John Grewar

667 total citations
37 papers, 417 citations indexed

About

John Grewar is a scholar working on Agronomy and Crop Science, Ecology, Evolution, Behavior and Systematics and Infectious Diseases. According to data from OpenAlex, John Grewar has authored 37 papers receiving a total of 417 indexed citations (citations by other indexed papers that have themselves been cited), including 23 papers in Agronomy and Crop Science, 19 papers in Ecology, Evolution, Behavior and Systematics and 18 papers in Infectious Diseases. Recurrent topics in John Grewar's work include Animal Disease Management and Epidemiology (19 papers), Vector-Borne Animal Diseases (18 papers) and Viral Infections and Vectors (17 papers). John Grewar is often cited by papers focused on Animal Disease Management and Epidemiology (19 papers), Vector-Borne Animal Diseases (18 papers) and Viral Infections and Vectors (17 papers). John Grewar collaborates with scholars based in South Africa, United Kingdom and Australia. John Grewar's co-authors include Alan J. Guthrie, Graeme S. Cumming, Christine Moore, Célia Abolnik, Ν. James MacLachlan, Adriaan Olivier, Peter Coetzee, Hayley S. Clements, Danica Pollard and Marco Romito and has published in prestigious journals such as PLoS ONE, Journal of Dairy Science and Journal of Applied Ecology.

In The Last Decade

John Grewar

32 papers receiving 403 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
John Grewar South Africa 13 218 210 189 94 61 37 417
David Chavernac France 10 179 0.8× 222 1.1× 245 1.3× 91 1.0× 62 1.0× 20 408
Jacqueline Kasiiti Lichoti Kenya 10 112 0.5× 118 0.6× 120 0.6× 49 0.5× 35 0.6× 27 313
Victor Ngu Ngwa Cameroon 13 189 0.9× 176 0.8× 143 0.8× 117 1.2× 82 1.3× 32 462
José Fafetine Mozambique 16 356 1.6× 70 0.3× 197 1.0× 63 0.7× 118 1.9× 32 591
Antonello Di Nardo United Kingdom 18 221 1.0× 576 2.7× 535 2.8× 57 0.6× 50 0.8× 44 795
Carla Ippoliti Italy 15 314 1.4× 229 1.1× 228 1.2× 63 0.7× 240 3.9× 47 616
Anton Gerilovych Ukraine 12 166 0.8× 139 0.7× 104 0.6× 167 1.8× 35 0.6× 48 429
Sergei Khomenko Italy 7 91 0.4× 205 1.0× 155 0.8× 42 0.4× 54 0.9× 10 369
Yatinder S. Binepal Kenya 12 215 1.0× 66 0.3× 103 0.5× 190 2.0× 55 0.9× 21 466

Countries citing papers authored by John Grewar

Since Specialization
Citations

This map shows the geographic impact of John Grewar's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by John Grewar with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites John Grewar more than expected).

Fields of papers citing papers by John Grewar

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by John Grewar. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by John Grewar. The network helps show where John Grewar may publish in the future.

Co-authorship network of co-authors of John Grewar

This figure shows the co-authorship network connecting the top 25 collaborators of John Grewar. A scholar is included among the top collaborators of John Grewar based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with John Grewar. John Grewar is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Dijk, Jan van, et al.. (2025). Reasons to be fearful? Rising proportions of positive faecal worm egg counts among UK horses (2007–2023). Equine Veterinary Journal. 57(6). 1572–1583.
2.
Thompson, Peter N., et al.. (2025). A cross-sectional study of keratoconjunctivitis among dairy cattle farms subject to Mediterranean climatic conditions. Tropical Animal Health and Production. 57(3). 141–141.
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Henning, Joerg, et al.. (2023). Bacterial culture and susceptibility test results for clinical mastitis samples from Australia's subtropical dairy region. Journal of Dairy Science. 107(2). 1151–1163. 6 indexed citations
6.
Abolnik, Célia, et al.. (2023). The Molecular Epidemiology of Clade 2.3.4.4B H5N1 High Pathogenicity Avian Influenza in Southern Africa, 2021–2022. Viruses. 15(6). 1383–1383. 28 indexed citations
7.
Gorsich, Erin E., et al.. (2023). Modelling African horse sickness emergence and transmission in the South African control area using a deterministic metapopulation approach. PLoS Computational Biology. 19(9). e1011448–e1011448. 4 indexed citations
8.
Pollard, Danica & John Grewar. (2022). Cars dent, horse riders break: Analysis of police-recorded injury incidents involving ridden horses on public roads in Great Britain. Journal of Safety Research. 84. 86–98. 1 indexed citations
9.
Grewar, John, et al.. (2021). Modelling the factors affecting the probability for local rabies elimination by strategic control. PLoS neglected tropical diseases. 15(3). e0009236–e0009236. 3 indexed citations
10.
Abolnik, Célia, et al.. (2021). Experimental infection of ostriches with H7N1 low pathogenic and H5N8 clade 2.3.4.4B highly pathogenic influenza A viruses. Veterinary Microbiology. 263. 109251–109251. 3 indexed citations
11.
Grewar, John, et al.. (2021). An entry risk assessment of African horse sickness virus into the controlled area of South Africa through the legal movement of equids. PLoS ONE. 16(5). e0252117–e0252117. 12 indexed citations
12.
Porphyre, Thibaud & John Grewar. (2019). Assessing the potential of plains zebra to maintain African horse sickness in the Western Cape Province, South Africa. PLoS ONE. 14(10). e0222366–e0222366. 7 indexed citations
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Sergeant, E., et al.. (2016). Quantitative Risk Assessment for African Horse Sickness in Live Horses Exported from South Africa. PLoS ONE. 11(3). e0151757–e0151757. 17 indexed citations
16.
Koekemoer, Otto, John Grewar, Antoinette van Schalkwyk, et al.. (2015). Development of three triplex real-time reverse transcription PCR assays for the qualitative molecular typing of the nine serotypes of African horse sickness virus. Journal of Virological Methods. 223. 69–74. 19 indexed citations
17.
Grewar, John, et al.. (2015). Equine encephalosis in Thoroughbred foals on a South African stud farm. Onderstepoort Journal of Veterinary Research. 82(1). 966–966. 7 indexed citations
18.
Moore, Christine, Graeme S. Cumming, Jasper A. Slingsby, & John Grewar. (2014). Tracking Socioeconomic Vulnerability Using Network Analysis: Insights from an Avian Influenza Outbreak in an Ostrich Production Network. PLoS ONE. 9(1). e86973–e86973. 16 indexed citations
19.
Abolnik, Célia, et al.. (2012). Molecular Analysis of the 2011 HPAI H5N2 Outbreak in Ostriches, South Africa. Avian Diseases. 56(4s1). 865–879. 27 indexed citations
20.
Grewar, John, J. G. Allen, & Alan J. Guthrie. (2009). Annual ryegrass toxicity in Thoroughbred horses in Ceres in the Western Cape Province, South Africa. Journal of the South African Veterinary Association. 80(4). 220–223. 9 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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