Because matter: Combining vaccines could offer longevity.
Oral polio vaccines, delivered in droplet form, have reduced polio cases by more than 99 percent in recent decades. But because the drops contain live viruses – detectable in the excrement of children receiving the vaccine – the virus can spread and cause new infections in countries with poor sanitation. The new vaccine will not have this problem.
« Today, in 2023, more children are paralyzed by circulating vaccine-derived polio than by wild-type polio, » he said. Dr James Campbella pediatric infectious disease expert at the University of Maryland School of Medicine who studies vaccine development.
He called Gavi’s approval an « important step » to crack down on the virus globally because it will give children in low- and middle-income countries access to a product that pediatricians in the United States and Europe have long been offering.
The injection is also expected to help prevent infections due to its logistical ease. Because the polio vaccine will be packaged in a combination product that has already been distributed to children, scientists say countries that use it will be less likely to see a resurgence of polio once oral vaccines are phased out.
Background: Polio has remaining strongholds in Afghanistan and Pakistan.
Poliomyelitis, officially known as poliomyelitis, is a highly infectious viral disease transmitted mainly through feces in places with poor sanitation. The virus multiplies in the intestines and invades the nervous system, causing paralysis. Even a single existing case is problematic, experts say, because it could lead to a global resurgence.
The United States has long used an inactivated polio vaccine, or IPV, instead of oral drops, and Gavi has been helping low-income countries buy it for the past 10 years. But the new six-in-one vaccine, called a hexavalent, will also protect children from hepatitis B, Haemophilus influenzae, tetanus, diphtheria and whooping cough.
Adding polio protection to the current five-component vaccine will drive up its costs, but public health officials say the move is still cost-effective. Overall less vaccine doses it will help decrease petty expenses that add up, including syringes, serum coolers, and appointments with healthcare professionals.
What’s next: A global rollout is on the horizon.
Countries served by Gavi will now be able to apply for funding for the vaccine, which could be available as early as 2024. It is given in three doses within the first few months of life – plus a subsequent booster dose before age 2 – and UNICEF has estimated that the global market for the new vaccine could reach 100 million doses per year by 2030.