Thread by @drdagly

This, among several evolutionary achievements has not only made #SARSCoV2 Delta a remarkable viral predator, but has also shaken our resolve about vaccination.

What you are looking at is a molecular catapult that smashes this virus into your cells. It’s the equivalent of a cellular trebuchet and it accelerates the rate of infection significantly. It’s this virological blitzkrieg that is the heart of our concern about vaccination.

There has been a lot of discussion about the utility of vaccination if people can still get infected and spread the virus. I think people have heard this enough to now doubt the effectiveness of these vaccines. Let me reassure you. They work.

All infections are a race against immunity. Just like a fire, it’s best you put it out when it’s small, because once it gets too big you lose control. Most infections follow exponential growth curves. Their goal is to out pace the limited resources of our immune system.

Wild type #SARSCoV2 was slow. With a primed immune system we could extinguish it before it reproduced to shed enough virus to infect others. Infact, in most cases we could nuke the virus before it reached a threshold of detection. This is the concept of prevention.

Really there’s a spectrum when talking about disease and viral load often correlates with it. By definition low grade infection must occur for immune reactions to be initiated. That’s when the race starts.

If our immune system wins before the viral load is detected then that’s not considered an infection. If the load is detectable but not enough to cause symptoms then that’s considered , you guessed it, an asymptomatic infection.

Unchecked proliferation leads to enough virus numbers that a person becomes infectious. This can be with or without symptoms depending both on the person and the rapidity of the disease. Many of the symptoms we experience are the direct effects of the immune response.

Therefore if infection rates outpace immune response the is a greater likelihood of asymptotic spread, until the immune system catches up.

Now if our immune system catches up before #SARSCoV2 gets too far ahead, we get mild disease, however if there is too much of a gap to overcome, or we catch up too late, we can see pretty horrible outcomes both from viral induced necrosis and secondary immune mediated injury.

This is why you want a fast immune system rather than a really strong one. hHow to you speed up you immune system? Training. With natural immunity you would rely on your innate immune system to defend the walls until your humoral immune system could place their antibody archers.

That usually takes a couple of weeks. That time is saved by vaccination and preformed antibodies. The more antibodies present the earlier the disease is snuffed out.

Antibody numbers taper down over time. They have too. You’re exposed to a lot of infections agents out there and if you didn’t focus your immune response your blood would turn into glue. The clinical term for this is hyper-viscosity syndrome.

T cells have the blueprints to rapidly produce new antibodies upon reinfection but it’s not as easy to quantify the cellular immune response hence the controversy about booster shots. It makes sense that it’s better to have antibodies at the go but we need real world data on that

In the end, we are probably better protected than antibody titres suggest.

So back to the vaccine. Initially it showed promise in preventing infection, the old virus was slow and inefficient. The vaccine made well functioning antibodies that in most cases stopped replication before viral titers reached detection.

This mechanism still works with delta. You are six times less likely to be infected when vaccinated. This is huge in preventing viral spread, propagation and new variants. However delta is fast. It gets off the line quicker and reproduces much faster hence higher viral loads.

There are preliminary studies that suggest that viral loads aren’t the whole story and though some spread happens in vaccinated individuals, it is significantly less. It would appear that many of these virons are coated with antibodies and hence unable to infect hosts.

Let’s not discount the reduction in severe disease outcomes, which are very relevant to keeping the healthcare system afloat and reducing long term disability.

So why did we go from a cure to a harm reduction strategy. Well, in short, we kinda blew it. As my ID colleagues can tell you, when you go for the king you dare not miss, and there’s a reason corona has a crown.

The reason we treat bacterial infections with a course of antibiotics is that you want to ensure you’ve killed every bacteria. If you don’t the ones that survive can pass on the traits that make them the strong ones. Spotty vaccination has allowed variants to evolve similarly.

And let me be clear. This is an arms race. Delta is the top dog for a reason. In addition to its ability to breach cells at frightening speeds, it shuts the cell down instantly, cutting the cellular phone lines and it’s silencing the cell’s abolishing to signal for help.

It redirects every single cellular resource into replicating virus, and it launches 10x the amount of mRNA into cells to amplify the process. This thing breaks in, hijacks the works and explodes out before our immunity knows what’s going on. So how do we beat it?

It’s going to take a multi pronged approach. High percentage homogeneous global vaccination rates. Like we did with small pox and polio. Yes, with annual boosters. This will take a protracted course of viral suppression.

We’ve got some promising protease inhibitors that have shown promise in reduction of disease severity and mortality.

forbes.com/sites/alexknap…

And public masking and federally mandated ventilation guidelines will become a way of life until this is beat down. I know some of you will grown at this, but the truth is the complex problems rarely have simple solutions. Policy, and politics will need to bend to nature on this.

In the end, this is completely manageable. The science is brilliant, and despite the dull roar of skepticism, completely valid. In the world of Covid, individual freedom will need to take a back seat to public health. Global cooperation will be essential.

Sorry, this was a long thread. I have spent a lot of time thinking about it. It evolved because I’ve been hearing a-lot of provocative questions out there. You all keep me on my toes. Now if you’ll excuse me I’m going to get some sleep. Be well. 🙂