Prevalence of Theileria in cattle in China: A systematic review and meta-analysis

The First Molecular Detection of Theileria luwenshuni from Haemaphysalis mageshimaensis on Orchid Island, Taiwan, with No Evidence of SFTSV

Theileriosis is considered an economically important disease that may decrease productivity and cause a high mortality rate in livestock. Only a few studies have reported Theileria spp., such as T. sergenti and T. buffeli, in recent decades in Taiwan. In the present study, 401 ticks have been collected on Orchid Island in June 2022 and April 2023. Our environmental investigation for SFTSV unintentionally discovered T. luwenshuni in Haemaphysalis mageshimaensis on Orchid Island via PCR. The PCR products were sequenced, and the detected 18S rRNA gene sequences shared a 99.65-99.93% identity with T. luwenshuni sequences from ticks and ruminants in Myanmar and China. Despite the difficulty in clarifying the source of T. luwenshuni within neighboring regions, our findings provide an updated distribution of T. luwenshuni in Asia. This is not only the first time that T. luwenshuni was found in H. mageshimaensis but also the first report of T. luwenshuni on Orchid Island, Taiwan. Our study indicates that ruminants may be at risk of infection. Therefore, further investigations are needed to determine the distribution of T. luwenshuni among ruminants on Orchid Island and in Taiwan.

Investigation of Babesia spp. and Theileria spp. in ticks from Western China and identification of a novel genotype of Babesia caballi

Babesia spp. and Theileria spp. are tick-borne protozoan parasites with veterinary importance. In China, epidemiological and genetic investigations on many Babesia and Theileria species were still absent in many areas and many tick species. From Aug 2021 to May 2023, 645 ticks were collected from the body surface of domestic animals (camels, goats, sheep, and cattle) using tweezers in seven counties in three provinces including Xinjiang (Qitai, Mulei, Hutubi, and Shihezi counties), Chongqing (Youyang and Yunyang counties), and Qinghai (Huangzhong county). Three tick species were morphologically and molecularly identified (334 Hyalomma asiaticum from Xinjiang, 245 Rhipicephalus microplus from Chongqing, and 66 Haemaphysalis qinghaiensis from Qinghai). A total of three Babesia species and two Theileria species were detected targeting the 18S gene. The COI and cytb sequences were also recovered from Babesia strains for further identification. In R. microplus from Chongqing, Babesia bigemina, the agent of bovine babesiosis, was detected. Notably, in H. asiaticum ticks from Xinjiang, a putative novel genotype of Babesia caballi was identified (0.90%, 3/334), whose COI and cytb genes have as low as 85.82% and 90.64-90.91% nucleotide identities to currently available sequences. It is noteworthy whether the sequence differences of its cytb contribute to the drug resistance of this variant due to the involvement of cytb in the drug resistance of Babesia. In addition, Theileria orientalis and Theileria annulata were detected in R. microplus from Chongqing (12.20%, 31/245) and H. asiaticum from Xinjiang (1.50%, 5/334), respectively. These results suggest that these protozoan parasites may be circulating in domestic animals in these areas. The pathogenicity of the novel genotype of B. caballi also warrants further investigation.

Establishment and application of TaqMan real-time PCR method for detection of Theileria annulata resistant to buparvaquone

