Bill Gates has warned that the world's emergency response systems are not yet strong enough to cope with a deadly flu epidemic - one he is crossing his fingers will not arise in the next 10 years.

The Microsoft co-founder said the Ebola and Zika virus crises showed that global health infrastructure had room for improvement, the BBC reported.

The philanthropic Bill and Melinda Gates Foundation counts tackling disease, including pneumonia, malaria and polio, among its objectives.

Mr Gates told Dame Sally Davies, the Chief Medical Officer for England, on the Today programme:

"When we've seen Ebola or even now Zika, we realise we still haven't done enough.

"Our ability to create new drugs and vaccines quickly where we have an emerging disease, our emergency response system where we get people in and try and stop these epidemics - we don't have a strong enough system."

He added: "I cross my fingers all the time that some epidemic like a big flu doesn't come along in the next 10 years.