Molecular detection and phylogeny of Anaplasma spp. closely related to Anaplasma phagocytophilum in small ruminants from China

Molecular Detection and Phylogenetic Analysis of Anaplasma phagocytophilum and Related Strains in Cattle from Henan, China

Anaplasma phagocytophilum is a zoonotic pathogen transmitted by arthropod vectors. The pathogen infects various vertebrate hosts, causing mild to severe illness. Molecular studies have demonstrated that A. phagocytophilum exhibits a high level of genetic diversity, with two A. phagocytophilum-related variants identified in several countries. This study represents the first application of PCR amplification and restriction fragment length polymorphism (PCR-RFLP) in conjunction with DNA sequencing to investigate the frequency and phylogenetic relationships of A. phagocytophilum and its related strains in cattle from China. A total of 662 bovine blood samples were collected from diverse regions within Henan Province, China, and pathogen DNA was detected in 75 samples, comprising 11.33% of the total. PCR-RFLP analysis identified three strains with frequency rates of 2.87% (19/662) for A. phagocytophilum, 11.33% (75/662) for A. phagocytophilum-like 1, and 3.22% (22/662) for A. phagocytophilum-like 2. Additionally, co-infections involving A. phagocytophilum and A. phagocytophilum-like 1 were observed as well as between A. phagocytophilum-like 1 and A. phagocytophilum-like 2. Anaplasma phagocytophilum-like strains 1 and 2 should be considered when diagnosing bovine anaplasmosis. Despite recent molecular studies of A. phagocytophilum-related strains, there remains a shortage of data concerning vector capability, the epidemiology of the disease, clinical signs, and genetic diversity of the pathogens. Thus, large-scale investigations involving animals and tick vectors are necessary to obtain more detailed information concerning the etiology of anaplasmosis.

Prevalence and genetic diversity of Anaplasma and Ehrlichia in ticks and domesticated animals in Suizhou County, Hubei Province, China

Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause anaplasmoses and ehrlichioses in humans and animals. In this study, we examined the prevalence of Anaplasma and Ehrlichia species in ticks and domesticated animals in Suizhou County, Hubei Province in the central China. We used PCR amplification and DNA sequencing of the 16S rRNA, groEL, and gltA genes to analyze. We collected 1900 ticks, including 1981 Haemaphysalis longicornis and 9 Rhipicephalus microplus, 159 blood samples of goats (n = 152), cattle (n = 4), and dogs (n = 3) from May to August of 2023. PCR products demonstrated that Anaplasma bovis, Anaplasma capra, and an Ehrlichia species were detected in the H. longicornis with the minimum infection rates (MIR) of 1.11%, 1.32%, and 0.05%, respectively; A. bovis, A. capra, and unnamed Anaplasma sp. were detected in goats with an infection rate of 26.31%, 1.31% and 1.97%, respectively. Anaplasma and Ehrlichia species were not detected from cattle, dogs and R. microplus ticks. The genetic differences in the groEL gene sequences of the Anaplasma in the current study were large, whereas the 16S rRNA and gltA gene sequences were less disparate. This study shows that ticks and goats in Suizhou County, Hubei Province carry multiple Anaplasma species and an Ehrlichia species, with relatively higher infection rate of A. bovis in goats. Our study indicates that multiple Anaplasma and Ehrlichia species exist in ticks and goats in the central China with potential to cause human infection.

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.

Molecular investigation of Anaplasma phagocytophilum and related strains among sheep flocks from different parts of Türkiye; with a note of phylogenetic analyses of Anaplasma phagocytophilum- like 1

Anaplasma phagocytophilum is a vector-borne zoonotic pathogen and can infect various vertebrate hosts, especially cattle, sheep, goats, horses, and dogs. Molecular-based studies have revealed that the agent has a high genetic diversity and closely related strains circulate in hosts. In this study, 618 sheep blood samples obtained from different geographic regions of Türkiye were researched for A.phagocytophilum and related strains with PCR, RFLP, and DNA sequence analyses. The DNA of these pathogens was detected in 110 (17.79%) samples. RFLP assay showed that all positive samples were infected with A.phagocytophilum-like 1, whereas A.phagocytophilum-like 2 and A.phagocytophilum were not detected. Partial parts of 16 S rRNA gene of seven randomly selected positive samples were sequenced. The phylogenetic analyses of these isolates revealed that at least two A.phagocytophilum-like 1 isolates circulate among hosts in Türkiye and around the world. A.phagocytophilum-related strains have been reported in molecular-based studies over the last few years, but there is a lack of data on the vector competence, epidemiology, clinical symptoms, and genetic diversity of these pathogens. Therefore, large-scale molecular studies are still needed to obtain detailed data on the above-mentioned topics.

Species-level microbiota of ticks and fleas from Marmota himalayana in the Qinghai-Tibet Plateau

Introduction

Ticks and fleas, as blood-sucking arthropods, carry and transmit various zoonotic diseases. In the natural plague foci of China, monitoring of Yersinia pestis has been continuously conducted in Marmota himalayana and other host animals, whereas other pathogens carried by vectors are rarely concerned in the Qinghai-Tibet Plateau.

Methods

In this study, we investigated the microbiota of ticks and fleas sampling from M. himalayana in the Qinghai-Tibet Plateau, China by metataxonomics combined with metagenomic methods.

