The US firm has been boosting its stockpiles to ensure a minimum of six weeks’ additional emergency supplies, following the guidance given by the UK government in August.

MSD, known as Merck & Co in the US, runs the UK’s biggest animal health business, in Milton Keynes and a human health business in Hoddeson.

The US firm has been boosting its stockpiles to ensure a minimum of six weeks’ additional emergency supplies, following the guidance given by the UK government in August.

MSD, known as Merck & Co in the US, runs the UK’s biggest animal health business, in Milton Keynes and a human health business in Hoddeson.