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The Hong Kong Flu, the Long-Forgotten Pandemic (1968–1970)
Between 1968 and 1970, a new influenza virus gripped the world. The Hong Kong flu spread like wildfire around the world and was initially highly underestimated. The flu had a relatively low mortality rate, yet one to four million people died from this virus worldwide. What happened during this pandemic?
The origin of the Hong Kong flu virus goes back to 1957. That was the year of the Asian flu outbreak, a bird flu virus believed to have been spread by pigs that killed at least one million people worldwide for over a year. Pregnant women and elderly people with heart and lung diseases were at the greatest risk of death. In the years following this pandemic, the Asian flu continued as common and less dangerous winter flu, until in 1968 a hybrid variant of this flu virus and the bird flu was created: Hong Kong flu.
The beginning of the pandemic
The first case of the new flu virus was detected in Hong Kong on 13 July 1968, after health authorities in Hong Kong had already noticed earlier that month that more and more people were suffering from unexplained flu symptoms. Common complaints were fever, headache, muscle aches, sore throat, runny nose, and coughing, lasting on average between four and six days. But in some cases, these symptoms developed into more serious complaints such as pneumonia. The first case was identified in Hong Kong, hence the name of the flu virus, but it is likely that the virus originated in China and spread to Hong Kong first. At the time of the outbreak, Hong Kong had a population density of 6,000 people per square kilometre, which meant that the highly contagious flu virus spread through the region very quickly. By the end of July, some 500,000 people had been infected, about 15% of the population.
At the end of July 1968, the first reports of outbreaks in other countries in South-East Asia also came out. The number of infections grew rapidly in Vietnam and Singapore, among others, followed by India and the Philippines. Despite the Asian flu pandemic of 1957, people were no better prepared for an epidemic of that scale. It was the Times that was the first to sound the alarm about this new…