Tropical theileriosis is a tick-borne disease that caused by Theileria annulata, and leads to substantial economic impact in endemic area. Distinguishes to other piroplasms, Theileria is the only eukaryotic parasite could transform mammalian leukocytes. At present, buparvaquone is the most effective drug used for treatment of Theileria infection. However, frequently reported of failure treatment with buparvaquone for some T. annulata isolates. Mutation of TaPIN1 was reported to be the direct reason for failure of buparvaquone treatment. Through in vitro culture, a T. annulata isolate with a TaPIN1 mutation that is similar to the reported strain was recently identified in China. In order to understand the distribution of Theileria with mutation of TaPIN1 in China, here we developed a TaqMan probe-based real-time PCR technology to detect the mutated TaPIN1 gene. The specificity, sensitivity and reproducibility of the established TaqMan Real-time PCR method were evaluated, and field cattle blood samples collected from Xinjiang Uyghur Autonomous Region were used to test its application. Among 1683 samples, 335 samples were confirmed positive for T. annulata by traditional PCR method and 34 samples were positive for buparvaquone-resistant. The TaPIN1 gene of those 34 samples was sequenced and analyzed with the published gene sequences from NCBI database. The results showed that the sequence obtained from the present study has good consistency with those published sequences. In conclusion, the TaqMan probe-based real-time PCR targeting T. annulata mutated TaPIN1 gene was successfully established and can be used to detect clinical samples to investigation of buparvaquone-resistant parasites in Xinjiang region quickly and accurately, which will be useful for guiding clinical medicine application.

Current status of ruminant anaplasmosis in Algeria: a systematic review and meta-analysis

Anaplasmosis is an emerging infectious disease that is being recognised all over the world, with impact on animal health.This systematic review and meta-analysis aimed to assess the rate infection of Anaplasma spp. infection in Algerian ruminants. Three databases were searched to identify eligible studies for the final systematic review and meta-analysis. The 'meta' package in the R software was used for the meta-analysis, and the random effects model was chosen to pool the data. Meta-analysis encompasses 14 research papers spanning 19 years (2004-2023), out of an initial pool of 737 articles retrieved from various databases. The study included a total of 1515 cattle, 190 sheep, and 310 goats, and the overall Anaplasma infection rate was estimated at 28% (95% CI, 17-41%). The analysis revealed varying infection rates among species, with cattle at 20%, sheep at 30%, and goats at 61%. Five classified species and two unclassified strains belonging to Anaplasma genus were identified in ruminants, which are A. marginale, A. centrale, A. bovis, A. ovis, A. phagocytophilum, A. phagocytophilum-like strains, and A. platys-like strains. Among these, A. marginale was prevalent in ten out of eleven cattle studies. The data also revealed regional variations, with Northeastern Algeria showing a higher infection rate (26%) compared to North-central Algeria (9%). In the subgroup analysis, clinically healthy cattle had a higher infection rate (28%) compared to suspected disease cattle (16%). Molecular biology screening methods yielded a significantly higher infection rate (33%) than microscopy (12%). Gender analysis suggested slightly higher infection rates among male cattle (19%) compared to females (16%). Age analysis indicated that Anaplasma infection was more common in cattle less than 12 months (14%) compared to those over 12 months (9%). This systematic review provides valuable insights, highlighting the need for continued surveillance and potential preventive strategies in different regions and among different animal populations in Algeria.

Potential novel Colpodella spp. (phylum Apicomplexa) and high prevalence of Colpodella spp. in goat-attached Haemaphysalis longicornis ticks in Shandong province, China

Tick-borne Apicomplexan parasites pose a significant threat to both public health and animal husbandry. Identifying potential pathogenic parasites and gathering their epidemiological data are essential for prospectively preventing and controlling infections. In the present study, genomic DNA of ticks collected from two goat flocks (Goatflock1 and Goatflock2) and one dog group (Doggroup) were extracted and the 18S rRNA gene of Babesia/Theileria/Colpodella spp. was amplified by PCR and sequenced. Phylogenetic analysis was conducted based on the obtained sequences. The differences in pathogen positive rates between ticks of different groups were statistically analyzed using the Chi-square or continuity-adjusted Chi-square test. As a result, two pathogenic Theileria (T.) luwenshuni genotypes, one novel pathogenic Colpodella sp. HLJ genotype, and two potential novel Colpodella spp. (referred to as Colpodella sp. struthionis and Colpodella sp. yiyuansis in this study) were identified in the Haemaphysalis (H.) longicornis ticks. Ticks of Goatflock2 had a significantly higher positive rate of Colpodella spp. than those from Goatflock1 (χ2=92.10; P = 8.2 × 10-22) and Doggroup (χ2=42.34; P = 7.7 × 10-11), and a significantly higher positive rate of T. luwenshuni than Doggroup (χ2=5.38; P = 0.02). However, the positive rates of T. luwenshuni between Goatflock1 and Goatflock2 were not significantly different (χ2=2.02; P = 0.16), and so as the positive rates of both pathogens between Goatflock1 and Doggroup groups (P > 0.05). For either Colpodella spp. or T. luwenshuni, no significant difference was found in prevalence between male and female ticks. These findings underscore the potential importance of Colpodella spp. in domestic animal-attached ticks, as our study revealed two novel Colpodella spp. and identified Colpodella spp. in H. longicornis for the first time. The study also sheds light on goats' potential roles in the transmission of Colpodella spp. to ticks and provides crucial epidemiological data of pathogenic Theileria and Colpodella. These data may help physicians, veterinarians, and public health officers prepare suitable detection and treatment methods and develop prevention and control strategies.

