For the most up-to-date list of my publications, please check my Google Scholar page.

I am always happy to share my work, so please contact me if you have any difficulties accessing my papers.

Research papers

Social Interactions in Viruses

  • Collective infectious units
    • Many viruses disperse as groups, inside ‘collective infectious units’. Although these structures appear across many different viruses, there are few ideas for why they are favoured over individual transmission. We modelled some evolutionary hypotheses that could drive the evolution of collective infectious units.
    • Leeks, A., Sanjuán, R. & West, S.A. 2019. The evolution of collective infectious units in viruses. Virus Research 265: 94–101.
  • Beneficial coinfection
    • Many viral infections show high levels of diversity, with many different variants of the same virus coexisting inside a host. This diversity presents an evolutionary problem: why don’t the faster-growing variants out-compete the slower-growing variants? We showed that diversity can be maintained if host cells infected by multiple different variants are more productive than cells infected by just one variant, a phenomenon that could be relatively common in RNA viruses.
    • Leeks, A., Segredo-Otero, E.A., Sanjuán, R. & West, S.A. 2018. Beneficial coinfection can promote within-host viral diversity. Virus Evol 4.

Theory of Mutualisms

  • Transmission & relatedness
    • Symbionts that transmit vertically (from parent to offspring) generally provide more help to their host than those that transmit horizontally (from adult host to adult host). Two main explanations have been proposed for this: firstly, vertical transmission aligns the fitness interests of host and symbiont; secondly, vertical transmission reduces mixing of symbiont lineages, increasing the genetic relatedness between symbionts sharing a host. We built a model in which both mechanisms could operate, and we showed that the second mechanism tends to overshadow the first mechanism.
    • Leeks, A., dos Santos, M. & West, S.A. 2019. Transmission, relatedness, and the evolution of cooperative symbionts. J Evol Biol jeb.13505.

Review Papers

  • The evolution of cheating in viruses
    • The success of many viruses depends upon cooperative interactions between viral genomes. However, whenever cooperation occurs, there is the potential for ‘cheats’ to exploit that cooperation. We suggest that: (1) the biology of viruses makes viral cooperation particularly susceptible to cheating; (2) cheats are common across a wide range of viruses, including viral entities that are already well studied, such as defective interfering genomes, and satellite viruses. Consequently, the evolutionary theory of cheating could help us understand and manipulate viral dynamics, while viruses also offer new opportunities to study the evolution of cheating.
    • Leeks, A., West, S.A. & Ghoul, M. 2021. The evolution of cheating in viruses. Nature Communications. 12: 6928.


  • Altruism in a virus
    • We wrote a short commentary on Domingo-Calap et al’s work showing that viral suppression of interferon release from infected cells is costly to individual viruses, but provides a group benefit. Consequently, we can understand why viruses have evolved to suppress interferon by applying the evolutionary concept of altruism.
    • Leeks, A. & West, S.A. 2019. Altruism in a virus. Nat Microbiol 4: 910–911.


My doctoral thesis is freely available here. The introduction and conclusion are otherwise unpublished and contain some commentary on the links between social evolution theory and virology.