Public Health Restrictions

COVID-19 Questions & Myths

4. Why is this virus so hard to control - why do we need public health restrictions?

There are a few big issues. Unlike influenza, or SARS in 2004, the virus reaches high levels in the nose, throat and airways early in infection, and can be spread before people realize they may be getting sick (British Medical Journal).  People with COVID-19 can spread infection on average from two days before symptoms through 10 days after and some get few or no symptoms, It spreads quickly to contacts causing a relatively large number of people severely ill.

As a lot of spread happens in the first five days of even mild symptoms, so isolating yourself right away and getting tested for COVID-19 is very important.

Reference:
i. Virology, transmission, and pathogenesis of SARS-CoV-2, British Medical Journal

5. Is what we have right now a complete lockdown? What is a circuit breaker strategy?

In a complete lockdown, everyone is restricted to their homes, may not have visitors, and has limited time to accomplish essential activities outside the home (e.g., people might be allowed to leave their home for an hour a day to get groceries or fill prescriptions).  A lockdown may also involve measures such as mandated masking and provision of hand sanitizers at entrances and exits.  Partial lockdowns may restrict some activities by the type of activity, groups size allowed, and time allowed for certain activities.

A circuit-breaker is a time-limited partial or complete lockdown intended to drop transmission quickly. For example, a four-week circuit-breaker might be used to decrease cases enough to re-establish contact tracing and reduce stress on health care.  It is called a circuit breaker because it is similar to an electrical circuit breaker, which protects sensitive electrical equipment from damage by shutting down when it senses a potentially destructive surge of electricity. Similarly, a COVID-19 circuit breaker detects an increase in COVID-19 that could overwhelm the health care system, including contact tracing, and shuts down activities that allow transmission of the virus and could create a surge of cases.

6. What is the difference between a targeted strategy and a partial or complete lockdown strategy to control the spread of this virus? What is a circuit breaker strategy?

A targeted strategy restricts specific activities identified as high risk based on what is happening in that community (e.g.: dining in restaurants, drinking in bars, and/or attending church are closed or restricted). This strategy depends on robust contact tracing to identify where and how the virus is spreading. If the contact tracing shows that the restrictions are not working or that other activities are responsible for transmitting the virus, then the restrictions are expanded or modified. 

A lockdown focusses on restricting the movements of people outside their homes and visitors to their homes to minimize the number of contacts they have with other people or contaminated surfaces. In a complete lockdown, everyone is restricted to their homes, may not have visitors, and may only leave their homes for limited times to accomplish essential activities (e.g.: people might be allowed to leave their home for an hour a day to get groceries or fill prescriptions).  A lockdown may also enforce strict regulations on how people are to protect themselves and others when they are outside their home. (e.g.: people must wear a mask on public transport and any inside spaces must provide hand sanitizers at entrances and exits). 

A partial lockdown may combine restricting some movements in a less severe way such as only restricting the hours people are allowed outside their house, relaxing restrictions on the number of visitors allowed indoors or outdoors, and changing what non-essential activities are permitted.

A circuit breaker is a time-limited partial or complete lockdown to rapidly decrease transmission of the virus. For example, it could be imposed for four weeks with the goal of lowering spread of the virus enough that contact tracing can be effective and stress is reduced on health care services. If that goal is reached, then restrictions can be lifted. It is called a circuit breaker because both are ways to protect against a surge in many positive cases. An electrical circuit breaker protects sensitive electrical equipment from damage or destruction by shutting down when it senses a potentially destructive surge of electricity. Similarly, a COVID-19 circuit breaker detects an increase in COVID-19 that could overwhelm the health care system, including contact tracing, and shuts down activities that cause transmission of the virus.

7. Have the restrictions in Alberta made a difference?

Yes. The measures taken in spring of 2020 reduced the number of cases by the middle of June, with low rates until October. The set of restrictions which began December 12, 2020 are showing signs of "bending the curve" in all five zones as of January 14, 2020.

The most important measure of the success Alberta has had is the total number of deaths due to COVID per 100,000 population. By that measure, as of January 14, 2021 the New York Times “Canada Coronavirus Map and Case Count” map shows Quebec has 108 deaths/100,000, Manitoba has 59, Ontario 38, Alberta 34 and BC 22. 

Alberta's total number of deaths/100,000 is 20%-25% that of hard-hit countries such as Italy, US, UK, Mexico, Brazil, Spain and Sweden (Our World in Data). It is significantly worse than Australia, South Korea, Japan and New Zealand. 

References:
i. How is Alberta doing and what should we be doing next?, Centre for Health Informatics, Cumming School of Medicine, University of Calgary
ii. Canada Coronavirus Map and Case Count, the New York Times
iii. Cumulative Confirmed COVID-19 Deaths per Million People, University of Oxford