Tag Archives: sterilizing immunity

Shreds of hope in the pandemic

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A Covid vaccine that’s in development could, potentially, create sterilizing immunity.

Sterilizing immunity? That’s the kind that prevents infection, which means a disease not only can’t get you sick, it also can’t use you to pass itself along to anyone else. If we could get enough people vaccinated with a sterilizing vaccine, we could stop this sumbitch in its tracks.

The snag, of course, is hidden in that word potentially. The thing’s still in development. But if all goes well, it could work on both the existing variants and any new ones and could create immunity even in people whose immune systems sleep through the current vaccines, through bouts of Covid itself, and through math class.

How does it work? 

“The SARS-CoV-2 subunit vaccine (PreS-RBD) developed at MedUni Vienna is based on a structurally folded fusion protein consisting of two receptor binding domains (RBD) of the SARS-CoV-2 virus and the PreS antigen from hepatitis B, which serve as immunological carriers for each other, thereby strengthening the immune response.”

Allow me to translate that for you: It’s magic. Don’t worry about it. Although you might want to know that it involves a series of shots to build up to full immunity, and the first trials could start this year. But that depends on funding. 

Irrelevant photo: an ornamental cherry tree. Or I think it’s a cherry.

What doesn’t depend on funding?

Hmm. Dunno. As society’s organized, not much.

Why do I ask so many questions? They’re a cheap and easy way to organize a piece of writing. 

See? Even that depends on funding.

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A second shred of hope is that researchers have found a monoclonal antibody that could potentially be a treatment for all Covid variants as well as for SARS and MERS (if they reappear), and for some versions of the common cold. But there’s that word potentially again. So far, it’s gone through animal studies. Next they have to capture some humans and test it on them.

It’s being combined with another monoclonal antibody, and the two together are going by the name AR-701 cocktail right now, but before they’re released into the wild someone will have to give them a less pronounceable name to make them sound more scientific. 

The plan is for people to inhale it, and it could–again, that word–potentially last for a year. 

Covid and male fertility

A very (very) small study raises the possibility that catching Covid could have long-term effects on male fertility. 

Long-term effects? When someone says that,they’re never talking about  good long-term effects. In this case, it means that men who had recovered from Covid had lower sperm counts, more misshapen sperm, and sperm with lower motility than the comparison group. 

Again, it was a small study, so don’t go off the deep end with it. But I can’t help thinking that if you want to discombobulate someone who’s pounding the table about vaccines messing with women’s fertility–

Nah. I’m not going to suggest that. I’ll leave it to you to sink that low.  

News about Covid tests

Two rapid, accurate Covid tests are in development. I’ve written that sentence so many times before, changing only the number at the beginning, that I’m not even going to give you the details. But testing’s another area where–out of sight of the general public–work’s going on that could have an impact on the way this mess plays out.

 

Covid and the sense of smell 

Omicron’s less likely than the Delta variant to mess up the senses of smell and taste, but a failed attempt to lower people’s viral load–that’s how much Covid they carry around–turned out to protect patients’ sense of smell and taste. It also left them less tired than the patients who got a placebo.

They were using a drug called camostat mesylate, and it’s not clear yet whether it would help restore smell and taste to people who’ve lost them. You can live without both of them, but taste and smell are not minor losses.

The drug will need more testing–which in turn means more time, not to mention more money–before it can be used this way. 

An update on Covid in Africa

One of the mysteries of an already pretty weird disease has been its impact on Africa. According to a World Health Organization’s estimate, 65% of people in Africa have been infected by Covid. That’s something like 100 times more cases than have been reported. Covid cases are undercounted everywhere, and more so in Africa, because so many people have no symptoms. 

When they say “estimated,” they’re not talking about an educated hunch. They’re basing it on blood samples from around the continent. It’s not as accurate as counting every head, but it’s not pulling numbers out of thin air either. 

Earlier in the pandemic, the fear was that Covid would devastate Africa, but it’s turned out to be one of the least affected parts of the world. Multiple explanations are on offer. It has a low percentage of people with risk factors like diabetes, high blood pressure, and heart disease. It has a relatively young population. And some studies suggest that having been infected with other diseases, including malaria, may be protective, but that hasn’t been confirmed and rushing out to buy yourself a case of malaria is not recommended.