Systematic Review and Meta-Analysis on Piroplasma spp. Infection and Co-infection with Anaplasma marginale in Domestic Ruminants from Algeria

BACKGROUND

Piroplasmosis and anaplasmosis stand out as the primary diseases affecting livestock during periods of tick activity. These vector-borne diseases continue to emerge worldwide, exerting a detrimental impact on both animal health and national economies. The purpose of this study is to assess the prevalence of Piroplasma spp. and its co-occurrence with Anaplasma marginale in domestic ruminants in Algeria.

METHODS

Three databases were systematically reviewed to identify eligible studies for the final meta-analysis, following the PRISMA statement. The 'meta' package in the R software was employed for the meta-analysis with the random effects model chosen for data pooling.

RESULTS

The meta-analysis encompasses 14 research papers spanning a 19-year period (2004-2023). Theileria spp. was identified in all studies, covering 1675 cattle, 190 sheep, and 128 goats, yielding an overall Theileria infection rate of 45% (95% CI 26-65%). Specifically, cattle had a 59% infection rate, while sheep and goats had rates of 18% and 20%, respectively. Babesia spp. was found in nine studies, involving 1183 cattle and 190 sheep, resulting in an overall Babesia infection rate of 7% (95% CI 4-15%), with cattle and sheep having rates of 10% and 3%, respectively. Notably, eight Piroplasma species T. annulata, T. orientalis, T. buffeli, T. equi, Theileria sp., B. bovis, B. bigemina, and B. occultans were detected in cattle, with T. annulata being the most prevalent at 54%. Regional disparities and host factors also impacted infection rates, with higher rates in Northeastern Algeria and among suspected disease cattle. Additionally, gender, age, and breed influenced cattle susceptibility to Theileria infection. Furthermore, six distinct co-infections between Piroplasma spp. and A. marginale were observed, with T. annulata/A. marginale identified in six studies, demonstrating an 8.3% co-infection rate.

CONCLUSION

This analysis offers crucial insights into the current status of Piroplasmosis and its co-infection with A. marginale in Algerian domestic ruminants, providing valuable data for surveillance and prevention strategies.

Molecular Detection and Genotyping of Theileria spp. in Deer (Cervidae) in Korea

Major clinical symptoms of Theileria infection include fever, anemia, anorexia, jaundice, and decreased milk production. Although several studies have been conducted on tick-borne pathogens, including Theileria in Korea, only a few have focused on Theileria infection in deer, including the Korean water deer. Blood samples from 160 deer were collected and subjected to DNA extraction and polymerase chain reaction (PCR). Next, PCR-positive samples were sequenced and analyzed by constructing a phylogenetic tree. The results showed that the overall infection rate of Theileria was 8.1% (13/160). Infection rates of 100% were observed in the northern and southern regions. However, the study's limitation was its small sample size, wherein five and one samples were analyzed from the northern and southern regions, respectively. The central region exhibited the lowest infection rate of 2.9% (4/140). Infection rates also differed based on seasons, with the highest (18.4%, 9/49) being observed in spring, followed by that in summer (8.9%, 4/45). However, no infection was observed during autumn and winter. A phylogenetic analysis indicated that the PCR-positive samples contained Theileria luwenshuni, which usually infects small ruminants, such as goats and sheep.

