Tag: Erin Bromage

Liked What’s the deal with Masks? (erinbromage.com)

Face mask use is a social contract. My mask protects you; your mask protects me. But face masks are not perfect and they need to be used in conjunction with other measures to lower risk of infection such as physical distancing and hand washing. There is ample evidence to suggest that widespread use of masks results in significant reductions in the transmission of respiratory viruses. Mask use is grounded in biology and can have a real world and meaningful effect on slowing the spread of infection, protecting your coworkers, and those vulnerable members in your community.

Bookmarked The Risks – Know Them – Avoid Them (Erin Bromage PhD:)

In order to get infected you need to get exposed to an infectious dose of the virus; based on infectious dose studies with other coronaviruses, it appears that only small doses may be needed for infection to take hold. Some experts estimate that as few as 1000 SARS-CoV2 infectious viral particles are all that will be needed (ref 1, ref 2). Please note, this still needs to be determined experimentally, but we can use that number to demonstrate how infection can occur. Infection could occur, through 1000 infectious viral particles you receive in one breath or from one eye-rub, or 100 viral particles inhaled with each breath over 10 breaths, or 10 viral particles with 100 breaths. Each of these situations can lead to an infection.

Erin Bromage provides some perspective on why some places are riskier than others and how to avoid them. She explains that to be infected you need to be exposed to an infectious dose of the virus. The amount of dose is dependent on the delivery, whether this be a cough, a sneeze, a breath or speaking.

To make sense of this, Bromage reflects on a numbers of scenarios, including a restaurant, workplace, choir and birthday parties.

When assessing the risk of infection (via respiration) at the grocery store or mall, you need to consider the volume of the air space (very large), the number of people (restricted), how long people are spending in the store (workers – all day; customers – an hour). Taken together, for a person shopping: the low density, high air volume of the store, along with the restricted time you spend in the store, means that the opportunity to receive an infectious dose is low. But, for the store worker, the extended time they spend in the store provides a greater opportunity to receive the infectious dose and therefore the job becomes more risky.

This has me thinking about my own work and when we might return to open planned office space. Although we do not hot desk, it would seem that time and space are key ingredients to spread. No matter what strategies are put in place (one person in the lift, hand sanitiser units, limit to the size of meetings) it would seem that spread is somewhat inevitable given the right conditions?

Replied to Time to rethink the face mask! (Erin Bromage PhD:)

If you are wearing a mask, and an infected person breaths, coughs, or sneezes on you. Can you take the mask off without contaminating yourself or your environment? Here’s the fun part. Make your mask. Wear your mask. Then get one of your kids to cover the entire mask in shaving cream. Can you get the mask off and into a safe space without getting shaving cream on anything? Practice this!

Erin, I so often struggle to make sense of infection. I really like your use of shaving cream to explain how you might be infected while removing a mask.