6

People don't just act in response to official orders. People react to the perception of danger, and by the time various official responses were announced, they were already taking measures to prevent the spread of COVID-19 (some more effective than others). For example, look at the mobility data for New York: By the time the lockdown started on March 22, ...


4

The virus has actually continued to spread during the lockdowns, just at a slower pace than if no lockdown had been imposed. See for example Washington state in the USA. The hope is that the lockdowns have reduced the spread of infections to linear or sub-linear rather than exponential growth. Linear or sub-linear growth provides an opportunity for other ...


3

The closest thing I have found to this is a tool called the COVID-19 Airborne Transmission Estimator. It is basically a spreadsheet on which you can tweak various parameters and get an estimate of the number of people infected at a given gathering. It was developed last summer by a professor at the University of Colorado; he is not a doctor but is a ...


3

The higher transmissibility of this VUI-202012/01 strain (if it is confirmed) is almost certainly due to mutations in the spike gene of the virus; see preliminary report from COG UK; another version of that with slightly more analysis confirms that one of the (17) mutations involved had been previously confirmed as causing higher transmissibility in a mouse ...


3

My interpretation of this advice is that it is creating a necessary loophole for, say, someone's physician to state that a patient should not wear a mask. Maybe it would include people on supplemental oxygen or with respiratory difficulties. Could also include people with injuries on the face. The point is that it is vague on purpose; it doesn't intend to ...


3

I would tend to think of coronavirus stability from a biophysics point of view. The virus is a small droplet of water inside a lipid membrane, with some proteins in the membrane and a bunch of proteins+RNA packed inside. It is very sensitive to Kampf 2020 (a) detergents - these dissolve the membrane and presumably cause the contents to spill out, (b) RNA ...


2

To partly answer my own question, after trying quite a few different potential keywords for these shields, I did find one 2014 paper Efficacy of face shields against cough aerosol droplets from a cough simulator Health care workers are exposed to potentially infectious airborne particles while providing routine care to coughing patients. However, much is ...


2

Outbreaks and pseudo-outbreaks related to contaminated germicides have most commonly been reported with contaminated antiseptics. Outbreaks from contaminated high-level disinfectants have rarely, if ever, been reported. Outbreaks from contaminated intermediate- and low-level disinfectants have occasionally been reported. All outbreaks associated with ...


2

Well, since you already have a well-written answer, I just wanted to add this as another possible cause: Research done by the National Institute of Child Health and Human Development (NICHD) in 2008 found that the influenza virus has a butter-like coating. The coating melts when it enters the respiratory tract. In the winter, the coating becomes a hardened ...


2

Summary: #1 seems possible with Covid given the preliminary data reported from one of the Covid vaccine trials, which reported lower efficacy on asymptomatic transmission. It's also been observed with flu vaccines, although the picture there is a lot more complicated by a longer history of, multiple vaccinations/infections, faster strain evolution (compared ...


1

After being educated on the issue by a virologist (Georges Natsoulis), I understand the question needs answers at two completely different levels. First, our very own human genome has been in good part developed in conjunction with the input of left over viruses. Thus, without the input from viruses we would not be who we are. Second, viruses within our ...


1

The transmission onset of an individual is the time when the individual first contaminated someone else, as defined in the paper you mentioned, section Procedures, first paragraph, P_j definition:


1

Yes, there are. This study for France says there is a 1.5% chance of a second wave. This article discusses three different papers modelling successive waves of covid (not only two). As usual, conclusions depend on modelling assumptions and different scenarios. For instance, this article states the outcome depends on how R and other factors (whether the virus ...


1

The CDC advice is pretty clear as to staying inside your own group Do: Stay 6 feet away from others (“social distancing”) and take other steps to prevent COVID-19 If a park, beach, or recreational facility is open for public use, visiting is okay as long as you practice social distancing and everyday steps such as washing hands often and covering coughs and ...


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