Portrait photo of Sara Frosth

Sara Frosth

Associate Professor, Researcher, HBIO, Bacteriology, Virology, Food Safety and Veterinary Public Health
Phone
+4618672364
I am an Associate Professor in Biomedical Sciences with a focus on veterinary bacteriology. My research concerns bacterial infections in animals, with emphasis on diagnostics, preventive measures and vaccine development, using bacteriology, molecular biology and bioinformatics.

Presentation

I am an Associate Professor in Biomedical Science with a specialization in Veterinary Bacteriology and a background as a PhD in Biotechnology. I have an interdisciplinary profile with a particular interest in veterinary bacteriology, molecular biology, bioinformatics, protein technology, and vaccinology.

My research focuses on bacterial infections in animals, particularly in relation to pathogenesis, diagnostics, and preventive strategies. I earned my PhD in 2016 with a dissertation on Dichelobacter nodosus and footrot in sheep, in which I studied genetic diversity, virulence factors, and potential diagnostic targets. During my postdoctoral period (2017–2019), I conducted research on Campylobacter in broiler chickens, focusing on transmission routes and control measures.

I combine molecular biology and bioinformatics methods in my research and have a strong interest in translational research that can improve animal health and contribute to more sustainable food production.

Research

Vaccine against Streptococcus suis in pigs and Staphylococcus aureus in cattle.

Streptococcus equi and strangles in horses - Vaccine and diagnostics.

Development of a new diagnostic test to prevent claw diseases in sheep. Project leader (Petra Lundberg Foundation 2023-2025).

Development of an improved and objective diagnostic tool for digital dermatitis in cattle. Project participant (Seydlitz MP Companies Foundation 2023-2025; Project leader Anna Rosander).

Research projects

Teaching

Course module leader and lecturer in veterinary bacteriology on the course "Molecular cell biology and microbiology", BI1391 (15 credits), 2025.

Course leader and examiner for the course "Animal biology 2 - the cell", HV0133 (15 credits), 2018-2020.

Course module leader and lecturer in veterinary bacteriology on the course "Parasitology, mycology and veterinary infection biology", 3MK001 (15 credits), 2018.

Lecturer in bacteriology at the veterinary programme, 2017-2023.

Educational credentials

Main supervisor:

PhD, Development of diagnostic tests for claw diseases in ruminants, ongoing

MSc, Prevalence of footrot and contagious ovine digital dermatitis in Swedish sheep – a field study, https://stud.epsilon.slu.se/18618/, 2023

MSc, Prevalence of clinical footrot and Dichelobacter nodosus in Swedish
slaughter lambs, https://stud.epsilon.slu.se/16530/, 2021

Co-supervisor:

PhD, Foodborne bacteria in slaughterhouses: with focus on cleaning and disinfection, https://res.slu.se/id/publ/126461, 2023

PhD, Control strategies for LA-MRSA in Swedish pig production: A disease modelling approach, https://res.slu.se/id/publ/121644, 2023           

Academic activities/assignments

Editorial board member for BMC Microbiology since 2023.

External examiner of PhD-thesis (University of Nottingham, UK) and Habilitation-thesis (University of Bern, Switzerland).

Reviewer for scientific journals such as: Animal Microbiome (Springer Nature), Animals (MDPI), Applied Sciences (MDPI), Biologicals (Elsevier), Environmental Microbiology and Environ. Microbiol. Reports (Wiley), Frontiers in Veterinary Science (Frontiers), Journal of Clinical Microbiology (ASM), Journal of Equine Veterinary Science (Elsevier), Molecular & Cellular Probes (Elsevier), Swiss Archive for Veterinary Science (Swiss Veterinary Society (GST|SVS)), Scientific Reports (Springer Nature), Vaccine (Elsevier), and Veterinary Microbiology (Elsevier).

