CHATHAM-KENT, ONT. -- Public health officials in Chatham-Kent are working to contain a major COVID-19 outbreak among migrant workers at a greenhouse facility.

The public health unit said that as of Monday evening there were 43 positive cases at Greenhill Produce in Chatham-Kent.

"No one should panic whatsoever," cautioned Medical Officer of Health Dr. David Colby. “Chatham-Kent’s numbers are among the lowest in the province, even taking this into account."

About 250 people work at Greenhill, and come from a number of countries including Guatemala, Jamaica and Mexico. They stay on-site in bunkhouses, and for that reason Colby said the virus is easier to contain.

"This is not a company that the public has access to, so we will be able to contain this in the situation where it is. None of the cases are severe enough to require admission to hospital. They can be isolated where they are."

The advocacy group Migrant Workers Alliance for Change is calling on the federal government to grant the Greenhill workers permanent residency status. 

"These workers are not able to assert their basic right for safe work," said spokesperson Syed Hussan. "You cannot speak out, you cannot complain because you’ll be deported. So they need permanent resident status now to be able to have health care, family unity and their right to protection the need. But Canada owes them."

Health officials said they may never know whether the virus was imported from another country, or if the spread began in within Chatham-Kent.

Colby said it will be difficult to trace, but the health unit is investigating.

"There were some recent arrivals, and there were some people who had been here for a year that had gone home on vacation then returned, but they did go through the quarantine process for two weeks just as federal law mandates from what we’ve been told."

Greenhill Produce did not take calls Monday, but issued a news release on Sunday saying containment of the virus and recovery of staff are top priority.