quantities.

Metagenomic exploration of endosymbionts and pathogens in the tropical lineage of Rhipicephalus sanguineus sensu lato (s.l.) ticks in Colombia

Rhipicephalus sanguineus sensu lato (s.l.), commonly known as the domestic dog tick, is a globally distributed tick. This species plays a significant role in human and animal health, as well as in economy due to its ability to infest livestock. The use of shotgun metagenomics has proven valuable in identifying tick-borne pathogens and key members of the tick microbiome, including endosymbionts. However, the application of shotgun metagenomics in R. sanguineus s.l. ticks in Latin America remains largely unexplored. Therefore, our objective aimed to explore and further analyze the metagenome of the tropical lineage of R. sanguineus s.l. ticks in Colombia. Through our analysis, we identified the three most prevalent pathogens harbored by these ticks, namely: Anaplasma phagocytophilum, Francisella tularensis, and Theileria equi. However, the most abundant microorganism detected was not a pathogen but the endosymbiont Coxiella mudrowiae. Interestingly, Coxiella mudrowiae exhibited significant negative correlations with several pathogens and other endosymbionts. Furthermore, we successfully constructed 27 medium-quality metagenome-assembled genomes (MAGs) for this microorganism, enabling us to conduct a pangenome analysis by comparing them with available genomes and identifying proteins of interest, such as those involved in vitamin B synthesis. This study represents the first implementation of shotgun metagenomics as a methodology to expand our understanding of pathogens and endosymbionts in the circulating tropical lineage of R. sanguineus s.l. ticks in Colombia. The findings of this research serve as a foundation for the development of prevention and mitigation strategies against pathogens transmitted by this tick species. Information gained from this study can contribute to the improvement of public health measures and veterinary practices aimed at controlling the impact of tick-borne diseases.

Efficacy of the Vaccine Candidate Based on the P0 Peptide against Dermacentor nitens and Ixodes ricinus Ticks.

The control of ticks through vaccination offers a sustainable alternative to the use of chemicals that cause contamination and the selection of resistant tick strains. However, only a limited number of anti-tick vaccines have reached commercial realization. In this sense, an antigen effective against different tick species is a desirable target for developing such vaccines. A peptide derived from the tick P0 protein (pP0) conjugated to a carrier protein has been demonstrated to be effective against the Rhipicephalus microplus, Rhipicephalus sanguineus, and Amblyomma mixtum tick species. The aim of this work was to assess the efficacy of this peptide when conjugated to the Bm86 protein against Dermacentor nitens and Ixodes ricinus ticks. An RNAi experiment using P0 dsRNA from I. ricinus showed a dramatic reduction in the feeding of injected female ticks on guinea pigs. In the follow-up vaccination experiments, rabbits were immunized with the pP0-Bm86 conjugate and challenged simultaneously with larvae, nymphs, and the adults of I. ricinus ticks. In the same way, horses were immunized with the pP0-Bm86 conjugate and challenged with D. nitens larva. The pP0-Bm86 conjugate showed efficacies of 63% and 55% against I. ricinus and D. nitens ticks, respectively. These results, combined with previous reports of efficacy for this conjugate, show the promising potential for its development as a broad-spectrum anti-tick vaccine.

Seroprevalence and transmission of severe fever with thrombocytopenia syndrome virus in a coastal endemic area in Southeastern China

Severe fever with thrombocytopenia syndrome (SFTS) is a newly emerged tick-borne viral zoonosis and widely prevalent in China, Japan and South Korea. Most reported SFTS cases have been identified in mountainous and hilly areas, with a few in island areas. In this study, we conducted a systematic investigation about natural infection of SFTS virus (SFTSV) among humans, animals and ticks in a coastal endemic prefecture, containing island, plains and mountain settings, in Zhejiang Province, Southeastern China. From July 2020 to June 2021, 1117 participants completed a survey with questionnaire interview and serum testing. Meanwhile, 862 serum samples of domestic animals, 275 spleen tissue samples of wild animals and 829 ticks representing five species (predominantly Haemaphysalis longicornis and Rhipicephalus sanguineus sensu lato) were collected. The seroprevalence of anti-SFTSV total antibody and IgM antibody among the participants was 4.8 % (54/1117) and 0.6 % (7/1117), respectively. Multivariate logistic regression analysis indicated that living in the island area (OR=2.66; 95 %CI: 1.04–6.80; P = 0.041) was significantly associated with seropositivity of total antibody to SFTSV. Furthermore, a higher seroprevalence was observed in domestic animals (36.1 %), while the SFTSV-RNA infection rate was 0.4 % in wild animals and the minimum infection rate (MIR) was 0.8 % for all tick species combined. The only tick species infected with SFTSV was H. longicornis. The prevalence of SFTSV infection in the island area, manifested by anti-SFTSV total antibody (P = 0.012) and IgM antibody (P = 0.004) among humans, anti-SFTSV total antibody (P<0.001) among domestic animals, and SFTSV-RNA among ticks (P = 0.022), was significantly higher than that in the mountainous area and the plain area. Furthermore, phylogenetic analysis showed that SFTSV sequences obtained from ticks in the island area were clustered with reported strains in Japan and South Korea. These results suggest that islands in the study area might be an important natural focus of SFTSV.