Publications

Thesis:

Frosth S. (2016). Dichelobacter nodosus and footrot in Swedish sheep. Increased knowledge and improved laboratory diagnostics. http://pub.epsilon.slu.se/13845/

International:

McGlennon, A.A., Verheyen, K.L., Newton, R., van Tonder, A., Wilson, H., Parkhill, J., de Brauwere, N., Frosth, S., and Waller, A.S. (2025), Unwelcome neigh-bours: tracking the transmission of Streptococcus equi in the United Kingdom horse population. Equine Veterinary Journal. https://doi.org/10.1111/evj.14558

Sütterlin, S., Lindblad, M., Tano, E., Frosth, S., Farnebo, F., Schennings, T., Flock, J-I., and Huss, F. (2025), Role of Staphylococcus aureus colonization in burn patients. Journal of Infection, volume 91, issue 1. https://doi.org/10.1016/j.jinf.2025.106516

Frosth, S., Reddick, D., Righetti, F., Bjerketorp, J., Jacobsson, K., Henriques-Normark, B., Jacobson, M., Guss, B., Wood, T., Frykberg, L., Flock, J-I., and Waller, A.S. Sow vaccination with a novel recombinant protein vaccine protects piglets against Streptococcus suis infection. Vaccine, volume 53. https://doi.org/10.1016/j.vaccine.2025.127077

Wilson, H., Dong, J., van Tonder, A.J., Ruis, C., Lefrancq, N., McGlennon, A., Bustos, C.P., Frosth, S., Léon, A., Blanchard, A.M., Holden, M., Waller, A.S., and Parkhill, J. (2025), Progressive evolution of Streptococcus equi from Streptococcus equi subsp. zooepidemicus and adaption to equine hosts. Microbial Genomics, volume 11, issue 3. https://doi.org/10.1099/mgen.0.001366

Moazzami, M., Bergenkvist, E., Boqvist, S., Frosth, S., Langsrud, S., Møretrø, T., Vågsholm, I., and Hansson, I. (2024), Occurrence of Campylobacter, Listeria monocytogenes, and extended-spectrum beta-lactamase Escherichia coli (E. coli) in slaughterhouses before and after cleaning and disinfection. Food Microbiology, volume 125. https://doi.org/10.1016/j.fm.2024.104639

Ahlén, L., Holmøy, I. H., Sogstad, Å. M., Jensen, T. K., Frosth, S., Rosander, A., and Fjeldaas, T. (2024), Bovine Digital Dermatitis: Treponema spp. on trimming equipment and chutes – effect of washing and disinfection. BMC Veterinary Research, 20:261. https://doi.org/10.1186/s12917-024-03941-z

Roelofs, L., Frössling, J., Rosander, A, Bjerketorp, J., Belaghi, R. A., Hansson, I., and Frosth, S. (2024), Digital dermatitis in Swedish dairy herds assessed by ELISA targeting Treponema phagedenis in bulk tank milk. BMC Veterinary Research. https://doi.org/10.1186/s12917-024-04021-y

Rosander, A., Mourath, S., König, U., Nyman, A., and Frosth, S. (2023), Field study on the prevalence of ovine footrot, contagious ovine digital dermatitis, and their associated bacterial species in Swedish sheep flocks. Pathogens, 12, 1224. https://doi.org/10.3390/pathogens12101224

Bustos, C.P., Retamar, G., Leiva, R., Frosth, S., Ivanissevich, A., Demarchis, M.E., Walsh, S., Frykberg, L., Guss, B., Mesplet, M., and Waller, A. (2023), Novel genotype of Streptococcus dysgalactiae subsp. equisimilis associated with mastitis in an Arabian filly: genomic approaches and phenotypic properties. Journal of Equine Veterinary Science. https://doi.org/10.1016/j.jevs.2023.104913

Moazzami, M., Bergenkvist, E., Boqvist, S., Frosth, S., Langsrud, S., Møretrø, T., Vågsholm, I., and Hansson, I. (2023), Assessment of ATP-bioluminescence and dipslide sampling to determine the efficacy of slaughterhouse cleaning and disinfection compared with total aerobic and Enterobacterales counts. Journal of food protection. https://doi.org/10.1016/j.jfp.2023.100155

Frosth, S., Eriksson, H.K., and Rosander A. (2023), Development of a multiplex quantitative PCR assay for simultaneous detection of Treponema phagedenis, Treponema pedis, Treponema medium, and ‘Treponema vincentii’ and evaluation on bovine digital dermatitis biopsies. Veterinary Research Communications. https://doi.org/10.1007/s11259-023-10147-5

