TORONTO (AP) — Canada is increasing a payroll subsidy to small- and medium-sized businesses to now cover up to 75 percent of salaries as the country braced for a shutdown that a top health official said will last months.

Canada's Deputy Chief Public Health Officer, Dr. Howard Njoo, said they are in it for the long haul.

“It's not going to be days and weeks, it's going to be months,” Njoo said. "Is there a possibility of a second wave? Who knows."

Prime Minister Justin Trudeau announced a major increase over his original 10 percent wage subsidy plan. Trudeau said it became clear they needed to do much more.

“We have to get through these coming months of restricted economic activity when people need to stay home,” Trudeau said Friday.

The prime minister said it means people will continue to be paid even though their employer has had to slow down or stop its operations because of COVID-19.

He said he hopes employers who are being pushed to lay off workers will think again. And he hopes those who have already let people go will reconsider given the new wage subsidy. It is backdated to March 15.

“We're going to be here for you,” Trudeau said. “Small- and medium-sized businesses are the backbone of our economy. You are collectively the largest employer in the country. You support millions of families."

Benjamin Bergen, executive director of the Council of Canadian Innovators, said the government is finally hearing the concerns from the business front lines with the wage subsidies. He said many companies may go bankrupt in April.

"It is really, really bad and many won’t make it regardless of these announcements. Even a 100% wage subsidy would be too little to help given the long list of other costs, particularly rent," said Dan Kelly, president of the Canadian Federation of Independent Business. “We’ve had five business owners call us this week talking about suicide.”

Canada's central bank also cut interest rates for the third time this month.

Ontario, Canada's most populous province, meanwhile, will send out emergency alerts to cellphones, radios and TVs on Friday, warning recent travelers to stay at home. The alert will tell travelers returning to Ontario that they are required by law to self-isolate for 14 days as they are at high risk of spreading COVID-19 It will tell them, ``DO NOT visit stores, family or friends.''

The message will say that everyone should stay home to help stop the spread of the virus.

Trudeau, meanwhile, said it would be a mistake for the Trump administration to position troops near the Canadian border. He said he's told that to the White House, and that he's still seeking clarity on American plans. The Wall Street Journal, citing an unidentified U.S. official, reported late Thursday that the Trump administration had dropped its consideration of the plan. Canada and the U.S. already closed the border to all non-essential travel.

Canada has more than 4,043 confirmed cases and about 39 deaths. Officials said about 6.5% are in hospital and 2.5% are in critical condition. Canada has conducted more than 165,000 tests.