MPI's director of food safety and regulation, Paul Dansted said while there hasn't been a human case reported for months, it's introducing stricter rules which will see farmers testing flocks more often.
"What we're concerned about at this stage is - while we in the industry have worked really hard to stamp out from identified locations - what's become very clear to us is there weren't any rules in place. And the industry is really quite vulnerable to re-infection of this particular bug.
"We've actually seen that happen a couple of times where farms have eliminated it. And then soon after they get re-infected. So what we're wanting to do is put rules that work for the industry, right across the industry to protect all those operators and ultimately the consumer."
Dansted said all commercial chicken farms will be required to test their flocks more often - how often depends on the size of the flock.
He said despite the new controls consumers should always practice good kitchen hygiene to reduce the risk of getting the strain.
Executive Director of The Poultry Industry Association, Michael Brooks said the sector has worked closely with MPI on the new controls.
"The wider testing will give us confidence as to whether or not there is Salmonella Enteritis on farms, MPI has been testing the largest 25 farms in the country which have all come back negative but the new rules will see everyone tested.
"It's a difficult situation because the strain can be in the environment - you can get five negative tests and then the sixth time it's suddenly positive, we've never had the strain here before and we want to ensure we can get back to that status."
Brooks said the additional testing and the cost of it is something farmers are concerned about.
"You can get a straightforward test which tells you whether it's salmonella but then if you need to say what subtype it is like Salmonella Enteritidis that can cost hundreds of dollars.
"So yeah it will add another cost, especially for our smaller free-range farms."
- RNZ