But being one of the least affected parts of the world doesn’t mean Africa’s unaffected. It’s had 250,000 Covid deaths. Or known Covid deaths–they also tend to be underreported worldwide. Only 15% of Africa’s population has been vaccinated, and that may mean only one vaccination, since the article doesn’t say “fully vaccinated,” which is the phrase that usually pops up.

Is it safe to lift Covid restrictions?

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The latest Covid statistics from Britain are both cheering and worrying, although they’re starting to tip toward worrying. 

Nothing’s ever simple, is it?

On May 12, the country had only 11 Covid deaths and 2,284 cases. Compare that to January 22, when 1,401 people died of Covid and January 8, when the country had 68,053 cases. (Deaths peak a bit later than cases, which is why I seem to be cheating here.)

Some 67% of the British population is at least partially vaccinated. 

That’s the cheery part. So why don’t I just shut up and celebrate?

Blame those pesky experts. Also the pesky data they work with. And more to the point, blame the government–I’d think something was missing from my day if I didn’t–which dithered about whether to quarantine travelers coming in from India and about changing its let’s-all-proclaim-lockdown-over-and-be-happy plans.

 

Irrelevant photo: Ornamental cherry blossoms. We tried growing non-ornamental cherries. The birds didn’t even bother to say thanks.

Stephen Reicher, from Sage, the government’s science advisory group, is warning that the government has to be prepared to not to “dither and delay as in the past” if it turns out that one of the Indian variants has figured out how to sidestep the vaccines. He talks about acting hard and fast, which–well, unless the government gets a politico-personality transplant, isn’t in the cards.

Three of the Indian variants are known to be in the U.K., and one of them in particular is keeping the scientists up at night. It’s called B.1.617.2 by people who can remember that it’s called that, and in a week the number of cases showing its profile doubled in Britain. 

Sorry, It didn’t double, it more than doubled, although we’re not talking about a big block of people yet. A few days back, it was 520. What’s worrying is that it could be more transmissible than the Kent strain of the virus, which is the one that used to keep scientists up at night. Possibly as much as 50% more transmissible.

To some scientists, the tea leaves are looking frighteningly similar to the ones they saw before the Kent variant caused a surge in December of last year.

Come Monday, pubs and restaurants will get the okay to serve people indoors, and indoors among maskless people is exactly where the Covid virus likes to come out and play. So that adds to the worry.

Other restrictions are on a let’s-get-rid-of-these-soon list, including working from home if at all possible. And the travel industry’s been pushing hard to get people going on vacations again. Or on holiday if you speak British.

The new system to allow overseas travel involves traffic lights. Red, yellow, green–all those soothingly familiar colors. Arrive from a red-light country and you go into the kind of hotel quarantine that signals We’re Serious about This. Right after you mixed in the airport with people coming from green-light countries, who get to take a test and go home. 

What’s on the test? Three math questions, one logic question that the government will get wrong, and the old standby, Who was buried in Grant’s tomb? (The answer’s below.)

Any virus that violates the rules will pay a fine. 

Assorted scientists are warning that viruses don’t play by the rules and that it’s very hard to collect fines from them. 

Will the government back away from the planned reopenings? It’s dithering. 

The assumptions behind this are: 1. that 72% of the population will be vaccinated by August or will be protected by having recovered from Covid. 2. that most of the deaths will occur in people who’ve been vaccinated, since although the vaccines are startlingly effective none of them gives 100% immunity–not even against hospitalizations and deaths, although early reports said they did. No one’s to blame there. We’re learning as we go, every last weary one of us.

 

Controlling the variant

One way that Britain’s hoping to keep control of the variant is by intensifying the vaccination programs in areas where clusters are found. I have no argument with vaccinating more people, but there’s a two-week delay between vaccination and a decent level of protection, this isn’t an immediate solution.

