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Objectives Australian guidelines recommend people aged 50 to 70-years-old, consider taking low-dose aspirin to reduce their risk of colorectal cancer. The aim was to design sex-specific decision aids (DAs) with clinician and consumer input including expected frequency trees (EFTs) to communicate risks and benefits of taking aspirin. Methods Semi-structured interviews were conducted with clinicians. Focus groups were conducted with consumers. The interview schedules covered ease of comprehension, design, potential effects on decision making, and approaches to implementation of the DAs. Thematic analysis was employed; independent coding by two researchers was inductive. Themes were developed through consensus between authors. Results Sixty-four clinician were interviewed over six-months in 2019. Twelve consumers, aged 50 to 70 years, participated in two focus groups in February and March 2020.

BackgroundAmong protozoan parasites in the genus Babesia, Babesia bigemina is endemic and widespread in the East African region while the status of the more pathogenic Babesia bovis remains unclear despite the presence of the tick vector, Rhipicephalus microplus which transmits both species. Recent studies have confirmed the occurrence of R. microplus in coastal Kenya and although B. bovis DNA has previously been detected in cattle blood in Kenya, no surveillance has been done to establish its prevalence. This study therefore investigated the occurrence of B. bovis in cattle in Kwale County, Kenya, where R. microplus is present in large numbers. MethodA quantitative species-specific multiplex Taqman PCR assay targeting two Babesia bovis genes, 18S ribosomal RNA and mitochondrially-encoded cytochrome b and Babesia bigemina cytochrome b gene was used to screen 506 cattle blood DNA samples collected from Kwale County for presence of Babesia parasite DNA. ResultsA total of 131 animals (25.8%) were found to have bovine babesiosis. Of these, 87 (17.2%) were positive for B. bovis while 70 (13.8%) had B. bigemina while 26 (5.1%) were observed to be co-infected with both Babesia species. A total of 61 animals (12.1%) were found to be infected with B. bovis parasites only, while 44 animals (8.7%) had B. bigemina only. B. bovis infections were detected in 11 sites while B. bigemina was detected in 9 out of the 12 sites sampled in three Kwale sub-Counties.ConclusionThese findings reveal high prevalence of pathogenic B. bovis in a Kenyan area cutting across a busy transboundary livestock trade route with neighboring Tanzania. The Babesia multiplex assay used in this study is specific and can detect and differentiate the two Babesia species and should be used for routine B. bovis surveillance to monitor the spread and establishment of the pathogen in other African countries where B. bigemina is endemic. Moreover, these findings reveal a potential threat of fatal babesiosis in the absence of endemic stability in the local cattle populations.

Background: In regions with endemic Theileria orientalis, recovered cattle are carriers, leaving newborn calves and introduced stock as the most susceptible groups to develop clinical disease after tick infestation. Methods: To gain information on the kinetics of infestation and development and effects of parasitosis by virulent Theilerial genotypes ikeda and chitose and the “benign” genotype, buffeli, this study sampled at total of 150 calves from 3 farms in Dorrigo, Australia, a region with multiple genotypes of the parasite. In addition, 30 introduced beef weaners were bled and weighed for 6 months after arrival. Results: In both cohorts, parasitosis with the T.orientalis ikeda and chitose (genotypes 1 & 2) occurred within 3-4 weeks in >95% of the groups, with maximal gene copies generated around 5-7 weeks after birth or introduction, before declining. In contrast, parasitosis with T.orientalis buffeli (genotype 3), increased slowly, with around 80% of the population testing positive by PCR after 4 months. The parasitosis with the buffeli genotype did not exceed 40000 gene copies /ul and was similar to those exhibited by ikeda and chitose genotypes following the “first wave of parasitaemia” as cattle entered the carrier state. In the 30 introduced weaners, the early parasitosis with T.orientalis ikeda and chitose also caused significant reductions in haematocrit and incurred around 20Kg loss in weight gain; the latter had not been recovered by 6 months after introduction. Conclusions: The results support previous findings in other endemic regions of Theileriosis, but imply that amelioration of the early high levels of parasitosis by the virulent genotypes could reduce the initial impact of Theileriosis on production, which appears much less affected once animals enter the carrier state.

Background: An investigation aimed to confirm whether immunisation with the “benign” buffeli genotype of Theileria orientalis could reduce the parasitosis of the virulent ikeda genotype. Methods: Calves were inoculated intravenously or subcutaneously with bovine blood containing merozoites of T.orientalis buffeli. When recipients became positive, they and control animals were challenged with unfed nymphs of Haemaphysalis longicornis ticks infested as larvae with T.orientalis ikeda. Results: All calves became positive for the challenge within 12 days after tick application. In the immunised calves, the first wave of parasitosis with T.orientalis ikeda from 4-6 weeks was reduced significantly by >80% before the infestation declined into the carrier state by 9 weeks. Conclusions: The results confirm the field experience with theileriosis in endemic zones where the carrier state appears to prevent clinical disease despite repeated, seasonal tick infestations with virulent genotypes of the parasite. This method offers a means to reduce the severity of the first wave of theilerial parasitosis after tick challenge and recover associated production losses.

Background The tick vector Rhipicephalus (Boophilus) microplus which transmits Babesia and rickettsial pathogens has not been reported in Kenya since 1998. More recently, the pathogenic Babesia bovis has been detected in cattle blood DNA. The status of R. microplus in Kenya remains unknown. This study employed morphological and molecular tools to characterize R. microplus originating from Kenya and assess the genetic relationships between Kenyan and other African R. microplus genotypes. Methods Morphological identification and differentiation of 35 Kenyan and 11 reference tick specimens was implemented by following standard tick reference keys and identification guides. Genetic and phylogenetic relationships between the Kenyan and other annotated R. microplus reference sequences was investigated by analysis of the cytochrome c oxidase subunit I (COI) gene. The complete mitochondrial (mt) genome of four tick specimens which included two R. microplus was assembled from whole genome data to further characterize the Kenyan ticks. A B. bovis specific Taqman probe qPCR assay was used to detect B. bovis in gDNA from R. microplus ticks. Results Of the 35 Kwale tick specimens analysed, 23 were confirmed to be R. microplus by both morphology and molecular characterizations. The Kenyan R. microplus COI sequences showed very high pairwise identities (>99%) and clustered very closely with reference African sequences. We also found a low differentiation and lack of geographical sub-structuring among the African COI sequences. The mitochondrial genome sequences of the two Kenyan R. microplus ticks also clustered closely with reference genome sequences from Brazil, USA, Cambodia and India. No B. bovis was detected in the Kwale R. microplus DNA. Conclusions These findings confirm the presence of R. microplus in Kenya and suggest that a common undifferentiated genotype is prevalent in cattle in Africa. These and other recent findings of widespread occurrence of R. microplus in Africa provide a strong justification for urgent surveillance to determine and monitor the spread of R. microplus and vector competence of Rhipicephalid ticks for B. bovis in Africa, with the ultimate goal of strategic control.