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CV🦠News, Week of October 12, 2020

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Healthy greetings, friends and patients of TVD,

Love living in “the valley”. See image above, of a billboard courtesy of Santa Clara County. 😀

Silicon Valley is the land of the entrepreneur, which leads me to give another shout out to Steve Kirsch and his COVID-19 Early Treatment Fund (CETF), which is administered by Rockefeller Philanthropy Advisors, a 501(c)(3) organization created to ensure the rapid and successful completion of outpatient clinical trials of existing drugs that lead to effective early treatments for COVID-19. Last week the CETF announced the results of a recently funded outpatient clinical trial at Washington University in St. Louis that examined the viability of fluvoxamine in patients with mild COVID-19. The trial results indicated that fluvoxamine, if given early in the course of COVID-19, significantly reduced the likelihood of hospitalization.

As always, please give me a call if you have any questions or concerns.

(Eric Weiss, MD, September 28, 2020)

NOTE: CV🦠News is a labor of love. If you enjoy reading this, please share widely! Was this forwarded to you by a friend? Please subscribe here.

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After months of social distancing and with holidays approaching, many people are turning to quarantine bubbles, to try to balance the risks of the pandemic with the social and emotional needs of life. When done carefully, research shows that quarantine bubbles can effectively limit the risk while allowing much needed social interactions with family and friends.

Make no mistake, however, staying indoors, avoiding all contact with friends or family, and having food and groceries delivered would be the best way to limit your infectious risk, particularly if you are in a very high risk group. But overall health also includes mental as well as physical being.

However, the negative mental health impacts of the pandemic are becoming more evident. A recent survey found 13.6% of US adults endorsed symptoms of serious psychological distress, up from 3.9% in 2018. One quarter of young people 18-29 years old reported serious psychological distress, the highest levels of all age groups. Quarantine bubbles, therefore, are not just a convenient concept to allow us more social interaction. Isolation poses serious health risks — both physical and emotional — that “bubbles” can help alleviate while improving social well being and quality of life.

If you do decide to gather, do all you can to make sure it’s safe, and follow basic guidelines. Dr. Bonnie Maldonado, Professor of Pediatrics (Infectious Diseases) at Stanford Children’s Health has some advice, “This is a time when we all want to see our family and friends, and we can still do that, but I think we just have to be very cautious about how and when and how many.” She recommends only meeting in a “small group” where you know what other interactions people have had, and advises hand-washing and masking as much as possible. Outdoor gatherings are usually safer, but if you must meet indoors, make sure to open windows or doors for increased airflow and better ventilation.

HOW TO BUILD A QUARANTINE BUBBLE

First, everyone must agree to follow the rules and be honest and open about their actions.  Individual behavior can put the whole team at risk, and the foundation of a quarantine bubble is trust. Bubbles, which should be no more than 8 – 12 people, should discuss in advance what to do if someone breaks the rules or is exposed to an infected person. If someone starts to show symptoms, everyone should agree to self-isolate for 14 days.

Second, everyone must decide how much risk is acceptable and establish rules that reflect this decision. This is not a time for shyness or ambiguity, no assumptions should be made, no hesitations left unaddressed. Some teams feel okay to have friends visit, but only outside with everyone wearing masks. Other bubbles with higher risk members might not agree to that.

Finally, everybody has to actually follow the rules, comply with physical distancing outside of the quarantine bubble, and be forthcoming if they think they may have been exposed. The rules can change over time as we learn more about this virus, so communication should be ongoing and dynamic, so that everyone can completely understand and agree to any new rules.

THE RISKS OF JOINING A QUARANTINE BUBBLE

Any increase in social contact comes with more risk. Understand two important considerations in deciding how much risk you are willing to accept in joining a bubble:  

First is asymptomatic spread. Current data suggest that at any given time, up to 45% of infected people are asymptomatic or pre-symptomatic and able to transmit the virus to others. The best way to know is to get tested, and some teams might want to require testing before joining.

Second is that the consequences of getting sick are not the same for everyone. For people in higher risk groups, the risk must be seriously considered in relation to how strictly observant a quarantine bubble is, how many members it has, or whether to join at all. The consequences of a high risk person getting sick is much more serious.

One of the most unsettling aspects of this pandemic is uncertainty about this virus and what lies in the months ahead. But many things are known. If individuals are informed and sincere in their efforts and follow the regular guidance of social distancing, mask wearing, and enthusiastic hand-washing, quarantine bubbles can offer a robust and structured middle ground approach to manage risk while experiencing the joy and benefits of friends and family. 

Sky Pittson, MD, October 12, 2020

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California residents no longer have to limit their gatherings to only people in their households.

Anticipating an uptick in social events as the holiday season approaches, the state eased its guidelines for private gatherings during the coronavirus pandemic, now allowing people from up to three households to meet up for less than two hours.

But there are some rules. The gatherings must be held outside, hosts must collect contact information for contact tracing in case of an outbreak, and everyone is required to wear face coverings and maintain social distance. 

The new rules strongly discourage people from singing, chanting, shouting, or playing wind instruments, as those activities increase the release of potentially infected droplets.

People should not attend gatherings if they feel sick or are in a high-risk group, the state says.

Governor Newsom reminded people that easing of restrictions does not mean going back to normal gatherings. It is meant to provide some guidance.

City and county health policies may correspond with, or override, the state’s rules. So it is crucial to follow the updates from your local officials as the holidays approach. We all hope to be with loved ones during the upcoming Thanksgiving but given the recent uptick in national cases, we must exercise caution.

