How well do you know how the world got better?

Vaccines

A 2024 study summarised by the WHO credited immunization with about 154 million lives over 50 years, more than any other single intervention measured.

Alexander Fleming

Alexander Fleming noticed a mould killing bacteria on a lab plate in 1928. Howard Florey and Ernst Chain later turned it into a usable drug.

154 million

The figure is about 154 million lives from 1974 to 2024, the equivalent of six lives every minute, with about 101 million of them infants.

Oral rehydration therapy

Oral rehydration therapy treats the dehydration caused by diarrhoea. The glucose lets the gut absorb water and salt even during severe illness. It may have saved more than 70 million children.

Smallpox

Smallpox, which killed about 300 million people in the 20th century alone, was declared eradicated in 1980. It remains the only human disease ever eradicated.

Banting and Best

Frederick Banting and Charles Best, with James Collip and J.J.R. Macleod, isolated insulin in Toronto in 1921 to 1922. The first patient treated was 14-year-old Leonard Thompson.

About half the world

Synthetic nitrogen fertilizer supports roughly half of the global population, about 48 percent as of 2008. Without it, today's food supply could not feed everyone.

Insecticide-treated bed nets

A 2015 Nature study found that of an estimated 663 million malaria cases averted, insecticide-treated bed nets were the single largest contributor, at 68 percent.

Jonas Salk

Jonas Salk's injected vaccine was declared safe and effective in 1955. He never patented it. Albert Sabin later developed the oral vaccine used in global eradication.

Over 99 percent

The WHO reports wild poliovirus cases have fallen by over 99 percent since 1988, from an estimated 350,000 a year to a handful, in just two countries.

Cowpox

Jenner noticed milkmaids who caught mild cowpox seemed protected from deadly smallpox. The word vaccine comes from vacca, Latin for cow.

About 43 percent

Economists Cutler and Miller calculated clean water was responsible for about 43 percent of the total fall in death rates across 13 US cities from 1900 to 1936.

1978

Louise Brown, the first baby conceived through in vitro fertilisation, was born on 25 July 1978. Millions of IVF births have followed.

Surgical anaesthesia

The public demonstration of ether anaesthesia at Massachusetts General Hospital, later called Ether Day, opened the era of painless surgery.

About 4 percent

The global under-five mortality rate has fallen from about 42.8 percent in 1800 to about 3.7 percent today, its lowest level ever recorded.

More than halved

The share of the world in extreme poverty has more than halved since 1990, one of the largest improvements in human living standards ever recorded.