Pandemic of 1918 ‘helped combat threat of swine flu’

WHEN swine flu first emerged in Britain in 2009, public health experts predicted up to 65,000 people would die, yet the true death toll turned out to be fewer than 400.

Now an international study has suggested that the epidemic was so mild because many people were already carrying some protective immunity when the virus arrived.

A research team led by the Robert Koch Institute in Berlin found both the Spanish flu of 1918 and the seasonal flu virus that went on circulating after the pandemic carried similar hemagglutinins – a type of protein that allows the virus to bind to human cells.

The team said that the 1918 pandemic strain entered the pig population and

‘Previous immunity to flu is likely to have reduced the burden in the elderly age group in 2009’

remained there before finding a way back into humans in 2009.

But it also evolved into less deadly flu strains which were caught by many people, leaving a legacy of protection.

Dr Thorsten Wolff said: “People who are vaccinated these days with an H1N1 pandemic component, develop antibodies that cross react with 1918 hemagglutinin. So we are not as naive to a 1918 virus as people were more than 100 years ago.”

He said previous immunity was “likely to have reduced the burden in the elderly age group in 2009”.

Researchers analysed 13 lung specimens from different individuals stored in historical archives in Germany and Austria, collected between 1901 and 1931, including six samples from 1918 and 1919.

Spanish flu infected a fifth of the world’s population and killed up to 100 million people.

The findings were published in the journal Nature Communications.