The FSA has announced it is now checking whether infected meat had been introduced into the food chain, although it is continuing to reassure consumers poultry meat is safe to eat.
Up until this weekend, poultry sales had remained largely unaffected, with most retailers and suppliers in the sector describing sales as remaining steady. However Tesco has reported a slight drop in sales, and Sainsbury's said sales had fallen by 10%.
However, one industry insider said the weekend would prove the main testing ground as shoppers head to the supermarkets.
Some point to the fact that the outbreak has been focused on just one widely recognised brand and purely on turkey, leaving other poultry, such as chicken unscathed.
In the meantime, investigations are continuing into the source of the outbreak after Defra vets revealed the preliminary tests showed the viruses in Suffolk and the recent outbreaks in Hungary may well be identical.
Bernard Matthews has a processing plant in Sarvar, in Hungary - about 160 miles away from the infected area, Szentes.
However, the company insists there was no suggestion of any infection in its turkeys in Hungary.
Commercial director Bart Dalla Mura told the BBC he would be "very surprised" if Hungary turned out to be the source of infection.