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Hello, this is Six Minute English from BBC Learning English, I'm Neil.
And I'm Georgina.
Covid-19 has changed everyday life for people in countries around the world,
but coronavirus wasn't the first pandemic to cause mass sickness and disrupt daily life.
Between 2002 and 2004, an outbreak of the disease known as SARS or severe acute respiratory syndrome caused hundreds of deaths in southern China before spreading to other parts of the world.
The virus that caused SARS survived by mutating, changing as it reproduced itself in the bodies of infected people, and this caused the virus to create strains, slight variations of the original.
Covid-19, the disease caused by the strain of the original SARS virus we are experiencing now,
has been called SARS-2.
In this program, we'll be looking at the origins of Covid-19 and hearing new evidence about the scale of the threat we face from the disease.
And of course, we'll be learning some new vocabulary as well.
But first, it's time for our quiz question.
We know that white blood cells make up part of the immune system our body needs to fight infectious diseases
like Covid-19, but how many white blood cells per microlitre does the average adult human need?
Is it A, 7000, B, 17,000 or C, 70,000?
In that case, I'd say more is better, so C,
70,000.
Okay, we'll find out the answer at the end of the program.
Now, Georgina,