Laumann was surprised by the early results of the mass testing. But he said that final results are expected on Sunday and by then it may possible to get a bigger picture of the outbreak.
This will help authorities determine how long the lockdown – slated to end June 30 – should last, Laumann added.
Residents in Gütersloh and Warendorf flocked to testing sites this week, some waiting up to 3 hours to be tested. The government of NRW has made testing in both communities free of charge at test stations or through individuals' family doctor.
In the state of Lower Saxony, whose border with NRW is close to the affected communities, some 45 employees of a meat plant tested positive for COVID-19. The company Wiesenhof said the results were part of a screening of some 1115 employees that was triggered after 23 workers were found to have the disease.
Many residents of the two communities rushed to get tested in hopes that a negative result will allow them to be exempt from some of the restrictions that other federal states have begun imposing.
The popular summer holiday destination of Mecklenburg-Western Pomerania, along with Schleswig-Holstein, Lower Saxony, Baden-Württemberg and Bavaria, have all imposed travel accomodation restrictions for people from Gütersloh and Warendorf who are unable to show a negative coronavirus test.
Rhineland-Palatinate has also imposed a quarantine obligation for travelers from risk areas abroad or at home, which would include the two communities.
Neighboring Lowe Saxony said Thursday that holiday guests from Gütersloh and Warendorf will have to leave the state, unless they arrived before June 11 or are able to show a negative COVID-19 test.
The moves has triggered a conversation among German states about how to regulate travel of movement in the event of single-area outbreaks, with Saarland Premier Tobias Hans saying he would be in favor of a nationwide ban on travel for residents in districts with high infection figures.
City under lockdown: Henning Schulz, Mayor of Gütersloh, speaks to DW