Results

By metataxonomic approach based on full-length 16S rDNA amplicon sequencing and operational phylogenetic unit (OPU) analyses, we described the microbiota community of ticks and fleas at the species level, annotated 1,250 OPUs in ticks, including 556 known species and 492 potentially new species, accounting for 48.50% and 41.71% of the total reads in ticks, respectively. A total of 689 OPUs were detected in fleas, consisting of 277 known species (40.62% of the total reads in fleas) and 294 potentially new species (56.88%). At the dominant species categories, we detected the Anaplasma phagocytophilum (OPU 421) and potentially pathogenic new species of Wolbachia, Ehrlichia, Rickettsia, and Bartonella. Using shotgun sequencing, we obtained 10 metagenomic assembled genomes (MAGs) from vector samples, including a known species (Providencia heimbachae DFT2), and six new species affliated to four known genera, i.e., Wolbachia, Mumia, Bartonella, and Anaplasma. By the phylogenetic analyses based on full-length 16S rRNA genes and core genes, we identified that ticks harbored pathogenic A. phagocytophilum. Moreover, these potentially pathogenic novel species were more closely related to Ehrlichia muris, Ehrlichia muris subsp. eauclairensis, Bartonella rochalimae, and Rickettsia limoniae, respectively. The OPU 422 Ehrlichia sp1 was most related to Ehrlichia muris and Ehrlichia muris subsp. eauclairensis. The OPU 230 Bartonella sp1 and Bartonella spp. (DTF8 and DTF9) was clustered with Bartonella rochalimae. The OPU 427 Rickettsia sp1 was clustered with Rickettsia limoniae.

Discussion

The findings of the study have advanced our understanding of the potential pathogen groups of vectors in marmot (Marmota himalayana) in the Qinghai-Tibet Plateau.

Molecular survey of Anaplasma phagocytophilum and related variants in water buffaloes: The first detection of Anaplasma phagocytophilum-like 1

Anaplasma phagocytophilum infects various hosts and lead to mild to severe infection. Currently, two A.phagocytophilum-related variants have been documented in different countries. Although limited, there are studies revealing the presence of A.phagocytophilum in water buffaloes, but no study investigating A.phagocytophilum-like 1 and -like 2. A.phagocytophilum and related variants were investigated using PCR, PCR-RFLP, and DNA sequence analysis in water buffaloes in Türkiye. 364 buffalo blood samples were examined for A.phagocytophilum and related strains. Seven buffaloes were determined to be positive with PCR and PCR-RFLP revealed that all samples were A.phagocytophilum-like 1. According to the partial sequence of 16 S rRNA gene, A.phagocytophilum like-1 may split into two different variants. This work supplies the first molecular report of A.phagocytophilum-like 1 in water buffaloes. However, a lack of information is present on the pathogen's clinical manifestations and vector species. There is still a need to investigate vectors and clinical signs of the pathogen.

Serological Analysis of IgG and IgM Antibodies against Anaplasma spp. in Various Animal Species of the Qinghai-Tibetan Plateau

Anaplasma genus infects the blood cells of humans and animals by biting, causing zoonotic anaplasmosis. However, limited data are available on carrier animals for Anaplasma spp. antibodies in the Qinghai−Tibetan Plateau Area. Therefore, a serological indirect ELISA diagnostic method based on the major surface protein 5 (MSP5), derived from Anaplasma phagocytophilum, was developed in this study to analyze both IgG and IgM antibodies of Anaplasma spp. in a total of 3952 animals from the Qinghai−Tibetan Plateau, including yaks (Bos grunniens), cows (Bos taurus), cattle (Bos taurus domesticus), Tibetan sheep (Ovis aries), horses (Equus ferus caballus), pigs (Sus domesticus), chickens (Gallus gallus domesticus), donkeys (Equus asinus), stray dogs (Canis sp.), and stray cats (Felis sp.). The results showed that recombinant MSP5 protein was expressed and was successfully used to establish the indirect ELISA methods. The overall positivity for Anaplasma IgG and IgM antibodies was 14.6% (578/3952) and 7.9% (312/3952), respectively, and a total of 123 animals (3.1%) were both IgG- and IgM-positive. Moreover, the most prevalent Anaplasma IgG positivity was exhibited by donkeys (82.5%), followed by stray dogs, Tibetan sheep, pigs, chickens, horses, yaks, cows, cattle, and stray cats. The analysis for IgM antibody positivity revealed that IgM positivity was the most prevalent in the stray dogs (30.1%), followed by horses, yaks, Tibetan sheep, cows, stray cats, and cattle. Moreover, the results revealed significant differences (p < 0.05) at different altitudes in Anaplasma-specific IgG in the yaks, Tibetan sheep, and horses, and in IgM in the yaks and Tibetan sheep. In conclusion, this study is the first to demonstrate that yaks, cows, cattle, Tibetan sheep, horses, donkeys, stray dogs, stray cats, pigs, and chickens living in the Qinghai−Tibet Plateau are carrier animals for Anaplasma spp. IgG or IgM antibodies. The current findings provide valuable current data on the seroepidemiology of anaplasmosis in China and for plateau areas of the world.