How do eggs protect us from flu?

Each year up to 650,000 people die around the world from flu and five million become severely ill, according to the World Health Organisation.

Liverpool is home to the UK’s biggest flu vaccine manufacturing site, where 50 million doses are made each year using hen eggs.

Seqirus provides vaccines to countries as far afield as Australia and New Zealand.

Lesley Day takes a look at how eggs are used to protect people against flu.