WIKIMEDIA, GRAHAM BEARDSPolio is nearly eradicated. But vaccine campaigns will continue in case, for example, some remaining infections go undetected. With the current technology, the need to continue vaccinations poses a challenge to a poliovirus-free world because “the only way you can make [vaccines] at the moment is using a live virus,” virologist Andrew Macadam at the U.K.’s National Institute for Biological Standards and Control, told The Scientist. The oral polio vaccine (OPV) contains live, attenuated virus; the inactivated polio vaccine (IPV) is made by growing, then killing, virulent virus. Both of these vaccines could cause outbreaks, through reversion of OPV to a virulent form or through leakage of live virus from an IPV production plant, Macadam explained.
To circumvent these problems, Macadam and colleagues are working to develop new vaccines that contain no virus at all. These consist of empty viral capsids, the viruses’ protein coats, called virus-like particles (VLPs). In a study published today (January 19) in PLOS Pathogens, the team reported having created capsid-based vaccines that are stable and, in rodent experiments, worked as well as IPVs in protecting against polio.
The study “opens up the possibility of not having to use virus to produce a virus-like particle which is noninfectious” said Olen Kew, the national poliovirus containment coordinator at the US Centers for Disease Control and Prevention, who was not involved in the research. “The facilities which handle by far the largest amounts of poliovirus are the vaccine producers,” ...
