Director-General of Health, Dr Ashley Bloomfield, has asked the Whanganui District Health Board to ramp up Covid-19 testing, despite the low number of cases in the area.
So far, seven people have tested positive for the coronavirus - all of them recently returnedfrom overseas.
WDHB has one of the lowest testing rates in the country but says about a third of the people showing up at its assessment centres are now being swabbed.
Bloomfield wants test numbers across the country to increase over the next two weeks to make sure there are no cases of community transmission that have been missed and said he had asked the WDHB to increase the number of tests.
WDHB says testing has increased in recent days.
Between April 9 and April 12, 125 people were assessed with 75 (60 per cent) being swabbed.
After speaking with Director of Public Health at the Ministry of Health, Dr Caroline McElnay, WDHB chief executive Russell Simpson said it would be speaking with employers of essential workers and those considered high-risk to ensure those in their respective workforce that are symptomatic are referred to their closest CBAC for assessment as soon as possible".
He said he was confident with the testing strategy that had been undertaken at the six community-based assessment centres and that staff had closely followed the case definition guidelines.
Earlier in the week Whanganui's Medical Officer of Health, Dr Patrick O'Connor, said the low number of tests was "not a complete surprise" because there was a lack of community spread and a lack of connections to community clusters elsewhere in the country.
Of the 1000 people assessed at community-based assessment centres (CBACs) in the region up until April 10, 380 people were swabbed for Covid-19.
Nationwide, 61,167 people had been tested by April 11.
