Novel Rickettsia in Ticks, Tasmania, Australia

A novel rickettsia was detected in Ixodes tasmani ticks collected from Tasmanian devils. A total of 55% were positive for the citrate synthase gene by quantitative PCR. According to current criteria for rickettsia speciation, this new rickettsia qualifies as Candidatus Rickettsia tasmanensis, named after the location of its detection

Epidemiology of Goat Nematode Infections in Different Ecological Regions of Argentina´S Northwest

The aim of this work was to study the etiology and epidemiology of gastrointestinal nematodes (GIN) of goat from the Arid valleys and canyons (AVC), Tempered valleys (TV) and the Semiarid Chaco (SC) regions of northwestern Argentina. Ten flocks were studied and 35 to 40 goats per flock (total= 420 goats) were fecal matter sampled each 30-40 days. Individual eggs per gram of faeces (epg) and faeces cultures were performed. Differences among epg were compared using Kruskal–Wallis non-parametric test. The epg of the three regions showed the same trend: an increment from February reaching the highest average epg peak in April-May and then a fall ​​towards the summer. Goat flocks of TV region showed the highest epg compared to the other two regions, which generally showed low epg values. Haemonchus sp. and Trichostrongylus spp. were the predominant nematode genera recovered in the three regions, although in a smaller proportion Teladorsagia, Oesophagostomum, Nematodirus, Trichuris, Skrjabinema and Strongyloides genera were also recovered. These results show that GIN would be a limiting factor of caprine production in the TV and only during critical periods and under some breeding systems in the other regions.Instituto de Investigación Animal del Chaco SemiáridoFil: Suarez, Victor Humberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido. Área de Investigación en Salud Animal; ArgentinaFil: Martinez, Gabriela Marcela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; ArgentinaFil: Olmos, Leandro Hipolito. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido. Área de Investigación en Salud Animal; Argentin

Effects of condensed tannins towards dairy caprine gastrointestinal nematodes

In order to evaluate condensed tannins (CT) effect on dairy goat gastrointestinal nematodes (GIN) under a grazing and confined systems, two experiments (E1 and E2) were made. On both, goats were kept in two groups of 10 animals each. Groups were: control, without treatment (CG) and CT supplemented (CTG) daily with 25 g (1,25%) in E1 and 75 g (2%) in E2. During the E1, feeding was based on Lucerne (Medicago sativa) grazing and supplementation with 500 g of corn grain and during the E2, stabled milking goats ate 500 g of corn grain and ad libitum lucerne hay. Biweekly, faecal egg counts (FEC) and coprocultures were made. In addition, FAMACHA© technique, body condition score (BCSS) and ingested food were recorded each two weeks during the 90 days (E1) and 76 (E2) days of trial. The FEC values in most of the study were low and no significant differences (p<0.78) were detected between groups. Mean FEC were 534 (CTG) and 357 (CG) during E1 and 509 (CTG) and 484 (CG) during E2. The predominant NGI genera were Trichostrongylussp. (48.1%), Haemonchus sp. (39.9%) and Teladorsagia sp. (12.0%). FAMACHA© scores did not show significant (p<0.41) differences between groups, but the CG (median=3) showed a BCS significantly (p<0.05) higher than those of CTG (median=2.5). The average milk production did not present statistically significant differences between groups (p<0.57), between sampling dates (p<0.23) and group x sampling dates (p<0.65). Under the conditions of these studies 25g or 75 g of CT in the diet had no anthelmintic or productive effects.Instituto de Investigación Animal del Chaco SemiáridoFil: Suarez, Victor Humberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido. Área de Investigación en Salud Animal; ArgentinaFil: Olmos, Leandro Hipolito. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido. Área de Investigación en Salud Animal; ArgentinaFil: Martinez, Gabriela Marcela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; ArgentinaFil: Sandoval, G.V. Universidad Católica de Salta. Facultad de Ciencias Agrarias y Veterinarias; ArgentinaFil: Alfaro, Emilio José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; ArgentinaFil: Alfaro, Rodolfo Jose. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; ArgentinaFil: Moreno, Ramiro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta. Área de Investigación en Salud Animal; Argentin

Rapid Spread of Severe Fever with Thrombocytopenia Syndrome Virus by Parthenogenetic Asian Longhorned Ticks

