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Worse, it is less effective at higher concentrations.

Antibacterial and antiviral activity are lower if no water is present. Depending on microbe or virus, maximum effectivity were observed between 60-80%. Standard disinfection in lab is usually carried out with 70%.

The issue is that they started up late, most of the tests started up sometime around the second week of March. The response as a whole was not different from Italy. As such the outcome so far is more unexpected and could be a considered a lucky break rather than the outcome of some specific measures. The age distribution as well as the fact that in Italy there is more intergenerational contact has been speculated to play a role. However, the other issue is that it has circulated for quite a while untracked and that the testing is still way behind the actual rate. Depending on which metrics you use, Germany is about as old or a smidge older (depending on what age brackets you make).

Studies, including those in the link show an exponential decline within hours (with longer time on plastic surface). While you can recover active particles after a day or so, the number is greatly reduced (and will also depend on humidity temperature and other factors). You are also diluting the amount if you touch it and then touch your face, as each time there is less transfer. But as a whole it does not mean much more than wash your hands after touching stuff.

Death rate is a bad measure until towards the end. The most important measure is the increase and coverage of testing. Germany is not doing too well on either of them. The reason being that there are only mitigating measures in severe cases. I.e. once overwhelmed due to high infections, the system crumbles and deaths increases.

Germany is uncertain. They seemed to have a lucky start but were lagging in tracing and testing at the start. They have ramped up now and the next two weeks or so will provide more info. The current growth is still logarithmic.

Hope you dilute it down to 60-80 % first. There is an antibody based test (several actually) but not sure how well it works and whether they are put to test yet. So far all reinfections are suspected to be failure in tests. There is no strong evidence that folks get sick again (for now).

Phones can be cleaned with isopropanol, for example.

it really depends on your precise extraction protocols and specimens and I have seen quite a few different setups. If the concern is more about cleanliness, one would obviously opt for positive pressure. Though sometimes the specimen are biohazards or otherwise should not escape the room (e.g. if you work through soil samples you do not want it to get elsewhere) negative pressure would be better. At the same time, it should be noted that the room configuration is more about general concerns. Specific ones can further be addressed by installing clean benches or biosafety benches or zero-flow boxes as appropriate, for example. But generally speaking, when sensitive tests are run (such as for diagnostics) folks generally are more concerned about getting the test right (i.e. uncontaminated and clean) rather than worrying about stuff getting out. So if you run a lot of RNA samples or amplify from low abundance then most would opt for positive.

I think it is still the old nationalist thinking- things far away don't affect me. And if it starts I just close the borders and am safe. I am only worried if those close or similar to me are affected. Very human and thus very stupid.

I would exclude Japan from the list for now. They have a very low testing rate and it is unclear whether it is well contained or not. With regard to 5) a key element is that many (if not all) of these countries had a task force established in the wake of SARS. Those have become a central coordination centers for tracking, stockpiling of supplies and so on. What really annoys me is the fact is that while the epidemic raged in China, folks just looked on. It appears that folks still do not understand the concept of globalization. Just because their country dodged the bullet so far, does not make them immune. There were three months during which preparations could have been done, but apparently folks just started to realize it could hit them after Italy.

The measure is not protect yourself, that one is about minimizing droplet production. They recommend, for example the use of shawls or ski masks, which offer little when being sprayed on. The article specifically said that there is no scientific evidence that simple surgical masks are going to protect (though, as a sidenote, it would be very difficult to determine to begin with*). The virologist cited in the article specifically says: "Everyone thinks you protect yourself with the mask, but in truth you are protecting others. That thought specifically was used by the Chinese government to ask folks to cover their faces. Fundamentally, of course, minimizing exposure to your face can also reduce exposure, but it requires a number of behavioural changes that are often not conducted. Such as having a tight seal with your face, but not touch it while wearing. That is hard as after a while they tend to itch and especially if you are not busy with your hands, it is easy to touch and contaminate. *As a whole studies have shown some reduction when worn by sick people. For the reverse data is more scarce and there may be a potential weak effect, but only paired with other measures, such as hand washing (and the latter has shown a much stronger effect).

The trial is not "just" to satisfy regulations-they are to figure out whether they work in the first place. At this point we do not know if any of these work. It does not make sense to mass produce something if you do not know whether it at least elicits a significant immune response. And even then it is not clear whether that response will create immunity, but in an accelerated scheme hundreds to thousands would be tested within phase III (so it is not really waiting - it is data gathering). Again, this is the big thing, the a bit promising is about creating an immune response, and that will be ascertained primarily in Phase II and secondarily in Phase I with a relative handful of folks. The big problem is of course is if after committing to one particular vaccine if folks in PhaseIII still get sick- which could take a while to figure out, depending on exposure in a given test population. Therefore it is important to have several options in the pipeline.

