A vaccine resistant mutation of the poliovirus was the cause of the major 2010 polio outbreak in DR Congo
Research published in the scientific journal ‘Proceedings of the National Academy of Sciences‘ has shown that a mutated strain of the poliovirus was responsible for a 2010 outbreak in the Democratic Republic of Congo, which claimed 209 lives. It was initially suspected that the outbreak occurred as a result of low levels of immunisation against the virus, however, research led by Dr.Christian Drosten at the University of Bonn has revealed that the viral strain responsible has evolved a mutation that can resist the immune response elicited by the polio vaccine.
The 2010 DRC outbreak was unique as it had a high fatality rate. The outbreak also affected mainly adults, whereas usually, it affects children under five.
To further investigate the cause of the outbreak, researchers at the University of Bonn sequenced the virus strain that was responsible for the outbreak. What the researchers found was that the virus strain had two mutations which altered the viruses structure, making it difficult for antibodies to bind to it.
Other factors that could have caused the outbreak to be even worse include overpopulation and conditions of poor hygiene.
What is worrying about this occurrence is that populations that may have developed immunity to older strains could become affected by new, mutated strains in other regions of the world.
Read more about it here: Mutant poliovirus caused Republic of Congo outbreak in 2010