On top of that, although the vaccines provide a much greater level of protection than we had any right to expect, they’re not like having your big sister or brother ride the school bus with you. In other words, they don’t give you 100% protection against either bullies or Covid. And when we’re talking about numbers as large as, say, the population of a country, a 2% gap in the protection can end up affecting a lot of people. 

So even though we don’t have any indication yet that B.whatever-whatever can run faster than the vaccines, its transmissibility alone means it’s dangerous. 

Modelers are warning about the possibility of a third wave of infections that could be larger than last January’s. If, that is, the new variant’s as transmissible as they fear.

Am I worried? I’m not losing sleep, but I wouldn’t advise anyone I love to start a travel business right now. Or to eat indoors at a cafe or pub. Because there’s no way to eat or drink without taking that damn mask off, and busy as scientists have been since the pandemic hit, they haven’t sunk their teeth into a solution to that problem.

 

WHO weighs in on a related topic

The World Health Organization has warned that vaccinations are “life-saving, but on their own, they are not enough.” 

That’s in response to the US’s optimistic and (I think) mistaken decision that fully vaccinated people don’t have to wear masks in many indoor settings. 

According to WHO’s Mike Ryan, “Relaxing measures and taking away mask mandates should only be done in the context of considering both the intensity and transmission in your area, and the level of vaccination coverage.

“Even in situations where you have high vaccine coverage, if you’ve got a lot of transmission, then you wouldn’t take your mask off.”

 

Collapsing the curve or watching it skyrocket

Almost from the beginning of the pandemic we heard the phrase flattening the curve. It was one of those word clusters–a bit like herd immunity–that we came to think we understood because we’d heard so often. Or read it.

Well, a new approach to modeling the epidemic says that if you make enough changes at a crucial stage, the curve doesn’t flatten, it collapses. In other words, you get to lace on your big muddy boots and stomp the little bastard. 

And if you miss that crucial time? 

Um, yeah. You have a massive damn outbreak on your hands. Or feet, if we want to hang in there with the boots metaphor. 

The most interesting thing is that the modelers couldn’t come up with a scenario that put the results anywhere between those two extremes.

One of the most powerful ways to control an epidemic is to test known contacts of infected people (which of course means finding them first and quarantine them if they test positive). But there’s a limit to how many people you can trace and test every day. If the number of cases goes past that limit, the disease spreads and congratulations, you’ve just lost control of your epidemic.

The key is to act early and decisively. (See above, Mr. Johnson.)

“A policy that would have worked yesterday will not only take much longer to take effect, but it may fail entirely if it is implemented a single day too late.” Björn Hof, the central mind behind the modeling, said: “Most European countries only reacted when health capacity limits became threatened. Actually, policy makers should have paid attention to their contact tracing teams and locked down before this protective shield fell apart.”

What Hof didn’t say but what seems to be implied here is that Britain’s strategy of lifting restrictions anytime the virus settles down to a less threatening level is self-defeating and leads to another spike later on. 

 

 

All right, gloomy guts, how about some good news?

Okay. In animal trials, a nasal spray vaccine has created sterilizing immunity. That’s the kind of immunity that (in words of one syllable) could wipe this bug from the face of the earth–or at least from your lungs. It would stop you from getting Covid and it would stop you from giving it to someone else. 

The current vaccines can’t go that far. They minimize the risk, and with it they minimize transmission, but they don’t eliminate it.

The vaccine needs only one dose, you don’t have to look away while someone pokes a needle into your arm, and it doesn’t have to be transported at temperatures so cold that sound freezes from the air and thoughts shatter. You probably wouldn’t want to deep fry it, but you don’t need to refrigerate it either. 

But it’s still got a series of trials to go through before we can get our mitts on it. Keep your eye on this one, though. It sounds promising.

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A cheap Covid test is being developed that reports back in four minutes and is 90% accurate. 

This one can work with either a nasal swab or a saliva sample and it’s actually a bit more accurate with saliva samples, meaning people could stop sticking thin objects up their noses. 

Didn’t our mothers all warn us not to stick things up our noses? Do you have any idea what we’re messing with, using swabs to test ourselves?

It can also spot infections in the early stages, which is important since that’s when they’re most contagious.