Efficacy of either orally administered fluralaner or topically administered imidacloprid/flumethrin for controlling Rhipicephalus sanguineus sensu lato premises infestations

BackgroundAdult, nymph, and larval Rhipicephalus sanguineus sensu lato infest dogs and thrive in premises including homes and kennels. Ticks emerge from hiding to seek and attach to dogs, engorge, then leave their hosts to hide then molt or oviposit. This study evaluated the effect of either external or systemic canine treatment on R. sanguineus s.l. populations in premises.MethodsThirty-two dogs in eight kennels were divided into three groups; one group (eight dogs in two kennels) served as untreated controls; one group (12 dogs in three kennels) received oral fluralaner (25–56 mg/kg); and one group (12 dogs in three kennels) received topical flumethrin/imidacloprid impregnated collars. Treatments were administered once on day 0. Prior to treatment, R. sanguineus s.l. infestations were established in kennels holding dogs, by placing ticks every 2 weeks from day −84 through day −14. Kennel surfaces (walls and floors) were smooth except for uniform “hideouts” to permit precise off-host tick counting.ResultsControl dog kennel mean tick counts (all life stages) increased from 737 ticks/kennel at day −7 to 2213 at day 63 when all control kennel dogs were acaricide-treated as a humane endpoint. Kennels housing dogs subsequently treated with systemic fluralaner had a mean of 637 counted ticks/kennel on study day −7 (7 days before treatment). One fluralaner treatment eliminated all premises ticks (100% reduction) by day 70, and these kennels remained tick-free through study completion (day 84). Kennels housing dogs subsequently treated with an external imidacloprid/flumethrin collar had a mean of 614 counted ticks/kennel at study day −7. Collar treatment reduced counts by 90% on day 63, with kennel tick counts climbing after this and ending the study with a 75% reduction. Systemic fluralaner treatment was significantly (P = 0.003) more effective at reducing engorged adult female tick counts than external imidacloprid/flumethrin treatment.ConclusionsFluralaner treatment eliminated off-host R. sanguineus life stages in infested kennels by day 70 following treatment and was significantly more effective than imidacloprid/flumethrin collar treatment in reducing the premises population of engorged female ticks. Imidacloprid/flumethrin treatment did not eliminate premises tick populations, with populations increasing before the study end.Graphical

Boutonneuse Fever in Southeastern Romania.

Boutonneuse fever (BF) is an eruptive disease and is classified as a spotted fever, which is endemic in the Mediterranean basin (i.e., Marseille fever or Mediterranean spotted fever) and the Black Sea, caused by Rickettsia conorii, with dog ticks being a vector (i.e., Rhipicephalus sanguineus). In Romania, although the first reported outbreak of BF occurred during the summer of 1931 in Constanta, the disease was discovered in 1910. Although the disease has occurred most frequently in the two counties of the Dobruja region (Constanta and Tulcea), a region of the Balkan Peninsula, during the last few years, other counties in southeastern Romania have started to report BF cases. In a period of 9 years, 533 cases were registered in Constanta county, while in a period of 11 years, 339 cases were registered in Bucharest county. In this review, we describe the bacterial tick-borne disease caused by R. conorii in southeastern Romania, focusing on its history and epidemiology, pathophysiology, clinical aspects, diagnosis, treatment and preventive measures in the context of climate changes. Although R. conorii is the principal etiologic agent of BF in southeastern Romania, we should take into consideration that other Rickettsia spp. could be present and involved in disease transmission.

Survey on tick infestation in stray dogs in localities of Malaysia

The close relationship between dogs and humans has led to concerns regarding the transmission of zoonotic pathogens through ectoparasites such as ticks. This study aimed to investigate the occurrence of ticks and the intensity on stray dogs with specific risk factors (size, sex, neutering status, body part). Additionally, identifying the predilection sites of ticks on stray dogs was crucial for developing an effective tick control program in Malaysia. A cross-sectional study was conducted among 64 stray dogs from Kelantan and Selangor States. These dogs were subjected to integumentary examinations, collecting 431 ticks comprising Rhipicephalus sanguineus s.l. “tropical lineage” and Haemaphysalis bispinosa from 53 infested dogs. The overall occurrence of tick infestation was 82.81% (53/64), with an average intensity of 8.13 ticks (range: 1–17) per stray dog. All the potential risk factors considered in this study showed no statistically significant result (P value >0.05). The head, ear, and neck were the most preferred attachment sites for ticks. These findings underscore the importance of implementing tick control programs for stray dogs, which serve as reservoirs of ticks and tick-borne pathogens for owned dogs and humans.

