Corona-zona

  The other day, I was feeling a little sniffley, so I decided to crack open one of the at-home COVID-19 test kits the government has sent me over the last couple of years. There was a time there where they'd periodically send you four kits (two tests each) per household if you requested it.  I have received two tranches of these. When I tore into the envelope for the first one, I saw that all the tests had expired about 18 months ago. I opened the second envelope and its four tests had expired about a year ago. When I got my booster last fall, the pharmacist asked if I wanted some at-home tests. Not knowing the ones I had were expired, I said "no I have plenty." However, she insisted I take them, just in case.  Good thing I did, because I had to resort to one of those for my sniffles incident (test was negative). I note that the other tests in that batch will expire at the end of next month. What is going on? I checked and the FDA says the tests have a shelf-life of abou...

A few days ago, the CDC released new "streamlined" COVID-19 guidance  "to help the public better protect themselves and understand their risk." According to the author of the new guidance, it "acknowledges that the pandemic is not over, but also helps us move to a point where COVID-19 no longer severely disrupts our daily lives."  The new guidelines deemphasize prevention of transmission and emphasize prevention of severe disease. Greta Massetti, a C.D.C. epidemiologist, said at a news briefing on Thursday: We know that Covid-19 is here to stay. High levels of population immunity due to vaccination and previous infection, and the many tools that we have available to protect people from severe illness and death, have put us in a different place. What's in the new guidelines?  Here's an abbreviated list: Be up to date on vaccinations Do the same thing if your exposed whether you're vaccinated or not, namely wear a good mask for 10 days and get te...

  Image by  mohamed Hassan  from  Pixabay Everybody has now come around to the idea that COVID-19 is mainly caused by airborne virus particles . So instead of reaming our sinuses or making us spit in a tube, why can't they detect it directly in breath? Now they can. The FDA recently approved a breathalyzer for SARS-CoV-2. It uses  gas chromatography gas mass-spectrometry (GC-MS) to separate and identify chemical mixtures and rapidly detect five Volatile Organic Compounds (VOCs) associated with SARS-CoV-2 infection in exhaled breath. The results are available in three minutes. The test seems to be pretty accurate too. According to the FDA release, it correctly detects 91.2% of cases where people are known to be infected (via normal PCR tests). Better yet, it correctly identifies 99.3% of cases where people are known to be negative for infection.  Unfortunately the units are a little bigger than the alcohol breathalyzers the cope use. They are more like...

  As noted in an earlier post , one of the risks of contracting SARS-CoV-2 is that it may turn into a chronic disease referred to in medical terms as "post-acute sequelae of COVID-19" (PASC). It is known colloquially as long-haul or just long COVID. The CDC says the condition can last anywhere from weeks to years.  They give a long list of possible symptoms, but note that some of them can be "hard to explain and manage:" Clinical evaluations and results of routine blood tests, chest x-rays, and electrocardiograms may be normal. The symptoms are similar to those reported by people with ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome) and other poorly understood chronic illnesses that may occur after other infections.  Unlike other aspects of the disease where the oldest fare the worst, long COVID is more likely to affect younger people, according to a data  from people with private health insurance.  Nearly a third of victims are 35 or younger, and th...

  Unless you have no friends, you probably know a lot of people who are vaxxed and boosted and nonetheless are getting infected. If the vaccines work, how can this be? A recent article on the CBS News site asks and answers this question. In a nutshell, current variants have evolved to evade the antibodies generated by vaccines (and previous infections). And those tend to wane after a few months anyway.  That means you can get infected even if you're vaxxed and boosted. But the vaccines are still doing their job of priming your immune system to prevent a serious illness if you are infected. Vaxxed people feel protected from the virus so they let their guards down. They return to risky behavior like eating in crowded restaurants, not wearing masks in public, and so on.   Combine this with a more infectious variant and it's a recipe for a lot of mild infections in vaxxed people. I know a lot of people who have gotten infected recently. To a person they describe it as...

Yesterday's New York Times had a  story about people circumventing U.S. restrictions on testing for people traveling home from abroad. They are exploiting a loophole in the laws that requires tests for people entering the country by air but not by land.  So people who go abroad and test positive change their flights to arrive in Canada or Mexico then drive across the border. Because they have, y'know, shit to do ! One woman at least gave some consideration to her state of health and whether she might be infectious, but ultimately said she didn't follow the rules because she thought they were dumb: I had zero symptoms, no fever, nothing. I felt fine and when you’re stateside, the C.D.C. says you can end isolation five days after testing positive, so the same rules should apply when I’m traveling. It makes no sense that I can go to a wedding five days after a positive test in Miami, but if I catch the virus when I’m on vacation I can’t fly home. That should be illegal. She ...

