October 2024: A collection of publication highlights from Edinburgh Infectious Diseases over the past month. An older female macaque hangs out with a buddy on the island of Cayo Santiago Social ageing can protect against infectious disease in a group-living primate Maintaining social connections is important for health and wellness across many species, but humans and other animals often shrink their social networks as they age. Researchers from the Institute of Ecology and Evolution at the University of Edinburgh in collaboration with colleagues from the Centre for Research in Animal Behaviour at the University of Exeter have been exploring the interplay between this ‘social ageing’ and infectious disease. By simulating pathogen spread through a population of free-ranging Rhesus macaques they demonstrate a potentially important role for infectious disease, suggesting that reducing social networks later in life when immune systems are typically weakened might carry important health benefits. Citation: Siracusa Erin R., Pavez-Fox Melissa A., Negron-Del Valle Josué E., Phillips Daniel, Platt Michael L., Snyder-Mackler Noah, Higham James P., Brent Lauren J. N. and Silk Matthew J. 2024, Phil. Trans. R. Soc. B37920220462 Read the full article here Benchmarking sustainability performance in UK free-range laying hen flocks Considering the need to nourish a growing human population, whilst tackling multiple environmental and social challenges, there is a need to evaluate the relative performance farming systems based on an array of sustainability objectives. Researchers from the Global Academy of Agriculture and Food Systems benchmarked the sustainability performance of 80 UK free-range laying hen flocks. They used the linear programming technique 'Data Envelope Analysis' to assign multi-criteria scores to the flocks, based on environmental, animal welfare, antimicrobial use, and production metrics. Some flocks achieved superior performance across multiple sustainability objectives. Differences in scores amongst farms with similar production systems were likely due to laying hen breed and unmeasured human factors. The authors conclude that breeds with balanced genetic merit will play an important role in food systems seeking to mitigate externalities of production. In addition, they demonstrate use of this methodology in deriving balanced sustainability metrics for farming systems including the neglected measures of animal welfare and antimicrobial use. They propose that this method could be used to incentivise best practice within supply chains or government schemes. Citation: L.E. Higham, I. Handel, L. Boden, D. Moran, Agricultural Systems, Volume 221, 2024, 104103, ISSN 0308-521X Read the full article here Clinical sub-phenotypes of Staphylococcus aureus bacteraemia S. aureus bacteraemia (SAB) is a clinically heterogeneous disease, and the ability to identify sub-groups of patients with shared traits (sub-phenotypes) is an unmet need that could allow patient stratification for clinical management and research. Researchers from The Roslin Institute, Centre for Inflammation Resarch, Clinical Infection Research Group and Edinburgh Medical School studied three cohorts of patients (n=1430 in total) and were able to identify reproducible and clinically-relevant sub-phenotypes within SAB. We re-analysed results of a clinical trial using this approach, identifying differential treatment effects which were not observed in the original trial analysis. These sub-phenotypes could contribute to a personalised medicine approach to SAB. Citation: Swets MC, Bakk Z, Westgeest AC, Berry K, Cooper G, Sim W, Lee RS, Gan TY, Donlon W, Besu A, Heppenstall E, Tysall L, Dewar S, de Boer M, Fowler VG Jr, Dockrell DH, Thwaites GE, Pujol M, Pallarès N, Tebé C, Carratalà J, Szubert A, Groeneveld GH, Russell CD. Clin Infect Dis. 2024 Read the full article here Evaluation of the Protective Efficacy of Different Doses of a Chlamydia abortus Subcellular Vaccine in a Pregnant Sheep Challenge Model for Ovine Enzootic Abortion Researchers from the Moredun Research Institute have been looking into Chlamydia abortus that causes the disease ovine enzootic abortion - this is one of the most infectious causes of foetal death in small ruminants worldwide. Researchers have previously reported a new prototype vaccine based on a ddetetrgent-extracted membrane protein of Chlamydia abortus that was more effective and safer than the commercial vaccines when adminstered in a particular way. In this new study, researchers have developed the vaccine further andd found that the new formulations performed well in comparison to the unvaccined control group. Citation: Livingstone M, Aitchison K, Palarea-Albaladejo J, Chianini F, Rocchi MS, Caspe SG, Underwood C, Flockhart A, Wheelhouse N, Entrican G, Wattegedera SR, Longbottom D. Animals (Basel). 2024 Read the full article here Repositioning Brusatol as a Transmission Blocker of Malaria Parasites Researchers from the Institute of Immunology and Infection Research have been looking into the importance of discovering new agents to regulate malarial transmission. Currently there is only one malaria transmission-blocking drug recommended by the WHO. In this study, researchers demonstrate an approach to identify malaria transmission-blocking agents through a combination of in vitro screening and in vivo analyses. In particular, researchers have been looking into the effiacy of brusatol which is a plant-derived natural quassinoid that is increasingly studied for its anticancer activity. Using a panel of natural products, their approach identified potent transmission blockers, as illustrated by the discovery of the transmission-blocking efficacy of brusatol. Citation: Cox A, Krishnankutty N, Shave S, Howick VM, Auer M, La Clair JJ, Philip N. ACS Infect Dis. 2024 Read the full article here Early changes in the gut microbiome among HIV-infected Individuals in Uganda initiating daily TMP/SMX Researchers from the Roslin Institute have contributed to studying the early effects of daily cotrimoxazole (TMP/SXT) prophylaxis (a part of the HIV treatment passage) on the gut microbiome. To study the early effects, they analysed shotgun metagenome sequence data from stool samples of five newly HIV-infected individuals initiating HIV treatment and then using certain sequencing methods, researchers generated profiles for each patient and compared gut microbial changes. Researchers concluded that TMP/SXT daily prophylaxis in HIV-infected individuals is associated with dramatic changes in microbial composition and functional profiles; however, other factors such as Age, Gender, HIV clinical stage, and ART regiment are at play. Citation: Atugonza C, Muwonge A, Najjuka CF, Kateete DP, Katagirya E, Mwesigwa S, Asiimwe B. medRxiv [Preprint]. 2024 Read the full article here Why medical products must not be excluded from the Global Plastics Treaty Researchers from the School of Social and Political Science have been following discussions about health as part of negotiations for a Global Plastics Treaty to end pollution from plastics. Researchers are bringing together perspectives from social policy, anthropology and history, and working with the international NGO Health Care Without Harm to understand how health features in the negotiations, and what is at stake for different actors in the ways in which relationships between health and plastics are framed. This comment for the Lancet argues that current proposals for a blanket exemption for health and medical products from Treaty provisions presents a weak and inconsistent position on plastics and health, obscuring the risks that plastics pose to health and playing into the hand of vested commercial interests who push a ‘plastics save lives’ mantra. Citation: Street A, Stringer R, Mangesho P, Ralston R, Greene J. Why medical products must not be excluded from the Global Plastics Treaty. Lancet. 2024 Oct Read the full comment here Publication date 30 Oct, 2024