Have I written about this one before? I’ve lost track. It seems like some fast, accurate test is always in development. And then we hear nothing more about it. I’m hoping we’ll hear more about this one.

 

So who is buried in Grant’s tomb?

Grant is buried in Grant’s tomb. (That’s Ulysses S., Union general during the Civil War and later president.) 

When I was a kid, some hundred or so years ago, we used to ask each other this. Repeatedly. Maybe we thought the answer would’ve changed. I don’t know if kids in New York still do it. Grant’s tomb is along the Hudson River, begging for kids to use it as the base of stupid questions. 

I haven’t tried the question on anyone in a British airport. I probably should. 

The search for normalcy: can a vaccine block Covid transmission?

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With the number of vaccinated people in Britain growing, let’s talk about whether those of us who’ve had that magic needle stuck in our arms still need to be careful, and if so, who we’re being careful of. 

Answer number one is yes, damn it all, and answer number two is other people. Which you probably already know, so let’s take half a step to the side and talk about why.

The primary job of a vaccine is to keep people from getting sick, and the Covid vaccines do a better job than most. But very few vaccines get the infecting agent out of people’s systems completely. What they do is keep the infection at a level the body can deal with it. 

The rare vaccines that completely block an infection give us sterilizing immunity. The measles vaccine does that, and there may be others but I haven’t found a list and I’ve started to suspect that’s because the measles vaccine is the only one that would be on it. So no one–or no one who understood the situation–really expected sterilizing immunity from the Covid vaccines.

Irrelevant photo: hellebore.

What makes sterilizing immunity so hard to achieve? For Covid, the vaccine goes into the muscle but the virus goes into all those snotty places where our bodies create mucus. To expect sterilizing immunity from that combination is asking a lot. That’s not my interpretation. You don’t want my interpretation on this. I stole it from an article by someone who knew what they were talking about, but it does make an intuitive kind of sense. 

No, I don’t trust intuitive kind of sense any more than I trust my interpretation on this kind of thing. It can lead us so far into the dense fog.

An early trial involving rhesus macaques and the AstraZeneca vaccine suggested that sterilizing immunity was possible, but they were using a nasal spray. Why the nasal spray was abandoned I don’t know, but researchers are once again (or maybe that’s still) playing with the possibilities of nasal sprays. As usual, there’s no guarantee that they’ll work, but if they do they may prevent transmission. 

Or they may not. If you don’t hear about them again, they didn’t.

The current theory is that the vaccines we’re using can slow transmission but can’t stop it completely. They lower the amount of virus an infected person is carrying around, and that lowers the amount of virus the infected person spews out in the course of a day. 

But that’s a theory. Why don’t we know that for sure? 

Because the vaccine trials were set up to look for two things: bad reactions to the vaccine and symptomatic Covid cases. They didn’t look for asymptomatic infections. Finding asymptomatic infections would’ve meant testing tens of thousands of participants every time they walked through a doorway or found lint in their pockets. .

Some of the trials that are still running do test occasionally, and they’ll pick up some asymptomatic infections, and with them some useful information. The Johnson & Johnson trial suggests that the vaccine’s causing a significant drop in transmission. That’s still only a suggestion, though, not rock solid proof. It tells us whether the virus is present in people’s noses but not how infectious it is. For all we know, the virus could be sitting in there with its feet up, drinking tea, and having no plans at all for world conquest. 

The only way to be sure about transmissibility is through a challenge trial–one of those things where you deliberately infect people, or at least risk infecting them. With a disease that kills people and that we don’t have reliable treatments for, that’s hard to justify.

 

Challenge trials

Did I just make it sound like challenge trials have been ruled out? They haven’t been.

Challenge trials–and I’m quoting someone or other here, although I’ve lost track of who it is–are an ethical minefield and only justifiable if the benefits absolutely outweigh the risks. But Britain’s approved a Covid challenge trial involving 90 young, healthy volunteers.

The point of the trial is to figure out the smallest amount of virus needed to cause an infection. That–for reasons that haven’t filtered down to me (and yes, my feelings are hurt, but I’m sure I’ll get over it eventually)–will help doctors understand Covid better and also boost vaccine and treatment research. 

