As it is time to add some hikes to our calendar, I would like to offer some thoughts.
The pandemic has required us Muleteamers to adapt in various ways. Because many of us are not comfortable carpooling with people outside our households, hikes with long drives (for example 90 minutes or so to the Chiricahuas) are not as attractive as they once were. In addition, the fact that we arrive at a destination with a greater number of cars also tends to eliminate trailheads with limited parking.
For those reasons it may turn out to be necessary to repeat hikes this season more than we have in previous years.
I have also become increasingly aware that some Muleteamers are not comfortable on hikes with others who are not masked. From the beginning of the season, the only mask requirement that I personally have referenced has been the City of Bisbee policy, which applies at the Courthouse but not out on many of our trails. My own reasons for not communicating a need for masks on the trail included (1) I am aware that certain individuals may have difficulty with physical exertion while masked, and (2) since I am not a policy-maker for Muleteam, I hesitated to go beyond applicable government requirements.
I am however the one with my fingers on the keyboard. During the pandemic, approaches to safety have in many ways evolved. Last spring we were hiking distanced but not masked. This season we have had hikes where everyone is masked and others with a substantial number of unmasked hikers. Meanwhile, even since the beginning of our season in October, public health guidance has become clearer. Last month the director of the Arizona Department of Health Services said "Based on recently released data, we now know masks provide more protection than previously thought. . . . I encourage everyone to wear a mask whenever they are around people they don't live with." For that reason the State's guidance is always to wear a mask when out in public. The CDC says that those who are unable to wear a mask because of difficulty breathing during high intensity activities should be sure to keep at least 6 feet away from others.
In light of all this, it seems to me reasonable that Muleteam recommend that all those who hike with us wear masks on the trail, with an exception for those who have difficulty with physical exertion while masked. Those in the latter category should be asked to be scrupulous about staying six feet away from hikers outside their households.
I welcome comments here on the blog, or by email to ebernstein2001@yahoo.com.
In the meantime, we do need more hikes scheduled. I am grateful to all of those who have already led hikes this season. Our hikes may have to be more local than in the past, we may repeat hikes during the season, but it is still enormously valuable to get outside!
Keep on trekking,
Elizabeth
Thanks Elizabeth! I for one really appreciate your request for people to wear masks. Some are still not taking this virus seriously and the numbers continue to rise, even here in Bisbee. I hope to do more hikes with the group now.
ReplyDeleteThe following is from Stephen Sklarow:
ReplyDeleteBasically a 1 mph breeze is 1.46 feet per second. Walking at 2mph is ~3 feet/sec with no breeze. Our imaginary experiment has particles spreading in 360 degrees from their source which means concentrations fall off as the cube power. Ergo 3 feet away (exclusive of breezes) means that there are 1/27th as many particles available to infect. Six feet therefore is 1/216 as many.
Recent research, although not complete by any means, has indicated that the contraction of an infection requires a minimum number of virions to be inhaled deeply into the lungs (exclusive of many other factors many of which are still unknown). If one is breathing at a rate of 20 inhalations/minute then this can occur only 1/3 of the time. Further, it is suspected that the severity of an infection may be directly related to the dose of virions inhaled and that lesser virus loads may indeed be responsible for less severe infections.
The virions are transmitted from an infected person to another contained in droplets of some size. Larger droplets fall out of the air quickly. Smaller droplets can travel further, and are also more affected by ambient conditions (breezes).
Indeed, to my knowledge, no-one has measured the differences in viral load exhaled by asymptomatic vs symptomatic vs. "superspreader" individuals as well as the infectivity of the virions themselves (possibly there is a difference in the spike proteins ) from these different sources.
If one is shopping in an enclosed area such as Safeway there are no breezes to speak of. If you are walking behind someone who exhales (coughs-sneezes-shouts-clears their throat etc. etc.) the likelihood of inhaling air which was just exhaled by someone is far far higher than when outdoors.
Most masks function more efficiently if one were to breathe exclusively thru one’s mouth (both in and out). Breathing thru the nose results in some portion of the air bypassing the mask.
Although by this time, after almost a year of this issue, one might expect a whole lot more data on the proportion of people who contracted covid and had NEVER removed their mask. Not having this data is a failure on the part of the health department and medical researchers. The information collected by contact tracers should have provided some input on this important piece of information. By following the travels of someone who became infected it should be possible to make a very good guess as to where the infectious event occurred and all the circumstances surrounding it (and I do mean ALL).
Considering the above I suggest the following course of action:
If there are ,for example, 18 hikers, four of which are in a high risk category and/or are skeptical of the efficacy of masking I suggest that these individuals stay at the front of the group such that they are surrounded by masked individuals and are potentially less exposed. The remaining 14 people might therefore hike without a mask . . . maintaining sufficient distance from each other and from the aforementioned hikers in the front. In this way they will not be inconvenienced by having to wear a mask if they so choose not to.
Be advised I am not in any way denigrating the practice of mask wearing as a prophylactic measure and am furious when I see people ignoring this requirement under circumstances that warrant mask wearing.
I welcome any "devil’s advocate" comments as long as they are grounded in science rather than ignorance.
Stephen
Dr. Stephen Sklarow
Microbiologist/Virologist/Biochemist
https://pubmed.ncbi.nlm.nih.gov/4780740/
reference:
1.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7429109/