  There is a new variant spreading that people are calling "stealth" Omicron. It is a variant of of the existing Omicron variant. According to the Washington Post  the variant has been detected in many countries, and this includes India, Britain, and Denmark. Three U.S. cases have been detected at a hospital in Houston. The virus is similar to Omicron, labeled BA.1 by researchers, but contains some mutations that make it different. The reason is it called "stealth" is that,  according to the UK Health Services Agency: Omicron BA.2 lacks the genetic deletion on the spike protein which produces S-gene target failure (SGTF) in some polymerase chain reaction (PCR) tests, which has been used as a proxy for Omicron cases previously.    This is also known as an "s-gene dropout" and you have seen it referred to in this blog before. Variants that have this feature can be quickly identified in the course of processing PCR tests. If a variant does not have the fea...

  I already mentioned this issue when I  blogged about testing a few weeks ago. But it bears repeating and emphasizing now the the Biden administration is distributing free antigen test kits to everybody. Starting yesterday, a day ahead of schedule, the Post Office began taking orders for the test kits. You can get four per address, which to be honest doesn't sound like enough for bigger households. Something to know about these tests is that although they are fast, they are not very accurate compared to PCR tests, which take days to process. So says a review of studies (sometimes called a meta-analysis) published not quite a year ago. They compiled the results of different studies done on different brands of rapid tests, which compared antigen test results to PCR test results on samples taken from the same people at the same time. Here is part of their "plain language" summary: In people with confirmed COVID‐19, antigen tests correctly identified COVID‐19 infection in...

  Two updates on testing. Antigen Tests Less Sensitive to Omicron On Wednesday I blogged about the challenges the new Omicron variant is posing for testing. Essentially, you can have antigen tests that are fast and inaccurate or PCR tests that are slow and accurate.  Antigen tests are just barely satisfactory for symptomatic cases (false negatives in 1 of 4 to 1 of 8 tests), and they are basically useless for asymptomatic cases (false negatives in 1 of 2 to 1 of 3 tests). Even that assumes the tests work for Omicron. Well yesterday the FDA announced that antigen tests are less sensitive to Omicron than other variants. They don't have information on how much less sensitive they are but are working to get that info. They are also trying to learn why and think the tests can be adjusted to compensate once they know. Dr. Fauci is quoted in this article: "What the FDA is saying today is that when you look at Omicron and its ability to detect Omicron, some of the tests have a dimin...

  Yesterday my sinuses felt somewhat irritated, my nose was running a little, and I had a little pang that could have been the beginning of a headache. I am fully vaxxed and boosted, so I wondered: Could I have a breakthrough case of the Omicon variant? There is growing evidence that Omicron produces less severe disease. Some people are claiming that it has different symptoms than "classic" COVID-19 too, ones more like a common cold.  Experts warn  that it's too soon to tell if the symptoms are fundamentally different from those associated with Delta. But this doesn't stop people like me from wondering whether any respiratory symptom might be COVID-19. At least four people I know—someone I work with, a friend, and two toddlers of another friend—have  symptoms of mild respiratory illness. They are all worried that they could have COVID-19 and have gotten or are seeking tests. There are many other people in the same boat. Public health practitioners are saying that th...

  On Sunday I noted that Arizona had not yet seen an explosion of cases due to the Omicron, like elsewhere. On Monday I thought there may have been detonation, with AzDHS reporting over 7000 new cases.  But today they're reporting just 1,976 new cases. So it looks like once again we have unreliability due to  delays in reporting cases . Anyway, ASU reported over 70% of tests with s-gene dropouts (explainer here ) yesterday. That means Omicron is definitely taking over in Arizona. So what should you do about testing if you think you're infected? The current choices are antigen tests and PCR tests. Antigen Tests Antigen tests are the kind you can buy (if you're lucky) at the drug store and that you can administer yourself. The tests produce results in 15-30 minutes. That's great if you're trying to catch an Omicron infection because it spreads quickly and you want to stay away from other people if you have it. The problem is that these tests are not very accurate. ...

  As noted in yesterday's weekly numbers update , I have been puzzled about why the positive test percentage in Arizona has been consistently trending down when new cases have been consistently  trending up. After all, it takes a test to identify a case, so it seems like the positive test percentage should go up as the new case rate goes up. The ASU Biodesign Dashboard has data on raw numbers of positive a negative tests.  So I downloaded that data and had a look.   One thing to note is that the number of tests has gone way up over the last month.  On August 6 the seven-day total was about 66K tests.  By August 28 the seven-day total was about 97K tests—almost a 50% increase. Of course, more testing don't explain the mystery downtrend by itself. But things become clearer when we look at the trends in positive vs. negative tests (dotted lines are trendlines): As we can see, both positive and negative tests are trending upward, but negative tests are t...