But again, with new variants imitating popcorn kernels in a hot kettle, any information we get from the trial is likely to be out of date by the time it’s published. Or even gathered. 

Add to that the knowledge that young, healthy people aren’t guaranteed to come through a bout of Covid untouched and you do have to wonder what the point here is. They can come away with long-term lung damage. They can be landed with lifelong problems that range from the annoying to the crippling. I won’t reprint the full menu of long Covid symptoms. Let’s just say that it’s one scary fucking menu, that not a lot is known about long Covid yet, and that you absolutely don’t want it. If people are going to roll those dice, it should be for something worthwhile.

 

Have I failed in my duty to complain about the government?

I get tired of complaining about Britain’s current government–its incompetence, its corruption, its sheer inexcusable existence, and I skip a lot of things that really are worth covering because I don’t want to do the blog equivalent of pounding a single note on the piano with a hammer. 

But with England’s schools set to reopen next week, it’s time to take a peek at the government’s plan to help kids catch up with lost schooling. The most disadvantaged kids, who’ve on average fallen behind more affluent kids during lockdown, will get tutored in small groups. 

Glorious. 

Only to get their hands on the funding, schools have to use an organization on the approved list of the “tuition partners.” 

Tuition partners? Yes, and someone got paid to come up with that phrase. It’s so bad that I went ahead and splurged on a set of quotation marks to keep it from leaking out into the rest of the post. 

Most of our friendly tuition partners are for-profit companies. One will charge £84 an hour to teach a group of three kids. And its pay for teachers–

Is it okay if we’ll call them teachers, not tuition partner self-employed contractors? 

Its pay scale starts at £15 an hour. I’m not sure what the top rate is, but you could take what the company collects for one hour’s tutoring and pay five starting-rate teachers (or tuition partner self-employed contractors if you insist) and still have enough left over for ice cream.

Another company is charging £72 an hour and paying a teacher with 16 years’ experience £31 an hour–43% of what the company’s getting paid. I don’t know what the starting rate is.

I seem to remember that the argument for privatizing absolutely everything was that private companies would be more efficient than government and save the taxpayer money. Tell me I’m not the only person who remembers that.

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As long as  I’m grousing about the general nastiness of the government we happen to have on hand, I just read that after announcing that it would extend the eviction ban–that thing that keeps tenants who’ve fallen behind on their rent because of the pandemic in their homes–they wrote in a big honkin’ loophole so that the ban doesn’t cover you if you’ve fallen more than six months behind.

Did they notice that there’s a difference between six months and a year-long pandemic? Probably. These are the numbers people.  

So, fanfare about no one getting evicted because of Covid, and people will get evicted because of Covid anyway.

In January, 750,000 families were behind on their housing payments (that category sounds like a combination of mortgage payments and rent), and pandemic rent debts added up £375 million. 

The National Residential Landlords Association wants the government to give tenants interest-free loans, which oddly enough will help the landlords but tenants who’ve been out of work for the past year to figure out how they’ll repay the loan.

Some sort of thought does need to be given to the debt that’s piling up on all sides. Maybe what we need is an approved list of companies that will help tenants file loan applications. The companies can take 57% of the money in payment for their services and the tenants can pay back 100%. 

We can call them loan application partners. And everyone will be happy.

Herd immunity, sterilizing immunity, and the current best guesses

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Britain is now the proud operator of several mass vaccination centers, with more promised shortly, and general practitioners are scheduling their oldest patients for vaccination. But that doesn’t mean we’re out of trouble. The number of hospital cases is still rising and there’s talk of the current lockdown not being tight enough.

And we just approved a third vaccine, Moderna’s. Not long ago, Boris Johnson was crowing at Scotland (which on average isn’t happy about having left the European Union) that if they’d stayed in the EU they wouldn’t have gotten vaccines so quickly. So it’s a nice little piece of irony to read that, approved or not, we won’t get or hands on this third vaccine until April because we’ve left the European Union.

I know I shouldn’t think that’s funny, but I can’t help myself.

 

Irrelevant photo: heather

Are we close to herd immunity?