Preliminary study on prevalence of hemoprotozoan parasites harbored by Stomoxys (Diptera: Muscidae) and tabanid flies (Diptera: Tabanidae) in horse farms in Nakhon Si Thammarat province, Southern Thailand

Background and Aim

Stomoxys and tabanid flies are of medical and veterinary importance because they play crucial roles in disease transmission as mechanical vectors of various hemopathogens. However, its role as a hemoprotozoan parasite vector in horse farms has not been studied. Therefore, we investigated the occurrence of hemoprotozoan parasites belonging to the genera Babesia, Theileria, and Trypanosoma in Stomoxys and tabanid flies using conventional polymerase chain reaction (PCR) and DNA sequencing.

Materials and Methods

All samples (Stomoxys and tabanid flies) were collected using an Nzi trap for three consecutive days each month from November 2022 to March 2023. The flies were morphologically identified to the species level and separated according to sex. Individual (for tabanid flies) or pooled samples (consisting of three specimens of Stomoxys flies of the same species and sex collected from the same site) were used for DNA extraction. Conventional PCR was used to screen for hemoprotozoan parasite DNA, followed by Sanger sequencing to identify the species.

Results

In total, 189 biting flies were collected, including four species of Stomoxys (Stomoxys bengalensis, Stomoxys calcitrans, Stomoxys indicus, and Stomoxys sitiens) and five species of tabanids (Atylotus cryptotaxis, Chrysops dispar, Tabanus megalops, Tabanus mesogaeus, and Tabanus rubidus). Stomoxys calcitrans was the most prevalent species, accounting for 58.7% (n = 111) of the collected flies. Ten (12.4%) of the 81 samples (individuals and pools) analyzed by PCR were positive for the 18S rRNA gene of the Theileria/Babesia species. Trypanosoma DNA was not detected in any sample. After performing Basic Local Alignment Search Tool searches and a phylogenetic analysis, only six samples (7.4%), including S. calcitrans (n = 2), S. sitiens (n = 2), T. megalops (n = 1), and A. cryptotaxis (n = 1), were found to be infected with Theileria sinensis. Furthermore, apicomplexan parasites, namely, Mattesia spp. and Colpodella spp., were found on S. indicus, the fungus Meira spp. was found on S. calcitrans, and the pathogenic green alga Helicosporidium spp. was found on A. cryptotaxis.

Conclusion

This study is the first to report a variety of Stomoxys and tabanid flies collected from horse farms in Thailand, which were found to be infected with Theileria and Colpodella species that affect mammals, suggesting that Stomoxys and tabanid flies can be used to confirm the presence of hemoprotozoan parasites in the study area. Understanding the presence of hemoprotozoa in flies could help design vector control programs and manage various diseases in the study area.

18S rRNA Gene-Based Piroplasmid PCR: An Assay for Rapid and Precise Molecular Screening of Theileria and Babesia Species in Animals

PURPOSE

The parasites of genera such as Babesia and Theileria are called piroplasmids due to the pear-shaped morphology of the multiplying parasite stages in the blood of the vertebrate host. Because of the enormous number of parasite species and the challenges of multiplex PCR, initial screening of samples using piroplasmid-specific PCR may be a more cost-effective and efficient technique to identify parasite species, especially during epidemiological studies. Accordingly, 18S rRNA PCR was standardized and optimized on common piroplasmids of different animals like cattle, buffaloes, sheep, goats, dogs, horses, and leopards.