Prerana Sangani, MD, October 12, 2020

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Masks, depending on the material and fit, can filter out the majority of viral particles, but not all.  Aside from the public benefit of protecting others by wearing your face mask, many experts believe that universal masking reduces the “inoculum” or dose of the virus for the mask-wearer, leading to more mild or asymptomatic infection.

In a September perspective paper co-written by infectious disease and public health experts at UCSF and Johns Hopkins and published in The New England Journal of Medicine, the authors explain this theory dates back to at least 1938, when the “LD50” (virus dose at which 50% of exposed hosts die) was first explained. Controlled experiments in animals to calculate dose-mortality curves have been common over the years, but studies examining the dose of virus associated with different levels of disease severity in humans have been limited to non-lethal viruses. In one excellent example, healthy human volunteers were exposed to different doses of wild-type influenza A virus – those exposed to higher inocula of administered virus developed more severe symptoms. While such a study on SARS-CoV-2 would not pass ethics board committees, an animal model demonstrated hamsters were less likely to contract SARS-CoV-2 infection with a surgical mask partition, and that those hamsters that did contract COVID-19 with simulated masking had milder manifestations of infection.

There is strong evidence that rates of asymptomatic and mild infections have increased over time as universal masking has increased. A systematic review of studies on COVID-19 before universal masking found the rate of asymptomatic infection with SARS-CoV-2 to be 15%. More recent reviews and the CDC place this number now at 40–45%. Early estimates of the rate of asymptomatic infection due to SARS-CoV-2 on the Diamond Princess cruise ship (before widespread mask wearing) was 20%. A more recent cruise ship outbreak, in which all passengers and staff were provided masks after the initial case was detected, resulted in 128 of 217 passengers and staff eventually testing positive for SARS-CoV-2 by PCR, with 81% remaining asymptomatic. Accumulating research provides several similar examples, up to a 95% asymptomatic infection rate in an outbreak at a Tyson chicken plant in Arkansas in which 124 workers eventually tested positive, and where all workers wear masks all day. 

The authors review that while asymptomatic infection can be a problem in terms of increasing spread, it can also be beneficial at a population level in that higher rates of exposure to the virus without the unacceptable consequences of severe illness could lead to greater community-level immunity, which could actually slow spread as we await a vaccine. That said, it is important to remember that the level of effective immune response to various severities of illness in COVID-19 infection has yet to be determined. And, of course, this population-level opining is not a recommendation at the individual level to avoid other important social distancing measures in order to inoculate oneself through one’s mask – for each exposure, it would be impossible to know the viral inoculum getting through the mask and the impact that will have on the individual mask-wearer. It is safest to continue to practice careful social distancing and mask-wearing.  Perhaps the information above is simply extra motivation for consistent mask wearing.

Jennifer Abrams, MD,  October 13, 2020

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For the most part, coronavirus is still thought to be spread most commonly through droplet transmission, however there is growing evidence that airborne transmission can also occur in some circumstances. The CDC recently updated their guidance on “How COVID-19 Spreads” to reflect this, but they have not changed their general prevention recommendations given that it does not seem to routinely be the method of transmission.

By definition, airborne transmission is the spread of infection through exposure to tiny exhaled virus-containing respiratory droplets and particles that can remain suspended in the air over long distances (usually greater than 6 feet) and periods of time (minutes to hours). In contrast, droplet transmission usually occurs after someone is in close contact (within 6 feet) of an infectious person who exhales larger respiratory droplets. Typically these larger droplets fall out of the air due to gravity while smaller ones spread apart in the air and thus the concentration decreases with distance beyond 6 feet. 

Airborne transmission of coronavirus has always been a concern in certain healthcare settings, but published reports now also show that it has occurred in certain community settings. Each of these incidences has involved poorly ventilated and enclosed spaces where people were taking part in activities that led to heavier breathing and exhalation, such as when people are singing, shouting or exercising inside. In most of the known cases where airborne transmission occurred, the infectious individual was in the enclosed space for more than 30 minutes (in some cases, hours) and infections happened in those more than 6 feet away and also in some who passed though the space soon after the infectious person had left, confirming that the droplets were lingering in the air. Even so, airborne transmission is not deemed to be a source of efficient (routine or rapid) spread of coronavirus to people far away from an infectious person, but it is still best to avoid circumstances where airborne transmission is more likely to occur.

The CDC guidance currently states that “existing interventions to prevent the spread of SARS-CoV-2 appear sufficient to address transmission both through close contact and under the special circumstances favorable to potential airborne transmission.” In addition to the commonly recommended interventions (social distancing, use of masks in the community, hand hygiene, surface cleaning and disinfection), the CDC notes that appropriate ventilation and avoidance of crowded indoor spaces are especially relevant for enclosed spaces, where circumstances can increase the concentration of suspended small droplets and particles carrying infectious virus.”

Jackie Phillips, MD, October 13, 2020

 

HOPE AND GRACE

If you have made it this far, time for a reward, something to lighten your day, and acknowledge the human spirit. Find some escape, or perhaps even inspiration, in this ever growing collection of works and perspectives gathered from around the world. Please contact me directly if you have come across something that has lifted your heart today.  Dr. Eric Weiss

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Guerilla Art?

This week’s Hope and Grace lightness comes in visual form. There are some wonderful images to be seen in a public Facebook group here. Enjoy.

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Again, CV🦠News is a labor of love. If you enjoy reading this, please share widely! Was this forwarded to you by a friend? Please subscribe here.

*****

Yours, in health and resilience,

Eric and the TVD MD team…