Friday, March 27, 2020

The "Six Feet Away" Rule is Woefully Inadequate

“...the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease” (Bourouiba, 2020).

Dr. Lydia Bourouiba has published an important paper that updates 1930s-era models of respiratory infectious disease transmission based on the size of droplets emitted when a person breathes or talks or coughs or sneezes. Large droplets were thought to contaminate the area immediately surrounding an infected individual, because they settle before evaporating. In contrast, small droplets evaporate quickly and form residual particulates, or aerosols. However, the classification of droplet size (and therefore the mode of transmission) is not based on modern science. Yet this scheme still informs public health policy to this day.

The figure above shows a Multiphase Turbulent Gas Cloud From a Human Sneeze (Bourouiba, 2020). The puff trapped droplets of many sizes and carried them quite a long distance (23-26 feet!) while evading evaporation. Droplets that settle can contaminate surfaces. Aerosols may persist in the air for hours, depending on ambient temperature and humidity, as well as prevailing winds or airflow of indoor ventilation systems.1

Watch the educational video showing Respiratory Pathogen Emission Dynamics and you will be truly horrified!!

This newer understanding of respiratory emission dynamics has implications for mask and respiratory design, social distancing recommendations, and other public health interventions during and after the COVID-19 pandemic.”


Speaking of masks, droplets are visible after sneezing into a surgical mask (Granville-Chapman & Dunn, 2007). Although the paper was a light-hearted study appearing in the Christmas issue of BMJ, the spread of respiratory droplets is no longer a joke.




Footnote

1 A recent report by investigators in Singapore suggested the possibility of significant environmental contamination (including air vents) in the hospital rooms of SARS-CoV-2 patients (Sean Wei Xiang Ong et al., 2020). The air samples themselves were negative, however. And standard cleaning  procedures effectively decontaminated surfaces.


ADDENDUM (March 28, 2020): @SamWangPhD rightfully pointed out that sneezing is not a symptom of coronavirus-19 infection. My initial reply was that an asymptomatic individual could be strolling through a park and sneeze due to allergies. On a more scientific note, it's true that the COVID-19 symptom of coughing isn't as violent as sneezing. However:

"droplets of diameter 30 µm can have a horizontal range of up 2.5 m away from the cougher due to cloud dynamics."






References

Bourouiba L (2020). Turbulent Gas Clouds and Respiratory Pathogen Emissions: Potential Implications for Reducing Transmission of COVID-19. JAMA March 26.

Granville-Chapman J, Dunn RL. (2007). Excuse me! BMJ 335:1293.

Ong SW, Tan YK, Chia PY, Lee TH, Ng OT, Wong MS, Marimuthu K. (2020). Air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a symptomatic patient. JAMA March 4.


Thanks to @midendian and @perrymetzger for alerting me to this article.

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Sunday, March 15, 2020

Coping with COVID-19: Resources for Managing Mental Health



  • Don't shake hands. 
  • Maintain a distance of 6 feet. 
  • Don't touch surfaces that could contain respiratory droplets. 
  • Don't touch your face. [It's very hard to not touch your face.]

When your leaders fail to follow the most basic guidelines for preventing the spread of COVID-19, trust and confidence are eroded.





The coronavirus pandemic has raised (nearly) everyone's level of anxiety and stress. Rampant panic buying, superstore shelves emptied of toilet paper, selfish people hoarding hand sanitizer. Worries about elderly relatives, jobs, money, health care costs.

If you already have a serious anxiety disorder, how can you possibly cope in the current climate of fear and uncertainty? What if one of the core recommendations to help prevent disease transmission is the very pathology you've worked so hard to overcome?


Obsessive-Compulsive Disorder

Contamination fears cause many individuals with OCD to compulsively wash their hands. Meanwhile, the directive to frequently wash your hands with soap & water for 20 seconds could be quite triggering for some. The International OCD Foundation has provided helpful resources:

Resources for the OCD and related disorders community during the COVID-19 outbreak
In times like these, what the experts are recommending temporarily becomes our new normal. This may mean that you need to make some changes to your treatment, including which exposures you do, when you do them, how frequently, etc. What might normally be considered a “baseline” for people with OCD to aspire to should shift to match the recommended guidelines for as long as those guidelines are in place. A good suggestion would be to talk about the guidelines with your treatment team at your next session and go over how, if at all, your plan might change for the near future.