METHODS

Bloods samples from 1250 animals were collected from different animals in Junagadh district of Gujarat, India. 18S rRNA PCR was standardized and optimized as a primary method for molecular screening of piroplasms in domestic and wild animals. The method was checked for its analytical sensitivity and specificity. Parasite species-specific PCR and sequencing was used to validate the test. Moreover, in-silico restriction enzyme (RE) analysis was also done to assess its applicability in PCR-RFLP.

RESULTS

Piroplasm infections were recorded in 63.3% of animals in Junagadh. The 18S rRNA PCR detected the piroplasmid DNA in as low as 39 picograms (pg) of whole blood genomic DNA isolated from microscopically Theileria positive blood samples and no reactivity was recorded from common but unrelated haemoparasites viz., Trypanosoma evansi, Hepatozoon spp., Anaplasma spp., and Ehrlichia canis was observed. The 18S rRNA PCR assay findings were confirmed by species-specific PCR and sequencing. Analysis of different sequences generated using 18S rRNA PCR revealed that the amplicon size of Babesia spp. is nearly 400 bp (393-408 bp) whereas Theileria spp. were more than 400 bp (418-424 bp). The percentage of sequence divergence among Babesia and Theileria spp. was 7.3-12.2% and 0.7-12.2%, respectively. In-silico restriction enzyme (RE) analysis reveals the presence of at least one site for a commercially available RE in 18S rRNA fragments of every parasite, which can differentiate it from its congeners.

CONCLUSIONS

The presented universal oligonucleotide-based PCR assay provides a highly sensitive, specific, cost-effective, and rapid diagnostic tool for the initial screening of piroplasmids infecting domestic and wild animals and is potentially helpful for large-scale epidemiological studies.

18S rRNA Gene-Based Piroplasmid PCR: An Assay for Rapid and Precise Molecular Screening of Theileria and Babesia Species in Animals

Purpose

The parasites of genera such as Babesia and Theileria are called piroplasmids due to the pear-shaped morphology of the multiplying parasite stages in the blood of the vertebrate host. Because of the enormous number of parasite species and the challenges of multiplex PCR, initial screening of samples using piroplasmid-specific PCR may be a more cost-effective and efficient technique to identify parasite species, especially during epidemiological studies. Accordingly, 18S rRNA PCR was standardized and optimized on common piroplasmids of different animals like cattle, buffaloes, sheep, goats, dogs, horses, and leopards.

Methods

Bloods samples from 1250 animals were collected from different animals in Junagadh district of Gujarat, India. 18S rRNA PCR was standardized and optimized as a primary method for molecular screening of piroplasms in domestic and wild animals. The method was checked for its analytical sensitivity and specificity. Parasite species-specific PCR and sequencing was used to validate the test. Moreover, in-silico restriction enzyme (RE) analysis was also done to assess its applicability in PCR–RFLP.

Results

Piroplasm infections were recorded in 63.3% of animals in Junagadh. The 18S rRNA PCR detected the piroplasmid DNA in as low as 39 picograms (pg) of whole blood genomic DNA isolated from microscopically Theileria positive blood samples and no reactivity was recorded from common but unrelated haemoparasites viz., Trypanosoma evansi, Hepatozoon spp., Anaplasma spp., and Ehrlichia canis was observed. The 18S rRNA PCR assay findings were confirmed by species-specific PCR and sequencing. Analysis of different sequences generated using 18S rRNA PCR revealed that the amplicon size of Babesia spp. is nearly 400 bp (393–408 bp) whereas Theileria spp. were more than 400 bp (418–424 bp). The percentage of sequence divergence among Babesia and Theileria spp. was 7.3–12.2% and 0.7–12.2%, respectively. In-silico restriction enzyme (RE) analysis reveals the presence of at least one site for a commercially available RE in 18S rRNA fragments of every parasite, which can differentiate it from its congeners.

Conclusions

The presented universal oligonucleotide-based PCR assay provides a highly sensitive, specific, cost-effective, and rapid diagnostic tool for the initial screening of piroplasmids infecting domestic and wild animals and is potentially helpful for large-scale epidemiological studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11686-022-00625-2.