The latest statistical modeling says one in five people in England may have already had Covid. How did they come up with that number? Since the official statistics inevitably underestimate the number of infections (a big chunk of people don’t get sick but carry the disease without knowing it or showing up in the statistics) and since the track and trace system is widely recognized as being roughly as useless as it is expensive, they get their statistics by comparing the number of deaths in an area to the estimated infection rate, putting them in a blender with a few other number and a dash of cinnamon, then baking at 160 C. for fifty minutes. 

In some areas, they estimate that one person in two has had the disease. The number of infected people may be up to five times higher than the number on the test and trace books.

Is that herd immunity? 

Nope. Exactly how many people would have to have had the bug to create herd immunity is still unknown, but a computational biologist estimates that 70% of the population will need to be vaccinated to stop the pandemic in the US. But that only applies to the US; it’s not a fixed number. People behave differently in different places, which upsets the numbers–they’re touchy little beasts–so they arrange themselves into different patterns. 

The number also depends on how long immunity lasts–no one knows yet–and on whether the vaccine turns out to keep people from passing on the infection. 

Most of our commonly used vaccines prevent severe illness but don’t give us what’s called sterilizing immunity. In other words, they keep us from getting sick–or at least from getting very sick–but they don’t kill off every bit of the disease that’s running around inside us. 

On the positive side, having less of the disease circulating inside our complicated little innards may (notice how much wiggle room I’ve left myself there) mean we pass on a milder form of the disease if we do give it to someone else.

An experiment with a chicken virus and a flock that was half vaccinated found that the unvaccinated birds came down with a milder disease than if the whole flock had been left unvaccinated. So even if the current vaccines don’t give us sterilizing immunity, Covid may yet follow that pattern and become milder once a significant portion of our flock has been vaccinated.

May. No one’s offering us a guarantee.

And no, none of the vaccines currently in use will cause us to grow feathers.

 

Transmission and hospitalization

In Britain, the current crop of hospitalized Covid patients are younger than they were during the first peak of the virus. People under 65 now make up 39% of hospital admissions. In March that was 36%. It’s not a huge change, but it is a change, and it’s worth noticing. 

The best guess is that the over 65s are more likely to be out of circulation. We left the party early and are tucked up in our little beds just now. That makes us less likely to become infected and less likely to show up in either the hospital or the statistics. But so much emphasis has been put on the elderly being vulnerable that we tend to think the non-elderly are made of steel.

They’re not. They can get very sick from this thing. In particular, pregnant women seem to be more vulnerable than non-pregnant women (or non-pregnant men, for that matter) in their age groups. 

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Half of all Covid transmissions come from people with no symptoms, including from people who never do develop symptoms. 

What does that mean in practice? That every one of us needs to act as if we could be carrying it. And that we need to look at our friends and family and neighbors as if they could be carrying it. That we need to look at other human beings and think, Oooh, yuck, germs! 

That’s not, I admit, a policy recommendation. It’s not even a real recommendation. It’s just an observation on how much it goes against the grain to live this way.

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A study reports that Covid can still be transmitted after seven days. Or after ten days. After ten days, 76% of the people tested still had detectable levels and 86% did after seven. 

So recommending a shorter period of isolation is a gamble. On the one hand, the theory goes that people are more likely to actually isolate themselves if you demand a shorter time. On the other hand, they can still be shedding the virus at the end of it.

The problem is not only that some people are jerks and don’t put the safety of others first. The larger problem is that a lot of people can’t afford to miss a day’s work–they’re living on the edge as it is. So when mass testing’s offered, they don’t show up because they can’t afford to be told to stay home. If they do end up getting tested and are positive, they stagger to work for as long as they can anyway. Because the hounds of hell are nipping at their heels. 

Already 70,000 households have become homeless during the pandemic and some 200,000 are teetering on the edge. There’s money available to people who have to self-isolate, but not to everyone and it’s not enough to cover the bills anyway. 

And if that doesn’t hold your attention, some people are still being told they’ll be fired if they don’t come to work.

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On a happier note, my partner’s been scheduled for her first vaccination. If all goes well (stop laughing–it could) I should be in line in mid-February.