Ministry of Contagion
Proceedings of the Temporary Provisional Ministry of Contagion
(work in progress ...)
- Bad news: elevated risk of COVID-19 contagion in and around 2169 Mission
- Good news: hazards might possibly be mitigated via engineering and education
- Unscheduled visitors not wearing masks and/or not maintaining distance
- Stairway air
- High-touch surfaces
- Air inside NB
- Grocery store on 1st floor (and similar elsewhere in neighborhood)
- No room for distancing
- People without masks.
- For people emerging from long shelter-in-place isolation:
- Be aware of urge to engage in conversation
- Be aware of influence via apparently normalized complacency
- Possibly less active immune system (?)
- Raise awareness: Visiting 2169 Mission is a risky activity. (Pepper yourself!)
- Initiate scheduled volunteers
- Agreed-upon protocols
- Buddy system
- Limit frequency of visits, consider post-visit quarantine
- Contact tracing / scheduled followup
- Agreed-upon protocols
- Disallow unscheduled visitors
- Avoid extended conversation when explaining
- Refer them to written info (such as this wiki page, etc - a printout or card would be nice)
- Be pleasant but do not risk the health of self and others to accommodate
- Any rare exceptions should be discussed first with buddy and others in the space
- Contact tracing / scheduled follow-up
- One person (or buddy pair?) at a time
- Avoid conversation on the way up the stairs
- High-touch surfaces:
- Indicate in all possible ways (ie, visual, tactile, audible)
- Light switches
- Etc etc etc ...
- Disinfect all touchable surfaces when arriving as well as before leaving
- and/or wear gloves (?)
- Air inside NB:
- Limit amount of time breathing in the space
- Schedule "free-breathing" breaks
- Anticipate unmasking
- ADA accommodation (?)
- Designated area by window if (non-buddy) others in space
- Buddy pairs (or "social bubbles" ?) maybe could be maskless by mutual consent (?)
- recent SF order stipulates okay for "same household" working in area not accessible to public
- also may be okay if sufficiently distanced
- Ventilate thoroughly before leaving
- Technology: vents / air filters / (ionizers? UV?)
- Maintaining distance:
- Technology: proximity alarm ... ("SIX FEET, ASSHOLE!")
- Grocery store etc: be aware of risk, avoid unless properly (N95 etc) masked.
- Bring lunch etc
- NB could (should) provide supplies, snacks, beverages, coffee etc
Regarding transmission routes and space closure
Available scientific studies regarding the stability of SARS-CoV-2 (aka. HCoV-19 or coronavirus) particles in aerosols (from breathing, coughing, speaking, etc.) and on environmental surfaces (from contaminated hands or aerosols settling) provide evidence that the viral particles remain viable for widely differing periods depending on the surface, ranging from several hours (for aerosols) to multiple days (up to 7 days on smooth surfaces).
According to one study, "SARS-CoV-2 was stable on plastic, stainless steel, glass, ceramics, wood, latex gloves, and surgical mask, and remained viable for seven days on these seven surfaces. As is shown in Figure 1A, the virus titer declined slowly on these seven surfaces. For example, its TCID50/ml [50% infectious tissue culture dose per millimeter] decreased from 105.83 at time zero to 10^2.06 at day 7 on plastic, which was about a 3.8 log10 reduction from the original inoculum." (1)
Another study on the stability of SARS-CoV-2 in aerosols and on various surfaces found that "HCoV-19 was most stable on plastic and stainless steel and viable virus could be detected up to 72 hours post application (Figure 1B), though by then the virus titer was greatly reduced (polypropylene from 10^3.7 to 10^0.6 TCID50/mL after 72 hours, stainless steel from 10^3.7 to 10^0.6 104 TCID50/mL after 48 hours, mean across three replicates)."
The same study also found that "HCoV-19 remained viable in aerosols throughout the duration of our experiment (180 minutes) with a reduction in infectious titer 3 hours post-aerosolization from 10^3.5 to 10^2.7 CID50/L (mean across three replicates). This reduction in viable virus titer is relatively similar to the reduction observed in aerosols containing SARS-CoV-1, from 10^4.3 to 10^3.5 TCID50/mL (mean across three replicates) (Figure 1A)." (2)
The CDC states that:
"The virus is thought to spread mainly from person-to-person.
- Between people who are in close contact with one another (within about 6 feet).
- Through respiratory droplets produced when an infected person coughs, sneezes, or talks.
- These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.
- COVID-19 may be spread by people who are not showing symptoms."
And further that:
"The virus may be spread in other ways. It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes. This is not thought to be the main way the virus spreads, but we are still learning more about how this virus spreads." (3)
Based on this information, "decontamination by time" would require the space to be kept entirely closed for an absolute minimum of 72 hours, with at a week being optimal to eliminate the risk of surface transmission. Taking this precaution as part of the effort to prepare the space for moving would be strongly recommended.
(1) Stability of SARS-CoV-2 on environmental surfaces and in human excreta. 2020. Yongjian Liu, Tianyi Li, Yongqiang Deng, Siyang Liu, Dong Zhang, Hanping Li, Xiaolin Wang, Lei Jia, Jingwan Han, Zhuchun Bei, Yusen Zhou, Lin Li, Jingyun Li. doi: https://doi.org/10.1101/2020.05.07.20094805 [pre-print article, not yet peer-reviewed]
(2) Aerosol and surface stability of HCoV-19 (SARS-CoV-2) compared to SARS-CoV-1. 2020. Neeltje van Doremalen, Trenton Bushmaker, Dylan Morris, Myndi Holbrook, Amandine Gamble, Brandi Williamson, Azaibi Tamin, Jennifer Harcourt, Natalie Thornburg, Susan Gerber, Jamie Lloyd-Smith, Emmie de Wit, Vincent Munster. doi: https://doi.org/10.1101/2020.03.09.20033217 [pre-print article, now published in The New England Journal of Medicine doi: 10.1056/NEJMc2004973]
(3) www.https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-covid-spreads.html [accessed 2020-06-26 at 10:16 PDT]