A new presumptive case of COVID-19 in Newfoundland and Labrador has been found in the Eastern Health region, the province's chief medical officer of health said Friday.

Dr. Janice Fitzgerald said the person is at home and self-isolating, and did so "very quickly upon returning, but not immediately."

The new case follows three now-confirmed cases in the Labrador-Grenfell Health region.

At Friday's daily update, Premier Dwight Ball said to further clamp down on the spread of COVID-19 anyone who has travelled outside the province — whether within Canada or internationally — will be required to quarantine for 14 days.

"If this situation wasn't serious we would not be doing this," said Ball.

Watch the full Mar. 20 update:

Ball said the province will be doing everything in its power to implement the strictest screening measures possible, including health assessment forms to be completed at points of entry across Newfoundland and Labrador.

Haggie said the province's points of entry will be "significantly reduced" over the course of the weekend as Air Canada cuts down on its flights into Gander and Deer Lake.

"At the moment, Marine Atlantic and the air operators are screening people at the point of boarding. So if their mechanisms are as robust as we hope then symptomatic people will simply not get on the planes or on the ferries," he said.

"Ours will then be a second line of defence. We're looking at a health self-assessment questionnaire at the point of entry where folk would get the same questions that they have on the online survey at the moment and then sign a declaration that they have filled that out honestly and leave that at the airport or ferry terminal before setting off to go straight home."

When asked specifically about travelling across the Labrador-Quebec border, for example, along the Labrador Straits where the ferry for Labrador leaves from Quebec, Ball said they will work with the communities to figure it out, but he did not provide any concrete guidelines for how exactly that would be done.

There have been 791 people tested in Newfoundland and Labrador as of Friday, with 300 people in self-isolation being monitored by public health officials, said Fitzgerald.

Testing centres in progress

Newfoundlanders and Labradorians will soon be able to get tested at designated sites, but Health Minister John Haggie stresses it will be by appointment only.

Haggie said the province will start using assessment centres for testing, and each region will have several. Locations will be worked out in the coming days.

The three regional health authorities within Newfoundland will be looking at using a drive-thru system to minimize person-to-person contact, while Labrador-Grenfell Health may opt to do things a little differently based on geography, Haggie said.

"Western and Eastern are probably going to start up in the next 24 hours and Central by Monday," Haggie said.

According to Eastern Health, a testing centre will be set up at St. Teresa's Elementary School on Mundy Pond Road as a drive-thru location.

The Gathering Place will also be set up for the vulnerable population in the downtown area of St. John's.

Both locations will be by appointment only.

A location for mass testing is still in discussion, according to Eastern Health, but the Jack Byrne arena in Torbay is a possibility.

The new case was travelling came back from Spain <a href="https://twitter.com/hashtag/covid19nfld?src=hash&ref_src=twsrc%5Etfw">#covid19nfld</a> —@PeterCBC

Mobile screening sites in western Newfoundland will be open 8:30 a.m. Saturday. Western Health said the sites will allow for more efficient screening, once the need arises.

"We are anticipating that in the coming weeks the need for testing will increase and we're certainly trying to be prepared so we can do more testing once that arrives," said Regional Director of Community Health, Darla King.

The testing should only take 10-15 minutes.

King said a parking lot attendant will verify the appointment and the patients will enter the parking lot to wait their turn. Once ready the vehicle will then pass through the drive-thru where a nurse will take a sample with a nasal swab and then it will be shipped to St. John's.

King said Western Health should be able to do 40 tests a day.

CBC News has asked Western Health for an interview about a testing centre being built in the Corner Brook Civic Centre's parking lot. (Troy Turner/CBC)

Given the public nature of the sites, Western Health is asking that passers-by are compassionate to those using the site.

"We would ask that people respect their privacy and not be sort of up and watching and looking to see who might be going for testing and those sorts of things," King said.

In circumstances where patients are unable to get to the mobile screening sites due to health reasons, home visits will still take place.

Regional health authorities want to ensure there will be no rush of people clamouring to get tested.

"This will make more efficient use of personnel," Haggie said. "If public health [officials] advise you you need a test, you can take your vehicle by appointment to one of the nearby test centres."

Everybody who wants to be tested has to be screened by public health officials. The first step is calling 811 and giving them your information. Someone from the health authorities will follow up and determine if you need testing.

So far, just under 700 people have been tested in the province. Four tests have come back positive.

A health-care worker speaks to a test patient at a COVID-19 assessment centre at Brewer Park Arena in Ottawa, during a media tour on March 13. (The Canadian Press)

"As far as I'm concerned, if you get a presumptive positive on our local tests at the moment, clinical decisions will be made based on that."

A province has to send 50 negative and 50 positive cases to Winnipeg in order for the national lab to verify the local tests are working. Newfoundland and Labrador doesn't have to send its negatives away for confirmation anymore, since it crossed the threshold of 50 several days ago.

Since the province hasn't seen anything close to 50 positives, those tests must still be confirmed, even though the health minister said he has confidence in the local testing.

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