The 1957 Pandemic — The Asian Flu

Newspaper article from 1957

The Asian Flu, as it is popularly called, began in the early months of 1957 and spread across the entire world within two years. An epidemic becomes a pandemic when the illness crosses many countries. The world only got wind of the outbreak in February; it was conjectured that it had started in late 1956, but China kept it quiet.

Influenza viruses are divided into four types — A, B, C, D. Type A viruses (including H1N1 and H2N2) are the ones that cause pandemics.

In February 1957, a new virus — H2N2 — had originated in China. It spread rapidly through Asia and the Middle East. People had not forgotten the Spanish Flu of 1918, which had infected about a third of the world's population and killed an estimated 50 million.

In late March and April 1957, microbiologist Maurice Hilleman — who developed more than 40 vaccines in his career — realized the US would face another pandemic if steps weren't taken quickly. American newspapers were reporting an outbreak in Hong Kong. One line caught his attention: "women carried glassy-eyed children tied to their backs," describing the long waiting lines for clinics.

Maurice Hilleman — the man who developed more than 40 vaccines

Hilleman read that 250,000 Hong Kong residents were receiving treatment for the flu. China's numbers could not be trusted; the true toll was probably higher. By April 17, the Times of London reported "an influenza epidemic has affected thousands of Hong Kong residents." By mid-May there were 100,000 cases in Taiwan, and over a million in India by June.

Details of the outbreak in India, 1957

News from the UK was grim: by June, many were infected, with symptoms of high fever, cough, and nosebleeds; the seriously ill succumbed to pneumonia. The virus reached India, where fatalities were less severe.

The day after reading the story, Hilleman sent a cable to an Army laboratory in Zama, Japan, asking the staff to investigate what was going on in Hong Kong. A medical officer found a US Navy member who had been infected in Hong Kong and sent the serviceman's samples back to Hilleman so he could study the virus.

Hilleman compared the sample against the serums available to him and discovered it was different from all past influenza strains. He sounded the alarm: if the US didn't act soon, the country could face a pandemic by September. By the time the fall wave arrived, a vaccine was ready — a feat that is estimated to have saved many lives. Worldwide, the 1957 pandemic still killed about 1.1 million people.

Sources: Emerging Infectious Diseases: The 1957 Pandemic, New York Times, April 17, 1957. Originally published April 2020.