Tuominen, K., Frosth, S., Pedersen, K., Rosendal, T., and Sternberg-Lewerin, S. (2023), Survival of livestock-associated methicillin-resistant Staphylococcus aureus CC398 on different surface materials. Acta Veterinaria Scandinavica, 65:13. https://doi.org/10.1186/s13028-023-00676-z

Malaluang, P., Wilén, E., Frosth, S., Lindahl, J. F, Hansson, I., and Morrell, J. M. (2023), Antimicrobial resistance in vaginal bacteria in inseminated mares. Pathogens 12(3), 375. https://doi.org/10.3390/pathogens12030375

Malaluang, P., Wilén, E., Frosth, S., Lindahl, J. F, Hansson, I., and Morrell, J. M. (2022), Vaginal bacteria in mares and the occurrence of antimicrobial resistance. Microorganisms, 10 2204. https://doi.org/10.3390/microorganisms10112204

Rosander, A., Albinsson, R., König, U., Nyman, A., and Frosth, S. (2022), Prevalence of bacterial species associated with ovine footrot and contagious ovine digital dermatitis in Swedish slaughter lambs. Acta Veterinaria Scandinavica, 64, 6. https://doi.org/10.1186/s13028-022-00625-2

Frosth, S., Morris, E.R.A., Wilson, H., Frykberg, L., Jacobsson, K., Parkhill, J., Flock, J-I., Wood, T., Guss, B., Aanensen, D.M., Boyle, A.G., Riihimäki, M., Cohen, N.D., and Waller, A.S. (2022), Conservation of vaccine antigen sequences encoded by sequenced strains of Streptococcus equi subsp. equi. Equine Veterinary Journal. https://doi.org/10.1111/evj.13552

Hansson, I., Ellström, P., Nilsson, O., Chaba, M., Skarin, M., Fernström, L.-L., and Frosth, S. (2021). Differences in genotype and antimicrobial resistance between Campylobacter spp. isolated from organic and conventionally produced chickens in Sweden. Pathogens 10(12), 1630. https://doi.org/10.3390/pathogens10121630

Bernhard, M., Frosth, S., and König, U. (2021). First report on outbreaks of contagious ovine digital dermatitis in Sweden. Acta Veterinaria Scandinavica 63, 29. https://doi.org/10.1186/s13028-021-00595-x

Hansson, I., Tamminen., L-M., Frosth, S., Fernström, L-L., Emanuelson, U., and Boqvist, S. (2020). Occurrence of Campylobacter spp. in Swedish calves, common sequence types, and antibiotic resistance patterns. Journal of Applied Microbiology. https://doi.org/10.1111/jam.14914

Frosth, S., Lindsjö, OK., Niazi, A., Fernström, LL., and Hansson, I. (2020). Identification of transmission routes of Campylobacter and on-farm measures to reduce Campylobacter in chicken. Pathogens, 9(5), 363. https://doi.org/10.3390/pathogens9050363

Frosth, S., and Lewerin, S.S. (2019). Survival of Streptococcus equi subsp. equi in normal saline versus phosphate-buffered saline and at two different temperatures. Journal of Equine Veterinary Science, 83. https://doi.org/10.1016/j.jevs.2019.102814

Ferrari, S., Frosth, S., Svensson, L., Fernström, LL,. Skarin, H., and Hansson, I. (2019). Detection of Campylobacter spp. in water by dead-end ultrafiltration and application at farm level. Journal of Applied Microbiology. https://doi.org/10.1111/jam.14379

Frosth, S., Pringle, J., and Lewerin, S.S. (2018). Potential transmission of bacteria, including Streptococcus equi spp., between stables via visitors’ clothes. Journal of Equine Veterinary Science, 71: 71-74. https://doi.org/10.1016/j.jevs.2018.10.002

Locher, I., Giger, L., Frosth, S., Kuhnert, P., and Steiner, A. (2018). Potential transmission routes of Dichelobacter nodosus. Veterinary Microbiology, 218: 20-24. https://doi.org/10.1016/j.vetmic.2018.03.024

