History of Polio — From Ancient Egypt to the Last Two Countries

Polio is not a modern disease. An Egyptian stele carved around 1400 BCE shows a young priest with a withered, shortened leg and a walking staff — the earliest widely recognised depiction of what we now call poliomyelitis. For most of recorded history the disease was simply part of the background of childhood: a fever, then a limb that never worked again, with no explanation and no remedy.

Why epidemics arrived so late

One of the strangest facts about polio is that it became far more dangerous as societies became cleaner. In communities with poor sanitation, almost every infant met the virus while still protected by maternal antibodies, and most acquired lifelong immunity without ever becoming seriously ill. As sanitation improved across Europe and North America in the nineteenth century, that early exposure stopped happening — and the virus began meeting older children and adults whose nervous systems were far more vulnerable.

The result was the epidemic era. Summer after summer through the first half of the twentieth century, cities closed swimming pools and cinemas, parents kept children indoors, and hospitals filled with iron lungs for those whose breathing muscles had failed. Polio became one of the most feared diseases in the industrialised world precisely because it struck without warning in clean, prosperous neighbourhoods.

The two vaccines that changed everything

The breakthrough came in two stages. In 1955 Jonas Salk's inactivated polio vaccine — a killed-virus injection — was licensed after one of the largest field trials ever conducted. In 1961 Albert Sabin's oral polio vaccine followed: a live weakened virus given as drops, cheap to produce, easy to administer by mouth and capable of producing immunity in the gut, which is where poliovirus multiplies.

The oral vaccine is the reason mass campaigns became possible. It needs no syringe, no clinical training beyond a short course, and can be carried in a cold box down a mountain path or into a city street. Both vaccines are still in use today, and the polio FAQs explain where each one fits.

From national control to global eradication

Mass immunisation drove polio out of the Americas, Europe, the Western Pacific and eventually most of Asia and Africa. In 1988, with wild poliovirus still paralysing an estimated 350,000 children a year in 125 countries, the World Health Assembly committed to eradicating it outright. Wild type 2 was certified eradicated in 2015, wild type 3 in 2019. Only wild poliovirus type 1 remains — and only in two countries. The global polio page sets out how that effort is structured.

Polio in Pakistan

Pakistan has been fighting polio since before independence, but the organised national campaign dates from 1994. In the early 1990s the country recorded roughly 20,000 cases a year. By 2017 that had fallen to eight. The path since has not been a straight line — 147 cases in 2019, a single case in 2021, 74 in 2024, 31 in 2025 — but the long-run reduction is close to 99.8 per cent.

What remains is the hardest part of any eradication effort: the last chains of transmission, in the places and among the families that are most difficult to reach. The province-wise case record shows how that has played out year by year, and the eradication strategy explains what the programme is doing about it now.

A disease with no cure

It is worth restating the fact that underlies the entire history above: there is still no treatment that reverses polio paralysis. Physiotherapy, braces and surgery can improve function, but nerve cells destroyed by the virus do not regenerate. Every case of paralysis since 1955 has been, in principle, preventable — which is why the programme's message has never changed. Vaccinate every child, every time.