The present disclosure provides, among other things, a vaccine composition that includes a squalene nanoemulsion (SNE) adjuvant and HPV virus-like particles (VLPs) of at least one type of human papillomavirus (HPV) selected from the group consisting of HPV types: 6, 11, 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 55, 56, 58, 59, 66, 68, 73, and 82.

There is described a process for production of metal-coated virus particles or metallic nanoparticles, said process comprising admixing virus particles with plant material with reducing power and a metal salt, wherein the process can be provided in planta or ex planta and the virus particles aid the production of the metal-coated virus particles or metallic nanoparticles.