Sounds like the 90 days fast track is for Phase I, similar to the other one. Rather obviously it will (not "potentially") take longer to test efficacy and there is a further timeline before first applications (which would be in the III).

Quarantine is generally applied to infected or potentially infected folks. If tested positive, it can be extended until certain indicators are met.

It is difficult to be certain. Incubation time is an estimate itself is skewed toward symptomatic cases. For example you take the time point of a known contact with an infectious person and look when the secondary infection results in symptoms. The issue of course is if the contact happened in asymptomatic cases the data becomes kind of invisible and in pre-symptomatic cases one need to backtrack the contact, which can be tricky. So essentially those cases can only be estimated. That being said, in the early phases of infection viral particle counts are still low, so there is unlikely a lot viral shedding going on. There have been a handful reports of asymptomatic transmission, so it is a possibility, but data is too scarce so far to be actually certain how likely it is. It does seem to be much rarer than symptomatic transmission, but at the same time, asymptomatic transmission are also somewhat easier missed. As a whole I think the data so far suggests that pre- or asymptomatic transmission is probably not a major driver, but there are a handful of studies (most not reviewed yet and based on secondary estimates) that suggest a bigger role. Unfortunately we do not have certainty either way yet, the disease is just too new.

Not necessarily (or at least only partially). For the most part it depends on parameters like spread and test capacities. Especially at the beginning tests are often limited to high risk patients. As such there are plenty of non (which are not considered in this estimate) or mildly symptomatic folks that are not tested. They may recover (or never know that they were sick) unless they were tested as part of contact tracing. But overall, chances are that actual transmissions are not well aligned with actual positive tests. This is where much of the Western world is right now. Age is also a consideration as more younger folks have only mild symptoms are are also often undersampled. The authors also took travel estimates into account. Looking at the Wuhan data, especially toward the later time points, the crude death rate dropped dramatically, and was more in line with fatality rates reported outside of Hubei, indicating that there are parameters, such as overwhelmed health care system that drove up fatalities. Accordingly, the authors found that the crude fatality rate outside Hubei was 0.85%, which is even lower than the estimated symptomatic case fatality risk as assessed by the authors for Wuhan. So in that regard there is a strong underestimation of transmission especially at the earlier stages of testing, and depending on how many tests you roll out relative to transmission, it can at some point approximate the actual value. The authors here tried to model the true transmission rates in order to figure out what the effective risk of dying after developing symptoms is.

I am just reading a new paper that tries to provide a better measure of COVID-19 associated symptomatic case fatality risk. The result was lower (1.4%) than crude case fatality calculations (4.5%).

I could find some data, but I am not sure what you ate interested in. So far there is no indication that certain age groups do not get sick. Rather the age distribution follows familial infection clusters. If a family with kids get sick, the kids will eventually be positive. They are more likely to only have mild symptoms and may be undersampled. So co-infection with influenza and sars-cov-2 has actually been reported. However one potential issue is that one test is based on isolating RNA and performing an RT-PCR. If you have a high Influenza titer they influence the detection of sars-cov-2 RNA (with the RT step usually being the limiting factor). Differential analysis can distinguish them but can be difficult for standard test labs.

That makes perfect sense, cheers.

I have not looked at the particular paper, but there have been quite a few over the last decade (especially on norovirus, I believe) that support antibacterial as well as antiviral effects. It is at least plausible that it also applies to coronaviruses (though probably more info is needed).

There are a few hypotheses and studies on the mechanisms, but no super obvious answers yet. Some studies suggest that radical development (as with many other metals) may be a feature, but the slow rate in the absence of active metabolism (and in dry systems) has made some question the likelihood for viral killing. One common observation is that the genetic material seems to degrade over time. Some suspect that released copper ions result in oxidizing reactions with proteins which ultimately also affect DNA stability and there are a couple of others around. But as a whole it has been pretty well established that contact killing by copper is a reproducible effect and that it is also typically dose-dependent. There are also studies showing viral reduction on steel, but the reduction is usually slower than on copper (with some bacteria results are similar).

If anything folks were unusually cooperative during this outbreak.

More to the OP: I was wondering what restrictions scientist would face with respect to copyright..? After all studies are published. The only concern is whether folks have to pay to read them, which is a whole different discussion (but quite a few journals seem to put COVID-19 related articles into open access).

But the good news is that with multiple directions to develop a vaccine we might have an better idea what works better.