Molecular Characterization of Bartonella Species Discovered in Ectoparasites Collected from Domestic Animals, Cuzco, Peru

Identification and Characterization of Ectoparasite-Borne Pathogens Through Vector and Animal Surveillance in Andean Countries, South America

Infectious diseases transmitted by ectoparasites such as fleas, lice, mites, and ticks constitute a global public health problem. Tick-borne diseases are the most widely studied emerging ectoparasite-borne diseases (EBD) mainly due to their increasing incidence worldwide, including in South America. Furthermore, in Peru and neighboring Andean countries (Bolivia, Colombia, and Ecuador), surveillance reports indicate that Rickettsia species appear to be the most diverse and widely distributed ectoparasite-borne pathogens (EBP) followed by Babesia species, and with fewer species of Anaplasma, Bartonella, Borrelia, Ehrlichia, Coxiella, and Phlebovirus pathogens. Amblyomma, Dermacentor, Rhipicephalus, and Ixodes ticks were reported as the most predominant ectoparasites found infected with a diversity of EBP belonging to Rickettsia, Babesia, Anaplasma, Bartonella, and Ehrlichia species. Overall, people living in rural areas where agriculture and livestock production are their main economic means are at higher risk of EBD.

First metagenomic sequencing for the analysis of microbial community populations of adults and pupae of Melophagus ovinus in Xinjiang, China

Introduction

Melophagus ovinus, a parasite on the body surface of sheep, directly attacks the host through biting and sucking blood and may also transmit pathogens in the process. There are currently only a few studies on the microbial composition of M. ovinus, while there are no such studies on pupae.

Methods

In this study, samples AT-1 to AT-4 each contained four M. ovinus individuals, while sample AT-5 comprised four M. ovinus pupae, all used for metagenomic sequencing and analysis. Melophagus ovinus adults and pupae were collected from four regions in Xinjiang, China. DNA was extracted from the samples, amplified, and sequenced using the Illumina Novaseq 6000 System; finally, the sequencing data were analyzed using molecular biology software.

Results and discussion

From all samples, a total of 32 phyla, comprising 372 genera and 1,037 species, were detected. The highest microbial diversity was observed in Kuqa City (AT-2) and Qira County (AT-4). Pupae exhibited 40 unique microbial genera (AT-5) but did not have the highest microbial diversity. Proteobacteria was the dominant phylum in all samples. The dominant genera included Bartonella, Wolbachia, Pseudomonas, and Arsenophonus. This is the first study to report most of the bacteria (e.g., Pseudomonas versuta and Arsenophonus nasoniae), fungi (e.g., Saitoella complicata), viruses (e.g., Orf virus and Wolbachia phage WO), and protozoa (e.g., Trypanosoma theileri and Babesia bigemina) in M. ovinus. This study has enriched the microbial diversity data of M. ovinus, and the pathogens it carries may pose a threat to public health safety and the economy of related industries, necessitating further research to develop effective biological control strategies.

Eutrichophilus cordiceps Mjöberg, 1910 (Ischnocera: Trichodectidae) in Spiny Tree Porcupines (Coendou villosus): New locality records and the first molecular evidence of association with Bartonella sp

The chewing louse genus Eutrichophilus Mjöberg has 19 species only associated with porcupines (Rodentia: Erethizontidae). Of these species, E. cercolabes, E. cordiceps, E. emersoni, E. minor, E. moojeni, and E. paraguayensis have been recorded in Brazil. In the present study, we report E. cordiceps for the first time in the São Paulo State (Bauru Municipality) and for the second time in the Santa Catarina State (Lages Municipality), providing scanning electron images and light microscopy for the eggs, as well as the first molecular data (18S rRNA) for the genus. Additionally, Bartonella sp. was detected for the first time in this chewing lice species.

Molecular detection of hemotropic Mycoplasma and Bartonella species in lice from sheep and goats of Mexico

The knowledge of lice associated with small ruminants, especially sheep and goats, is scarce. In Mexico, there are historical reports of six species of chewing and sucking lice associated with Capra hircus and Ovis canadensis. However, the reports did not analyze the ecology of the infestations or the presence of potentially pathogenic bacteria. For this reason, the objectives of this study were i) to identify the species of lice associated with sheep and goats in three states of the Mexican Republic, ii) to characterize the infestations, and iii) to identify the presence of bacterial pathogens. From October 2019 to August 2021, six ranches with sheep and goats were sampled in the states of Hidalgo and Veracruz. Hosts were visually inspected, and lice were retrieved with forceps. The specimens were sexed and identified using morphological taxonomic keys. DNA extraction was performed individually, and a fragment of the cytochrome oxidase subunit 1 gene (COI) was amplified for the molecular identification of the specimens. Subsequently, Anaplasma, Bartonella, Ehrlichia, Mycoplasma, and Rickettsia were molecularly detected. Additionally, the infestations were characterized by calculating the prevalence and mean abundances. We collected 563 specimens of three species, Bovicola caprae, Bovicola ovis, and Linognathus africanus. The highest infestation levels were recorded for B. ovis (66.7%; 4.4) from Veracruz. Additionally, two Bartonella species were detected: Bartonella mellophagi in B. ovis and Bartonella capreoli in L. africanus. In contrast, Mycoplasma ovis was detected exclusively in one pool of B. ovis. This study provides new bacterial-ectoparasite associations and highlights the possible role of these neglected ectoparasites as vectors in the populations of sheep and goats from Mexico.

