Coronavirus - worldwide spread and control

https://www.theguardian.com/world/2...iving-in-uk-in-run-up-to-lockdown-quarantined

 

Covid-19: Confidentiality agreements allow antibody test manufacturers to withhold evaluation results
https://www.bmj.com/content/369/bmj.m1816

 

Isn't that akin to holding a cricket series that everyone must bet on, by law, and then refusing to release the results of matches?

In other words - not cricket.

 

He'll be one of the two who didn't give permission. Though I expect he still has direct alarm to the cops still. Possibly the other one is his wife. Just wild guesses!

 

I'd forgotten the whole thing about "cross reactivity"; the test isn't specific to a single virus, other similar virus's can give you a positive result. I'm a bit worried since my limited grasp of PCR assumed that the test was highly specific (but if you picked a common gene sequence then not so).

I'd need to sit in a darkened room for a while to think the numbers through!

Thanks to both of you @Snow Leopard @JaneL

 

Hi, I apologise for not replying sooner, I missed this post earlier. This study does provide suggestive quality evidence that asymptomatic transmission is possible and suggests the importance of larger scale studies to confirm.

There was a range of sampling times for the first survey:

8 new cases (out of 2,343 tests) doesn't give us much to go on statistically and basically assumes the test has 100% specificity and sensitivity.
The testing rates of 85.9% and 71.5% of the population were fairly high, but unfortunately this means the contact tracing is inherently incomplete and there could be additional sources, for example the parent/3 siblings could have been infected via another route. Note that "With symptoms" was "Defined as the presence of fever and/or cough." hence it is possible participants could have had cough or other symptoms but chose not to report them and aren't really "asymptomatic". The study also didn't explain how it dealt with participants who reported symptoms such as cough (but not fever), but tested negative, which could have been false negatives. Also note that participants may be somewhat tight lipped about any individuals who may have violated the lockdown, if they want to protect them from getting into trouble (social desirability bias).

3 cases were apparently contracted from "asymptomatic" individuals, 2 of which did not report any symptoms (note that 3/2343 = 0.1%)
1 "symptomatic" and 1 "asymptomatic" case had no known contacts.
1 "symptomatic" case had a known "symptomatic" contact
2 "asymptomatic" cases had contacts with "symptomatic" cases.

8 cases reported being asymptomatic across at both sampling times. Aside from never having symptoms, I guess they could have been lucky with a sub-15 day period of symptoms, or they chose not to report symptoms, but it's also possible they were false positives. (8/2343 = 0.3%)

From Table 3, only one participant with symptoms had seemingly only been in contact with 'asymptomatic' individuals - but had 4 known contacts from outside the house (perhaps there were more?). Then there is the possibility of these individuals being exposed to 'mild' false negative cases who did not have a fever.

All in all, the results are compelling, but limitations of sample size, completeness of contact tracing, symptom reporting biases, and unknown sensitivity/specificity of the overall testing procedures (there are risks of contamination etc.) mean that the results are not conclusive.

 

So why is journalism on scientific and health matters so desperately poor these days that this is now a revelation?

 

The primers are supposed to be quite specific to the virus, but the specificity of a PCR test is not just based on the primers/probes, but everything else that can accidentally go wrong.

https://pubs.rsna.org/doi/10.1148/radiol.2020201343

 

https://amp.svt.se/nyheter/inrikes/virologer-anvand-munskydd-i-offentliga-miljoer

DN Debatt. ”Använd munskydd i publika miljöer och i äldrevården
https://www.dn.se/debatt/anvand-munskydd-i-publika-miljoer-och-i-aldrevarden/

https://translate.googleusercontent...arden/&usg=ALkJrhgsr2z6KxCpjG2tF94w5vqe0UsNlQ

It's baffling to me that personnel in elderly care are discouraged from using protective equipment, as the Swedish Public Health Authorities has admitted to having failed in protecting the elderly and vulnerable.
"Better safe than sorry" surely should apply in a situation like this.

“In this situation, to discourage the general use of protective equipment in the elderly care system is incomprehensible, especially as the virus in the exhaled air goes down significantly if oral protection is used.
In such a contagious, such a serious and, among the elderly, often fatal illness such as covid-19, the precautionary principle must prevail, ”the article states."

 

Coronavirus: Top government scientist Neil Ferguson resigns from SAGE after breaking lockdown rules

 

https://amp.theguardian.com/world/2...-suffered-less-from-coronavirus-than-the-west

.

 

Could there be a confound there with reporting practices in Eastern Europe in relation to deaths connected to COVID? I know Eastern Europe isn't Ecuador, but nevertheless, it would be a much stronger argument if they were able to demonstrate the same advantage using data on excess deaths.

 

Looks like Donald is going to disband the virus task force. Time to move on and open the economy folks.

 

Thanks so much @Snow Leopard for your analysis of this paper, much appreciated.

I posted the following report which supports the public wearing of face masks in the thread about face masks:
https://rs-delve.github.io/reports/2020/05/04/face-masks-for-the-general-public.html.
The only reason I mention it here is because it rather helpfully collates all the evidence for asymptomatic/pre-symptomatic transmission of SARS-CoV-2. I’m not sure if there is anything in there that you haven’t already seen? (Unfortunately I don’t have the energy myself to look through all the studies and don’t worry if you don’t either!)

I think you’re right though that the two studies that I presented as evidence for asymptomatic transmission, whilst compelling, do not provide conclusive results. So I’m glad you picked me up on that.

 

On May 5, (yesterday), the U.K. had 4,406 new cases. The number of new cases is not going down significantly. (infact according to worldometers, the 7 day moving average was lower on April 28th).

Yet lockdown restrictions expected to be eased. https://www.theguardian.com/politic...rds-as-pm-expected-to-allow-more-time-outside

My partner who had to go out today, reports streets are already getting busier, with more people out and about. I also have been seeing more cars out on the roads outside my flats, for the past 1-2 weeks. I am very worried about a bigger resurgence.

 

"What’s Behind South Korea’s COVID-19 Exceptionalism?
Seven weeks ago, South Korea and the U.S. had the same number of virus deaths. Today, South Korea has fewer than 300, and the U.S. has more than 70,000."


https://amp.theatlantic.com/amp/article/611215/

 

The trend for new cases in UK is flat, definitely not going down significantly I would say.

All but 7 US states are also relaxing restrictions, and most of them have increasing cases and deaths.

Cuomo got it right again, new york is now helping the US look good because their numbers are dropping, take new york out of US data and the numbers are getting worse.

Some southern European countries are also expressing desire to open up their tourist economy.

I dread to imagine what the next few months has in store.

 

I think all the focus in a vaccine bring viable in a super short time period is also lulling people into a false sense of security.

I got a very funny look from relatives during Skype session when I simply stated that we don't know enough about the virus to know if a vaccine will work- other coronaviruses have no vaccines and it may be that treatments are developed ( like HIV) instead.

There is a muddling of preventative and curative.

There is an expectation that a vaccine will solve everything.

 

If testing in the UK has ramped up significantly, but the number of positive results has stayed pretty flat, that's a sign that the true number of new cases is probably falling.