Morpho-molecular investigation of ectoparasitic infestation of companion animals in Sylhet city, Bangladesh

Ticks (Ixodida) and Fleas (Siphonaptera) are considered among the most important arthropod of public health concern due to their ability to transmit vector-borne pathogens to humans. By sharing a common environment, vector-borne diseases constituted major setbacks to the development of a pet population in Bangladesh. This study aimed to determine companion animal-associated ticks and fleas based on morpho-molecular approaches. Between December 2021 and May 2022, 74 animals (62 cats and 12 dogs) were examined, of which 17 (27.4%) cats and 9 (75.0%) dogs had ectoparasitic infestations, with 35.1% overall prevalence. Morphometrical examination showed the ectoparasites in these animals were Ctenocephalides spp. (flea) and Riphicephalus spp. (tick). Genetic analysis using the mitochondrial markers i.e. Cytochrome c oxidase subunit 1 (cox1) revealed the presence of two flea species i.e., Ctenocephalides canis, Ctenocephalides felis, and one tick species Rhipicephalus sanguineus. Interviews of animal owners indicate that 35.14% of them had no concern about ectoparasitic infestation or ectoparasites-borne diseases. Our results indicated that fleas and ticks were the most common ectoparasites in companion animals of this area. The zoonotic nature of some ectoparasites can be regarded as a public health alert. The findings will assist epidemiologists and policymakers in offering customized guidance for upcoming monitoring and preventive tactics in this area.

Endogenous Viral Elements in Ixodid Tick Genomes.

The documentation of endogenous viral elements (EVEs; virus-derived genetic material integrated into the genome of a nonviral host) has offered insights into how arthropods respond to viral infection via RNA interference pathways. Small non-coding RNAs derived from EVE loci serve to direct RNAi pathways in limiting replication and infection from cognate viruses, thus benefiting the host's fitness and, potentially, vectorial capacity. Here we use informatic approaches to analyze nine available genome sequences of hard ticks (Acari: Ixodidae; Rhipicephalus sanguineus, R. microplus, R. annulatus, Ixodes ricinus, I. persulcatus, I. scapularis, Hyalomma asiaticum, Haemaphysalis longicornis, and Dermacentor silvarum) to identify endogenous viral elements and to illustrate the shared ancestry of all elements identified. Our results highlight a broad diversity of viral taxa as having given rise to 1234 identified EVEs in ticks, with Mononegavirales (specifically Rhabdoviridae) well-represented in this subset of hard ticks. Further investigation revealed extensive adintovirus integrations in several Ixodes species, the prevalence of Bunyavirales EVEs (notably not observed in mosquitoes), and the presence of several elements similar to known emerging human and veterinary pathogens. These results will inform subsequent work on current and past associations with tick species with regard to the viruses from which their "viral fossils" are derived and may serve as a reference for quality control of various tick-omics data that may suffer from misidentification of EVEs as viral genetic material.

Molecular Survey of Hepatozoon canis Infection in Domestic Dogs from Sardinia, Italy.

Tick-borne protozoans of the genus Hepatozoon have been associated with infections of domestic and wild animals over the world. The occurrence of these apicomplexan agents in Sardinia has been poorly explored so far. In this study, the occurrence of Hepatozoon spp. has been investigated in domestic dogs from nine cities of Sardinia, Italy. Blood samples from each dog were collected and tested molecularly for the presence of Hepatozoon and Babesia/Theileria DNAs. Out of fifty-one dogs, nine were positive for Hepatozoon species based on the molecular detection of the parasite in blood samples. The phylogenetic relationships of strains detected here were also established. The PCR for amplification of the 18S rRNA fragment gene of Babesia/Theileria spp. did not give amplicons in any of the analyzed samples. Our results report the first molecular confirmation of Hepatozoon canis in Sardinian pet dogs and contribute to better understand the presence of these protozoans on the island. This study highlights the importance of recognizing and predicting the risk levels for the canine population, thus increasing the development of specific control measures. Also, since the distribution of hepatozoonosis is closely related to that of the definitive tick host, Rhipicephalus sanguineus, more accurate studies on Rhipicephalus ticks will be needed due to increasing the epidemiological knowledge of Hepatozoon species on the island.