Frosth, S., König, U., Nyman, A.K., and Aspán, A. (2017). Sample pooling for real-time PCR detection and virulence determination of the footrot pathogen Dichelobacter nodosus. Veterinary Research Communications, 41(3), 189-193. http://dx.doi.org/10.1007/s11259-017-9686-9

Maboni, G., Blanchard, A., Frosth, S., Stewart, C., Emes, R., and Tötemeyer, S. (2017). A distinct bacterial dysbiosis associated skin inflammation in ovine footrot. Scientific Reports 7, 45220. http://dx.doi.org/10.1038/srep45220

Maboni G., Frosth S., Aspán A., and Tötemeyer, S. (2016). Ovine footrot: new insights into bacterial colonization. Veterinary Record, (179). http://dx.doi.org/10.1136/vr.103610

Frosth, S., König, U., Nyman, A-K., Pringle, M., and Aspán, A. (2015). Characterisation of Dichelobacter nodosus and detection of Fusobacterium necrophorum and Treponema spp. in sheep with different clinical manifestations of footrot. Veterinary Microbiology, 179 (1-2):82-90. http://dx.doi.org/10.1016/j.vetmic.2015.02.034

Kennan RM., Gilhuus M., Frosth S., Seemann T., Dhungyel O., Whittington R., Boyce JD., Aspán A., Jørgensen HJ., Bulach DM., and Rood, JI. (2014). Genomic evidence for a globally distributed, bimodal population in the ovine footrot pathogen Dichelobacter nodosus. mBio 5(5):e01821-14. http://dx.doi.org/10.1128/mBio.01821-14

Frosth S., Slettemeås JS., Jørgensen HJ., Angen Ø., and Aspan A. (2012). Development and comparison of a real-time PCR assay for detection of Dichelobacter nodosus with culturing and conventional PCR: harmonisation between three laboratories. Acta Veterinaria Scandinavica, 31;54(1). http://dx.doi.org/10.1186/1751-0147-54-6

Lindahl S., Söderlund R., Frosth S., Pringle J., Båverud V., and Aspán, A. (2011). Tracing outbreaks of Streptococcus equi infection (strangles) in horses using sequence variation in the seM gene and pulsed-field gel electrophoresis. Veterinary Microbiology, 153 (1-2):144-9. http://dx.doi.org/10.1016/j.vetmic.2011.03.027

Båverud V., Johansson SK., and Aspán, A. (2007). Real-time PCR for detection and differentiation of Streptococcus equi subsp. equi and Streptococcus equi subsp. zooepidemicus. Veterinary Microbiology, 124 (3-4):219-29. http://dx.doi.org/10.1016/j.vetmic.2007.04.020

Johansson S., Feinstein RE., Johansson KE., and Lindberg, A. (2006). Occurrence of Helicobacter species other than H. hepaticus in laboratory mice and rats in Sweden. Comparative Medicine, 56(2): 110-13.

Salomonsson AC., Aspán A., Johansson S., Heino A., and Häggblom, P. (2005). Salmonella detection by polymerase chain reaction after pre-enrichment of feed samples. Journal of Rapid Methods and Automation in Microbiology, 13 (2): 96-110. http://dx.doi.org/10.1111/j.1745-4581.2005.00012.x

National:

Albinsson, R., Rosander, A., König, U., Nyman, A., Aspán, A., Averpil, H-B., and Frosth, S. (2021). Förekomst av Dichelobacter nodosus och fotröta hos svenska slaktlamm. Svensk Veterinärtidning nr 9, sidor 38-41.

Bernhard, M., Frosth, S., Lindqvist-Frisk, K., and König, U. (2019). Ny smittsam klövsjukdom i svensk fårbesättning. Svensk Veterinärtidning, nr 11 sidor 32-36.

Angen Ø., Akkad NB., Worm R., Nymand A., Frosth S., Aspán A., Slettemeås JS., Jørgensen H., and Klaas, I.C. (2011). Detektion af Dichelobacter nodosus og sanering for ondartet klovsyge i tre danske fårebesætninger. DVT nr 8 sidor 28-34.

König U., Nyman A., Aspán A., Frosth S., Båverud V., Verdier KD., Averpil HB., and Holmström, A. (2010). Förekomst av fotröta hos slaktlamm i Sverige. Svensk Veterinärtidning nr 4 sidor 11-15.