Risk of coronavirus exposure increases greatly when indoors
Maui County saw 484 new confirmed cases of COVID-19 during the month of December. This is higher than all new reported cases, combined, from March through September. This alarming increase required decisive action to curtail a rapidly growing infection rate.
For this reason, the County of Maui recently limited social gatherings to five from 10, lowered the indoor capacity of bars and restaurants to 30 percent of maximum occupancy and instituted a 10 p.m. closure for these establishments. At the same time, we relaxed rules to enable bars and restaurants to expand outdoor service areas. After consulting with an industry representative, we agreed that these measures were preferable to closing restaurants down.
Some have asked why restrict bars and restaurants, but not retailers?
Maui County has received no report of community spread linked to any Maui retail location. Our large “box stores” have been limiting indoor capacity to 50 percent (or less) of maximum occupancy. Our smaller shops and stores also monitor and control the number of shoppers allowed inside at one time. In all cases, face coverings are required to be worn at all times.
A recent study by Clarkson University professors of engineering concluded the risks of COVID-19 infection multiplies when people are in close proximity, over longer periods of time, inside poorly ventilated spaces. As experts on fluid dynamics and aerosols, these professors use science to better understand how coronavirus particles circulate between people.
When individuals exhale, they release respiratory droplets. Some of the smallest droplets evaporate quickly, but some don’t. Those that don’t evaporate, known as aerosols, can remain suspended in the air for minutes to hours.
Most indoor spaces have poor ventilation that allows aerosolized droplets to concentrate over time to reach all areas of the room. That’s why infection risk goes up according to room size, number of people inside, and the quantity and quality of ventilation. The likelihood of infection for COVID-19 is highest when indoors, in close proximity to an infected person, over time.
Speaking loudly, yelling or singing generates larger concentrations of droplets, increasing the risk. That’s why most “superspreader events” involve crowded, indoor gatherings, such as noisy bars, business conferences, community events and large parties. Our medical advisers have linked several of Maui County’s recent infections to bars and bar-like behavior in social settings.
More importantly, people’s behavior in a store is quite different from that in a party, bar or restaurant. Shoppers typically pass one another quickly without much conversation. By contrast, bar patrons or party guests often spend long periods of time eating, drinking and socializing without the protection of masks while inside a crowded, poorly ventilated space.
These are the same factors that sparked the recent Harbor Lights COVID cluster that started with holiday choir practice. Singing or talking generates additional coronavirus aerosols that spread quickly in crowded living conditions. The Department of Health and Harbor Lights management are working together to isolate infections and mitigate any new spread to protect both residents and the wider community.
We all know what we should do to protect ourselves from the virus. Science has proven that mask-wearing, keeping your distance from others, frequent handwashing, not gathering in groups and moving activities outdoors is our best protection from COVID-19. Because the vaccine will require months to be administered, please continue doing these things to protect ourselves, our loved ones and our small businesses.
I would prefer not to restrict business activities because small businesses are the lifeblood of our economy. But the health and safety of Maui County residents remain my top priority. If the irresponsible behavior of a few continues to threaten the progress we’ve made, I won’t hesitate to enforce more restrictive protections. If you see someone who is not following our health guidelines, please remind them that the public and economic health of Maui County is everyone’s responsibility.
* Michael Victorino is the mayor of Maui County.