This month will mark the last time that one type of polio will ever be transmitted to a child. 2016 might also be the year that marks the overall end of the polio era, says Sanofi
By the end of April, poliovirus type 2 will disappear completely from the planet. A few samples will be kept in highly secure laboratories – to protect against any future threat – but it will be the first of the three polio viruses to become effectively extinct. The remaining two polioviruses should follow it into the history books before the end of the decade, maybe even before the end of the year.
“I am sure we will end polio and there’s a very good chance that history will record 2016 as the year we won the fight,” said Olivier Charmeil, the president and CEO of Sanofi Pasteur, a large producer of all kinds of polio vaccines.
The Sanofi Pasteur CEO’s enthusiasm is shared by many global experts who dare to hope that 2016 will be the year in which the world sees its last ever case of any kind of transmission of a naturally-occurring poliovirus.
In January of this year, Dr William Moss, head of epidemiology at the International Vaccine Access Center at Johns Hopkins told Global Citizen: "I'm going to be an optimist and say the big public health story of 2016 will be the last case of polio in the world.”
In the first quarter of 2016, there were only nine cases of polio down from 21 in the first quarter of last year. All were in Pakistan and Afghanistan. Last year saw 74 cases worldwide, the fewest in recorded history.
Africa saw its last case of wild polio almost two years ago and it seems almost certain to be declared polio free in summer 2017. Type 2 poliovirus has been waning since the last century: the last case of a wild infection from wild poliovirus type 2 (WPV2) was seen in 1999. However, the virus has lived on, in a very weakened form, in the live oral polio vaccine (OPV). Now, in a move covering 145 countries, the WHO and its partners are carrying out a plan to remove the type 2 virus from oral polio vaccines. During the month of April, every country will switch from oral polio vaccine containing all three types of the virus to a vaccine containing only types 1 and 3.
Every country has introduced or is introducing at least one dose of injectable inactivated polio vaccine (IPV). IPV contains only killed virus so it can never cause a case of disease. It protects against all three subtypes. If every child receives at least one dose of IPV, she will get some protection from all the polio subtypes.
IPV is the only polio vaccine that has been used in Europe and North America for decades. A ground breaking public-private agreement in 2014 has made it accessible for the whole world.
After polio has been eradicated, IPV will continue to be used to protect against any future outbreak caused by intentional release or some occurrence that we cannot foresee.
Fifteen years ago, many thought that polio eradication was a hopeless quest. OPV was the tool which had reduced polio cases from 1,000 a day in 1988 to almost one a day by the turn of the century. However, at the beginning of this century, it became clear that communities in which only some children received OPV were vulnerable to outbreaks of vaccine-derived polio.
Children who had just been vaccinated could occasionally infect those who had not. The political will to end polio also seemed to be waning. Some said that the world should abandon the effort. There were almost 2,000 cases in 2002, four times the number that there had been the year before.
The coordinated Global Polio Eradication Initiative plotted a way through these difficulties. The breakthrough required using vaccines intelligently and phasing in IPV while OPV was still used to end endemic transmission.
Sanofi Pasteur is the world’s largest producer of IPV. It concluded an agreement in 2014 with the Bill & Melinda Gates Foundation supporting Gavi, UNICEF and WHO in making IPV available in every country. Before the agreement was even signed, Sanofi Pasteur ramped up production to meet global need. A four-year program of expanding production capacity was due to end in mid-2015. The company is producing two thirds more IPV this year than last year, for the 124 countries which introduced IPV starting in 2014.
“We will do whatever it takes to help the world eradicate polio,” said Charmeil. “The lessons of the early part of this decade are that polio will seize any opportunity to re-establish itself but I really do think that, this time, it is finished. Generations to come will only encounter polio in a history book.”