Molecular determinants of the ratio of inert to infectious virus particles Review uri icon


MeSH Major

  • Virion
  • Virus Diseases


  • The ratio of virus particles to infectious units is a classic measurement in virology and ranges widely from several million to below 10 for different viruses. Much evidence suggests a distinction be made between infectious and infecting particles or virions: out of many potentially infectious virions, few infect under regular experimental conditions, largely because of diffusion barriers. Still, some virions are inert from the start; others become defective through decay. And with increasing cell- and molecular-biological knowledge of each step in the replicative cycle for different viruses, it emerges that many processes entail considerable losses of potential viral infectivity. Furthermore, all-or-nothing assumptions about virion infectivity are flawed and should be replaced by descriptions that allow for spectra of infectious propensities. A more realistic understanding of the infectivity of individual virions has both practical and theoretical implications for virus neutralization, vaccine research, antiviral therapy, and the use of viral vectors.

publication date

  • January 2015



  • Review



  • eng

PubMed Central ID

  • PMC4724431

Digital Object Identifier (DOI)

  • 10.1016/bs.pmbts.2014.10.012

PubMed ID

  • 25595808

Additional Document Info

start page

  • 285

end page

  • 326


  • 129