So here are a few thing I am wondering about (and might have missed in my reading).
This is the NEJM article on how one is supposed to investigate a new infectious disease. (aka epidemiology) Published Feb 18
emphasizes the need to check families and contacts to see if people with few symptoms are infectious. Meaning you need to do a lot of tests on low risk folks to figure out what is going on.
Starting these epidemiologic and surveillance activities promptly will enable us to choose the most efficient ways of controlling the epidemic and help us avoid interventions that may be unnecessarily costly or unduly restrictive of normal activity.even given that there is usually a two week lag in publishing "urgent" articles, one wonders why this wasn't done in China a lot earlier: say in late Dec or early January. True some of these investigations require the ability to test, but hey, you can also do clinical questionaires to give you a bit of an idea to figure out if maybe it is spread from person to person, so maybe you shouldn't let everyone go home for the New Years celebration.
ah, but where are the studies here? Slowly dripping out from the CDC, so we should know more as days go by.
which brings me to another question: What test is being used by whom?
and the acute test for the acute virus is a PCR test for the actual genetic material of the virus: this checks if you are infected and can spread the disease.
but this might not check if the person is immune or not: for that you need to check the anti body titer (IgM for early period, IGG for full immunity, positive after ten days).
the problem with antibody tests is that they won't pick up early infections, only turning positive after a few days, when the person hasn't had time to develop immunity. So in early infections, you can spread the disease with a negative antibody test.
the reports say this was the test used by China early in the epidemic.
Since these tests do detect if a person has had the infection, but this means the test will pick up those who have recovered and won't spread it.
the delay in diagnosis in antibody tests, which miss early infections, was why in the past, we docs in Oklahoma, where Rocky Mountain Spotted fever was common, just treated all fevers with tetracycline: Because the rash and the blood test for Rocky Mountain spotted fever didn't turn positive right away, and by then the disease could kill you.
... so I am never quite sure which test the lay press is talking about when they say test results.
and of course, another problem with all of these sophisticated tests is that they have to be accurate:
Instapundit notes:
CHINA SYNDROME: China Supplied Faulty Coronavirus Test Kits to Spain, Czech Republic.
if these highly publicized tests were faulty, can we trust the test data from China, where maybe their tests were similarly flawed?
This is one reason the US FDA was slow in approving a test, by the way: you need to get the test right or it's useless.
So stop your complaining about Trumpieboy (and implying that the hard working bureaucrats at the FDA were incompetent) for not having thousands of tests immediately as if someone had a magic wand and poof suddenly they appeared. The FDA/CDC were making sure that the damn things actually worked.
and now that the USA has tests that actually work, all and sundry are getting tested, so we see huge numbers of cases reported.
Not in the reports: Which test?
which is why I noted different tests measure different things: acute ongoing infections that can spread, or old infections of immune recovered folks just show who used to have it and now they can't spread the disease.
another question about those reports that USA has more reported cases than China... Is this because the USA is doing more tests and their tests are more accurate. Or maybe it's because China isn't doing a lot of tests anymore, or isn't reporting them...
And if you believe China's claim that they only have a few cases now, mostly in folks entering that country, well, as the saying goes, If you believe that I have a bridge in Brooklyn that I'd like to sell you.
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some of these questions are being answered by the meticulous investigations of the CDC, but you have to read the technical details at their website.
LINK discusses that Washington state nursing home.
LINK2 discusses severe cases.
what is the demographics of the US cases? Someone pointed out that younger cases in New Orleans and NYCity might have HIV (diagnosed or undiagnosed) from MSM or drug use.
If so, then the spread of Wuhanflu in the homeless, who are drug users and often have chronic health problems (hep C, TB malnutrition) could be terrible.
Are the cities forcing these people into hotel rooms?
Some wag suggested they should put them in Trump Tower,. Well, yes, hotels and even college dormatories could be forced to house such people, but those empty cruise ships could also be used for emergency housing or even emergency hospitals.
another question: Now, with Mexico closing the border to the USA, I am reading about fresh produce that is being destroyed due to the long lines (a problem here in Manila also).
Is the virus slowing down the importation of illicit drugs (e.g. opioids from China trafficked via the Mexican drug cartels)? A similar question could be asked here in the Philippines: some of our Shabu (aka meth) is made locally, but a lot of it is from Burma etc. via Chinese cartels, and of course Manila is a distribution center to distribute these drugs all over the world... but the airports are essentially closed right now....
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taboo question: Is there a racial difference in the severity of the disease? if so, which races?
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Some cases have relapse, according to early reports.
but will having a mild case give you immunity? This is important, since if it does, then herd immunity will stop the spread of the disease. (unless, like influenza, or the common cold, a new strain pops out so you could catch the new strain again.) And of course, it would mean a better hope that a vaccine would work.
So far, however, no one knows if having the disease will make you immune.
Early in March there were reports that there were two variations of the Wuhan flu: one mild and one lethal.
Have studies since then confirmed this? And if so, are the viruses similar so that there is cross immunity?
But unless the mild case brings you resistance to future infections, it suggests the 1918 Spanish flu redux, when the flu broke out in multiple places and was much more lethal in 1919...because of the cytokine storm.
this brings up all sorts of questions about vaccines: if you get partial immunity, immunity to a different strain of virus from being infected or from a vaccine, could this result in inducing a cytokine storm in a small percentage of people who come down with a slightly different strain of the virus...but alas I'm not an expert: but here in the Philippines we were harmed by the Dengue vaccine, which probably saved a lot of lives but killed some kids (partly because there are four variations of the germ and usually you get the severe disease in your second infection)..., so if they do get a covid vaccine, expect the anti vaxxers to come out in force.
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update: In the Philippines, up to recently anyone could pick up antibiotics without a prescription (now they are getting stricter about this). So now the authorities said: no chloroquin without a prescription.
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Lancet article on using Chloroquin for viral infections from 2003 and why it works. For later reading.
historically, the ancient Inca used it to treat "fevers" (maybe malaria or maybe not), and later many people often gave "jesuit bark" aka quinine for "fevers".
This broad anti viral activity might be why it worked when the fever didn't come from malaria.
and one reason that it works in early cases but not in severe cases might be because it stops replication of the virus: once you are sick it won't stop the cytokine storm.
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