Tag Archives: new Covid treatments

The Covid testing dilemma

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England’s pushing mass testing as a way to contain Covid. It’s free, it’s government approved, it’s somewhere between uncomfortable and painful, and it may or may not be a good idea. Let’s tear the numbers apart and see what we can figure out.

Since the schools reopened, secondary students–those are the older kids–have had to do quick Covid tests twice a week, and that’s been a bulwark of the program to keep the schools open while not letting the virus get out of control. 

The tests, unfortunately, have a reputation for being unreliable, especially when done by non-experts. Since the kids are doing their own tests, or asking their parents or three-year-old sisters to stick the swabs up their noses and down their throats, these are in the hands of the distilled essence of non-expert. One fear about relying on the quick tests has been that false positives will send a lot of people into isolation unnecessarily. So half of the positive tests were sent to a lab to be confirmed by the slower, more reliable tests, and only 18% of them were false positives. 

Irrelevant photo: Rhododendrons. Photo by Ida Swearingen

But wait, because we’re not done yet. Those numbers are from March, and Covid rates have fallen, at least in parts of the country. (Some hot spots remain, and I don’t know if numbers are falling there as well. Just put that possibility off to one side. The recipe may call for it later. If it doesn’t, we’ll stick it in the freezer.) The point is that where the number of cases is lower, everything changes. 

Why? Because the tests will crank out the same number of false positives, no matter how many people are infected. Find yourself a population of people who’ve never been exposed to Covid and the test will swear on any religious book you like that some of them are infected. 

I’m about to throw some numbers at you, so if your allergies are bad today just skip a few paragraphs.

Ready? In London, the southwest, the northeast, and the southeast of England, the prevalence of Covid ranged from 0. 08 to 0.02. In England as a whole, it was 0.12%. Using those figures (I’d assume that means the England-wide ones), it would take 16,000 tests to find one infected person. If the tests cost £10 each, that means spending £160,000 to find that one person.

Is that worth it? If we were trying to stamp the disease out and keep it stamped, as New Zealand is, it would be. Given that we treat stamping it out as the silly thought of irresponsible day dreamers, probably not. 

Meanwhile, in leaked emails (I do l love a good leak) “senior government officials” are talking about scaling back mass testing, although the Department of Health and Social Care says it has no plans to end the program. One in three infected people, they remind us, show no symptoms but is still contagious. 

That brings us neatly to the question of whether the rapid tests will spot that one person. In other words, it’s time to talk about false negatives. Administered by an expert, the tests pick up 79% of infections. Or to put that the other way around, they miss 21%, and those are mostly people with a low viral load. Or to put that another way, they’re most likely to miss people who don’t have symptoms, who are just the people the testing program is looking for.

Administered by secondary school students or their three-year-old sisters, they’re more likely to pick up 58% of infections, or to miss–umm– I think that’s 42%. Although estimates of the number of cases the test misses vary. It might be as high as 50%. 

The government denies that it has any plans to scale back anything ever and Boris Johnson is urging everyone to get tested twice a week. Even though his advisors say that in areas with low infection rates, only 2% to 10% of the positive results may be accurate. 

But what the hell, guys, we’ve got these tests. Someone’s cousin has the contract for them. Use them, will you, please? For the good of the nation.

 

News of an accurate rapid test that’s in development

A new test is being developed that’s both fast and accurate. It also tracks variants and tests for other viruses that might be mistaken for Covid. It can screen 96 samples at a time and within 15 minutes it starts to report the samples as negative or positive. In 3 hours, it will have sequenced all its samples. 

It’s also small and portable. It doesn’t make coffee, but it just might be able to make you a cup of tea.

Juan Carlos Izpisua Belmonte, a professor in Salk’s Gene Expression Laboratory where it’s being developed, said, “We can accomplish with one portable test the same thing that others are using two or three different tests, with different machines, to do.”

That’s the good news. But will it go from development to being manufactured and used?

“Market analysis would be required to determine whether the initial cost of commercialization—and the constant tweaks to the test needed to make sure it detected new variants or new viruses of interest—are worth it.”

I believe that translates to “maybe.”

It’s called NIRVANA, which doesn’t seem to stand for anything, so I don’t know why it’s in all caps. 

 

High- and low-tech approaches to Covid

In New Zealand, they’re trying out an app that connects to smart watches and fitness trackers, monitoring people’s heart rate and temperature. It’s called an Elarm and the developer claims it can spot 90% of Covid cases up to three days before symptoms appear.

