March 2025: A collection of publication highlights from Edinburgh Infectious Diseases over the past month. The diagnosis and vector potential of Ornithonyssus bacoti tropical rat mites in northern Europe The tropical rat mite, Ornithonyssus bacoti, is an important cause of disease in small rodents, and of gamasoidosis (zoonotic dermatitis) in humans when they come into contact with infestations. Most reports of O. bacoti infestations are from warmer parts of the Americas, southern Europe and Asia, but in 2021 and 2024 two separate cases of gamasoidosis were identified in student flats in the city of Edinburgh. Researchers from the Royal (Dick) School of Veterinary Studies explored the bacterial microbiome associated with the mites. The results show the presence of potentially pathogenic bacteria and indicate the potential for O. bacoti mites as vectors of bacterial infections. Citation: Sargison ND, Chaudhry U, Costa-Junior L, Kutcher JR, Li K, Sargison FA, Zahid O. Vet Parasitol Reg Stud Reports. 2025 Feb;58:101204. doi: 10.1016/j.vprsr.2025.101204. Epub 2025 Jan 20. PMID: 40049993. Read the full article here Acute LPS exposure enhances susceptibility to peripheral prion infection In this study, from the PhD thesis of Reiss Pal (The Roslin Institute & R(D)SVS) we showed intraperitoneal LPS injection significantly enhanced prion disease susceptibility approximately 100X when given 24–3 h before infection. The effects on disease susceptibility coincided with the reduced abundance of macrophages within the peritoneal cavity at the time of infection and the enhanced early accumulation of prions in the spleen. These data suggest that the reduced recoverable abundance of macrophages in the peritoneal cavity following acute LPS-treatment, increased disease susceptibility by enhancing the initial propagation of the prions from site of exposure (peritoneal cavity) to the spleen from where they subsequently spread to the brain. Citation: Pal, R., Thomas, C.M., Salamat, K. et al. Sci Rep 15, 9754 (2025). https://doi.org/10.1038/s41598-025-94003-3 Read the full article here Cas10 based 7SL-sRNA diagnostic for the detection of active trypanosomosis Animal Trypanosomosis (AT) is a parasitic disease that affects livestock, causing major economic losses and harm to animal health. Cheap effective diagnostics that can be easily used in the field would have a major impact on the disease burden by enabling better treatment practices. Here, researchers from the Roslin Institute and the Institue of Immunology and Infection Research develop a field applicable Cas10 based lateral flow diagnostic test that targets a small RNA expressed by Trypanosomes. This is the first time Cas10 technology has been used to detect small RNAs using a lateral flow assay, offering a promising, cost-effective tool for diagnosing AT and potentially other neglected parasitic diseases. Citation: Grüschow S, Steketee PC, Paxton E, Matthews KR, Morrison LJ, White MF, Grey F. PLoS Negl Trop Dis. 2025 Mar 17;19(3):e0012937. doi: 10.1371/journal.pntd.0012937. Epub ahead of print. PMID: 40096045. Read the full article here Understanding the Potential of a Short-Term Participatory Video Project for Long-Term Change Chancellor's Fellow Jess Mitchell and colleagues at the University of Leeds (UK) and HERD International (Nepal) have recently published on the ability of community engagement methods to create long-term behavioural change on drivers of antimicrobial resistance (AMR). Jess and colleagues returned to participants who had been engaged in a participatory video (PV) project over two years previous. They found that participants had retained knowledge of AMR drivers, held important AMR advocacy roles in their communities and self-reported notable changes in how they and their communities have increased antimicrobial stewardship; for example by seeking health and veterinary professional advice before using drugs, completing full drug courses and avoiding prophylactic use. Findings suggest investment in community engagement methods have tangible, long-term benefits in terms of behaviour change. This is particularly important in the context of antimicrobial resistance as although behaviour drivers of AMR are commonly recognised, sustainable