1968: a placid pandemic
The 1968 flu was milder still than the 1957 strain, but even this bug killed around 1 million people worldwide.
The virus was very like the 1957 strain - it also started life in China, when a bird-flu virus merged with a human flu strain.
Vaccine production failed to meet demand yet again.
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Aquatic wild birds are a constant carrier of many flu strains. They spread viruses to domestic birds like chickens and ducks.
Image: VLA |
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