Does that include people who don’t go on to develop symptoms? I’m have to give you a definite maybe on that, because the article I found doesn’t address it. The company’s own website doesn’t answer the question either but says it will also let you know about stress and anxiety, although you might notice those without needing an app. Basically, it figures out your normal levels and lets you know when you’ve wandered off them, so you could end up going into isolation over the flu as easily as over Covid. That would scare the pants off you but would, at least, take a lot of the punch out of flu season.

So how do you use this? New Zealand wants its border force to try it out, since almost the only cases of Covid there are in incoming travelers, who have to go into quarantine, meaning the people who work for the border force are in the front lines.

When New Zealand says quarantine, by the way, they actually mean quarantine. It’s one reason they’ve been able to contain the virus.

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On the other end of the scale comes the recommendation that we open windows in public places to minimize Covid transmission. It’s cheap, it’s simple, and–

Oh, hell, how many public places these days have windows that open? Okay, ventilation. The air in public indoor spaces needs to be replaced or cleaned. 

We’ve heard a lot about keeping two meters (or yards) away from people to avoid contagion, but in addition to the heavier droplets people breathe out, which can carry Covid, the tiniest particles that we breathe out can also carry it, and they can stay suspended in the air for hours. The goal is to run them outside and get some fresh air in. 

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If you’re looking for a low-tech way to decide how far from people you should be standing, you can think of it this way: If you can smell that they’ve had garlic or peanut butter for lunch, you’re too close. 

 

Drug news

An asthma drug, budesonide, has been shown to shorten people’s Covid recovery time –and it can be used at home without anyone involved needing welding gloves, a deep-sea diver’s helmet, or a set of allen wrenches. It’s relatively inexpensive and comes in an inhaler. It shortened people’s recovery time by three days and at the end of two weeks the people who used it were in better shape than the control group.

It’s not clear yet whether it made hospitalization less likely. In the budesonide group, 8.5% were hospitalized. In the control group, that was 10.3%. That sounds like a result, but the problem with interpreting the numbers is that hospitalization rates are dropping in Britain. If you want to understand why that makes the numbers hard to interpret, you need to talk to someone who actually knows something.

Everyone in the test was over 50 and had underlying health problems. The drug can be used in the early stages of infection. 

The AstraZeneca vaccine update

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AstraZeneca’s vaccine is back in the news, and not happily. The company handed a group of US medical experts data on its effectiveness, but when the experts looked at it, they said, “Guys, this isn’t new data. This is the old stuff.”

Except that if they’d really used those words, they’d have said “aren’t new data,” because experts use the word enough to remember that data are plural. All experts. Even experts in knitting and basketball manufacturing. The word data is in a category that includes nonbinary people who prefer to be called they instead of he or she. Those of us who are over the age of a thousand struggle to get the pronouns and the verbs right. 

In case you’re interested, data is made up of lots of itty-bitty little datums.

No, sorry, that’s wrong too. A single datum has to have at least one friend before it become data.

Where were we?

Irrelevant photo: Blackthorn.

Basically, the experts were saying that AZ had cherry-picked its data to make the vaccine look like it was 79% effective. What the experts saw was between 69% and 74% effectiveness.

The craziness of all this is that a vaccine with 69% effectiveness is still damn good, and the advantage of AZ’s vaccine is that it’s easy to transport and store, so it doesn’t have to match the effectiveness of the fussier ones to be useful.

AZ said it had released interim data and that its later data (which rhymes if you pronounce your Rs the English-English way, like silent Hs) was consistent with it. Sorry: with them. It then released the lata data to the experts.

None of this is about the vaccine’s safety, but Dr. H. Cody Meissner, an infectious-disease expert at Tufts University School of Medicine who serves on a board that advises the US Food and Drug Administration on vaccine approvals, said, “You know the anti-vaccine community is going to use this as fodder to argue that pharmaceutical companies are always deceptive.” 

He said board members would be even more careful than usual to scrutinize AZ’s  data from here on, and “I will make sure I don’t skip a word.”

Which is probably not the response AZ was hoping for.

 

Yeah, but what about the AZ vaccine’s safety? 

A number of countries put the AstraZeneca vaccine on hold for fear that it was linked to a very rare blood clotting problem, cerebral venous sinus thrombosis. AZ’s recent US trial involved 21,000 people and turned up no safety concerns, although when a problem’s extremely rare it could easily not show up in a sample of that size. Or of ten times that size.

But even if the vaccine does, very rarely, cause cerebral venous sinus thrombosis, the risk of not using the vaccine is much greater than the risk of using it. Either all or most (or, hell, I’ve lost count; let’s just say many) countries that put it on hold have by now started to use it again. 

