Incidental finding of a human-like tusavirus in a lamb with lip lesions and fatal pneumonia.

Tusaviruses in the genus Protoparvovirus of family Parvoviridae were first identified in a diarrhoeic Tunisian child in 2014. Thereafter, high prevalence of a genetically similar virus was demonstrated in faeces from caprine and ovine species in Hungary. Here, we describe an investigation into the cause of scabby lip lesions in a 6 month-old lamb, submitted from a farm experiencing weight loss and scouring in lambs in England. Transmission electron microscopy visualised small circular particles of 18 and 22 nm in diameter in lip lesions identified as tusavirus and flumine parvovirus by Next Generation Sequencing. Liver, kidney, lung, small intestine content and faeces were also strongly positive for the tusavirus DNA as well as 10 % of faecal samples of the flock collected 2 months after the initial lip sampling. NS1 and VP1 amino acid sequences of this tusavirus displayed 99.5 and 92.89 % identity to those of a human tusavirus, respectively. These amino acid identities were at 95.5 and 89.68 % when compared to those of a goat tusavirus. Phylogenetic analysis of the NS1 and VP1 also grouped the virus in the genus Protoparvovirus and close to tusaviruses detected in human, ovine and caprine species. Wider surveillance of the virus indicated a broader geographical distribution for the virus in England. Histology of the lip tissue revealed localised areas of epidermal hyperplasia and hyperkeratosis affecting haired skin, with mild leucocyte infiltration of the subjacent dermis, but no changes to implicate virus involvement. Flumine parvovirus was concluded to be an environment contaminant. Broader studies in prevalence of these virus in UK sheep flocks and human population, animal models and experimental infections could provide insights into the pathogenesis of these novel viruses and their zoonotic potential.

Anaplasma phagocytophilum Ecotype Analysis in Cattle from Great Britain.

Anaplasma phagocytophilum (A. phagocytophilum) is the aetiological agent of tick-borne fever in cattle and sheep, and granulocytic anaplasmosis in human and dogs. Livestock, companion animal and human infections with A. phagocytophilum have been reported globally. Across England and Wales, two isolates (called ecotypes) have been reported in ticks. This study examined A. phagocytophilum isolates present in livestock and wildlife in Great Britain (GB), with a particular focus on cattle. Clinical submissions (EDTA blood) from cattle (n = 21) and sheep (n = 3) were received by APHA for tick-borne disease testing and the animals were confirmed to be infected with A. phagocytophilum using a PCR targeting the Msp2 gene. Further submissions from roe deer (n = 2), red deer (n = 2) and Ixodes ricinus ticks (n = 22) were also shown to be infected with A. phagocytophilum. Subsequent analysis using a nested PCR targeting the groEL gene and sequencing confirmed the presence of ecotype I in cattle, sheep, red deer and Ixodes ricinus, and ecotype II in roe deer and I. ricinus removed from deer carcasses. Despite the presence of two ecotypes, widely distributed in ticks from England and Wales, only ecotype I was detected in cattle in this study.

Surveillance and Risk Analysis for Bovine Babesiosis in England and Wales to Inform Disease Distribution.

Babesia divergens is a zoonotic piroplasm that infects both cattle and humans in Europe. Disease transmission occurs through Ixodes ricinus tick bites, a species that is increasing in abundance and distribution across Europe in response to climate and land-use changes. Developments in agri-environment policy and changing consumer demands may also have unintended consequences on tick-borne disease rates. Currently, B. divergens surveillance in British cattle is limited, rendering temporal trend analysis and the detection of potential zoonotic hotspots impossible. The objective of this study was to assess syndromic surveillance as a means of determining babesiosis distribution in British cattle, and to evaluate the intrinsic disease risk factors in order to respond to disease threats posed by changing environments. Samples from 95 clinically affected cattle on 70 unique holdings were screened for Babesia spp., using established blood smear examination techniques and a B. divergens-specific PCR method, between April and December 2021. B. divergens was detected in 45/95 animals (47.4%), with PCR offering the advantage of identification at species level. Infection with Anaplasma phagocytophilum was detected in 19/95 animals (20%). Co-infection was detected in five animals. The cases were recorded across multiple geographic regions and throughout the sampling period. Univariate logistic regression analysis failed to identify any statistically significant risk factors for B. divergens presence. This study demonstrates that bovine babesiosis is geographically widespread throughout England and Wales, placing a large proportion of the cattle population at risk of infection, with the potential for zoonotic transmission to humans.

Retrospective analysis of necrotizing typhlitis cases associated with Brachyspira spp. in British rheas.

This paper describes a retrospective analysis of necrotizing typhlitis in common rheas (Rhea americana) diagnosed in the United Kingdom by the Animal & Plant Health Agency (APHA). From January 2008 to January 2020, seven cases of spirochaetal typhlitis associated with Brachyspira spp. were identified using the Veterinary Investigation Diagnosis Analysis database. Gross examination was combined with selective anaerobic culture, polymerase chain reaction, and histopathology to diagnose typhlitis associated with spirochaetal infection. Whole-genome sequencing was subsequently utilized on archived isolates from six of the seven submissions, overcoming issues with traditional testing methods and yielded gains in the identification of Brachyspira to species level. Brachyspira hyodysenteriae, an organism traditionally associated with typhlitis in rheas, was isolated in three sequenced submissions. One of these also demonstrated co-infection with Brachyspira intermedia. Brachyspira suanatina, Brachyspira hampsonii, and Brachyspira alvinipulli were identified by sequencing as single infections in the remaining three animals. This report demonstrates the ability of Brachyspira species other than B. hyodysenteriae to colonize the caeca of rheas presenting with typhlitis. Additionally, the B. alvinipulli isolate harboured a tva(A) gene, indicating higher potential pleuromutilin resistance, which has not previously been described in this Brachyspira species. This study discusses the epidemiology of examined cases and examines the potential role other species may play in these outbreaks.

An outbreak of bovine babesiosis in February, 2019, triggered by above average winter temperatures in southern England and co-infection with Babesia divergens and Anaplasma phagocytophilum.

BACKGROUND: Bovine babesiosis, commonly known as redwater fever, is a sporadic tick-borne disease in the United Kingdom. Outbreaks occur during the spring, summer and autumn months when ticks are active. This study reports the findings of an investigation of an outbreak of bovine babesiosis during the winter month of February, 2019. METHODS: DNA from blood, organ and tick samples taken from affected cattle were tested for the presence of piroplasm and Anaplasma phagocytophilum DNA using PCRs directed to the 18S rRNA gene and msp2 gene respectively. The species of piroplasm was confirmed by sequencing. RESULTS: Babesia divergens DNA was detected in the blood of five cattle displaying clinical signs of babesiosis within a herd of twenty. This parasite was also detected in three of ten ticks removed from one of the affected cattle. In addition, A. phagocytophilum was detected in three cattle tested and two of ten of the ticks. CONCLUSIONS: An outbreak of bovine babesiosis during February is unusual as the tick vector, Ixodes ricinus, does not generally become active until temperatures rise later in the year. February of 2019 was unusual as average temperatures during the first week of the month reached over 10 °C, well above historical averages that are typically below 5 °C, and a temperature at which ticks can become active. This unusual weather event is likely to have triggered tick questing, that combined with a co-infection with two tick-borne pathogens caused the severe outbreak of disease.