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A survey of ticks (Acari: Ixodidae) of companion animals in Australia

Background: Ticks are among the most important vectors of pathogens affecting companion animals, and also cause health problems such as tick paralysis, anaemia, dermatitis, and secondary infections. Twenty ixodid species have previously been recorded on dogs, cats, and horses in Australia, including Rhipicephalus sanguineus, Ixodes holocyclus and Haemaphysalis longicornis, which transmit tick-borne diseases. A survey of hard ticks (Acari: Ixodidae) was conducted during 2012-2015 to investigate tick species that infest dogs, cats, and horses in Australia. Methods: Individual tick specimens were collected from dogs, cats and horses across Australia and sample collection locations were mapped using QGIS software. Ticks were morphologically examined to determine species, instar and sex. The companion animal owners responded to questionnaires and data collected were summarised with SPSS software. Results: A total of 4765 individual ticks were identified in this study from 7/8 states and territories in Australia. Overall, 220 larvae, 805 nymphs, 1404 males, and 2336 females of 11 tick species were identified from 837 companion animal hosts. One novel host record was obtained during this study for Ixodes myrmecobii, which was found on Felis catus (domestic cat) in the town of Esperance, Western Australia. The most common tick species identified included R. sanguineus on dogs (73 %), I. holocyclus on cats (81 %) and H. longicornis on horses (60 %). Conclusions: This study is the first of its kind to be conducted in Australia and our results contribute to the understanding of the species and distribution of ticks that parasitise dogs, cats, and horses in Australia. Records of R. sanguineus outside of the recorded distribution range emphasise the need for a systematic study of the habitat range of this species. Several incomplete descriptions of ixodid species encountered in this study hindered morphological identification

J Med Entomol

The Asian longhorned tick, Haemaphysalis longicornis Neumann (Acari: Ixodidae), was recently introduced into the United States and is now established in at least 15 states. Considering its ability for parthenogenetic propagation and propensity for creating high-density populations, there is concern that this tick may become involved in transmission cycles of endemic tick-borne human pathogens. Human granulocytic anaplasmosis (HGA) caused by Anaplasma phagocytophilum is one of the more common tick-borne diseases in the United States, especially in the northeastern and midwestern states. There is considerable geographical overlap between HGA cases and the currently known distribution of H. longicornis, which creates a potential for this tick to encounter A. phagocytophilum while feeding on naturally infected vertebrate hosts. Therefore, we evaluated the ability of H. longicornis to acquire and transmit the agent of HGA under laboratory conditions and compared it to the vector competence of I. scapularis. Haemaphysalis longicornis nymphs acquired the pathogen with the bloodmeal while feeding on infected domestic goats, but transstadial transmission was inefficient and PCR-positive adult ticks were unable to transmit the pathogen to na\uefve goats. Results of this study indicate that the Asian longhorned tick is not likely to play a significant role in the epidemiology of HGA in the United States.CC999999/ImCDC/Intramural CDC HHSUnited States/2021-01-24T00:00:00Z33590859PMC83832861021

Ticks Tick Borne Dis

The invasive, human-biting Asian longhorned tick, Haemaphysalis longicornis, was detected in New Jersey in the eastern United States in August of 2017 and by November of 2018 this tick had been recorded from 45 counties across 9 states, primarily along the Eastern Seaboard. The establishment of H. longicornis in the United States has raised the questions of how commonly it will bite humans and which native pathogens may naturally infect this tick. There also is a need for experimental vector competence studies with native pathogens to determine if H. longicornis can acquire a given pathogen while feeding, pass it transstadially, and then transmit the pathogen in the next life stage. In this experimental study, we evaluated the vector competence of a population of H. longicornis originating from the United States (New York) for a native isolate (B31) of the Lyme disease spirochete, Borrelia burgdorferi sensu stricto (s.s.). In agreement with a previous experimental study on the vector competence of H. longicornis for Borrelia garinii, we found that uninfected H. longicornis larvae could acquire B. burgdorferi s.s. while feeding on infected Mus musculus mice (infection prevalence >50% in freshly fed larvae) but that the infection was lost during the molt to the nymphal stage. None of 520 tested molted nymphs were found to be infected, indicating that transstadial passage of B. burgdorferi s.s. is absent or rare in H. longicornis; and based on the potential error associated with the number of nymphs testing negative in this study, we estimate that the upper 95% limit for infection prevalence was 0.73%. An Ixodes scapularis process control showed both effective acquisition of B. burgdorferi s.s. from infected mice by uninfected larvae and transstadial passage to the nymphal stage (infection prevalence of 80-82% for both freshly fed larvae and molted nymphs). We also observed that although H. longicornis larvae could be compelled to feed on mice by placing the ticks within feeding capsules, attachment and feeding success was minimal (<0.5%) when larvae were placed freely on the fur of the mice. We conclude that H. longicornis is unlikely to contribute more than minimally, if at all, to transmission of Lyme disease spirochetes in the United States.CC999999/ImCDC/Intramural CDC HHS/United States2021-01-01T00:00:00Z31640938PMC70549388874vault:3488