 

Magical Covid solutions that may turn out to be real

I try not to write about Covid solutions that are still in the trial stage, because we may never hear of them again, but every so often I can’t stop myself, so let’s talk about protease inhibitors. They’re antiviral treatments in pill form that can be used in the early stages of an infection to keep the virus from multiplying.

What’s a protease inhibitor? It’s a–

Would you mind if I duck that question? We can all live perfectly full lives (and pretend we understand this) without understanding this fully. So a protease inhibitor is a thing–probably one that inhibits proteases–and it’s already been used to treat other viruses, including HIV and hepatitis C. It’s also been used to treat Covid, but up to now it has to be delivered into the blood stream slowly, so its use has been fairly limited.

As someone or other said, “This is really a potential game changer.”

One of the unexpected side effects of the pandemic has been that experts and politicians are required to use the phrase game changer at least once a week. By now, we’ve changed games so often that we don’t know if we’re playing cards or jump rope, or possibly that game involving horses, mallets, and a the head of a dead goat. But as long as we’re changing games, I should mention that they’re exploring the possibility that the treatment could also be used in people who’ve been exposed to Covid but who haven’t yet developed it.

Folks, this really does sound–ack–game changing. Have you got your goat’s head? The price is only going to go up, so if there’s room in your freezer you might want to buy now.

Because Covid’s protease doesn’t mutate much (at the moment, anyway), this would work against all the current variants.

All this made me so happy that I made myself an extra cup of tea this morning. 

Yes, I live close to the edge.

 

The lockdown report

England’s current lockdown rules are scheduled to ease up on March 29. People will be able to get together outdoors in limited but larger groups. People will be allowed to leave home for non-essential reasons. (Hands up: How many of you remembered that we haven’t been allowed to do that? I just thought there wasn’t much non-essential to do.) 

But non-essential shops and services (barbers, hairdressers, that kind of thing) won’t reopen until April 12, along with bars and cafes that have outdoor seating. (No eating or drinking indoors yet.)

Why is April 12 safer than March 29? The virus is afraid of even numbers. It’s all been worked out by people who know what they’re doing. Unfortunately, they had to run their recommendations past Boris Johnson’s government, which threw all the cards in the air and picked them up in random order. Still, some semblance of sanity may still be in there.

Okay, I’ll admit: That was unfair. The idea is to take this thing in stages and only go to the next, more open, stage if Covid stays below some unspecified level. 

The travel industry had been hoping that foreign travel would get the green light, but it hasn’t–or at least overseas vacations haven’t. Or holidays, as you’d say if you’re British. You can’t “leave England to travel to a destination outside the United Kingdom, or travel to, or be present at, an embarkation point for the purpose of travelling from there to a destination outside the United Kingdom” without a reasonable excuse.

Is that clear enough? It means you can’t leave, travel to, be present at, or consider the possibility of thinking about getting ready to go somewhere else. And if that didn’t cover all the possibilities, it’s because I nodded off after one of the ors.

But in spite of all the repetition, there are exceptions, and they’re hidden in that bit about reasonable excuses, which in spite of being outside the quotation marks is a quotation, but one that went wandering and doesn’t belong in that particular spot. 

If you need to travel for work or study, to vote, or for legal obligations, you’re okay. If you need to be present at a birth. If you’re visiting a dying relative or close friend. If you’re getting married. If you have a medical appointment. If you–well, a few other things. 

The reasonable excuse that’s raising eyebrows is that you can travel to get a second home ready to sell or rent. Or you can travel if you just have to buy or rent one. Or to do a few other things with one. Because if you have the money to buy, sell, rent, or hand Christmas lights on a second home, you’re more important than someone who’s hoping to stay in a youth hostel in Spain for a week or two. And if you’re more important, you’ll have the sense not to import some new Covid variant.

That’s being called the Stanley Johnson clause, after the prime minister’s father, who traveled to his villa in Greece to make it, he said, Covid proof. I don’t think he’s told the rest of us how that’s possible. But no, it wasn’t so he could sit in the sun and drink himself senseless. 

Sorry–I suckered myself into a stereotype there. I have no knowledge of what Johnson Sr’s drinking or sunbathing habits are. 

What’s a villa? “1. A country estate. 2. The rural or suburban residence of a wealthy person.” Or in British real estate-speak, “3. A detached or semidetached urban residence with yard and garden space.”

For Stanley Johnson, we can, I think, rule out the real estate-speak definition.

I’m happy to report that protests will be exempt from the rules banning large gatherings, but the organizers will have to work out (or encourage, or some other vaguely related verb) social distancing and mask wearing. That sounds surprisingly reasonable, although it leaves a worrying gap that allows for breaking up spontaneous demonstrations, even if people wear masks and keep their distance.