Polio: a VaccinesWork guide
This week, VaccinesWork is shining its spotlight on polio, a disease the world is on the verge of vanquishing. Stay with us to learn about the people, and plans, fuelling that final furlong.
- 21 October 2024
- by Maya Prabhu , James Fulker
There are many good ways to measure the almost there of the global drive to eradicate poliomyelitis.
Cases of wild polio have dropped 99% since 1988, when the Global Polio Eradication Initiative (GPEI) was established. Two out of three strains of the wild-type virus have been eradicated. The remaining strain, termed wild poliovirus type 1 (WPV1), inhabits a drastically shrunken geography, endemic in just Afghanistan and Pakistan.
While in 1988 an estimated 350,000 people in 125 countries fell ill with the paralysing disease, last year, our two remaining endemic countries recorded just 12 cases of WPV1-linked disease between them. Conversely, 20 million more people are walking today who wouldn’t otherwise have been.
Vaccines – a tag-team of them – have played in integral role in getting us this close to the end, and they’ll get us the rest of the way to eradication too. But the final percent will take an uphill push.
That’s because the poliovirus forces a high standard for safety: according to the World Health Organization, the threshold for herd immunity is 80%.
And wild-type polio virus isn’t the only paralysing threat out there. Variant polio, which crops up in rare cases when the weakened, safe strain of the virus in the oral vaccine has too much opportunity to spread unchecked, mutating along the way – in other words, in places where vaccine coverage is low in the first place – is also capable of seeding outbreaks.
When polio begins to spread, it travels stealthily: just one in 200 cases is symptomatic. That makes the virus adept at exploiting even narrow cracks in a population’s immunity.
Those cracks tend to gape amid war and disaster, inviting misfortune to compound misfortune. It’s no coincidence that cases of polio have cropped up among the besieged children of Gaza, in bombarded Ukraine, in troubled northern Nigeria, and in Afghanistan.
Any outbreak, anywhere, is a fire that can throw a spark. In 2022, a toddler in Lilongwe fell ill with WPV1 – Malawi’s first case in decades. Genetic analysis of the virus proved it was related to a strain traceable to Sindh province, Pakistan, in 2019. Neither the child nor her family had travelled.
There’s really only one solution: the cracks need closing. That requires both expertise and financial resources. Gavi and its partners in GPEI know how to get the work done – but both Gavi and GPEI need funding to do it.
Stick with us this week to read more dispatches from the end-zone of eradication. Until then, here are some of our favourite polio stories from the archive.
- The Editors
The endgame: What will it take to eradicate polio?
Polio cases are down from hundreds of thousands every year in the 1980s to just a few hundred today. We are close to making polio the second human disease to be eradicated, but what will it take to finally consign this killer disease to the history books?
Wild polio’s return to Africa: How the GPEI stopped an outbreak from becoming an inferno
In February 2022, a year and a half after the continent was declared free of indigenous poliovirus, a case surfaced in south-eastern Africa. The circumstances that proved that it’s not over until it’s over everywhere.
Motorbike-riding polio worker ruffles feathers and saves lives in rural Pakistan
Amina Khaskheli discovered she can reach more kids on two wheels than on two feet – so that’s what she’s doing. If the sight of her on her bike has upset some conservative onlookers, it has also inspired more than a few young girls.
“Reaching the unreached” in one of the last strongholds of poliovirus
In Pakistan’s most polio-troubled region, a new strategy sees encouraging successes.
The iron lung
Before 1955, when a vaccine first made polio a preventable illness, the paralysing disease had to be treated. For many, the best option was the iron lung, a device that came to symbolise an era of anxiety in mid-20th century America.
This article was originally published on VaccinesWork