Morphological identification of ticks and molecular detection of tick-borne pathogens from bare-nosed wombats (Vombatus ursinus)

Background: Ticks are obligate haematophagous ectoparasites of vertebrate hosts and transmit the widest range of pathogenic organisms of any arthropod vector. Seven tick species are known to feed on bare-nosed wombats (Vombatus ursinus), in addition to the highly prevalent Sarcoptes scabiei mite which causes fatal sarcoptic mange in most bare-nosed wombat populations. Little is known about the pathogens carried by most wombat ticks or how they may impact wombats and wombat handlers. Methods: Wombat ticks were sourced from wildlife hospitals and sanctuaries across Australia and identifed to species level using taxonomic keys. Genomic DNA was extracted from a subsample, and following the amplifcation of the bacterial 16S rRNA gene V3–V4 hypervariable region, next-generation sequencing (NGS) on the Illumina MiSeq platform was used to assess the microbial composition. Results: A total of 447 tick specimens were collected from 47 bare-nosed wombats between January 2019 and January 2020. Five species of ticks were identifed comprising wombat tick Bothriocroton auruginans (n = 420), wallaby tick Haemaphysalis bancrofti (n = 8), bush tick Haemaphysalis longicornis (n = 3), common marsupial tick Ixodes tasmani (n = 12), and Australian paralysis tick Ixodes holocyclus (n = 4). Tick infestations ranged from one to 73 ticks per wombat. The wombat tick was the most prevalent tick species comprising 94% of the total number of samples and was present on 97.9% (46/47) of wombat hosts. NGS results revealed the 16S rRNA gene diversity profle was predominantly Proteobacteria (55.1%) followed by Firmicutes (21.9%) and Actinobacteria (18.4%). A species of Coxiella sharing closest sequence identity to Coxiella burnetii (99.07%), was detected in 72% of B. auruginans and a Rickettsiella endosymbiont dominated the bacterial profle for I. tasmani. Conclusions: A new host record for H. longicornis is the bare-nosed wombat. One adult male and two engorged adult female specimens were found on an adult male wombat from Coolagolite in New South Wales, and more specimens should be collected to confrm this host record. The most prevalent tick found on bare-nosed wombats was B. auruginans, confrming previous records. Analysis of alpha-diversity showed high variability across both sample locations and instars, similar to previous studies. The detection of various Proteobacteria in this study highlights the high bacterial diversity in native Australian ticks

Resistencia a los antihelmínticos en bovinos del nordeste de Corrientes (Argentina)

El objetivo del trabajo fue determinar la prevalencia de la resistencia a los antiparasitarios contra los nematodes gastrointestinales de bovinos en el nordeste de Corrientes. El área de estudio comprendió 4 establecimientos ganaderos de los departamentos Ituzaingó y Santo Tomé. El periodo de estudio abarcó de marzo de 2014 a agosto de 2016. La unidad de análisis fue el ternero destete. El método utilizado fue el test de reducción del conteo de huevos. La prevalencia de la resistencia antihelmíntica a la ivermectina en los 4 establecimientos ganaderos muestreados en este estudio fue del 100% y para el benzimidazol fue del 25%. Los géneros parasitarios resistentes a la ivermectina fueron Haemonchus y Cooperia. Estos resultados demuestran un aumento de la resistencia antihelmíntica si se comparan con estudios previos realizados en otros lugares del país