  A friend recently sent me a link to an article about how kids in the UK are faking COVID-19 tests to get out of school .  The tests in question are "lateral flow tests" that check whether anything in the sample binds to antibodies embedded in the test strips.   To take the test, you get a sample from your nose, then dissolve it in a buffer solution. You then pour that into the plastic test rig, and if a "test" line shows up the match a "control" line on the test strip, you're positive. This guy goes into details of how the tests work. It's kind of interesting, and you can read it if you're into things like that. But the scam has to do with that buffer solution. Not only does it dilute the mucus sample into something that can flow through the test rig, it also ensures that it is at a neutral pH level (acid-base) required for the antibodies to work and detect viruses. What the kids do is replace the buffer with some acidic substance like juice...

Last week I had a post about so-called "breakthrough" cases, i.e. people who get COVID-19 despite being fully vaccinated. The post noted that Arizona has a rate more than twice the national average. I asked an epidemiologist I know, who until recently worked at the Department of Health and Human Services, why that might be.  Here are the three answers I got.   Reopening and Mixing "One possibility is that reopening has increased mixing among the population and our case numbers are rising again, meaning more exposures than in places with lower case rates." This is true to some extent in Arizona.   As reported in my most recent by the numbers post, a small increase in infection rates started in Arizona about a month ago. Probably not coincidentally, this was shortly after the governor issued a reopening order .   But the rise wasn't that big, increasing only about 2 cases per 100K over the period. Also Arizona is in the lowest tier of states for infect...

  In a development that should surprise absolutely no one, a black market is flourishing for fake vaccination certificates and tests results, and probably fake vaccines.  Cyber-security firm Check Point has released an analysis showing a booming business in all three, with "Dark Web" advertisements up 300% in the past three months. According to their report: Fake COVID-19 negative tests can be had from various sellers for about $25 Fake vaccination certificates can be bought for $250 Various vaccines can be purchased for $500-$1000 per dose. Fake Records The tests and certificates are so easy to fake I'm surprised anyone would spend money to buy them.  My test results come to me as an email.  It would be child's play to change the name on mine to someone else's.  There is an "id number" and "order number" that could reveal the name had been tampered with. But the average consumer of test results (say, an airline) would have no way to check up ...

Here are updates on some recent Corona-zona posts. Anal Swabs After being scooped by Corona-zona on Chinese anal swab tests for SARS-CoV-2, Stephen Colbert did a bit on them during his monologue last Thursday (that part starts around minute 6:00). He makes some very funny jokes (if you enjoy scatological humor, which I do).  But in an additional tidbit, he reported that that U.S. officials in China told the State Department that they had been so tested.  The Chinese are denying it, naturally. But, come on, don't you think the U.S. officials would know if they had been anally probed by some Chinese dude?  DeSantis Has No Plan and Is Proud of It In mid-February I had a post about Governor Ron "Florida Man" DeSantis whining that he didn't get enough credit for his state's recent pandemic performance. I showed that Florida only looks good if you cherry-pick recent numbers, and that overall its performance has been terrible. Last week Salon.com ran  story  pointin...

  As noted in an earlier post , right now it's the wild west out there when it comes to masks. It seems they are hyped based on everything except how well they work filtering virus-size particles.   Now, the  American Society for Testing and Materials (ASTM) has come to the rescue with a new set of standards for "barrier face coverings," known to most of us commoners as masks. If you follow that link you will be required—for reasons unclear to me—to go through a registration process that includes providing your address and phone number and verifying your email before you can see the standards.  I registered and got the document so you don't have to. There are basically three important parts to the standard, requirements for design, testing, and labeling.  Design Requirements Masks must cover the nose and mouth.  They can't have valves or other things that allow unfiltered breath to escape. They have to say if they're one-size-fits-all or sized for d...

  Boy, wouldn't it be great if we had some sort of device we could point at people and have it tell us whether they're infected with SARS-CoV-2?  With the current gold-standard PCR test requiring big labs and hours to complete, fast, reliable virus detection has become a hot topic. Both Stanford and University of Minnesota have been working on portable devices to analyze samples faster.  DARPA wants gadgets that will detect the virus in the air. But all those require analysis of physical samples. That's so last century. Let's have something futuristic! Introducing   Covid Hunter , the "world's first non-contact viral detector." Supposedly, you point this thing at a person (or any sample from a person) and with "99% specificity and accuracy" it detects whether the virus is present. It works from up to six feet away, even through glass or another transparent material. Other claims and specs are here . This all sounds a little too good to be true...

This week the big trend in pandemic talk is "double masking." This is the practice of putting one mask on top of another to do a better job of filtering out virus aerosols.  Amanda Gorman did it at the inauguration , and we shouldn't underestimate the role of fashion here. Here is a chart based on Google Trends over the past 20 days, showing how the phrase has been picking up: The line really began to tick-up on the 25th, when Dr. Anthony Fauci endorsed the idea of double-masking by  saying   If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective, and that's the reason why you see people either double masking or doing a version of an N95 . Experts agree that a very important aspect of mask effectiveness is how well it fits. Masks that don't fit properly allow leakage of unfiltered air when inhaling and exhaling.  A leaky mask won't work well regardless of what material it...