Contact tracing, say public health officials, is key in stopping COVID-19 in its tracks. File photo

Contact tracing, say public health officials, is key in stopping COVID-19 in its tracks. File photo

Contact tracing is crucial, says north Island’s medical health officer

Dr. Charmaine Enns talks about the importance of case ID and follow-up

With all the discussions around the pandemic and responsive measures such as handwashing, masks and lockdowns, there is one strategy that could prove crucial to public health efforts.

In October, a doctor with the World Health Organization called contact tracing the “game-changer” needed for fighting the coronavirus in the near future.

It’s a sentiment echoed by the north Island’s medical health officer, Dr. Charmaine Enns. In an interview with the Record, she emphasized what contact tracing is, how it works and why it is so important in stopping the spread of COVID-19.

“This is the most important public health intervention we have,” she said. “We have only so many tools in our toolbox.”

Enns wants to see people live their lives, but do so in a manner that will protect them. To keep communities from having to go into lockdown, public health professionals and the public need to be vigilant in their efforts to trace the potential spread whenever a COVID-19 case crops up.

RELATED STORY: Pandemic response for parents starts with good info, says Enns

Case ID, then contact follow-up

The process is two-fold, starting with case identification, then contact follow-up. The aim is not to test everyone, only those with symptoms that could be COVID-19. When someone tests positive, public health staff respond quickly, with the positive lab result sent directly to the communicable disease (CD) nurses and the medical health officer in the area of the ‘case’ – in other words, the person who tests positive.

People are considered infectious for 10 days from the first day of their symptoms, though some symptoms can linger and repeat swab tests can remain positive for up to 100 days. However, the person is no longer infectious and not able to give COVID-19 to others else once they get to 10 days from the start of symptoms. (The exception concerns critically ill patients in hospital.)

The CD nurse interviews the case to determine when symptoms started, how they may have been exposed, their travel history and, importantly, any close contacts who may have been exposed to COVID-19 while the case is infectious. As a precaution, contact follow-up also includes any close contacts in the two days before the case showed symptoms in order to take into account potential transmission in the pre-symptomatic period.

Most close contacts don’t become cases

Time and space are key factors in defining a close contact. The general rule of thumb is that those who have been face to face without physical distancing for a cumulative 15 minutes or more is considered a close contact.

“Because this is COVID, a lot of people are keeping their social circles small,” Enns said. “This means the list of close contacts tends to also be small.”

If someone is considered a close contact, the person is supposed to self-isolate for a 14-day period from their last contact with the person who is positive. If anyone is going to develop COVID-19, it will occur within 14 days, known as the incubation period.

Public health staff follow up daily. Many people are choosing daily electronic follow-up but phone calls are also an option. If someone develops symptoms, they arrange for testing.

A negative test will not shorten a close contact’s 14-day self isolation period as the contact is still in the incubation period.

“The majority of close contacts do not go on to become cases,” Enns added.

On Vancouver Island, public health staff are testing about 1,000 people a day, and about “99.9 per cent” do not have COVID-19, meaning staff are testing too many people with symptoms not predictive of the disease.

The most important elements here are identifying the actual cases, followed by the close contacts who might have been exposed and ensuring they are isolated for the necessary time.

“This stops transmission,” Enns said. “It stops it in its tracks.”

If societies can do this, according to Enns, it can help avoid measures such as lockdowns.

Close versus casual contact

Another thing to consider is the difference between a casual and a close contact.

“If you are not named by public health as a close contact, it should not keep you from doing the things you should be doing,” Enns said.

Many people now are worried about being a contact of a contact, and needlessly staying home from work or keeping their kids out of school. Enns emphasizes someone is only considered a close contact through exposure to a person who not only shows symptoms but tests positive for COVID-19.

If the rising number of cases in B.C. is alarming, the relatively low incidence on the Island is more encouraging. Vancouver Island has kept case numbers low and has, for months, been able to have people isolate themselves, and if sick, recover at home rather than in hospital.

Definitions matter

Another challenge is terminology. All too often, Enns said, there is confusion in the media between “isolation” for those who become sick and test positive versus “quarantine” for close contacts of cases. If it seems like some game of semantics, it is because public health professionals want to be careful about asking people to stay home for 14 days because it is not an easy thing to do.

“Words matters, definitions matter,” Enns said, adding the term ‘self-isolation’ has evolved to cover both those in quarantine and isolation.

Role of businesses

There are other tools that can help with tracing contacts. Many businesses, especially ones such as restaurants or bars where customers might stay for an extended period, are following WorkSafe BC and using logbooks to get customer contact information. This can be helpful, Enns said, when regular channels to find out a case’s contacts are incomplete – in other words, when exposure comes through community transmission but they cannot pinpoint how a person contracted the disease.

“They have made our jobs so much easier for contact follow-up,” she said.

When the public gets a report about potential exposure at a particular business or on a flight, for example, this is how a notice is generated, but it’s not the first of line of defence. That remains with the public health working with those who test positive and their close contacts.

“Contact tracing let’s us have containment,” she said. “This is within our control.”

