Nigeria will likely eradicate polio by the end of 2019, according to WHO’s Strategic Advisory Group of Experts on Immunizations, also known as SAGE. Once the country reaches 3 years of being polio-free, only two countries — Afghanistan and Pakistan — will still have local transmission of the virus.
“The problem is that if we are not able to vaccinate as many children as possible, then there is no way of stopping the circulation of the wild virus and, therefore, the progression of the disease,” Alejandro Cravioto, MD, PhD, chair of SAGE, said in a press conference. “We did that in Nigeria in a situation that was also politically difficult in the northern parts of the country. But, [these parts were] able to be accessed, and children were vaccinated. For almost 3 years now, we haven’t had the isolation of a wild virus.”
Cravioto also mentioned that the group favored a global strategy to shift from oral vaccines to injectable vaccines in areas where vaccine-derived strains of polio are circulating, including the Democratic Republic of the Congo (DRC), Syria and Papua New Guinea. The shift to injectable polio vaccines is necessary in these areas because the combination of low levels of immunity against poliovirus and the use of the live, bivalent oral polio vaccine can result in infection.
“We hope that now that the supply of injectable polio vaccine has been ramped up, we can really access all the children who were not vaccinated because there was not enough vaccine to be able to really start controlling the circulation of the vaccine-derived viruses,” he said.
Kate O’Brien, MD, MPH, director of the department of immunization, vaccines and biologicals at WHO, added that maintaining a high level of vaccine coverage around the world is crucial to the eradication of the virus, which she said is “fighting for its life, and we are in the last stages of the fight.”
Maternal and infant immunization against Ebola
SAGE also discussed progress toward effectively vaccinating pregnant and lactating women, along with children aged 6 months and older, against Ebola by including them in ring vaccination strategies. Nearly 100,000 people have been vaccinated through this strategy in the DRC, where more than 1,000 cases of the infection have been reported.
“The ethics review committee of the DRC’s Ministry of Health decided some time ago to go ahead and vaccinate pregnant women, women who were lactating and small children given that this group seemed to be at risk or higher risk of becoming infected,” Cravioto said. “SAGE has endorsed this recommendation and made it clear that we recommend that these groups be part of the immunization process in ring vaccination, which we have also recommended.”
Future vaccine strategies for malaria
The committee members discussed plans to include malaria vaccines with routine immunizations but are waiting for the results of several pilot programs before they make a decision.
“SAGE welcomed with great enthusiasm the pilot programs that are about to begin in three countries in Africa: Ghana and Malawi in the coming weeks and Kenya thereafter,” O’Brien said. “We would like to note that the introduction of the RTS,S malaria vaccine would be a major public health landmark. This will be the first time that a malaria vaccine has ever been used in the routine immunization program and really should be recognized as a historic moment in public health and the fight against malaria, which has been a very difficult area to gain accelerated traction on.”
The group discussed a framework to evaluate the pilot programs, which they said could lead to broader recommendations of the vaccines. – by Katherine Bortz