From History extra by Laura Spinney
On 28 September 1918, a Spanish newspaper gave its readers a short lesson on influenza. “The agent responsible for this infection,” it explained, “is the Pfeiffer’s bacillus, which is extremely tiny and visible only by means of a microscope.”
The explanation was timely, because the world was in the grip of the most vicious flu pandemic on record – but it was also wrong: flu is caused by a virus. Unfortunately, it wasn’t just one Spanish newspaper that had misidentified the causative agent of the disease. The idea that flu was caused by a bacillus, or bacterium, was accepted by the most eminent scientists of the day, who would find themselves almost entirely helpless in the face of the scourge. Between the first recorded case in March 1918 and the last in March 1920, an estimated 50 million people died, though some experts suggest that the total might actually have been twice that number. The ‘Spanish flu’ killed more than the First World War, possibly more even than the Second World War – indeed, perhaps more than both put together.
The pandemic struck at a critical juncture in the evolution of understanding of infectious disease. Well into the 19th century, epidemics were considered acts of god – a notion that dated back to the Middle Ages. Bacteria were first observed in the 17th century, but initially weren’t connected with human illnesses. In the late 1850s the French biologist Louis Pasteur made the connection between micro-organisms and disease, and from a couple of decades later German microbiologist Robert Koch furthered modern concepts of infectious disease. ‘Germ theory’ was disseminated far and wide, slowly replacing more fatalistic ideas.
Categories: History of Medicine