Evolution of knowledge

Enns also said shaming behaviour on social media toward people with the coronavirus or the insisting we hear about ‘every case in every place’ will only make it harder to get the right people to go for testing.

“We don’t need to police each other as citizens,” she said.

In the months since the pandemic was declared, the understanding of preventative measures, treatment and other factors has changed. Enns is concerned by the amount of misinformation circulating, and she reminds the public that the learning process for everyone, including people working in public health, is ongoing and the knowledge is evolving constantly.

“We’re in a pandemic where we know things are going to change,” she said. “We don’t have a playbook.”



mike.chouinard@comoxvalleyrecord.com

Like us on Facebook and follow us on Twitter.

Coronavirus

Just Posted

Winter breakfasts at the Willows Tea Room traditionally fund projects and programs for the Kiwanis Pavilion through the Oak Bay Kiwanis Pavilion Foundation. (Black Press Media file photo)
Family comes through for Oak Bay Kiwanis dementia care home

Residents at Victoria care home get new bus, programs

A search is underway for a 75-year-old fisherman who went missing near Port Angeles Thursday evening. (Courtesy of U.S. Coast Guard)
Search continues for angler missing between Port Angeles and Victoria

Canadian, U.S. Coast Guard searching for 75-year-old man reported missing Thursday evening

Stanley Fischer, right, died while in a Victoria police jail cell hours after he was arrested on Nov. 15, 1981. (Photo courtesy of Mark Fischer)
Victoria police not reopening investigation into man’s 1981 death while in custody

Stanley Fischer’s death was ruled a suicide after he was found in his jail cell

A multi-building residential development on Erskine Lane in View Royal was approved by council on June 15. (Courtesy Town of View Royal)
Dire shortage of three-bedroom apartments, says View Royal mayor

New development to feature wide range of rental units, amenities for tenants

A vial of AstraZeneca vaccine is seen at a mass COVID-19 vaccination clinic in Calgary, Alta., Thursday, April 22, 2021. The website for a Broadway theatre showing "Springsteen on Broadway" said it would only allow guests "fully vaccinated with an FDA-approved vaccine" — Pfizer-BioNTech, Moderna or Johnson & Johnson. THE CANADIAN PRESS/Jeff McIntosh
No Springsteen for you: AstraZeneca not good enough to qualify for Broadway ticket

View Royal mayor among those unable to attend New York entertainment due to COVID-19 restriction

A small pod of Pacific white-sided dolphins pass by close to shore in Campbell River June 16, 2021. Still capture from video courtesy of Kimberly Hart
VIDEO: Dolphin sunset captured from Vancouver Island shore

Spectacular setting for view of travelling pod of Pacific white-sided dolphins

(Black Press Media file photo)
POLL: When was the last time you visited the mainland?

The films are again lighting the screens at local theatres, the wine… Continue reading

Anyone with information on any of these individuals is asked to call 1-800-222-TIPS (8477) or visit the website victoriacrimestoppers.ca for more information.
Greater Victoria Crime Stoppers wanted list for the week of June 15

Greater Victoria Crime Stoppers is seeking the public’s help in locating the… Continue reading

Bella Bella is on B.C.’s Central Coast, accessible only by air and ocean. (Tom Fletcher/Black Press)
B.C. provides $22 million for Heiltsuk development on Central Coast

Elders care home project, tourism, lumber mill supported

The federal government says it wants to ban most flavoured vaping products in a bid to reduce their appeal to youth. THE CANADIAN PRESS/AP-Craig Mitchelldyer
Health Canada proposes ban on most vaping flavours it says appeal to youth

If implemented, the regulations would restrict all e-cigarette flavours except tobacco, mint and menthol

Seth Rogan’s vibrant orange sculpture was sold for $7,000 above Vancouver Art Gallery’s initial estimation at auction Tuesday. June 15. (Heffel Fine Arts)
Vase made by Seth Rogen sells for $12,000 at Vancouver auction

The B.C.-born comedian has a new pot habit and it’s paying off

BC Lions running back John White IV (3) runs with the ball during first quarter CFL football action against the Ottawa Redblacks in Ottawa on Saturday, September 21, 2019. THE CANADIAN PRESS/ Patrick Doyle
BC Lions file trademark for new logo

Canadian Football League team files for new design on June 1

The remains of the Mid-Island Co-op in Whiskey Creek along the Alberni Highway on Friday, June 18, after a blaze the day before devastated the gas station. (Michael Briones photo)
VIDEO: Camper van explosion burns Vancouver Island gas station to the ground

Nine fire departments responded to the incident, no injuries reported

The Montreal Police logo is seen in Montreal on Wednesday, July 8, 2020. Some Quebec politicians are calling for an investigation after a video was released that appears to show a Montreal police officer with his leg on a young Black man’s neck during an arrest. THE CANADIAN PRESS/Paul Chiasson
Probe called for after video appearing to show Montreal officer’s knee on Black youth’s neck

Politicians call for investigation after clip evokes memories of George Floyd incident

Most Read