Bartonella Species in Cambodia, Ghana, Laos, and Peru: Results from Vector and Serosurveys

Background: Bartonella species are fastidious gram-negative vector-borne bacteria with a wide range of mammalian reservoirs. While it is understood that some species of Bartonella are human pathogens, the extent of human exposure to Bartonella species (both pathogenic and nonpathogenic) is yet to be fully understood. Materials and Methods: To this end, residual sera from participants enrolled in undifferentiated fever studies in Cambodia, Ghana, Laos, and Peru were screened for the presence of IgG antibodies against Bartonella quintana and Bartonella henselae, using the FOCUS diagnostics Dual Spot- Bartonella IgG Immunofluorescence assay. Forty-eight patients with suspected or confirmed Bartonella bacilliformis exposure or infection in Peru were screened to assess cross-reactivity of the FOCUS assay for IgG against other Bartonella species. Results: Ten of 13 patients with confirmed B. bacilliformis infection were Bartonella-specific IgG positive, and overall, 36/48 of the samples were positive. In addition, 79/206, 44/200, 101/180, and 57/100 of the samples from Peru, Laos, Cambodia, and Ghana, respectively, were Bartonella-specific IgG positive. Furthermore, ectoparasite pools from Cambodia, Laos, and Peru were tested using quantitative real-time PCR (qPCR) for the presence of Bartonella DNA. Of the sand fly pools collected in Peru, 0/196 were qPCR positive; 15/140 flea pools collected in Cambodia were qPCR positive; while 0/105 ticks, 0/22 fleas, and 0/3 louse pools collected in Laos tested positive for Bartonella DNA. Conclusion: Evidence of Bartonella in fleas from Cambodia supports the possibility that humans are exposed to Bartonella through this traditional vector. However, Bartonella species were not found in fleas, ticks, or lice from Laos, or sand flies from Peru. This could account for the lower positive serology among the population in Laos and the strictly localized nature of B. bacilliformis infections in Peru. Human exposure to the Bartonella species and Bartonella as a human pathogen warrants further investigation.

First determination of DNA virus and some additional bacteria from Melophagus ovinus (sheep ked) in Tibet, China

Melophagus ovinus (sheep ked) is one of the common ectoparasites in sheep. In addition to causing direct damage to the host through biting and sucking blood, sheep ked is a potential vector of helminths, protozoa, bacteria, and viruses. Sheep M. ovinus samples from three regions in Tibet were selected for DNA extraction. The 16S rDNA V3-V4 hypervariable region was amplified, after genomic DNA fragmentation, Illumina Hiseq libraries were constructed. The 16S rRNA sequencing and viral metagenomics sequencing were separately conducted on the Illumina Novaseq 6000 platform and molecular biology software and platforms were employed to analyze the sequencing data. Illumina PE250 sequencing results demonstrated that the dominant bacteria phylum in M. ovinus from Tibet, China was Proteobacteria, where 29 bacteria genera were annotated. The dominant bacterial genera were Bartonella, Wolbachia, and Arsenophonus; Bartonella chomelii, Wolbachia spp., and Arsenophonus spp. were the dominant bacterial species in M. ovinus from Tibet, China. We also detected Kluyvera intermedia, Corynebacterium maris DSM 45190, Planomicrobium okeanokoites, and Rhodococcus erythropolis, of which the relative abundance of Kluyvera intermedia was high. Illumina Hiseq sequencing results demonstrated that 4 virus orders were detected in M. ovinus from Tibet, China, and 3 samples were annotated into 29 families, 30 families, and 28 families of viruses, respectively. Virus families related to vertebrates and insects mainly included Mimiviridae, Marseilleviridae, Poxviridae, Ascoviridae, Iridoviridae, Baculoviridae, Hytrosaviridae, Nudiviridae, Polydnaviridae, Adomaviridae, Asfarviridae, Hepeviridae, Herpesviridae, and Retroviridae; at the species level, the relative abundance of Tupanvirus_soda_lake, Klosneuvirus_KNV1, and Indivirus_ILV1 was higher. African swine fever virus and many poxviruses from the family Poxviridae were detected, albeit their relative abundance was low. The dominant bacterial phylum of M. ovinus from Tibet, China was Proteobacteria, and the dominant bacterial genera were Bartonella, Wolbachia, and Arsenophonus, where 23 out of 29 annotated bacteria genera were first reported in M. ovinus. Kluyvera intermedia, Corynebacterium maris DSM 45190, Planomicrobium okeanokoites, and Rhodococcus erythropolis were detected for the first time. All DNA viruses detected in this study have been reported in M. ovinus for the first time.