It is important for all of us in the OCD and related disorders community to remember that this is temporary, and understand that it may feel uncomfortable. You are not going backwards in your recovery journey because the baseline changes. These troubled times will end, and you will keep doing your best in the meantime.
They also provide recommendations for what you should and should NOT do.

Examples of What to do:
  • set a time limit of 5 minutes per day for reading news and updates from trusted sources
  • take breaks and allow yourself to do things you enjoy
  • consult your treatment team
Examples of What NOT to do:
  • avoid the temptation to learn “everything” about COVID-19
  • do not excessively wash your hands
  • don’t let “social distancing” rob you of your support networks seek online connections

Generalized Anxiety Disorder

Tips from Health Canada:

What to do if you’re anxious or worried about coronavirus (COVID-19)
  • Be self-compassionate
  • Limit the news & unplug from social media
  • Stop talking about coronavirus
  • Protect yourself
...and more


Health Anxiety
The constant new barrage of developments regarding the current outbreak of COVID-19 can cause particular challenges for people living with anxiety, stress and/or anxiety-based depression especially those that have health anxiety and/or OCD.
Suggestions from Anxiety UK:

Health and other forms of anxiety and coronavirus
  • Firstly, try to limit your exposure to news sources which are covering the coronavirus issue as this only serves to feed fear.
[an ongoing theme]


COVID-19 and anxiety – part 2
  • For those that have anxiety disorders such as claustrophobia, agoraphobia and panic disorder, some of the potential management strategies that are being discussed in relation to COVID-19 might give rise to specific challenges and thoughts of ‘feeling trapped’.
  • Fearing being ‘out of control’ and ‘being unable to tolerate uncertainty’ are actually common characteristics of many anxiety disorders and therefore it stands to reason why so many individuals with pre-existing anxiety may now be seemingly experiencing an exacerbation of their anxiety as a result of COVID-19.
[see Intolerance of uncertainty, appraisals, coping, and anxiety: The case of the 2009 H1N1 pandemic]


Post-Traumatic Stress Disorder

Suggestions from the National Center for PTSD:

Managing Stress Associated with the COVID-19 Virus Outbreak
  • Increase Sense of Safety 
  • Stay Connected
  • Cultivate Ways to be More Calm
  • Improve Your Sense of Control and Ability to Endure
Those who have been faced with life-threatening situations recommended the following strategies:
  • Quickly recognize, acknowledge, and accept the reality of the situation.
  • Make a plan for dealing with feelings of being overwhelmed or overly distressed.
  • Combat unhelpful emotions by using distraction or staying busy—both mentally and physically.
  • Avoid impulsive behavior.
  • Increase positive coping behaviors that have worked in the past.
  • Shift negative self-statements to statements that allow you to function with less distress.
...and more


Managing Healthcare Workers' Stress Associated with the COVID-19 Virus Outbreak
A strong service-orientation, a lack of time, difficulties in acknowledging or recognizing their own needs, stigma, and fear of being removed from their duties during a crisis may prevent staff from requesting support if they are experiencing stress reactions. Given this, employers should be proactive in encouraging supportive care in an atmosphere free of stigma, coercion, and fear of negative consequences.
[...this link has guidelines for a crucial segment of the population Heath Care Workers  — who may neglect their own self-care.]


Of Interest to Mental Health Professionals

Mental Health Concerns Arise Amid COVID-19 Epidemic
Experts studying the spread of novel coronavirus disease (COVID-19) are increasingly concerned about the psychological ramifications of the epidemic, particularly for older adults and medical staff working on the ground. The issue has been raised in several correspondence pieces published in Lancet Psychiatry.

Coronavirus on the inpatient unit: A new challenge for psychiatry

by Dr. Dinah Miller (contributor to the iconic and now-retired Shrink Rap blog)
. . .

COVID-19 represents a new challenge for the inpatient psychiatry unit. Some patients on an acute psychiatric unit may be agitated, uncooperative, or even violent, and it’s not hard to imagine the distress of anyone who has a patient spit on them as we’re all trying to remember not to shake hands. Inevitably, there will be patients who present for psychiatric admission with no respiratory symptoms, who are admitted and then become ill and are diagnosed with COVID-19. In the meantime, the potential is there for contagion to other patients on the unit, the hospital staff, and visitors to the unit.

Readers if you have any suggestions for helpful resources or personal coping strategies, feel free to comment here or on Twitter.

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