The commenter, Zekness, is a Canadian with a lot of knowledge of Medicine and Public health. We are posting his comments because of the risks that are not currently talked about. We might also make the comment that we have heard that the current test need to have a certain viral load in the body in order for the test to work. The current guidelines seem to indicate that the test need to be give 7-days after the onset of symptoms in order not to reflect a false negative. We added the bolding for emphasis. Thank you, Sundance and Zekness.
"zekness says:
the current PCR test is very sensitive to SARS, MERS and COVID-19…it was designed to be sensitive to all three, but only those….and it makes sense that this test was re-tooled in this way (which helps to explain why the US did NOT follow the WHO guidance in developing the field test….it did at first, but then realized…no…the test will need to be re-tooled for a much higher sensitive geared primarily for the COVID-19 virus, but ALSO for SARS and MERS…(because we want to know as early as possible in the field that any of these three may be in the wild…)
in the lab, where these tests are sent for confirmation/falsification examinations….is where the contagion is actually identified….
Dr. Fauci is talking “around” this aspect but the science and method is on solid footing.
The lab will establish exactly what genomic profile is at play..and it will confirm the field PCR test result…or not.
for the front line, the immediate actions are to take the PCR test result of positive-positive and start quarantine and begin contact tracing..and further testing…they do not wait for the lab results….but one has to realize, currently this model is based totally on people reporting feeling ill.
the reality is this model does not work effectively against a virus that has a long incubation period, mild symptoms or none at all realize a situation where many people are just not going to report illness…and become super-spreaders. and the days during incubation where no symptoms exist, they are shedding and transmitting.
then you compound this problem with the reality that testing is not feasible for “not sick” surveillance….random sampling yes….but that is like dragging a net in an ocean, catching 4 fish and assuming that will somehow give you a good idea about how many fish are in the ocean….it is a very problematic and bad way to steer pandemic control measures, or to count fish!
then you have the problem that PCR tests are very sensitive (accurate) but calibrated to only these three c-virus and only the current known strains….we know this SARS-Cov-19 will eventually mutate….it probably already has beyond the L and S known strains…will the PCR test be sensitive in it current formula to register precision sensitivity…? we have to assume it will not, based on former experiences….but if we are not taking “not ill” random sample AT SCALE…we will never know until it far too late to get those PCR tests re-tooled..
any way you cut it…we are always going to be looking back in time….and those delays will result in an always late reactionary effort…this will not express the goal of limiting the and trajectory of this pandemic.
the ONLY way to satisfy a goal of limiting this pandemic is to begin a very far reaching set of restrictions right now….travel bans domestically….shut down all non-essential travel and transmission routes….and hope and pray that citizens start taking action to self isolate and do all of the things they can to limit social contact.
possible? probably not…sigh..
just stating how this pandemic can be controlled in a far more effective way.
the downside…yes, the economy and people get distressed..
the upside…far fewer people are dead