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

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

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.