History Today: How Alexander Fleming discovered Penicillin

Today, antibiotics are prescribed by doctors for all sorts of bacterial infections ranging from Urinary Tract Infections (UTIs) to strep throat to even some skin infections. So, it can be hard to imagine a time when antibiotics did not exist. That changed on September 3, 1928, with the discovery of penicillin, the world’s first antibiotic.

If you are a history geek who loves to learn about important events from the past, Firstpost Explainers’ ongoing series, History Today , will be your one-stop destination to explore key events.

In 2004, one of the most tragic hostage situations in modern times came to a violent end in Beslan, a small town in Russia. Armed terrorists had taken more than 1,100 people, including children, teachers and parents hostage in the school’s gymnasium.

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Here is all that took place on this day across the world.

Alexander Fleming discovered penicillin

One of the major breakthroughs in the history of medicine took place on September 3, 1928, when Scottish bacteriologist Alexander Fleming discovered penicillin. It became the world’s first true antibiotic.

The discovery happened by chance in his laboratory at St Mary’s Hospital in London, where Fleming noticed that a mould called Penicillium notatum had contaminated one of his petri dishes containing Staphylococcus bacteria. To his surprise, the mould had killed or prevented the growth of the surrounding bacteria.

This observation marked the birth of antibiotics, although it took over a decade for penicillin to be developed into a usable drug. In a paper published in 1929, he documented his findings and noted its potential as a powerful antibacterial agent. However, he struggled to isolate and purify the substance in large quantities, and his discovery went largely unnoticed by the scientific community for over a decade.

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It was in the early 1940s when scientists Howard Florey, Ernst Chain, and their team at Oxford University purified and mass-produced it. With support from the United States and Britain during World War II, penicillin was manufactured on a large scale, saving countless lives by treating infected wounds, pneumonia, and other bacterial diseases among soldiers.

Fleming, Florey, and Chain were jointly awarded the Nobel Prize in Physiology or Medicine in 1945, recognising their contribution to one of the greatest medical discoveries of the 20th century.

Russian school siege came to an end

A horrific three-day siege at a school in the Russian town of Beslan in North Ossetia came to an end in 2004. The crisis began on September 1 when heavily armed terrorists stormed School Number One, taking more than 1,100 people hostage. The hostages included hundreds of children, teachers, and parents. The attackers, linked to separatist groups from Chechnya, demanded Russian troop withdrawals from the region and independence for Chechnya.

For three days, the hostages were crowded into the school gymnasium, enduring inhumane conditions as they were kept without food, water, or medical aid. Explosives were strung around the building, which heightened the risk of mass casualties. The negotiations remained tense, and little progress was made as Russian authorities struggled to contain the crisis.

It was on September 3 that the situation escalated catastrophically. Explosions inside the gymnasium, reportedly triggered by unknown causes, led to chaos. Hostages attempted to flee, while militants opened fire. Through it all, Russian special forces stormed the building in a fierce battle, supported by tanks and helicopters. By the time the siege ended, the school lay in ruins, while the outcome was devastating - over 330 people were killed, with over half of them children. Hundreds of others were injured. The tragedy shocked the world and highlighted the brutal consequences of terrorism.

The Beslan school siege left deep scars in Russia, sparking national mourning, outrage, and renewed debate over counterterrorism measures. Critics questioned the authorities’ handling of the crisis, citing a lack of transparency and preparedness.

This Day, That Year

• In 1971, Qatar officially became independent from the United Kingdom.

• Labour Day was celebrated as a legal holiday in the United States for the first time on this day in 1894.

• In 1783, the Treaty of Paris was signed between Britain and the United States.