interventions are often difficult to evidence. Findings of this paper have been shared with policy makers in Nepal with the aim of increasing investment in community engagement activities to address AMR. Citation: Mitchell, J., Jones, N., A., Arjyal, A., Baral, S., King, R., Manadhar, S., & Cooke, P. (2025). Journal of Participatory Research Methods, 6(1), 94–114. https://doi.org/10.35844/001c.128256 Read the full article here Demography of owned dogs across an East African continuum of high-low human density Accurate data on dog populations is critical for planning disease control measures such as rabies vaccination. This study surveyed households across urban and rural areas of Machakos County, Kenya, to estimate the number of owned dogs and factors influencing ownership. The results revealed a higher-than-expected dog population, with ownership patterns influenced by household size, wealth, and livestock keeping. These insights can help inform more efficient and targeted approaches to disease control, especially in transitioning rural-urban environments. Citation: Maurice K. Murungi, Lian F. Thomas, Nicholas Bor, Ian Masaku, Mercy Anyango, Peterkin N. Munywoki, Camille Glazer, Dishon M. Muloi, Eric M. Fèvre, Preventive Veterinary Medicine, 2025, 106518, ISSN 0167-5877, https://doi.org/10.1016/j.prevetmed.2025.106518. Read the full article here Exploring the effects of dietary lysine and tryptophan on the social behavior of pigs Negative social behaviors in pigs can lead to stress and affect their well-being. Researchers from Scotland's Rural College and the Roslin Institute are interested in how diet might influence these behaviors and overall social interactions in pigs. This study looked at how two specific nutrients, Lysine (Lys) and Tryptophan (Trp), in pigs' diets might impact their social behavior. The study involved 2,293 pigs, with an average starting weight of 11.87 kg. The pigs were divided into different groups based on two factors: the amount of Lysine in their diet (100% of the recommended amount vs. 80% of the recommended amount) and the ratio of Tryptophan to Lysine (three different ratios). The researchers observed the pigs' behavior and recorded any injuries, such as ear-biting. They found that pigs on the lower Lysine diet (80%) were more likely to engage in ear-biting. Additionally, the study showed that both the amount of Lysine and the combination of Lysine and Tryptophan in their diets affected the likelihood of ear lesions (injuries) in the pens. In conclusion, the amount of Lysine in pigs' diets can influence their social behaviors, particularly ear-biting, in commercial farming environments. Citation: Hewett E, Zaragoza L, Lewis C, Houdijk J, Wilson A, Turner S. J Anim Sci. 2025 Jan 4;103:skaf030. doi: 10.1093/jas/skaf030. PMID: 39910971; PMCID: PMC11912881. Read the full article here Investigation of ceftriaxone-resistant Neisseria gonorrhoeae detected in Scotland, 2018–2024 Researchers from NHS Lothian have been looking into Neisseria gonorrhoeae which is a leading sexually transmitted pathogen and has developed antimicrobial resistance to all drug classes. Ceftriaxone is the mainstay for gonorrhoea treatment in the UK and resistance is uncommon. This work involved clinical, laboratory, and genomic analysis of the first five ceftriaxone-resistant N. gonorrhoeae identified in Scotland. All ceftriaxone-resistant cases in Scotland were due to acquisition in, or via travellers from, the Asia-Pacific where resistance is more common. However, two sexual contacts in Scotland could not be traced, raising the risk of circulation within the community. Genomic analysis confirmed links to international lineages, although two isolates were the first detections of ceftriaxone resistance in a previously sensitive lineage. This work highlights the ongoing need for robust surveillance to detect the spread and development of ceftriaxone resistance in N. gonorrhoeae Citation: McHugh MP, Aburajab K, Maxwell A, Anderson J, Cairns F, Cotton S, Gough A, Malloy B, Mathers K, Renwick L, Shepherd J, Templeton KE. Sex Transm Infect. 2025 Mar 6:sextrans-2024-056405. doi: 10.1136/sextrans-2024-056405. Epub ahead of print. PMID: 40050018. Read the full article here Publication date 25 Mar, 2025
