Gert van der Hoek
In Memoriam - Editor, Senior Moderator
Live Virus Used In Polio Vaccine Can Evolve And Infect, Warns TAU Researcher
09 Nov 2011
Health professionals and researchers across the globe believe they are on the verge of eradicating polio, a devastating virus which can lead to paralysis and death. Despite successful eradication in most countries, there are still four countries where the virus is considered endemic - and many more in which the virus still lurks.
Dr. Lester Shulman of Tel Aviv University's Sackler Faculty of Medicine and the Israeli Ministry of Health has spent years tracking isolated cases of live poliovirus infections, often discovered in countries that are supposedly polio-free. When the live-virus version of the vaccine, called Oral Polio Vaccine (OPV) evolves, he says, it can act like wild poliovirus and continue the threat of contagion.
Medical professionals widely believe that after the wild virus is eradicated, resources dedicated to polio immunization can be redirected. But this isn't so, he says. He recommends that public health agencies take a three-pronged approach: Vaccination policies to maintain "herd immunity" (a 95 percent immunization rate for polio) should be maintained to prevent the spread of wild and evolved vaccine strains of the virus; environmental surveillance of sewage systems should continue; and a switch to Inactivated Polio Vaccine (IPV) instead of OPV should be implemented.
Dr. Shulman's research was recently published in PLoS ONE. He has also been invited as an informal expert to the World Health Organization's annual meeting on polio this fall.
Read more - medicalnewstoday
Full article :Neurovirulent Vaccine-Derived Polioviruses in Sewage from Highly Immune Populations - PlosOne
09 Nov 2011
Health professionals and researchers across the globe believe they are on the verge of eradicating polio, a devastating virus which can lead to paralysis and death. Despite successful eradication in most countries, there are still four countries where the virus is considered endemic - and many more in which the virus still lurks.
Dr. Lester Shulman of Tel Aviv University's Sackler Faculty of Medicine and the Israeli Ministry of Health has spent years tracking isolated cases of live poliovirus infections, often discovered in countries that are supposedly polio-free. When the live-virus version of the vaccine, called Oral Polio Vaccine (OPV) evolves, he says, it can act like wild poliovirus and continue the threat of contagion.
Medical professionals widely believe that after the wild virus is eradicated, resources dedicated to polio immunization can be redirected. But this isn't so, he says. He recommends that public health agencies take a three-pronged approach: Vaccination policies to maintain "herd immunity" (a 95 percent immunization rate for polio) should be maintained to prevent the spread of wild and evolved vaccine strains of the virus; environmental surveillance of sewage systems should continue; and a switch to Inactivated Polio Vaccine (IPV) instead of OPV should be implemented.
Dr. Shulman's research was recently published in PLoS ONE. He has also been invited as an informal expert to the World Health Organization's annual meeting on polio this fall.
Read more - medicalnewstoday
Full article :Neurovirulent Vaccine-Derived Polioviruses in Sewage from Highly Immune Populations - PlosOne