Featured Research

from universities, journals, and other organizations

Polio: Mutated virus breaches vaccine protection

Date:
August 21, 2014
Source:
Universität Bonn
Summary:
Thanks to effective vaccination, polio is considered nearly eradicated. Each year only a few hundred people are stricken worldwide. However, scientists are reporting alarming findings: a mutated virus that was able to resist the vaccine protection to a considerable extent was found in victims of an outbreak in the Congo in 2010. The pathogen could also potentially have infected many people in Germany.

Polio vaccine (stock image). Scientists are reporting alarming findings: a mutated polio virus was able to resist vaccine protection.
Credit: © Sherry Yates / Fotolia

Thanks to effective vaccination, polio is considered nearly eradicated. Each year only a few hundred people are stricken worldwide. However, scientists of the University of Bonn, together with colleagues from Gabon, are reporting alarming findings: a mutated virus that was able to resist the vaccine protection to a considerable extent was found in victims of an outbreak in the Congo in 2010. The pathogen could also potentially have infected many people in Germany.  

The polio epidemic in the Congo in 2010 was especially serious. 445 people were verifiably infected, mostly young adults. The disease was fatal for 209 of them. This high mortality rate is surprising. Also important was the fact that many of those affected had apparently been vaccinated: Surveys indicated that half of the patients remembered having received the prescribed three vaccination dosages. To date the vaccination has been considered a highly effective weapon for containing the polioviruses that cause the disease.

"We isolated polio-viruses from the deceased and examined the viruses more closely," explains Dr. Jan Felix Drexler, who is in the meantime working in the Netherlands. He carried out the study during his employment at the Institute for Virology of the University Hospital of Bonn under the supervision of Prof. Christian Drosten, together with his colleagues from Gabon, Dr. Gilda Grard and Dr. Eric Leroy. "The pathogen carries a mutation that changes its form at a decisive point." The result: the antibodies induced by the vaccination can hardly block the mutated virus and render it harmless.

The researchers have examined the success with which the new pathogen evades the immune system. To this purpose, they tested, among others, blood samples from 34 medical students of the University of Bonn. All of them were vaccinated in childhood with the usual methods against polio. And very successfully, as an initial test showed: The antibodies in the blood of the test subjects had no problem combating "normal" polio viruses. The situation was different with the mutated virus; the immune reaction was much weaker here. "We estimate that one in five of our Bonn test subjects could have been infected by the new polio virus, perhaps even one in three," says Prof. Drosten.

Eradication possible

The World Health Organization (WHO) has undertaken the goal of eradicating the polio virus in coming years. The role model here is smallpox -- thanks to a consistent vaccination strategy, the earth has been classified as free of smallpox since 1980. The chances are principally good that something similar could succeed again: The polio virus can also only be transmitted from person to person. There are thus no pathogen reservoirs in animals from which the disease could spread repeatedly. Similar to with smallpox, the polio vaccines also offer extraordinary protection. This, however, does not apply when the virus mutates. "When such an altered pathogen encounters a population that has not been consistently vaccinated enough, then things get dangerous," the scientists warn.

The polio epidemic in the Congo was stopped with a massive vaccination program and hygiene measures. Even the current vaccines thus appear to be good enough to be effective when they are promptly and consistently administered. The new pathogen is nonetheless a warning: "We can't afford to sit back and do nothing," the scientists warn. "We need to further increase the vaccination rate and develop new, more potent vaccines. Only in this way do we have a chance of permanently vanquishing polio."


Story Source:

The above story is based on materials provided by Universität Bonn. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. F. Drexler, G. Grard, A. N. Lukashev, L. I. Kozlovskaya, S. Bottcher, G. Uslu, J. Reimerink, A. P. Gmyl, R. Taty-Taty, S. E. Lekana-Douki, D. Nkoghe, A. M. Eis-Hubinger, S. Diedrich, M. Koopmans, E. M. Leroy, C. Drosten. Robustness against serum neutralization of a poliovirus type 1 from a lethal epidemic of poliomyelitis in the Republic of Congo in 2010. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1323502111

Cite This Page:

Universität Bonn. "Polio: Mutated virus breaches vaccine protection." ScienceDaily. ScienceDaily, 21 August 2014. <www.sciencedaily.com/releases/2014/08/140821115706.htm>.
Universität Bonn. (2014, August 21). Polio: Mutated virus breaches vaccine protection. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2014/08/140821115706.htm
Universität Bonn. "Polio: Mutated virus breaches vaccine protection." ScienceDaily. www.sciencedaily.com/releases/2014/08/140821115706.htm (accessed October 22, 2014).

Share This



More Health & Medicine News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) — Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) — Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
US to Track Everyone Coming from Ebola Nations

US to Track Everyone Coming from Ebola Nations

AP (Oct. 22, 2014) — Stepping up their vigilance against Ebola, federal authorities said Wednesday that everyone traveling into the US from Ebola-stricken nations will be monitored for symptoms for 21 days. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Doctors Help Paralysed Man Walk Again, Patient in Disbelief

Doctors Help Paralysed Man Walk Again, Patient in Disbelief

AFP (Oct. 22, 2014) — Polish doctors describe how they helped a paralysed man walk again, with the patient in disbelief at the return of sensation to his legs. Duration: 1:04 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins